Fieldlines.com: The Otherpower discussion board
Homebrewed Electricity => Wind => Topic started by: topspeed on June 12, 2019, 01:13:25 AM
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If someone is interested of these let's discuss it ( H-Darreus ) here !
I have done 2 prototypes and yesterday in 10 m/s wind I was able to get 1900 rpm reading of the wing ( on the island of Hailuoto ).
With the given measures of my turbine ( roughly ) 1 x 1 meters..it dictates a speed of 101 m/s for the wing.
Thus it yields 10.1 for TSR. G-force in the wing was beyond 100.
Enclosed is the Marious Paraschivoiu tests results in Concordia Uiversity in Canada for a 7 KW system.
I had a very underrated generator on my device...that helps it reach a higher speed sor sure.
Marius Paraschivoiu is the son of Ion Paraschiuvoiu who is a master in H-Darreius research.
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1900 rpm ! :o
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I have done 2 prototypes and yesterday in 10 m/s wind I was able to get 1900 rpm reading of the wing ( on the island of Hailuoto ).
With the given measures of my turbine ( roughly ) 1 x 1 meters..it dictates a speed of 101 m/s for the wing.
1900 rpm at the wing? what part of the wing? This does matter.
Do you happen to have a picture of the measuring device showing these RPMs?
Also would like to know if this was loaded or unloaded.
IF loaded what type of load ? any measurements of watts produced?
Bruce S
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I have done 2 prototypes and yesterday in 10 m/s wind I was able to get 1900 rpm reading of the wing ( on the island of Hailuoto ).
With the given measures of my turbine ( roughly ) 1 x 1 meters..it dictates a speed of 101 m/s for the wing.
1900 rpm at the wing? what part of the wing? This does matter.
Do you happen to have a picture of the measuring device showing these RPMs?
Also would like to know if this was loaded or unloaded.
IF loaded what type of load ? any measurements of watts produced?
Bruce S
Hi Bruce,
No picture to show the reading...this is very unofficial. In fact it was very tricky ( and dangerous ) to take the speed measurement as it sometimes showed the double speed of 3600 rpm..as the device also measured the wing going behind ( if not pointed correctly ).
It only has a used bicycle hub generator with a light swiched on...so there was 30-50 watts at tops the resistance..as the wing sweeped at 365 km/h.
Good thing about my turbine is that I can always repeat the test and even enhance the machine. It has no marks of wearing down...yet.
I think it measures the wing upper side.
Juke
PS: The Kavan was on two props and showed 19 on it..once...18 more times.
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I hope you plan to install a much larger generator than 30 W. Your blades are overspeeding and despite your current success they will probably find a way to fly apart if they continue to run that fast. Your machine seems to have much more aerodynamic power available than you are taking out with the generator. In fact, you really should be looking for a ~200 Watt load or perhaps more.
There's some potential so I hope you get the chance to show it.
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I hope you plan to install a much larger generator than 30 W. Your blades are overspeeding and despite your current success they will probably find a way to fly apart if they continue to run that fast. Your machine seems to have much more aerodynamic power available than you are taking out with the generator. In fact, you really should be looking for a ~200 Watt load or perhaps more.
There's some potential so I hope you get the chance to show it.
Yes thanks SW,
We are on it..possibly a car part could do the trick ( 1 kw ).
Juke
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There is something very weird here now.
The G-force is 2000 when we recounted it.
I did think the pivoting system and actuator sorta divide the metric ton pulling force in to sturdy 3-point attachment points..but also the 1,5 mm thick plywood covering is to blame too. The weird foil is optimal for stressed skin..kinda like shell structure.
I am pretty sure it will brake at 15 m/s wind.
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Batteries must be dying..or some reflection makes a double signal...1900 / 4 would be 475 rpm.
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Here is vital info that possibly explains why the wing did not explode week ago...spanwise flow.
https://aviation.stackexchange.com/questions/38482/where-is-the-spanwise-flow-how-does-the-span-wise-flow-point-the-air-towards-th
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I have now tested two times with a new rpm meter.
More modest data available. ;)
Highest speed was 377 RPM...yielding around TSR of 3.
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8) cool
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I am working on a bigger generator to be able to measure the output.
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8) cool
New arrangement provided steady ground attachment. Old one failed.
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I am working on a bigger generator to be able to measure the output.
8Fun hub motor? Would be interested in knowing more about this.
Thanks,
CM
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I am working on a bigger generator to be able to measure the output.
8Fun hub motor? Would be interested in knowing more about this.
Thanks,
CM
I will inform as I progress on it. It is a 250 Watt system.
Problem with currect dynamo is that is has too little drag ( 5-14 watts )...for high winds.
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I always wondered about maybe small VAWT could use a rider mower electric PTO clutch (minus the brake) to engage when windspeeds get to RPMs that need more load. You only need 40W to engage most types good for up to 25hp. The PTO could engage a more robust resistance PMG to drive down RPMs. (It would probably burn out the clutch in no time.) Your experiment is quickly reaching enough power to maybe provide enough juice for a PTO clutch.
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Nice way to start the morning too, Cafe' Mocha, Beignet, and thoughts of electronics "stuff" . 8)
I too will be interested in seeing how well this goes. In our City, we cannot have HAWTs, way too many overhead wires.
However, up to 8 feet (2.3M) about ground level we can have "yard art" Which is what VAWTs have been labeled as.
I have a very nice ECM from GHURD that I've been grooming to put up.
I'll be watching to see how well this goes.
Cheers
Bruce S
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I always wondered about maybe small VAWT could use a rider mower electric PTO clutch (minus the brake) to engage when windspeeds get to RPMs that need more load. You only need 40W to engage most types good for up to 25hp. The PTO could engage a more robust resistance PMG to drive down RPMs. (It would probably burn out the clutch in no time.) Your experiment is quickly reaching enough power to maybe provide enough juice for a PTO clutch.
I discovered the gyroscopic force is strong on this...so possibly it could be run in a heavy storm....reaching KWs.
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I will make a set of bigger wings to get a better re-area...swept area stays the same.
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I discovered the gyroscopic force is strong on this...so possibly it could be run in a heavy storm....reaching KWs.
But the aerodynamic forces also ramp up dramatically in strong winds.
So do the forces imposed by mass imbalances.
Which means, "NO" these cannot possibly be run in heavy storms. It will reach Zero KWs.
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I discovered the gyroscopic force is strong on this...so possibly it could be run in a heavy storm....reaching KWs.
But the aerodynamic forces also ramp up dramatically in strong winds.
So do the forces imposed by mass imbalances.
Which means, "NO" these cannot possibly be run in heavy storms. It will reach Zero KWs.
You are right there is a strong MICROVIBRATION going on in a heavy wind...but no tendency to tumble it down.
I figure you just have to live with the vibrations and not let it escalate. It shall not sorta yield to the cyclical work phase that causes the vibrations.
My next model concentrates along with current measuring to these microvibration handling aspects.
Lumber is stronger than on the proto number 2....also the structure will be more steady.
My latest test day failed me as I only clocked TSR 3 figures as the soil was loose...I was on the low tide sea bed.
I will also double the re-number on the wings.
Some of this could be applied: https://www.youtube.com/watch?v=97t7Xj_iBv0
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The new bigger turbine is beyond half way ready. I have even painted a part of the middle piece ( connects the blades ) of the advanced pitch controlled H-Darreius.
I have attented few fluid dynamics classes at the university to obtain doctor degree to be able to present the system/innovation more precisely.
Wing will be roughly 1 kg a piece and middle part around 6 kg with generator..... legs/tower roughly 8 kg. Reynolds area increases about 100% from the previous..it is still smaller than the McDonnell Aircraft Giromill proto in 1975-1978.
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Upper part of the tower is taking shape..not rounded yet.
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Looking good topspeed, thank you for the progress report.
Ed
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Thanks MJ.
I do something everyday.
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Bigger tower is getting legs attached..for testing the fit.
I will do a major modification on the hub-motor next....after painting the tower.
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3 KW hubmotor tweaked to produce 12 KW ( not mine ).
https://www.youtube.com/watch?time_continue=15&v=KU1Axy4bVYE (https://www.youtube.com/watch?time_continue=15&v=KU1Axy4bVYE)
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This used hub started to rotate at 75% less friction than with the planet gear..which I deactivated and threw into trash.
At best of conditions they claim 78% efficiency with the planet gear....I figure I rised the efficiency to 96% by taking off the unnecassary gear.
I also had to wedge the rotator to the core ( using duct tape ).
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I have to do a fairing to the tower....just in case. :-\
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I erected the new turbine's tower...and tested the old one.
I was kinda sad that I forgot to bring all tools with me...as this new tower fits also to the older turbine's top part.
1-2 meters higher the wind was 10-12 m/s and a bit lower 7-10 m/s.
Highest 928 RPM was indicated...and 904.
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Great looking location overlooking what I presume is an ocean in the background. Do you experience corrosion problems with the salt air?
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Great looking location overlooking what I presume is an ocean in the background. Do you experience corrosion problems with the salt air?
My engineer deviced me to turn into steinless steel.
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Hackaday the other day about VAWT: https://hackaday.com/2019/10/05/building-a-wind-power-generator-in-your-backyard/#more-378893
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I have been able to test that the generator works without the reduction gear. I also started with the control panel.
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It will have rubber isolators like doubled..to be able to read the meters as the prototype is running...without concrete foundations.
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This should be easy enough to read.
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Very nice!
I like tidy work - especially when it's got some symmetry.
I'm a bit "OCD" that way.
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Very nice!
I like tidy work - especially when it's got some symmetry.
I'm a bit "OCD" that way.
Thank you...I am working on it.
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I got the rectifier sorta positioned now.
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I had to put the planet gear back.
I am getting 14 volts with hand cranking the shaft.
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I am at awe now....as I am not electrical engineer.
How much can be the efficiency of a generator in general ?
I think when I hand crank my wind mill arm....that it isn't converting the force into electricity no where near the percentage that would be worthwhile.
Let's assume that the wind generator turns 50% of the wind energy into mechanical motion...how much of that 50% can be harwested with an electrical generator in the best scenario ?
Any calculations available anywhere ?
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It can be calculated, but it takes a lot of measurements through the whole the system to compute an answer (atmospheric conditions, rotor blades, electric generator configuration, power conversion system).
It's often easier to just measure it.
Mechanical power = (Torque)X(RPM)/(conversion factor)
Electrical power = (Volts)X(Amps)
The aerodynamic conversion is 50% efficient at best, but often less. Mechanical conversion to electricity can vary between 70% and 20% depending on the generator. The one I'm using varies between about 50% at low speeds to 40% at higher speeds. I pay a price for robustness. I remember when Kitestrings published info about his alternator build (about 5 years ago) I was impressed by its efficiency. Though I don't remember the exact value it was quite high.
When converting mechanical to electrical energy, the majority of energy lost goes to resistance heat. If the windings have 10 ohms resistance, then passing 10 amps through them releases 1000 Watts as heat. If the same generator had reached 100 Volts as a result of that work, then it generates 1000W of useful electric energy. The sum of the two outputs (useful and non-useful energy) requires 2000 Watts of mechanical power at the driveshaft to make it. And my example generator would be 50% efficient.
I simplified my example so that I wouldn't have to consider 3-phases and rectifiers. They have a role to play in practical generators, but I hope the example is complete enough to get the idea across.
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Yes SW !
I appreciate this answer.
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Picture below..is now 100 watt H7 halogen in my system.
This is doing 12,5 volts and 5.2 amps by hand cranking it.
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Great looking location overlooking what I presume is an ocean in the background. Do you experience corrosion problems with the salt air?
Here are my locations....very secretive as I have not patented my innovations on it.
It is in the north part of the Baltic Sea.....50 KM from City of Oulu by car.
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Yes and the Island is west of it..south west slightly.
There is an old nazi build airfield on test site 3.
During WW II..nazi's occupied northern Finland.
In Oulu there was a big german garrison as well.
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My daughter brought me 2 small jam jars from Rome the other day. I recycled them.
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It's coming together all right.
Just for information (I can't be sure if you know about this already) lamps are variable loads in electric circuits. The resistance of the filament varies as it heats up. I'm not even sure if Halogen lights are as bad as the incandescent ones. But heat plays a role and it has interesting effects. It can make you stop believing in Ohm's law until you consider that effect.
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Are you going to use a little S glass cloth and epoxy to skin your blades?
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Are you going to use a little S glass cloth and epoxy to skin your blades?
I think I will.
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It's coming together all right.
Just for information (I can't be sure if you know about this already) lamps are variable loads in electric circuits. The resistance of the filament varies as it heats up. I'm not even sure if Halogen lights are as bad as the incandescent ones. But heat plays a role and it has interesting effects. It can make you stop believing in Ohm's law until you consider that effect.
I am able to hand crank 91 watts ( 11.25 Volts x 8.09 Amps )...with 2 x 100 watt H7 halogens.
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I added third lamp and cranked 128,3 watts. ::)
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I have been watching closely the developement of the Idaho based Tilt Rotor system.
https://pdfs.semanticscholar.org/b002/69b9676d4575e6dce217315eade9ef3a08f1.pdf
Does anyone see anything strange in the displayed values there ?
Are they any longer in business ?
