Hughs 4ft truck wind test.

[Jerry]

I've sold my old S-10 that I used for wind test.

So I set up my Ford ranger all electric truck for this test.

I mounted an anamometer on the hood just in front of the drivers wiper. The MPH readings on the truck speedometer were faster the the mph #s on the anamometer by 5 to 10 mph.

I'm sure the wind up at the blades was even faster yet?

I used 2 diferant loads. 1 load was two 6 volt golf cart batteries wired for 12 volts.

The other was a 2KW 1 ohm resistor.

Here is the wind generator with my blades atop the mast in the bed of the truck.

Strange thing about the resistor load. The blades seem to be in bad stall  up to about 15 mph. There was very low power till then once above 15 mph they broke loos and power went way up way fast.

I'll do all the # crunching and report back.

                         Jerry

[Jerry]

OK I'm sure this posting will stir up some dust. And the Sh%&*%$ will hit the fan.

Hugh Piggot wood blades.

I'll show the test #s for the battery load first.

  10  mph   12.89 watts

  15  mph   37.15 watts

  20  mph   49.91 watts

  25  mph   88.73 watts

  30  mph  102.98 watts

Now the test #s for the 1 ohm resistor load

  15  mph    4.6  watts

  20  mph   12.6  watts

  25  mph    134  watts

  30  mph    224  watts

Now the foam pipe blades.

 Battery load wind test.

 10  mph   38.1  watts

 15  mph    104  watts

 20  mph    204  watts

 25  mph   323.4 watts

 30  mph   499.8 watts

Now the 1 ohm resistor load.

 15  mph    20   watts

 20  mph   460   watts

 25  mph   644   watts

 30  mph   750   watts

Now for the "Jerry Blade" battery load wind test.

 10  mph    51   watts

 15  mph    64   watts

 20  mph  119.25 watts

 25  mph   355   watts

 30