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After attaching an image, please click on the actual (and rather big) "Insert image" button next to it, so the image itself will show up in recent posts as well and will also show in the middle of the post itself (making things easier too, since you can say I've done this - post image, then this - post another image and so on). Thanks!
Currently trying to find a way to see if I can remove the end of post attachments altogether, didn't think people could miss the button :( It's a pretty new system and we don't have an up-to-date how-to quite yet, but still :P
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After attaching an image, please click on the actual (and rather big) "Insert image" button next to it, so the image itself will show up in recent posts as well and will also show in the middle of the post itself (making things easier too, since you can say I've done this - post image, then this - post another image and so on). Thanks!
Currently trying to find a way to see if I can remove the end of post attachments altogether, didn't think people could miss the button :( It's a pretty new system and we don't have an up-to-date how-to quite yet, but still :P
Okay...greetings to Italy...my daughter brought these light cones from breakfast table in Rome recently.
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I will add this blue 55 watt H7 just about now into the rear jar.
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Thus I will have a circuit of 255 watts.
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Ciao Topspeed, and all lovers of Italian things.
Your equipment is coming together nicely. I can't see it so may I ask: have you a way to turn each of the lamps on or off? It will allow you to vary the electrical load on the turbine. That can have interesting effects.
As for the other documents and charts you are posting, I'm afraid they are just as bad as the junk you found last month.
The "Idaho tilt rotor" paper is actually a student's undergraduate thesis paper, where nothing was built. Nothing in that paper has been validated.
The chart you posted is worse because it plots impossible curves with no data to support the claims. You're not going to get me to click on the sale brochure link to find it.
You have also made your own edits to the image thereby declaring yourself as on the side of "inventing reality". I have warned you about this in the past. The words are acknowledged, but the meaning is not sinking in. Why are you not examining these things yourself critically?
When you build, I will encourage you. I will also offer suggestions that may improve your success or safety.
When you measure what you built, I will support you. I will also offer tips to improve the quality of your results.
When you post the imaginary results of others, I will remove them. In this case I will red-flag your graphic and allow a second moderator to decide.
When you make claims of your own that are obviously false, I will ban you.
DamonHD: previous topspeed post now removed by me.
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Ok notice received...let's keep the speculations out of this.
Yes..there will be switch to CUT-IN....and CUT-OUT via short circuit.
Also the connections to each lamp are very fast to operate for desired out put level.
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That's what I like to see. Thank you!
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I seem to be slower in the winter time. :'(
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I have assembled a lot of built-up wings for R/C aircraft and always felt this type of construction is a good choice for a constant chord VAWT blade. They can be built to be very strong and stiff. With a fiberglass cloth and resin skin the outside can withstand a lot of abuse as well.
You probably already know this but adding a vertical grain sparweb piece between the top and bottom spars will add a great deal of strength.
Great looking work!
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Ok...I will add a spar web. ;)
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Well...as this is not a wing but a tower cover...it needs no spar nor web..as the tower itself is one.
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I nearly blew this...as the tape did not attach when the epoxy made everything slippery. But the pop riveting saved the day.
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Ahh! Makes sense now, I can see the reason for the square cutout in the ribs. Was wondering why they were there.
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Ahh! Makes sense now, I can see the reason for the square cutout in the ribs. Was wondering why they were there.
Yes...this cuts down the tower drag about 95%.
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There are many VAWT companies in eastern Europe.
Maybe russians will have one soon ?
https://www.youtube.com/watch?v=3RuOOEULaeo
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very interesting
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very interesting
I wonder if this is the only available adjustable ( pitch controlled ) VAWT in the market ?
https://www.youtube.com/watch?time_continue=47&v=CNHUiJ6Voqk (https://www.youtube.com/watch?time_continue=47&v=CNHUiJ6Voqk)
TechAdmin - fixed weird link :P
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Tower fairing is wood ready.
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If the drill is 500 watts output....and I use my box to measure out put of the generator ...is this useless ?
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Ahh! Makes sense now, I can see the reason for the square cutout in the ribs. Was wondering why they were there.
Yes...this cuts down the tower drag about 95%.
(Attachment Link)
One has to be alert what area is used if drag coefficients are compared for different geometries. For a real drag body like a sphere, an angle iron or a car, one takes the area of the body perpendicular to the wind. For an airfoil, one takes the product of the airfoil chord times the airfoil width. This product is much larger than area of the airfoil perpendicular to the wind because the airfoil chord is much larger than the airfoil thickness. Airfoils therefore have very low drag coefficients if compared to drag coefficients of real drag bodies but this is partly because for an airfoil, a much larger area is used when the drag coefficient is calculated from the measured drag. The drag coefficient for an airfoil is defined in formula 3.2 of my public report KD 35.
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Ahh! Makes sense now, I can see the reason for the square cutout in the ribs. Was wondering why they were there.
Yes...this cuts down the tower drag about 95%.
(Attachment Link)
One has to be alert what area is used if drag coefficients are compared for different geometries. For a real drag body like a sphere, an angle iron or a car, one takes the area of the body perpendicular to the wind. For an airfoil, one takes the product of the airfoil chord times the airfoil width. This product is much larger than area of the airfoil perpendicular to the wind because the airfoil chord is much larger than the airfoil thickness. Airfoils therefore have very low drag coefficients if compared to drag coefficients of real drag bodies but this is partly because for an airfoil, a much larger area is used when the drag coefficient is calculated from the measured drag. The drag coefficient for an airfoil is defined in formula 3.2 of my public report KD 35.
I have perfect proportions on this according to Hoerner...1:3.7 ( 27% thick ).
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according to Hoerner...1:3.7 ( 27% thick ).
Now THAT'S an excellent reference for your work!
https://hoernerfluiddynamics.com/
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Ahh! Makes sense now, I can see the reason for the square cutout in the ribs. Was wondering why they were there.
Yes...this cuts down the tower drag about 95%.
(Attachment Link)
I have perfect proportions on this according to Hoerner...1:3.7 ( 27% thick ).
(Attachment Link)
A thickness of 27 % of the chord is very large. The drag coefficient of an airfoil normally increases with the airfoil thickness but it also depends very much on the Reynolds number. If you have used this airfoil to cover the tower pipe, the drag will certainly be lower than that of a pipe and there will be much less turbulence which destroys the flow around the blade when it is at the back side. But if you use such a thick airfoil for the rotor blades, you have to calculate the Reynolds number at moderate wind speeds and check the Cd/Cl curve of the airfoil for this Reynolds number to see if the Cd/Cl ratio is low enough.
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You mentioned a while that you are being secretive about location because you haven't patented it yet? What is there to patent? Doesn't really seem like anything that is that novel
I would definitely advise against patenting.. For private inventors it just doesn't seem worth it. And at the end of the day, if you get your patent, are you prepared to defend it? The money needed to make a patent is nothing compared to what you'll dish out trying to chase down anyone who infringes! (If it really is that amazing ;) )
Nice build though! I have always been so intrigued by VAWT's!!
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There are about 12 new innovations in this.
That tower fairing is one....here is another one.
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These wheels are for being able to mount the moment arm that connects the wings inside for testing...without damaging the links !
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Additional 3 lamp console for this H-Darrieus.
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Possible fire hazard has been avoided like this !
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Situation on the leg will provide light reflections from the rotating wings.
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I am using XFLR-5 CAD program to see some situations in my VAWT wing....are these generally trustworthy ?
http://www.xflr5.tech/xflr5.htm
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Meh:
http://www.xflr5.tech/docs/Part%20IV:%20Limitations.pdf
If you enjoy experimenting with it, and learning as you go, then great.
It's not a real answer for any calculation you give it, though.
It's most accurate if your wing is a perfectly flat plane. If you have an airfoil, it's only an approximation. The more thickness and camber, the poorer the approximation.
Yes, that "5.436" would give me pause, too.
The advantages to perfect airfoil selection will be very difficult to measure. Won't be obvious unless you build two complete sets of blades and measure performance from them both. With fluctuating wind, the difference will vanish in the scatter of the data you collect.
Just get the angle of attack right, and a smooth surface, a fair rounding to the leading edge, and a sharp trailing edge.
My HAWT blades are pulling in a CP of about 50% +/- 10% with an approximate NACA airfoil. I really don't care about the remaining 9% enough to make another set with another airfoil on the speculation that it will improve anything within my ability to measure.
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Meh:
http://www.xflr5.tech/docs/Part%20IV:%20Limitations.pdf
If you enjoy experimenting with it, and learning as you go, then great.
It's not a real answer for any calculation you give it, though.
It's most accurate if your wing is a perfectly flat plane. If you have an airfoil, it's only an approximation. The more thickness and camber, the poorer the approximation.
Yes, that "5.436" would give me pause, too.
The advantages to perfect airfoil selection will be very difficult to measure. Won't be obvious unless you build two complete sets of blades and measure performance from them both. With fluctuating wind, the difference will vanish in the scatter of the data you collect.
Just get the angle of attack right, and a smooth surface, a fair rounding to the leading edge, and a sharp trailing edge.
My HAWT blades are pulling in a CP of about 50% +/- 10% with an approximate NACA airfoil. I really don't care about the remaining 9% enough to make another set with another airfoil on the speculation that it will improve anything within my ability to measure.
Yes.....two sets of blades would do it.
Someone told me the number above counts only if the wing kept on going at M 0,2 at that high AOA. That never happens.
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Interesting small turbine electrical data: https://www.youtube.com/watch?v=r-cmCHEhN3k
Fuses are in the AC cables...neat !
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Wings are taking shape. :o
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Merry Christmas everyone !
I am slightly farther now...as for the first time I attacheded the wing on the lever arm yesterday with my daughter.
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New winglets took 4 days to make and finish. I had to invent a new tool for them.
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What do you think of these winglets/endplates ? ;)
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Everything you've done looks like high quality.
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Merci beaucoup Matt ! :)
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Here is a pitch control mechanism like Pinson and Roman Buhler had on theirs.
Vane based timing: https://iopscience.iop.org/article/10.1088/1742-6596/524/1/012055/pdf
How many have tried that ?
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The US DOE has: https://www.osti.gov/biblio/6046045
https://wind.nrel.gov/public/library/SERI_TP-35-263.pdf
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Loks like the McDonnell Aircraft Giromill fronm 1978.
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Are you an aircraft homebuilder by chance? All of your worksmanship looks very high quality and homebuilt aircraft influenced.
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Are you an aircraft homebuilder by chance? All of your worksmanship looks very high quality and homebuilt aircraft influenced.
I have decided to build a homebuilt after this. So that is what you might see here...a 20 years dedication to build an aeroplane.
My first prototype or proof of concept was made of the root wing panels of my intented homebuilt planes 1/3 scale model.
I have build many radio controlled models. Kent Walters, Chad Veich and those dudes are my friends...like Paulo Iscold.
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Here are the wings/blades....as wood ready state. :D
I am slightly worried as while Re-number is fine the AR (aspect ratio) is not that great...but I might make another set of wings.
Those both weigh 2118 gramms each...and 5 lbs when painted.
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What do you think of this VAWT ?
Looks very interesting in general.
https://www.youtube.com/watch?v=_hnrOn-pTHQ
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i like the squirrel cage type.
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I like the fact they show the gen part too.
I'd like to see the output numbers.
It was nice to watch :-)
Thanks for the post!
Bruce S
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What do you think of this VAWT ?
Looks very interesting in general.
https://www.youtube.com/watch?v=_hnrOn-pTHQ
How do you stop such a monster when one arm breaks??
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I like the fact they show the gen part too.
I'd like to see the output numbers.
It was nice to watch :-)
Thanks for the post!
Bruce S
Be my guest ! ;)
How about this Vertogen ?
https://www.youtube.com/watch?v=a-Kv5AB3RH0
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What do you think of this VAWT ?
Looks very interesting in general.
https://www.youtube.com/watch?v=_hnrOn-pTHQ
How do you stop such a monster when one arm breaks??
You wait until it stops blowing outdoors.
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Colour been added to the blades. :D
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I have been gas welding to make final pieces on my test turbine.
Portable actuator rods were the last item to be forged.
These steel rods keep the thing on the ground.
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Ah yes, to see more clearly... Thanks for posting : )
[attach=1]
[attach=2]
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Thanks for correcting his gamma settings.
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Thanks for correcting his gamma settings.
:o
Yes lightness does good to the clarity.
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Electric cables cut to the right lenght....and fitted.
[attach=1]
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Another angle to it.
[attach=1]
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The electric circuit consists of 3 car headlight lamps.
[attach=1]
[attach=2]
Stripe coding allows me to find the right leg when assembling the systen outdoors for tests.
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All systems are now...GO !
[attach=1]
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Almost got it running.
[attach=1]
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They shoreline waves looks like you have a nice steady wind at about 3 m/s?
Should be a nice test.
Cheers
Bruce S
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They shoreline waves looks like you have a nice steady wind at about 3 m/s?
Should be a nice test.
Cheers
Bruce S
I had enough time yesterday to complete the first test.
Legs are too weak..it starts to oscillate at 350-400 rpm.
I have to reinforce them.
Keeps turning at 2 m/s...9-10 m/s seem to be right now a bit too much.
[attach=1]
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After several modification and tuning and some soldering I am ready for a new round with my VAWT.
[attach=1]
[attach=2]
[attach=3]
Legs are reinforced and a new kinda vibration is fought with a trim tab....apparently I managed the make little wash out on the other wing...5 mm most ...at tip.
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.it starts to oscillate at 350-400 rpm.
If you increase the load from the electrical generator you can cause the VAWT to slow down.
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.it starts to oscillate at 350-400 rpm.
If you increase the load from the electrical generator you can cause the VAWT to slow down.
Yes that is acknowledged. There was a failure in a connection in "the light box"..no connection...I had to buy a new soldering tool to get it straight.
The emergency shut down worked fine in 10 ms wind...as I have no disc brake in it.....I have to short cut the generator and use broom to slow down the arm that wings are attached to...then grab the wing with hand. If it was any bigger I could not manage it by myself.
I can make new wings next winter....but for now I have to go forward with what I've got.
[attach=1]
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There is a shadow in paradise now....the rpms halved after all the antiresonance systems that really did cause it to vibrate less ( they nearly vanished ).
The trim tab was possibly a "fatal" error. But one of the bearings seemed afterwards to be in a tilted angle...so many things may have caused it...done 4 mods last nite. I hope it all helps.
[attach=1]
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After lot of balancing and reinforcing I got 449,3 RPM reading, but still no electricity. Next I will open up the generator.....and do what has to be done.
[attach=2]
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[attach=4]
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Sorry to disappoint you all, but Planet geared gene system seems to be too heavy for my wingsystem. All summer long I have had to reinforce the tower structure to keep it real steady. I accomplished at least that. I will try without the gear once more then I am done. After that new wings and the moment arm have to be constructed, but 30% or better efficiency is hardly available here.
[attach=1]
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i thought you had abandoned the planetary gear drive back at reply #27
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I did start testing without it......but as nothing happened I put the gear back...not knowing I had loose wires in the system that prevented electricity go as planned in the system.
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Okay..I purhased a tool to make spars for the next set of wings.
[attach=1]
I still do have a long way ahead to reach what I am after...which is sustainable living.
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you can do a lot with a table saw.
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you can do a lot with a table saw.
Smoother cuts than with a chainsaw too 8)
Bruce S
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you can do a lot with a table saw.
Smoother cuts than with a chainsaw too 8)
Bruce S
I also got me a router as I could not afford the laser cutter.
[attach=1]
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I tested my system at 15 m/s wind ( in gusts )...and 13 m/s average wind.
Halogen shines brite....so it does create electricity.
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Hi all and happy new year 2021 !
My both computers died before christmas. Thus lost the contact too.
I did test further.
I have some plans to re-tune it again.
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please carry on
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Welcome back.
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Welcome back.
Thanks folks...good to be back here.
This is the last test in 2020 at 16-18 m/s wind...some damage did occur.
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Okay dames and dudes !
I determined that my wind turbine tests failed as the work quality was poor, turbine ( affecting area ) too small for the hard/heavy geared turning generator and in some areas too weak wood quality was present.....and also some details were far from adequate for a fast turning turbine.
I can get away with my tower, but wing and the middle "shaft " have to be redone...they are now ready for cutting.
Might take a month or two.
;)
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You never know what you're going to learn, but when you expose a new machine to the forces of Nature, you can be sure that she will try to teach you a lesson.
Happens to all of us!
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You never know what you're going to learn, but when you expose a new machine to the forces of Nature, you can be sure that she will try to teach you a lesson.
Happens to all of us!
Yes Sparweb...it is a terrible feeling to realize that your first serious attempt was only meant to teach you. ;D
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double
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Yes Sparweb...it is a terrible feeling to realize that your first serious attempt was only meant to teach you. ;D
But it was a pretty first attempt. One of the best looking projects.
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"Failure is the mother of all invention!"
Have to fail before you fly!
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harnessing the wind .
oh yea, that's so easy .
ha ha ha
:-\
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What is intriguing is the fact that if I increase the rpms and make better aerodynamics that allow higher rpms....the g-forces become stupendous...especially if the generator fails or is not on. Stress loads on the wings are beyond any chart where they ought to withstand them stresses.
:P
I guess this is the risk I have to take. ;)
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Stress goes up with RPM squared. Gotta love it!
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you can do a lot with a table saw.
Makes a helluva noise. ;)
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This is the way I lengthen the legs by ½ a meter.
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What is intriguing is the fact that if I increase the rpms and make better aerodynamics that allow higher rpms....the g-forces become stupendous...especially if the generator fails or is not on. Stress loads on the wings are beyond any chart where they ought to withstand them stresses.
:P
I guess this is the risk I have to take. ;)
I remember reading you had this VAWT up to 900RPMs or something like that? Why are you trying to get such high RPM? More RPM = less efficient, more drag, more friction, etc. You want RPM to be as low as possible to extract maximum energy from the wind.
For instance the Department of Energy tested VAWTs in the 80s and their systems ran between 15 and 35 RPM maximum. 35 RPM not 900+!
You VAWT can only light up a halogen lightbulb at these high RPMs. Have you actually tried to pull a real load from this VAWT and try to charge a battery or something? Very cool project you know, just....don't understand the point.
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Yes hello E1000 !
My vawt is a really small unit with just 300 watt capability.
I am not aiming at 900 rpm...it just happened with the smaller system displaying different proportions.
I am still learning...solidity was wrong on SN3...thus I need to make SN4.
There went really many things hayward on SN3 at high winds. I needed to digest all the info over the winter.
There are many features in this VAWT which could make it a winner....if I get the proportions and manufacturing quality in to par.
I just cleaned the work shop....and prepared new generator to be ready to assemble in the system.
I had 2 wisdom tooth removed and had to take penicillium....and now getting my vitality back.
I just have to pray that no new nasty phenomena would appear while testing.....I am starting to be pretty broke by then......if not already.
Absolute low has been to get stuck in the sand in the Island where there are good winds always.
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"Failure is the mother of all invention!"
Have to fail before you fly!
Yes yes yes !
I just don't wanna fail very many times.
Someone here said my foil is a failure...I think I agree now.
I did some work with XFLR-5 to mend it.
Usually only foil you see in VAWT is NACA 0012.
Fire away and tell is it still better than this displayed in polars.
I see it has an advantage still in some areas.
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you can do a lot with a table saw
[attach=1]
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you can do a lot with a table saw
(Attachment Link)
I HAVE HAULED 3 THICKNESS OF PLYWOOD AND 650 GRAMS OF BOLTS AND NUTS and HALF A CUBIC METER OF STYROFOAM TO MY WORK SHOP.
Sorry caps lock !
My foils is not like GOE displayed. But I do dare to say it rocks ( if XFLR-5 is not broken ) ! ;)
[attach=1]
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Usually only foil you see in VAWT is NACA 0012.
Fire away and tell is it still better than this displayed in polars.
I see it has an advantage still in some areas.
(Attachment Link)
Actually, the US National Renewable Energy Laboratory did extensive testing and found the Somers S824 was the most efficient airfoil to use on their multiple different VAWTs.
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Usually only foil you see in VAWT is NACA 0012.
Fire away and tell is it still better than this displayed in polars.
I see it has an advantage still in some areas.
(Attachment Link)
Actually, the US National Renewable Energy Laboratory did extensive testing and found the Somers S824 was the most efficient airfoil to use on their multiple different VAWTs.
Cool...I have to check it out. Thanks ! :
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Interesting thing: https://www.researchgate.net/profile/W-Sheng/publication/29816886_Applications_of_Low-Speed_Dynamic-Stall_Model_to_the_NREL_Airfoils/links/00b495363babd11a75000000/Applications-of-Low-Speed-Dynamic-Stall-Model-to-the-NREL-Airfoils.pdf
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If you want to build a good VAWT the attached document is required reading: energy.sandia.gov/wp-content/gallery/uploads/SAND2012-0304.pdf
Dyamic stall is how you keep your VAWT from tearing itself apart ;)
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If you want to build a good VAWT the attached document is required reading: energy.sandia.gov/wp-content/gallery/uploads/SAND2012-0304.pdf
Dyamic stall is how you keep your VAWT from tearing itself apart ;)
Yes stall is very viciuos if not treated right in a VAWT.
My VAWT is more related to the McDonnell Aircraft design (of 1980) than Sandia types of non-articulating VAWTs.
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Yes stall is very viciuos if not treated right in a VAWT.
My VAWT is more related to the McDonnell Aircraft design (of 1980) than Sandia types of non-articulating VAWTs.
Yep and the McDonnell Douglas VAWT was a commercial failure and the Sandia designs are not. The document explains that straight blade VAWTs like yours need to be excessively heavy because of the forces. A VAWT like the Sandia types can be made exceptionally lightweight because the blades can be loaded in tension and they naturally stall before ripping themselves to shreads.
Your VAWT is not making much power and it keeps shredding itself to pieces. I thought maybe you'd be interested in solving those problems...
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Yes stall is very viciuos if not treated right in a VAWT.
My VAWT is more related to the McDonnell Aircraft design (of 1980) than Sandia types of non-articulating VAWTs.
Yep and the McDonnell Douglas VAWT was a commercial failure and the Sandia designs are not. The document explains that straight blade VAWTs like yours need to be excessively heavy because of the forces. A VAWT like the Sandia types can be made exceptionally lightweight because the blades can be loaded in tension and they naturally stall before ripping themselves to shreads.
Your VAWT is not making much power and it keeps shredding itself to pieces. I thought maybe you'd be interested in solving those problems...
I am very interested solving my problems...and I have been doing it all day even today.
Sandia is not articulating.
It is true that many articulating ones have failed ( or did they ? )...Pinson, Bühler ( Roman ) ...etc, but ANEW in Poland took another road and claims are stupendous.
Why McDonnell did not carry on is a mystery..they had funding for another 4 years in 1982. Oil Crisis ended....and their system was very promising albeit not quite ready in 1980....maybe a bit too complicated.
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Yes stall is very viciuos if not treated right in a VAWT.
My VAWT is more related to the McDonnell Aircraft design (of 1980) than Sandia types of non-articulating VAWTs.
Yep and the McDonnell Douglas VAWT was a commercial failure and the Sandia designs are not. The document explains that straight blade VAWTs like yours need to be excessively heavy because of the forces. A VAWT like the Sandia types can be made exceptionally lightweight because the blades can be loaded in tension and they naturally stall before ripping themselves to shreads.
Your VAWT is not making much power and it keeps shredding itself to pieces. I thought maybe you'd be interested in solving those problems...
Begin Moderator MODE
E1000:
Instead of criticizing Topspeed's efforts and each answer from Topspeed; how about you show what you've built and explain why.
I've watched this thread for a bit now and TopSpeed is both building and learning.
ALL I've seen from your posts is criticism. SO instead of constantly saying why this won't work or here's what you did wrong . Show what you've done, which would to include details.
You're not yet at the number of posts that will allow you to post pictures , BUT anyone of the Moderators or Admins can assist with them if they are relevant to this post.
I also highly suggest you go to the very beginning of his posts on this and read them so you can have a better understanding of what he's doing, learning and accomplishing. Before you send another criticizing post.
End Moderator Mode
Bruce S
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Yes thanks Bruce...learning curve has to be pretty steep...otherwise you'll "die" in business sense.
I checked my SOLIDITY on my recent tests seems that the hot system had .4 and this latter .49....so .49 was too much.....where as .40 was really phenomenal.
This is also verified by the literature.
https://www.sciencedirect.com/science/article/pii/S0360544218319704 .......link explains nc/d = .36 as a good in gaining high Cp.
Where as some even mention solidity of 1 to be ok ?
https://www.hindawi.com/journals/isrn/2012/528418/
Some even cannot count the solidity like others do: https://eprints.whiterose.ac.uk/95454/5/Revised_manuscript-R3_for%20Upload.pdf
But when deciphred it in indicates solidity of 0.52....which is way over the top.
All this also explains why McDonnell Aircraft Giromill failed.
https://wes.copernicus.org/preprints/wes-2019-98/wes-2019-98.pdf
It had solidity of 0,2 only.
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Hello everyone !
I give a brief update on the advancement of my 2 wing darreius type pitch controlled system.
The structure connecting the wings is almost ready. It is almost 1 metre wider ( longer ) than the previous had with similar generator. This has been a bit stressful since the bending was much more than I expected in the system. I had to reincorporate the wood composite that I had developed 2016 into it and some V-shaped struts from aluminium to keep the loads and stresses in a limit. The bending as such is not a problem, but the mechanism cannot work if there is too much of it. All this is learning by doing...certainly ( almost ) avoidable if you have a good enough structural engineer on it.....but the bending is also visible on aeroplane wings....before and during the flight...main thing is that it is firm in all winds and speeds....and is smooth and light(ish ?).
Now a challenge is two make the 2 wings light ( and yet strong ) enough that the bending does not become an issue.
Hope you all have had a good summer. ;) :)
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I'm excited to see a video of it!
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The best part is the fun you're having. Thanks for sharing.
If bending's a problem, have you considered a diagonal brace?
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The best part is the fun you're having. Thanks for sharing.
If bending's a problem, have you considered a diagonal brace?
I have used 3 innovations ( ~means ) to address the issue. Diagonal braces ( struts ) ....wood composite ( 1400 kg/m^3 ) and last but not least a pre stressed system....which allowed to get rid of the bending now once and for all.
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Yellow stuff is wood composite (compreg).
At least you get use many tools in this.
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I like the shine in the wood finish!
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I like the shine in the wood finish!
How about the shine on "refurbished" old wings without winglets ?
They look raw...as I did not paint them again...I am getting rid of extra weight to make it happen.
New wings will take weeks to build.
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I hope to get shiny glass like surface on this...so it glides effortlessly in the wind.
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Haha.
Perhaps a more reasonable point of view is to get it working first, then make it pretty later.
Not all of us do it that way around...
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Haha.
Perhaps a more reasonable point of view is to get it working first, then make it pretty later.
Not all of us do it that way around...
Yes...as one confronts a phenomena and tries to solve a problem within...the main facts start to appear in your head and everything you do is just to trying to make it work in reasonable time frame.
I really like the shine on this.
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I also started to do another set of high wind wings for it.
Instead of 12 % thick I decided to go to 14 % thick...here are the polars of it...on green color.
Also very high lift with minimal drag.
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Router makes neat foils.
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Vestas's public speeker Rosie tells us about VAWTs.
https://www.youtube.com/watch?v=ldt405jIR0E
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Using a laser cutter would have speeded up this enough, but as it is....I have been using grinder with table saw blade on these...to get the spars into the right place. ???
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Using a laser cutter would have speeded up this enough, but as it is....I have been using grinder with table saw blade on these...to get the spars into the right place. ???
(Attachment Link)
There is also a jig redied for the wing assembly.
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Looks good.
IMHO, good work and smooth surfaces get you mich more than any airfoil shape, at the WT scale - especially rhe VAWT scale.
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Thanks Spar Web,
Some more progress.
Here is a status of today.
Older yellow wing is visible on the background.
Monent arms are also now 50 cm ( 1 m together ) longer than before.
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Modest advancement. ;)
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This really reminds me of the glider competition I joined in college. We made an aircraft glider with a 3 meter wingspan to carry a heavy payload. The competition was to keep the glider aloft for as long as possible. The wings of that glider looked a LOT like your VAWT wings!
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This really reminds me of the glider competition I joined in college. We made an aircraft glider with a 3 meter wingspan to carry a heavy payload. The competition was to keep the glider aloft for as long as possible. The wings of that glider looked a LOT like your VAWT wings!
Yes thanks again.
I am putting all my effort to make this as perfect as I possibly can without industrial level tools.
This has to be fast too...otherwise it will stall at high winds speeds because of the TSR demand.
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This really reminds me of the glider competition I joined in college. We made an aircraft glider with a 3 meter wingspan to carry a heavy payload. The competition was to keep the glider aloft for as long as possible. The wings of that glider looked a LOT like your VAWT wings!
Reminded me of my RC airplane days and the 6' Piper Cub wing I built(and rebuilt after crashes!) an aluminum main spar ran the full length then the rest of the wing was built off of it
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That's still the norm with many homebuilts, Mary.
Big aluminum tubes with relatively thin wall are a simple starting point, then the ribs slide down from the end.
Some get fancy, and use carbon-fiber spars instead. I'm not so keen on that because cheap CF tubes are very porous.
Either way, the tube fits into a round socket and voila the wing disassembles for transport on a trailer.
I still see a lot of these at the EAA airshows. I don't go as often as I used to, but funny thing, the true classics are still there.
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That's still the norm with many homebuilts, Mary.
Big aluminum tubes with relatively thin wall are a simple starting point, then the ribs slide down from the end.
Some get fancy, and use carbon-fiber spars instead. I'm not so keen on that because cheap CF tubes are very porous.
Either way, the tube fits into a round socket and voila the wing disassembles for transport on a trailer.
I still see a lot of these at the EAA airshows. I don't go as often as I used to, but funny thing, the true classics are still there.
Simplicity is one goal.
Unfortunately the 34 m/s wind needs TS of 490 km/h speed for the wing...it cannot be a Piper Cup wing anymore.
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What's it going through in one rotation at that velocity, 2-3g then the same inversed? Piper Cub wings can handle it. :)
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What's it going through in one rotation at that velocity, 2-3g then the same inversed? Piper Cub wings can handle it. :)
Old straight wing clocked 300 Gs......counting using weight and speed on a circular path.
By old I mean the green smaller prototype...from 2018. The yellow wing system suffered from being too big in solidity and having too big generator for the size. I fixed this now by increasing the wind capture area almost 3 x.....and dropped the solidity by 35%....or thereabouts.
I figure the new can do 500 Gs....computational Gs.
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I have put a lot of effort to keep my work space clean lately...it also rises the spirits there when everything is not covered with 1 mm layer of fine grain dust.
Here the aluminium dust is sucked away by a new vacuum cleaner.
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I am one step further on my 4th test wind mill.
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Looks nice - will there be a longeron at the trailing edge? I don't see it there yet.
If you are avoiding that, to make a sharp trailing edge, I can show you some RC model airplane tricks to keep the edge from wrinkling.
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I have 1 mm plywood covering...no need for the longeron there.
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This looks awesome. Very nice work indeed.
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Those are some nice looking support structures. I'm assuming the skin is going to help with the bending forces once this thing really gets spinning.
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Yes skin is very important structural component in this.
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Yes skin is very important structural component in this.
What is your projected rpm? I wish I could find the video again, and I am sure some of you have seen it, but I saw one made on the other side of the pond, that was huge. It had to have been 20ft across and had 5-8 blades or so, I understand they were promoting their product design, but they did a good job. They had it mounted on a trailer and moved it to several spots and the thing just spun and spun. It was as close to a constant velocity (in different situations) vawt as I had seen to date. (outside commercial ones). It was part of my whole design process. How I just want one that sits there and turns if the wind is 10 or if it is 25. That and watching the big hawts around me do that, made me think of the turtle and the rabbit race. Sure maybe I can't put out x amount per day, but averaged over the 168 hours in a week, I am hoping I can compete with a good hawt, if not edge above it in the long run.
The slower it spins the less important the selection of blade skin is. Don't you think?
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What is your projected rpm? I wish I could find the video again, and I am sure some of you have seen it, but I saw one made on the other side of the pond, that was huge. It had to have been 20ft across and had 5-8 blades or so, I understand they were promoting their product design, but they did a good job.
Wow this is a 7 page post
I have some personal projects that I'm working with on external combustion will post these.
Cooking some shrimp tonight. My camera needs to be replaced, will get a new one.
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What is your projected rpm? I wish I could find the video again, and I am sure some of you have seen it, but I saw one made on the other side of the pond, that was huge. It had to have been 20ft across and had 5-8 blades or so, I understand they were promoting their product design, but they did a good job.
Wow this is a 7 page post
I have some personal projects that I'm working with on external combustion will post these.
Cooking some shrimp tonight. My camera needs to be replaced, will get a new one.
I need to hurry up and get this project done, as I have a couple more in mind as well. It is supposed to get up to 40 here in a day or two, I think I will use that day to get some wood cutting and such done out in the shop.
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Right- on.
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Yes skin is very important structural component in this.
What is your projected rpm? I wish I could find the video again, and I am sure some of you have seen it, but I saw one made on the other side of the pond, that was huge. It had to have been 20ft across and had 5-8 blades or so, I understand they were promoting their product design, but they did a good job. They had it mounted on a trailer and moved it to several spots and the thing just spun and spun. It was as close to a constant velocity (in different situations) vawt as I had seen to date. (outside commercial ones). It was part of my whole design process. How I just want one that sits there and turns if the wind is 10 or if it is 25. That and watching the big hawts around me do that, made me think of the turtle and the rabbit race. Sure maybe I can't put out x amount per day, but averaged over the 168 hours in a week, I am hoping I can compete with a good hawt, if not edge above it in the long run.
The slower it spins the less important the selection of blade skin is. Don't you think?
Since the radius is now greater and generator has a gear I need only 100-200 rpm.
Next I am onto the wing tips. That will expand the span by 10-15 %.
[attach=1]
The 1 mm ply covering with surface handling will double the weight of the wing.
It is just under 1,5 kg now ( at 3 lbs ).
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I think we are all excited to see it up and turning in the wind.
What are you going to seal it with to keep moisture out? 3 pounds is lightweight for a blade that size, so you have some options when it comes to trying to preserve them from water.
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I think we are all excited to see it up and turning in the wind.
What are you going to seal it with to keep moisture out? 3 pounds is lightweight for a blade that size, so you have some options when it comes to trying to preserve them from water.
I use normal varnish or such coating lacquer kinda glossy liquid that makes the surface slippery too. Hefty amounts of it too...so that it look like glass when dried up.
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I think we are all excited to see it up and turning in the wind.
What are you going to seal it with to keep moisture out? 3 pounds is lightweight for a blade that size, so you have some options when it comes to trying to preserve them from water.
I use normal varnish or such coating lacquer kinda glossy liquid that makes the surface slippery too. Hefty amounts of it too...so that it look like glass when dried up.
Yeah waterproof means different things depending on where you are. Here in the US, you can build an untreated pine fence in the south west and it will last for years. In other areas, it will rot away in a year.
That is the thing about building these things, there is a million ways, because each one of us had different circumstances to deal with.
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About 6 years ago I was talking to a boat builder in southern Finland who claimed that wooden boats last forever as long as the surface stays unbroken....or the structure in general.
Wonder if the poor maintenance or the holes for attachments are the cause for a rot.
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About 6 years ago I was talking to a boat builder in southern Finland who claimed that wooden boats last forever as long as the surface stays unbroken....or the structure in general.
Wonder if the poor maintenance or the holes for attachments are the cause for a rot.
Well he might be right. I have seen lots of old wooden boats. I mean hey look, if wood rotted away so easy, we would not be living in wooden houses. My grandparents always said, keep a good roof on it and it painted and it will last forever. People just do not like the work of maintaining things these days.
I put a couple coats of linseed oil on my stator mold today and I was thinking how my dad who owned semi trucks used to linseed the wooden decks of the flatbed trailers. Granted that is a hard wood and not pine or spruce, but really it is just a matter of saturation when talking weather proof and not strength. We always did it in the middle of summer when it was hot. Idk maybe because the pores of the wood open up in the heat? (I brought my mold in the porch where it is warmer for the second coat).
Strange how we remember lessons that we did not even know we knew.
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Be aware that rot is microbe activity, something much slower in Finland than at the equator.
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Thank God the clamps were invented before my time.
[attach=1]
[attach=2]
[attach=3]
[attach=4]
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I am starting to think you enjoy the whole blade building process. Lol. The closer I get to when I will get to that part and start buying stuff to do it with, the more nervous I get.
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Yes I enjoy it very much as each time I have a problem I just stop it....until I have an answer how to go forward. ;)
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HAHA
You are the clampmaster!
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Clamps are still in need, but I have to advance one surface at a time.
Applying pressure on the skins.
Wing tips are almost ready.
[attach=1]
[attach=2]
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I am currently finishing the 3rd wing half....two are raw finished...in the pic ....and wing tips painted.
[attach=1]
Yellow one below is the old wing.
[attach=2]
Here is the third one receiving pressure.
[attach=3]
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Impressive, I can't wait to see it flying!!
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Thank you Astro....I blew the last attempt on this....now I am trying to keep it dead center and use all the knowledge and concentration I possibly can.
[attach=1]
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I counted that this blade/wing has same aspect ratio than the Bald Eagle.
https://avianreport.com/bald-eagle-wingspan-versus-birds-prey/
[attach=1]
I reckon it is even steven 8.
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Even if your project fails to hit your metrics, you definitely win my vote for Best in Show.
Once again you prove your unmatched craftsmanship.
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Agreed. Fab fab skills! Wish I had some!
Rgds
Damon
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Wow !
I thank you Astro, Matt and Damon !
I try my best now since I know these take a lot of time to tune everything...the summer here is short...and the world needs clean energy.
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Some advancement.
[attach=1]
SLAVA UKRAINI ! ;)
[attach=2]
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I found this very informative: https://link.springer.com/article/10.1007/s40095-014-0129-x
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So its basicallt saying shorter and wider is better due to a combination of less drag and better leverage. I'd be worried about breaking the sound barrier if you get too wide. Some of those barrel-based VAWT drag units already approach 500 rpm in 40 mph winds. I'd hate to see those aerofoils hitting four times that.
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This Agile Wind VAWt was interesting.
It broke at 20 m/s.
https://www.agilewindpower.com/en
https://www.verve.vc/portfolio/agile-wind-power/
[attach=1]
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Winter still here...snowed yesterday.
I have to use ( a lot of ) filler to make this aerodynamic shape work.
[attach=1]
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All these mishaps are due to scaled up size and sweeping the wings.
I ought to have used more wing foils, but I have to patch up all disruptions in aerodynamic flow. Otherwise this whole enterprise is completely useless.
I used here saw cutter and D3 glue to patch the two wing tips were the alignment of the plies was wrong.
All these will end up in more weight and worse efficiency, but ...I have to try this now.
[attach=1]
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I am ready now...looking for a funding.
[attach=2]
[attach=3]
[attach=1]
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I can't wait!
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Wow this feature is working. super happy.
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Short update:
I have made so far 2 attempts to run the 4th prototype.
First attempt was made in early June...and 16 items were missing.
Second yesterday..very close one..only the tool used to tighten the wings was not able to move the needed 1/6 rotation inside the wing.
I have to do some readjusting to it to make it work.
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They make ratchets that are short stroke... just for that type of need. I make sure to have one in 3/8 drive just in case.
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They make ratchets that are short stroke... just for that type of need. I make sure to have one in 3/8 drive just in case.
I gotta get me one tomorrow...thanks Mary B. ;)
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Okay...here we go..this one left is 47% thinner where it counts most....and gets the job done.
[attach=1]
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Careful not to let this happen to you:
[attach=1]
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That was a good one.
I was in the Shark Island and the owner of the beach where I was came by to say that looks like a hard sort of sport. ;)
It sorta is...I have tinkered now 8 years on my device...and I haven't actually received anything from this.....but lost time and money.
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Time and money is a pretty common cost of tinkering. Unless I can find a practical application for stuff I build, it doesn't get made or it gets made from junk I have laying around.
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Time and money is a pretty common cost of tinkering. Unless I can find a practical application for stuff I build, it doesn't get made or it gets made from junk I have laying around.
I don't mind the tinkering, but I am afraid all this works gets blown into wind...if the workman ship or the low Re-number won't take me where I am trying to be.
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Man once the main pump is primed there you go- can pressurized "we can make steam"
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I want to upload video "to the forum" we can have our own youtube here :)
We need TechAdmin to get a way with this.
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There were some critical moments there, but now solid applications
we need to push TechAdmin on this I want to post video on the site.
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Your technical demands jump quite a lot with video. It will take all the previous bandwidth used for the month to serve a 5 minute video at 4k. And unless you have robust hosting, that video experience will suffer from serious buffering. Early video hosts had a lot of challenges to overcome.
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@topspeed Tempted to give you "Clampmaster" as custom title, you surely earned that and a few others, including blade crafter and such ;D
@JW it's best to post videos to YouTube, as unlisted if people want, then link them from here. 3 reasons for this: 1) Storage (videos are heavy on storage) 2) Bandwidth (same, but bandwidth is more expensive than storage) 3) technical reasons (not many of those systems around and we will have to do a giant update in some time anyway, I'll bring it up in admin board sometime).
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Changing an alternator on this Buick today, was going to hot swap it. But will disconnect the battery its in the trunk. Surprised at the batt capacity. there is a tonn of electronics ,better to disconnect the bat.
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This project is taking me to funny roads...I mean I just got me an old ( practically for free ) V-8 powered Chevy Van...just to be able to get it to nature for the tests.
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This project is taking me to funny roads...I mean I just got me an old ( practically for free ) V-8 powered Chevy Van...just to be able to get it to nature for the tests.
I had to give up on than Chevy...too risky at 180 000 miles on the meter. It would have been perfect with solar panels and chemical toilet.
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This project is taking me to funny roads...I mean I just got me an old ( practically for free ) V-8 powered Chevy Van...just to be able to get it to nature for the tests.
I had to give up on than Chevy...too risky at 180 000 miles on the meter. It would have been perfect with solar panels and chemical toilet.
If it was well maintained then it had another 180 left.
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This project is taking me to funny roads...I mean I just got me an old ( practically for free ) V-8 powered Chevy Van...just to be able to get it to nature for the tests.
I had to give up on than Chevy...too risky at 180 000 miles on the meter. It would have been perfect with solar panels and chemical toilet.
If it was well maintained then it had another 180 left.
Yes the owner said it consumes 26 liters/100 km when pulling a trailer. It is still an option...I just have to use my old car with a roof rack...which is not very reliable system.
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I'm with MattM on this one!
Check the engine numbers, see if it's a 4-bolt main style, if there's no tick tick tick when you rev-up the the engine then you're pretty much assured it's okay.
What sized V-8? small block of big block?
My 1970 Chevy Impala lasted through 201K small block 350 4-bolt main with a 4-barrel carb (4-barrels actually got better mileage due to small primaries).
Cheers
Bruce S
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i have 350 chev 4 bolt main on my engine stand. wanting to rebuilt it ( yea , when i get the chance).
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I'm with MattM on this one!
Check the engine numbers, see if it's a 4-bolt main style, if there's no tick tick tick when you rev-up the the engine then you're pretty much assured it's okay.
What sized V-8? small block of big block?
My 1970 Chevy Impala lasted through 201K small block 350 4-bolt main with a 4-barrel carb (4-barrels actually got better mileage due to small primaries).
Cheers
Bruce S
5.7 litre...1989 model.
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Ok folks !
I was able to run my test turbine no 4 today in Lappland...on the coast...of Bothnic sea in the parish of Simo.
All the lights were burning brightly at average 4-5 m/s wind. But it kept rotating even at 3 m/s wind...with less bright halogens lights.
This was a big relief to me as I wasn't sure if all my corrections were succesfull...but they were.
The owner of the property helped me to rise the tower as it would have been impossible other wise.
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sounds like some congratulations are in order
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Well done!
Rgds
Damon
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Yes folks...thank you.
The tower needs reinforcing again.
[attach=1]
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Ya im impressed with this. https://www.fieldlines.com/index.php/topic,150469.msg1060275.html#msg1060275
I have a seat on Solidworks 2016. nice....
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Ya im impressed with this. https://www.fieldlines.com/index.php/topic,150469.msg1060275.html#msg1060275
I have a seat on Solidworks 2016. nice....
It is impressive.
[attach=1]
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Bravo!
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Yes I was able to pinpoint, after what I saw, few defects in the system.
Those are now fixed.
Now I am going to go test it again.
Tower had 2 weak points....those are now ok.
Wings had some flaws too..that has been taken care of as well.
[attach=1]
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Heavy duty like a boat anchor. O0
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Heavy duty like a boat anchor. O0
Yes...and I have to use it now on revitalized 3rd prototype since I was able to destroy the 4th prototype on the second test attempt.
I really blew it...I forgot to connect the electrical wires from the generator in a hurry in a high wind. It needs no bigger mistake.
Run away event taught me a lot and wings are still repairable, but the torque arms were broken on two places...broken loose.
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Looks very innocent from afar.
[attach=1]
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ouch . you testing your machine away from home so your not able to give a secure base. i think you need to drive some some steel rods into the ground and attach your support to them. maybe a flat plate on the end of those legs with bags of sand or concrete blocks. don't lose heart.
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ouch . you testing your machine away from home so your not able to give a secure base. i think you need to drive some some steel rods into the ground and attach your support to them. maybe a flat plate on the end of those legs with bags of sand or concrete blocks. don't lose heart.
I had a 10' satellite dish way back when when C band TV was a thing. I had it mounted on crisscross 6x6 timbers with a pile of concrete blocks out at each end. Survived 80mph winds! And a 10' dish is a LOT of wind load!
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Sorry to see it slammed over!
Can you pound some pickets into the earth to secure the legs?
Something stronger than tent pegs.
This assumes it's not a rocky shore!
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ouch . you testing your machine away from home so your not able to give a secure base. i think you need to drive some some steel rods into the ground and attach your support to them. maybe a flat plate on the end of those legs with bags of sand or concrete blocks. don't lose heart.
Problem was that there were steel rods...but as I knew there is no way to stop it as I only had shortcut brake I tried to haul it in to the forest, but as it was arduous I tried to get a long branch from the forest to stop it somehow...and as the tower seemed to do ok without the rods...I went to get the branch...and as I came back close to the system it decided to fall.
I missed the ferry back home and I have to overnight in the island.
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"I missed the ferry back home and I have to overnight in the island."
i hope you brought some snacks for you surprise camping expedition.
would the owner of the property allow you to construct a secure base of some kind that your mill could lock into ?
so you don't have to transport, construct and tear down every time?
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Screw in anchors and ratchet straps. They come in all kinds of sizes... in that loose sand the bigger the vanes the better and they are easy to remove and do minimal damage to vegetation.
(https://cdn11.bigcommerce.com/s-zi19a7vf4e/images/stencil/1280x1280/products/1024/1951/TOSH0009__15037.1619555458.jpg)
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something i have been considering as far as a strong base . your testing area is very close to the sea. consider bringing empty plastic vessels along with you. as many as is required
when you set up the mill you could fill the vessels with sea water as a weight against the wind up ending your machine . when you finish the test you could just empty the plastic vessels and take them home .
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"I missed the ferry back home and I have to overnight in the island."
i hope you brought some snacks for you surprise camping expedition.
would the owner of the property allow you to construct a secure base of some kind that your mill could lock into ?
so you don't have to transport, construct and tear down every time?
Yes there is also plenty of sand.
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Screw in anchors and ratchet straps. They come in all kinds of sizes... in that loose sand the bigger the vanes the better and they are easy to remove and do minimal damage to vegetation.
(https://cdn11.bigcommerce.com/s-zi19a7vf4e/images/stencil/1280x1280/products/1024/1951/TOSH0009__15037.1619555458.jpg)
Those may not be so easy to implement on my system as they have to be erected rapidly for the tests.
[attach=1]
My failurre was to think that the H-Darrieus can be left unguarded without those spikes on the pic....in a stormy weather.
I was able to pull it up with a second prototype in 2019..in 14 m/s wind...as it had very little resistant on that day.. back then..I did put a halogen on instead it of the led light on recent tests. It did not much lesser the rpms...but some.
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Add a safety that holds the arms from turning until you pull it out!
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Add a safety that holds the arms from turning until you pull it out!
That is in order.
On the stiffening process of the tower I am adding a light but hopefully strong system to do it.
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Can't wait to see your new ideas.
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[attach=1]
It is all crisscrossing ! ;D
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I did quick test and saw that it does rotate at 2 m/s wind, but still need a new torque arm to replace the one that broke down in the recent mishap.
[attach=1]
This is awesome now...no bending at the 3,5 m/s peaked wind. Old system was already bending like mad.
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Just a quick update on this.
I have started last week the new moment arm that works with the blade actuator...and now I am working on an aerodynamic fairing for the moment arm. Should be ready by tomorrow.
Small difficulties has been...burned my leg with cooking oil and two machines stopped working yesterday..or day before. Now they are all fixed and leg seems ro recover as well.
Geeeesh ! ;)
[attach=1]
I hope to get back to operating the test rig soon.
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stay safe
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Yes I am trying ED1...it is getting very cold in here to test outside...took me 4 hours to set it up and 3 the next day to disassemble it.
I am getting now more rpms...but checks need to be made (8 of them). Some small anomalies occured after 5 hours of running time.
I was able to see the stars above in the island...in the city you cannot see'em.
[attach=1]
....and sand bags helped a lot !
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I am in process of making a three legged tower with longer aerodynamical part on top.
I run into phenomena that sorta compells me into to this route.
It is all due to aerodynamics.
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It is all due to aerodynamics.
What a drag.
;)
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I found this very informative: https://www.mdpi.com/2071-1050/14/5/2623
[attach=1]
The solidity plays an important role......along with the chosen airfoil.
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Here is the new tripod tower meterializing.
[attach=2]
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Here is the frame of the new fairing for the tower..stabilising the flow after the tower...for the tests.
[attach=1]
I am very happy I did this as the legs can be attached in hour faster than before...and the torque arm possibly 30 minutes faster than before.
This very crucial in test phase as the winter is nearing and the days are really short.
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More clamps and a new vice....and belt for the saw.
[attach=1]
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Can you ever have too many clamps?
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I have been loosing so many plastic ones that I needed more reliable ones.
G-clamp is the most reliable.
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Sorry to disappoint you all, but Planet geared gene system seems to be too heavy for my wingsystem. All summer long I have had to reinforce the tower structure to keep it real steady. I accomplished at least that. I will try without the gear once more then I am done. After that new wings and the moment arm have to be constructed, but 30% or better efficiency is hardly available here.
(Attachment Link)
New thicker spikes to keep it steady.
[attach=1]
5x2s about 1 meter long plates can be added to it..to carry boulders to prevent any movent of the tower.
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What is the ETA on the next test run?
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What is the ETA on the next test run?
I cleaned the car first time after 5 years of testing. I had to pay 50 € for my daughter for being a big help for two hours.
I had a new test site in mind.
First I have to check if that stuff even fits the car anyomore.
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For the next model ? :o ;)
https://www.youtube.com/watch?v=-Fll1N8wO2s
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I have watched this nice movie about the manufacture of helicopter rotor blades. These blades are very heayy because the airfoil is filled with massive iron rods and aluminium or iron pipes. These rods are covered with a 0.5 mm stainless steel skin which finally makes that the outside is a NACA 0012 airfoil. What I don't like is that the both sheet sides are glued together at the tailing edge. I would prefere welding but this requires a larger sheet thickness. I think that wind turbine blades with a constant chord and blade angle can also be made from stainless steel sheet. If the sheet thickness is chosen large enough, no internal structure is required. For a wind turbine one should use an asymetrical airfoil like the Gö 711. As helicopter, one needs a symmetrical airfoil because the rotor must be able to work as a wind turbine rotor if the motor fails. If the angle of attack is positive for helicopter use, it will be negative for wind turbine use.
Just today I have finished the design report KD 751 of the 3-bladed VIRYA-6.5S rotor which has a design tip speed ratio of 7. The blades of these rotor are made from a stainless steel sheet size 2 * 500 * 3000 mm which is curved into a NACA 711 airfoil. This rotor is an alternative for the rotor with wooden blades as described in public report KD 738. KD 751 isn't made public because this steel rotor should only be made by a professional company with sufficient knowledge and manufacturing equipment.
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Adriaan,
Can you clarify exactly which helicopter that was?
the airfoil is filled with massive iron rods and aluminium or iron pipes.
That's not even remotely similar to the helicopter blades I have worked on. Can you retrace your steps to that video you saw?
When helicopter blades are retired from service (they have a fixed life) they are destroyed by the maintenance facility by sawing them to pieces. I can't overstate the criticality of this action on the part of the maintenance facility - they can lose their permit to practice if they fail to disable or destroy parts that they retire from service. At least, that's normal practice in North America and I don't know if it's exactly like that elsewhere in the world. The objective is to prevent re-selling helicopters parts on the black market since they are extremely valuable (to some who think fatigue does not apply to them).
My point being (sorry for taking so long to explain) that I've seen many types of helicopters blades after being cut apart. They all have very similar cross-sections. The following is from the UH-1 "Huey". It's a screen capture from the manufacturer's overhaul manual.
[attach=1]
To be clear there is no pipe, because such products have nowhere near the accurate dimensional tolerance to be acceptable in a helicopter. The hollow sections are extrusions, and I expect these are machined/lapped after the extrusion process to ensure extremely tight tolerances before being assembled into the rotor blade. The nose block is a typical balancing mass that prevents oscillation. I've seen copper used since it's dense, chemically inert against aluminum, and has similar stiffness to aluminum. Mixing radically different materials (e.g. steel and aluminum) doesn't work so well on a helicopter rotor blade because they will deform and disbond under the combined change in length from both elastic stress and thermal expansion. So I would be surprised to see different types of metal in a helicopter rotor blade, except at the root end attachment where high-strength stainless steel is essential.
As helicopter, one needs a symmetrical airfoil because the rotor must be able to work as a wind turbine rotor if the motor fails. If the angle of attack is positive for helicopter use, it will be negative for wind turbine use.
Not true. Symmetrical airfoil is much easier to manufacture. The successor model to the blade pictured above (Bell 212) has blades with airfoil profile that varies from root to tip, and the tip is not symmetrical. The need for reverse flow is entirely true, as you say, but that doesn't commit helicopter designs to have symmetrical airfoils. The real limitation on the types of airfoils that should be used is the high variation of Reynold's Numbers where they must operate. The tip traveling forward is nearly at the speed of sound when it is flying forward, and on the rear-ward stroke it has nearly zero velocity. Each blade tip experiences this cycle on every revolution or the rotor.
I've been told many times that I should use old helicopter blades in my wind turbines. It's an interesting place to start, and I do have access to them, but they are designed to be so structurally strong that they would make an extremely heavy wind turbine rotor. And, it would be discouraging to repair blades that have been sawed apart by the shop before they can give them to me.
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I have watched the video which is given in the link of the post of Topspeed reply #270 previous to my post. It concerns a helicopter which is developed by an idividual so not by a well established manufacturer. I might be wrong about the need of a symmetric airfoil for a helicopter blade but using a symmetric airfoil for a wind turbine blade of a HAWT is a wrong choice even if manufacture would be easier. Asymmetric airfoils of the same thickness have a higher maximum lift coefficient and a lower minimum Cd/Cl ratio at the same Reynolds value.
Use of the Gö 711 airfoil (see public report KD 285) for a constant chord blade of a wind turbine made out of stainless steel sheet is rather simple because the lower side of the Gö 711 airfoil is flat over 97.5 % of the chord. So you have to develop a tool for curving of the upper side of the airfoil and then only bend the lower side 90° at the leading edge. Both sides are welded together at the tailing edge. The airfoil has to be closed at the tip otherwise it may work as an organ pipe and become very noisy.
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Adriaan,
Can you clarify exactly which helicopter that was?
the airfoil is filled with massive iron rods and aluminium or iron pipes.
That's not even remotely similar to the helicopter blades I have worked on. Can you retrace your steps to that video you saw?
When helicopter blades are retired from service (they have a fixed life) they are destroyed by the maintenance facility by sawing them to pieces. I can't overstate the criticality of this action on the part of the maintenance facility - they can lose their permit to practice if they fail to disable or destroy parts that they retire from service. At least, that's normal practice in North America and I don't know if it's exactly like that elsewhere in the world. The objective is to prevent re-selling helicopters parts on the black market since they are extremely valuable (to some who think fatigue does not apply to them).
My point being (sorry for taking so long to explain) that I've seen many types of helicopters blades after being cut apart. They all have very similar cross-sections. The following is from the UH-1 "Huey". It's a screen capture from the manufacturer's overhaul manual.
(Attachment Link)
To be clear there is no pipe, because such products have nowhere near the accurate dimensional tolerance to be acceptable in a helicopter. The hollow sections are extrusions, and I expect these are machined/lapped after the extrusion process to ensure extremely tight tolerances before being assembled into the rotor blade. The nose block is a typical balancing mass that prevents oscillation. I've seen copper used since it's dense, chemically inert against aluminum, and has similar stiffness to aluminum. Mixing radically different materials (e.g. steel and aluminum) doesn't work so well on a helicopter rotor blade because they will deform and disbond under the combined change in length from both elastic stress and thermal expansion. So I would be surprised to see different types of metal in a helicopter rotor blade, except at the root end attachment where high-strength stainless steel is essential.
As helicopter, one needs a symmetrical airfoil because the rotor must be able to work as a wind turbine rotor if the motor fails. If the angle of attack is positive for helicopter use, it will be negative for wind turbine use.
Not true. Symmetrical airfoil is much easier to manufacture. The successor model to the blade pictured above (Bell 212) has blades with airfoil profile that varies from root to tip, and the tip is not symmetrical. The need for reverse flow is entirely true, as you say, but that doesn't commit helicopter designs to have symmetrical airfoils. The real limitation on the types of airfoils that should be used is the high variation of Reynold's Numbers where they must operate. The tip traveling forward is nearly at the speed of sound when it is flying forward, and on the rear-ward stroke it has nearly zero velocity. Each blade tip experiences this cycle on every revolution or the rotor.
I've been told many times that I should use old helicopter blades in my wind turbines. It's an interesting place to start, and I do have access to them, but they are designed to be so structurally strong that they would make an extremely heavy wind turbine rotor. And, it would be discouraging to repair blades that have been sawed apart by the shop before they can give them to me.
Here is a good look at them ( helo blades): https://www.youtube.com/watch?v=q_jbI1JeHc8
Incredible homebuilt contra blade system: https://www.youtube.com/watch?v=gAQ6uM_firQ
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I have watched this nice movie about the manufacture of helicopter rotor blades. These blades are very heayy because the airfoil is filled with massive iron rods and aluminium or iron pipes. These rods are covered with a 0.5 mm stainless steel skin which finally makes that the outside is a NACA 0012 airfoil. What I don't like is that the both sheet sides are glued together at the tailing edge. I would prefere welding but this requires a larger sheet thickness. I think that wind turbine blades with a constant chord and blade angle can also be made from stainless steel sheet. If the sheet thickness is chosen large enough, no internal structure is required. For a wind turbine one should use an asymetrical airfoil like the Gö 711. As helicopter, one needs a symmetrical airfoil because the rotor must be able to work as a wind turbine rotor if the motor fails. If the angle of attack is positive for helicopter use, it will be negative for wind turbine use.
Just today I have finished the design report KD 751 of the 3-bladed VIRYA-6.5S rotor which has a design tip speed ratio of 7. The blades of these rotor are made from a stainless steel sheet size 2 * 500 * 3000 mm which is curved into a NACA 711 airfoil. This rotor is an alternative for the rotor with wooden blades as described in public report KD 738. KD 751 isn't made public because this steel rotor should only be made by a professional company with sufficient knowledge and manufacturing equipment.
Even cars are clued together nowadays.
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especial aluminum body panels.
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especial aluminum body panels.
Yes adhesives have developed greatly during the last few years...or decades.
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I think the alloy was 5356, aluminum auto wheels. I'm just happy don't any more things to do with it.
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Stretched metal is very durable. You just need a way to reliably build in the stretching step. That way no glue is required.
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3m VHB tape, good stuff! I hung a picture with it 10 years ago, wanted to move it... had to saw the tape off with fishing line!
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Down side using sheet metal is that I don't have the tools it needs.
I ordered a wrong watt meter...new one is coming.
[attach=1]
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You can use 16" or 18" bar folders (about $20) for handforming and use light aluminum siding material for easy fabrication of a skin. Once you put even a tiny amount of stretch its extremely strong.
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What is the ETA on the next test run?
It was 4-3 days ago. Some connection issues and teething problems with the new tower and new bearings.....but successfull after all. Energy being produced still at 3 m/s wind.
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Strenghtening of the tower is underway.
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This is incredible mess where I am now.
No when I strenghtened the upper part of the tower with carbon fibre slabs from the inside...the legs started to go jello again...despite the struts and + wiring I added to them.
:o
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Too much weight or is the additive process weakening it?
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Too much weight or is the additive process weakening it?
There is only 1 kg extra weight...the tower part is now stiff....so it acts like a moment arm...to the rest of the tower......for those 3 legs. :)
Despite the wobbling it managed to run 20+ hours in a row...when creating electricity. There was no sign of fatique.
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Pictures or it did not happen. /wink wink
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[attach=1]
[attach=2]
[attach=3]
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That aerodynamical part on top looks quite a bit larger than before.
How did the new torque arm turn out?
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That aerodynamical part on top looks quite a bit larger than before.
How did the new torque arm turn out?
It may be unnecessasily heavy...but very sturdy now with bearings etc.
Blades are 26% bigger.
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I hate to be the one to say this, there's no way to know without a wind tunnel.
Im just saying building a 32ft dia wind tunnel is workable
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VAWT don't produce predictable numbers in a tunnel...that is why I am on it.
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Are you still toting the project around on your car or did you get a van?
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Are you still toting the project around on your car or did you get a van?
Still in my small Volvo.
There is an other limiting factor ( besides lack of funding ) I cannot rise any bigger wind turbine than this...the decent Reynolds number would require 2-3 times bigger turbine.
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There was still one weak link here...the aluminium extension of the legs.
I am working to end it ( flexing ). ;)
[attach=1]
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This seemed to stiffen the aluminium extension once and for all.
[attach=1]
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Ready to rock....6 carbon fibre covered 6,5 mm plywood strips will be added in the upper part to where the tower part bending force is the greatest on the legs.
[attach=1]
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I hope this ends the tower nodding when windy. ;D
[attach=1]
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How about taking video on next run?
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Taken a lot of videos...great way of analyzing stuff.
Yesterday I tested the 3rd prototype blades in the new set up in 7 m/s wind.
The efficiency was ½ of what the bigger blades had on half the wind speed.
Smaller blade/wing has 2 x lift coefficiency and drag....aspect ratio is 5 where as 4th has 8.
10-20 would be decent...even great.
What is funny is that 3rd set of blades rotated 2 x as fast in the same wind speed as the 4th set....without load.
There is something funny happening there I don't just get.
Anyone care to explain me ?
Tower was stiffer...but not tough enough to take 4th blades in to 10 m/s wind.
[attach=1]
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Ok...now I found the glitch here....anyone want to take a guess on it ? ???
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So more lift coefficiency or lower aspect ratio reduced efficiency?
My gut instinct would be on this style of VAWT that flat boards with zero angle of attack would work better than an aerodynamic shape simply due to the peak torque would come from the points nearest and furthest from wind origin. Lenz used drag scoops to draw power from the recovery phase between those two positions. But nearest those two positions are where the magic happens. Mind you, at perfect nearest and furthest points everything should be in balance (potential energy peak) so nothing actually happens until you approach or leave those points.
Lower aspect ratio in my thinking would mean less of your arc would be spent transitioning. I wouldn't doubt that the lower aspect ratio would create more torque at start up but then peak early as rpm's increase. A higher aspect ratio should give you more arc for the wing in transition. Lower torque would develop until the rpm's get closer to the drag limit, which would be higher rpm's due to lower drag at the aspect ratio.
I also thought they used the center wing to create a directional center point offset the center of rotation, so the center of rotation is slightly set outwards and perpidicular with the wind. The offset would not improve airflow, just use torque of aligning to the wind to improve startup as the downwind side would be further from support.
But if I understand you correctly, your results are in direct opposition to my gut instincts.
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So more lift coefficiency or lower aspect ratio reduced efficiency?
My gut instinct would be on this style of VAWT that flat boards with zero angle of attack would work better than an aerodynamic shape simply due to the peak torque would come from the points nearest and furthest from wind origin. Lenz used drag scoops to draw power from the recovery phase between those two positions. But nearest those two positions are where the magic happens. Mind you, at perfect nearest and furthest points everything should be in balance (potential energy peak) so nothing actually happens until you approach or leave those points.
Lower aspect ratio in my thinking would mean less of your arc would be spent transitioning. I wouldn't doubt that the lower aspect ratio would create more torque at start up but then peak early as rpm's increase. A higher aspect ratio should give you more arc for the wing in transition. Lower torque would develop until the rpm's get closer to the drag limit, which would be higher rpm's due to lower drag at the aspect ratio.
But if I understand you correctly, your results are in direct opposition to my gut instincts.
Yes....you have to remember I have an innovation in this which sorta makes a difference (at least I hope so).
I have to go to test fourth time soon...it is getting chilly here again.
I think I know now why the tower was shaking even though I have a less lift coefficient 4th set of blades.
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4 blades, 3 legs, setup oscillation in between supports...
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4 blades, 3 legs, setup oscillation in between supports...
Yes Mary...there has to be a support in between the legs...they bend ever so slightly.
I try once more to get a decent efficiency figure out this.
If not...then I have to wait for a situation with a decent funding to get right kinda axial flux generator....more space, workforce etc.
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your workmanship is good. you need too understand the 9 by 12 magnet and stator relationship. in that way you can "dial in" a specificity load in real time. And don't forget the potential to make the most electricity.
I spoke to Flux about another WAWT situation his reply, was just because its spinning does not mean its making power.
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4 blades, 3 legs, setup oscillation in between supports...
Yes Mary...there has to be a support in between the legs...they bend ever so slightly.
I try once more to get a decent efficiency figure out this.
If not...then I have to wait for a situation with a decent funding to get right kinda axial flux generator....more space, workforce etc.
I am well versed in 3 legged tower harmonics... I have had to help friends add weights to tower legs to damp violent tower harmonics that were literally shaking antennas apart.
This tower had lead weights mounted inside the legs(2" angle iron 1/4 inch thick!) to stop the top antenna from whipping 12" back and forth...
That tower is 3' wide on the face and was 80' tall for the main tower, rotating stub added 20 more feet.
(https://i.imgur.com/Nw6DB37.jpg)
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Yes Mary....damping is the word here...to find right kinda stiffnes that might even counter act the frequency the system is trying to tremble itself down. :)
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your workmanship is good. you need too understand the 9 by 12 magnet and stator relationship. in that way you can "dial in" a specificity load in real time. And don't forget the potential to make the most electricity.
I spoke to Flux about another WAWT situation his reply, was just because its spinning does not mean its making power.
I need to get more rpm out of the slicker prolifed wing...I am working on it.
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[attach=1]
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(Attachment Link)
This part is now also fiber glass reinforced.
[attach=1]
It is easy to test the better stiffness as Ihave the extra 4th leg left...as it was made to a tripod.
It looks like new after some paint.
[attach=2]
[attach=3]
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Stiffness was increased by 7x and 5x in other direction.
[attach=1]
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That aerodynamical part on top looks quite a bit larger than before.
How did the new torque arm turn out?
Aerodynamical part indeed is a big...that is why it tries to tears the tower down...in each test..... now the legs are 6 times stiffer.
[attach=1]
I did some serious balancing too and straightening here...I hope all goes well.
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How much offset is there from the center of rotation to your central wing? I assume some of the wobble you experience comes as your central wing aligns to the air direction. The larger the offset the more the wobble I suppose. Any noticeable offset should allow self starting.
Honestly, I assume this is a huge device I gather by its size relationship of the wing to the size of the Dewalt drill next to it. Has to be big enough for 3kW at least.
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How much offset is there from the center of rotation to your central wing? I assume some of the wobble you experience comes as your central wing aligns to the air direction. The larger the offset the more the wobble I suppose. Any noticeable offset should allow self starting.
Honestly, I assume this is a huge device I gather by its size relationship of the wing to the size of the Dewalt drill next to it. Has to be big enough for 3kW at least.
Yes you are quite right.
It was so strong in last tests that the system loosened those anchor bolts from the bottom part of the legs....and broke one halogenlight and loosened one ballbearing from
the housing in the torque arm.
The corrections I made enabled 40% more efficiency but still too low to make any difference...I presume I need to add more resistance...shorten the legs and put little more carbon fibre in the tower.
The chosen generator ( bike hub motor ) may be the biggest culprit in this for the poor performance.
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Perhaps you can go for a smaller test prototype version so you can study the results and eliminate the static being generated from the mobile version. As it is now its not a very practical test subject. What you have is a very refined version for the wings that I'd assume your final product should look. But honestly it is so large you really need a sturdy fixed tower for something with potential for that much potential power. I fear your prototype could hurt you.
Trust me, for s***s and giggles we made a 20+ foot wide rotor out of sheet metal and found it ran out of control and self destructed because it was more a pinwheel than an actual windmill. When the wind shifted and the sheet metal arms folded like spaghetti noodles, my heart literally stopped because we had no idea how that was going to end. Luckily the guy holding up the 20 foot plank that it was mounted on was nimble enough to avoid getting hit in the head. Smaller prototypes are safer.
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Perhaps you can go for a smaller test prototype version so you can study the results and eliminate the static being generated from the mobile version. As it is now its not a very practical test subject. What you have is a very refined version for the wings that I'd assume your final product should look. But honestly it is so large you really need a sturdy fixed tower for something with potential for that much potential power. I fear your prototype could hurt you.
Trust me, for s***s and giggles we made a 20+ foot wide rotor out of sheet metal and found it ran out of control and self destructed because it was more a pinwheel than an actual windmill. When the wind shifted and the sheet metal arms folded like spaghetti noodles, my heart literally stopped because we had no idea how that was going to end. Luckily the guy holding up the 20 foot plank that it was mounted on was nimble enough to avoid getting hit in the head. Smaller prototypes are safer.
Yes this has turned in to a real sport like the gladiators fought on the arena in Rome 2 000 years ago.
I have fixed all shortcomings I saw in the previous test now. Sadly the weather is not coping...but I just might be able to test it before the blizzard strikes.
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Taking it down in 15 m/s wind was like a decisive fight in opening of the Troy.
[attach=1]
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Wow. Glad you didn't get hurt. It has enough power at that speed to definitely remove limbs.
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Wow. Glad you didn't get hurt. It has enough power at that speed to definitely remove limbs.
Yes it rotates much slower than the previous smaller turbines. At 85-100 rpms in 6 m/s wind. Much too slow for the generator that is rated for 170 rpm.
Had the blades been 3-4 meters long and moment arm like 1100 mm it would have been just fine.
Now I have to figure how to make a 1 kw sized turbine generator for 50-80 rpm.
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I realized that I am getting more and more measurable current and power if I increase the load. So i increased the load even more.
Hopefully I can finally measure a decent out put. ;)
[attach=1]
[attach=2]
[attach=3]
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Pretty soon, ships at sea will avoid this shoreline, thinking there's a new lighthouse there!
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Yes in fact the ships really can see it.
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Like the Christmas movie where the guy wants his Christmas lights to be seen from space LOL
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Like the Christmas movie where the guy wants his Christmas lights to be seen from space LOL
Yes Mary....what I need is more speed to the rotation.
I have made 5 changes to the system. Making new blades again.
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Test post for topspeed
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Example message
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I cannot post pics.
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Sorry, the site is still broken.
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[bl[/b] b
I know
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Sorry gang, I just can't help my self. I just need to be able to speak.
Look. Every software change/development/progress will bring inherent risks with it like unforeseen bugs or even worse.
That is why my advice is to have a proper automated test procedure in place.
Now I am not suggesting the Test Driven Development methodology as I just never felt really pleasant with that as it requires a rather lot of design up front efforts. And by the time the User expectation and Technical Design is done then the users have already changed their minds.
So I have settled down on on an agile approach in where we are quick to iterate on basis of current goals of the users that can change all the time. However make sure that an iteration never forgets to take into account which of the automated tests need to be updated this iteration or which can hold on for another cycle.
I am always open to have a one on one with someone for advice. I mean that is the least I can do for all the great support I am getting here.
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Sorry gang, I just can't help my self. I just need to be able to speak.
Look. Every software change/development/progress will bring inherent risks with it like unforeseen bugs or even worse.
That is why my advice is to have a proper automated test procedure in place.
Now I am not suggesting the Test Driven Development methodology as I just never felt really pleasant with that as it requires a rather lot of design up front efforts. And by the time the User expectation and Technical Design is done then the users have already changed their minds.
So I have settled down on on an agile approach in where we are quick to iterate on basis of current goals of the users that can change all the time. However make sure that an iteration never forgets to take into account which of the automated tests need to be updated this iteration or which can hold on for another cycle.
I am always open to have a one on one with someone for advice. I mean that is the least I can do for all the great support I am getting here.
Is it a bug or a hacker here in work ?
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Sorry gang, I just can't help my self. I just need to be able to speak.
Look. Every software change/development/progress will bring inherent risks with it like unforeseen bugs or even worse.
That is why my advice is to have a proper automated test procedure in place.
Now I am not suggesting the Test Driven Development methodology as I just never felt really pleasant with that as it requires a rather lot of design up front efforts. And by the time the User expectation and Technical Design is done then the users have already changed their minds.
So I have settled down on on an agile approach in where we are quick to iterate on basis of current goals of the users that can change all the time. However make sure that an iteration never forgets to take into account which of the automated tests need to be updated this iteration or which can hold on for another cycle.
I am always open to have a one on one with someone for advice. I mean that is the least I can do for all the great support I am getting here.
Is it a bug or a hacker here in work ?
More of a hosting "issue" that either of the other two.
Hacker would've locked all of out completely with wanting $$$.
JW is working with TechAdmin on this issue. I can see what Mary B is posting easy enough.
Hope that helps
Bruce S
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Sorry gang, I just can't help my self. I just need to be able to speak.
Look. Every software change/development/progress will bring inherent risks with it like unforeseen bugs or even worse.
That is why my advice is to have a proper automated test procedure in place.
Now I am not suggesting the Test Driven Development methodology as I just never felt really pleasant with that as it requires a rather lot of design up front efforts. And by the time the User expectation and Technical Design is done then the users have already changed their minds.
So I have settled down on on an agile approach in where we are quick to iterate on basis of current goals of the users that can change all the time. However make sure that an iteration never forgets to take into account which of the automated tests need to be updated this iteration or which can hold on for another cycle.
I am always open to have a one on one with someone for advice. I mean that is the least I can do for all the great support I am getting here.
Is it a bug or a hacker here in work ?
More of a hosting "issue" that either of the other two.
Hacker would've locked all of out completely with wanting $$$.
JW is working with TechAdmin on this issue. I can see what Mary B is posting easy enough.
Hope that helps
Bruce S
I am using an external host for my pics instead of uploading them here.
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SMF is real weird about uploading images. Remotely hosted, and any images that have already been uploaded here previously will show no problem.
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;)
Ok dudes and babes !
I have nothing to show (but pictures in next post), but I can update.
In order to get some kinda positive results I have gotten really serious with this turbine developemnt of mine....like dead serious. :o
New tower is being done....with lot more heavy lumber 3''x 3'' and different kind...previous was a HAWT tower.
Moment arm is a bit shorter...but almost half as thick...and totally aerodynamic.
Wings are longer but more narrow. Foil is conventional.
This is all possible because of the new wood press and revitalization of the old heavy press. I have now wood composite available that is strong as steel ( percentage wise in weight ).
Load is higher....and wires thicker.
I need to get like 300-400 % better results to get where I wanted.
What do you think will I succeed...or fail again ? :)
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(https://scontent-arn2-1.xx.fbcdn.net/v/t39.30808-6/429985670_374932905434292_3861555122500705244_n.jpg?_nc_cat=109&ccb=1-7&_nc_sid=5f2048&_nc_ohc=xUKzbPNUtS4AX_4KiqR&_nc_ht=scontent-arn2-1.xx&oh=00_AfAWAARpyzVVgmfgdcF-ajUHTPdeDlIdOXoi39Km8loxxA&oe=65EDCE84)
Ok...image tool works out fine. This is the trailing edge part of the aerodynamic fairing of the moment arm. Half way...cover is missing and most of the filling.
(https://scontent-arn2-1.xx.fbcdn.net/v/t39.30808-6/428633534_371374012456848_1435519263069358956_n.jpg?_nc_cat=109&ccb=1-7&_nc_sid=5f2048&_nc_ohc=vJgBpGwvFdcAX8TF5Yh&_nc_oc=AQlcvemCfMsyRLIN8BP4oI10DrtLIzkyILq4zCivKPQiotp8TKzPlR2yghNlRUCkFr0&_nc_ht=scontent-arn2-1.xx&oh=00_AfB1KHp_480EHUwwGiwNpMQt07Y87tXRq_T5_QC6w3SNZg&oe=65EE0CDC)
Here we go:
(https://scontent-arn2-1.xx.fbcdn.net/v/t39.30808-6/429664152_374842162110033_8519506245213786044_n.jpg?stp=dst-jpg_p526x296&_nc_cat=109&ccb=1-7&_nc_sid=5f2048&_nc_ohc=aosxc_2HQd8AX9mg800&_nc_ht=scontent-arn2-1.xx&oh=00_AfBwl6FDFn7D3wP278lYQrRSLUgOGTdjWYLmbuykIzRioQ&oe=65ED1410)
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sweet topspeed.
I see that you and I have the same workbench :). But that is where our similarities stop I am afraid.
I can already tell you have far more craftsmanship and also some machines in the background I do not even recognize, let alone know how to operate them :)
cool stuff!!
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I have learned to use them...I sucked in wood works in school.
Driving force for me is the attempt to save the world...( for my daughter et al).
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so we have more similarities after all. I am also thinking about my offspring when I keep hammering on.
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so we have more similarities after all. I am also thinking about my offspring when I keep hammering on.
I also use possibly more Cola drinks than you...as I have studied in GA Tech.
(https://scontent-arn2-1.xx.fbcdn.net/v/t39.30808-6/430824609_380249124902670_1235419182391357009_n.jpg?_nc_cat=106&ccb=1-7&_nc_sid=5f2048&_nc_ohc=J9bZjNryLl8AX_4uoeR&_nc_ht=scontent-arn2-1.xx&oh=00_AfCXgr4739dGgFSkrC89i9WFgbizXae2mecE6hgMg7HEyg&oe=65F1244D)
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Are you both in Norway?
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hahha not me at least. I am printing pullies in the NL.
And unless topspeed is out and about he is probably in Finland :)
Damned cold here too with this chilling wind in the NL. And we are already heading into spring mind you.
But the potatoes have been promoted to a spot outside non the less. I do not hope it will freeze again this season.
But I have come to learn that me complaining about my local weather is a bad idea. There are people out there far worse off then I have ever experienced.
Some parts of the US can be brutal these days (or perhaps always have been) and Finland. Well Finland I think can be brutal as well. But I heard from someone who lives there that there is almost no wind there in winter time. At least in the part where he lives. That is a bummer :(
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hahahha Cola.
ahh Cola. Now I am not old enough to ever had the real !coca! cola. you know the one with the good stuff in it :)
Then they turned to caffeine which I only started consuming a few years ago in the form of coffee. in BULK though :)
Nah my drink of choice is a good spirit. One that gets one twirling instantly ;)
But yes sometimes I favor some cola.
---------
But then with a twist added :)
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;)
Ok dudes and babes !
I have nothing to show (but pictures in next post), but I can update.
In order to get some kinda positive results I have gotten really serious with this turbine developemnt of mine....like dead serious. :o
New tower is being done....with lot more heavy lumber 3''x 3'' and different kind...previous was a HAWT tower.
Moment arm is a bit shorter...but almost half as thick...and totally aerodynamic.
Wings are longer but more narrow. Foil is conventional.
This is all possible because of the new wood press and revitalization of the old heavy press. I have now wood composite available that is strong as steel ( percentage wise in weight ).
Load is higher....and wires thicker.
I need to get like 300-400 % better results to get where I wanted.
What do you think will I succeed...or fail again ? :)
I think you and I should collaborate!
I am not reading much outside my bubble as I have learned that leads me to posting on someone else's threads like I do now. And I have also learned that can blow up in my face so I am rather hesitant regarding that.
But I think you and I are in the same boat.
At least the same continent ;)
Would it be a stretch to use metric as a baseline?
I mean I am not trying to diss at the brothers and sisters on the correct side of the pond but I am hoping/guessing that they have a better understanding/feeling of metric than we do of imperial.
Is my assumption correct? And how would we know?
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Well I guess Finland's flag is closer to his origin flag lol
I take NL to be Newfoundland?
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Nah Brother,
The NL stands for The Netherlands. I take no pride being born in a culture that made possible a lot of things. Some of them good most of them less so.
I consider my self without a nationality.
I am a self proclaimed world citizen.
One other reason for me to hammer on about a VAWT is that one day there will be a spinning one on Bali, the paradise (in the travel brochures, the hard reality is that it is the least bad part of Indonesia if we want to use honest language), and all my contributors are invited to come and have a stay on my land there if I ever get to find a good spot.
{1}and a wind turbine makes little sense in those regions. I am not sure if it is about being at the equator but windy.com sure is not holding back on the fact that there is little wind to be had at all{/1}
{2}But even so, in Jakarta when on a roof top of my families home in a low rise urban setting I can feel enough wind that makes me want to put a VAWT there. So let us just see what happens if both topspeed's and my experiments come to fruition to make sure.{/2}
{3}I went overboard. Completely changing the topic. I am so sorry. It would be ok for mods to just delete my last post regarding my own efforts.. This topic is about topspeed's efforts{/3}
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Topspeed has a name that truly fits his build. Not only is he going for fast, he has regular high windspeeds to test with. And boy does his project live up to his moniker.
Like skid's waterwheel project, I can see topspeed's design becoming a commercial endeavor.
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@Topspeed,
If you come install it on Bali then I will be your first customer :)
But Indonesia is not know for consistent enforcement of the regulations so there might be hiccups at customs. Usually these hiccups are resolved by employing an ancient method. One that involved motivating the officer involved to play ball somehow.
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@Topspeed,
If you come install it on Bali then I will be your first customer :)
But Indonesia is not know for consistent enforcement of the regulations so there might be hiccups at customs. Usually these hiccups are resolved by employing an ancient method. One that involved motivating the officer involved to play ball somehow.
Ok I am a ball player. ;D
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hahahha Cola.
ahh Cola. Now I am not old enough to ever had the real !coca! cola. you know the one with the good stuff in it :)
Then they turned to caffeine which I only started consuming a few years ago in the form of coffee. in BULK though :)
Nah my drink of choice is a good spirit. One that gets one twirling instantly ;)
But yes sometimes I favor some cola.
---------
But then with a twist added :)
After the war people here used to pour amfetamine in their coffee...it was supposed to be envigorating.
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;)
Ok dudes and babes !
I have nothing to show (but pictures in next post), but I can update.
In order to get some kinda positive results I have gotten really serious with this turbine developemnt of mine....like dead serious. :o
New tower is being done....with lot more heavy lumber 3''x 3'' and different kind...previous was a HAWT tower.
Moment arm is a bit shorter...but almost half as thick...and totally aerodynamic.
Wings are longer but more narrow. Foil is conventional.
This is all possible because of the new wood press and revitalization of the old heavy press. I have now wood composite available that is strong as steel ( percentage wise in weight ).
Load is higher....and wires thicker.
I need to get like 300-400 % better results to get where I wanted.
What do you think will I succeed...or fail again ? :)
I think you and I should collaborate!
I am not reading much outside my bubble as I have learned that leads me to posting on someone else's threads like I do now. And I have also learned that can blow up in my face so I am rather hesitant regarding that.
But I think you and I are in the same boat.
At least the same continent ;)
Would it be a stretch to use metric as a baseline?
I mean I am not trying to diss at the brothers and sisters on the correct side of the pond but I am hoping/guessing that they have a better understanding/feeling of metric than we do of imperial.
Is my assumption correct? And how would we know?
Metric is just fine by me. :D
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Google has tools to change form one to the other...
25.4mm to the inch
2.54 cm per inch
from there it is easy to get feet...
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Google has tools to change form one to the other...
25.4mm to the inch
2.54 cm per inch
from there it is easy to get feet...
Yes.
I am open to all suggestios...as I was cut short here where I operate.
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My suggestion is to use metric as most of the people, even those on the correct side of the pond, have a feeling with that.
For those that do not then indeed there is always google :)
However I advice against google even though I always use their search :(
https://www.omnicalculator.com/conversion/imperial-to-metric-conversion
is what I would recommend if at all trustworthy.
I for one stopped trusting their calculator regarding the VAWT configuration of the wind turbine calculator.
https://www.omnicalculator.com/ecology/wind-turbine
Ok sure, I might just not fully understood how to dial in the numbers yet but to me this is too ambiguous.
Google has tools to change form one to the other...
25.4mm to the inch
2.54 cm per inch
from there it is easy to get feet...
Yes.
I am open to all suggestios...as I was cut short here where I operate.
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My suggestion is to use metric as most of the people, even those on the correct side of the pond, have a feeling with that.
For those that do not then indeed there is always google :)
However I advice against google even though I always use their search :(
https://www.omnicalculator.com/conversion/imperial-to-metric-conversion
is what I would recommend if at all trustworthy.
I for one stopped trusting their calculator regarding the VAWT configuration of the wind turbine calculator.
https://www.omnicalculator.com/ecology/wind-turbine
Ok sure, I might just not fully understood how to dial in the numbers yet but to me this is too ambiguous.
Google has tools to change form one to the other...
25.4mm to the inch
2.54 cm per inch
from there it is easy to get feet...
Yes.
I am open to all suggestios...as I was cut short here where I operate.
Thanks I liked the calculators.
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The Idaho Black Hawk tilt rotor clocked 38%
ANEW in Poland 41,5%
And Single Wing Energy oy 40%
So the efficiency is not at 30% for VAWTs.
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wow, please allow me to be soo ignorant/blunt and yet soo intrigued.
please get me up to speed? top speed even if you will :)
I would like to learn more af what it is you are talking about here.
{1}So are you somehow showing evidence of what my gut has been telling me that this omnicalulator is not entirely accurate?
My lord do I want to get to the bottom of this :){/1}
{2}when i search for The Idaho Black Hawk tilt rotor. I get cool yet non related stuff
same goes for ANEW in Poland :(
yes Single Wing Energy oy I can find. yet now I have to plow through. hmm I really do not want to do that yet.
I am here to help and learn not to start a new study :)
Can you please help me get going?
{/2}
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wow, please allow me to be soo ignorant/blunt and yet soo intrigued.
please get me up to speed? top speed even if you will :)
I would like to learn more af what it is you are talking about here.
{1}So are you somehow showing evidence of what my gut has been telling me that this omnicalulator is not entirely accurate?
My lord do I want to get to the bottom of this :){/1}
{2}when i search for The Idaho Black Hawk tilt rotor. I get cool yet non related stuff
same goes for ANEW in Poland :(
yes Single Wing Energy oy I can find. yet now I have to plow through. hmm I really do not want to do that yet.
I am here to help and learn not to start a new study :)
Can you please help me get going?
{/2}
I remember very well the 38% claim of the widely tested Black Hawk Tilt Rotor....from years back.
Chief of SWE told me they got 40% of their machine.
The ANEW is measured ( 70%) of the BETZ...so it is 41.5%(into the grid).
I also know another bankrupted firm telling 38% but only 36% when switched into campered foil.
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New tower assemled once:
(https://scontent-arn2-1.xx.fbcdn.net/v/t39.30808-6/438082874_411354588458790_544059892346502777_n.jpg?_nc_cat=107&ccb=1-7&_nc_sid=5f2048&_nc_ohc=EQw1Wq9sVKgQ7kNvgEWRYkz&_nc_ht=scontent-arn2-1.xx&oh=00_AfA8b-G2hOmKfLjD6oI0pJc4Ev9FFdGk17rclmkCuzcXzg&oe=66364FC2)
(https://scontent-arn2-1.xx.fbcdn.net/v/t39.30808-6/439999482_411357401791842_9199029307159909007_n.jpg?_nc_cat=100&ccb=1-7&_nc_sid=5f2048&_nc_ohc=h0RfgfJzzdYQ7kNvgEK3a5p&_nc_ht=scontent-arn2-1.xx&oh=00_AfDjz8bGeH2cCl4LBuX5jULsdbai1vlB4QwDc0jsEAsphA&oe=663654A4)
Surface of the new moment arm....now.
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I am really eager to keep following you topspeed.
On my end your post had only image place holders so I could not see the update :(
Probably because of my browser rightfully so being configured to be extra paranoid with leaking data.
For the admins this is one of the URL's that got blocked by my browser
https://scontent-arn2-1.xx.fbcdn.net/v/t39.30808-6/438082874_411354588458790_544059892346502777_n.jpg?_nc_cat=107&ccb=1-7&_nc_sid=5f2048&_nc_ohc=EQw1Wq9sVKgQ7kNvgEWRYkz&_nc_ht=scontent-arn2-1.xx&oh=00_AfA8b-G2hOmKfLjD6oI0pJc4Ev9FFdGk17rclmkCuzcXzg&oe=66364FC2
Btw Ulrich. I already found who to talk to to play ball with at the Bali customs agency :) hahaha
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That's a facebook link and they got temporary signatures to show up, since Meta don't want us to use 1mb of their bandwidth and can't afford servers the image signature is scrambled every so often so people can't hotlink images off there.
@topspeed please put the actual images and don't hotlink off facebook image links, as it will only work for a couple of hours and then break itself, sadly not something I can do anything about :( You can rest assured that if you upload the images on our forum they won't go away instead (unless the server and the backups implode but we don't talk about that ;D ).
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That's a facebook link and they got temporary signatures to show up, since Meta don't want us to use 1mb of their bandwidth and can't afford servers the image signature is scrambled every so often so people can't hotlink images off there.
@topspeed please put the actual images and don't hotlink off facebook image links, as it will only work for a couple of hours and then break itself, sadly not something I can do anything about :( You can rest assured that if you upload the images on our forum they won't go away instead (unless the server and the backups implode but we don't talk about that ;D ).
Do image system work now ?
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were working on it
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our host had been set at PHP 7 SMF now its at 8.4 or something. they said well be changed to php 7.4
we need to have new forum software. SMF has become too old...
JW
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Do image system work now ?
Yes, been a while :) https://www.fieldlines.com/index.php/topic,150905.0.html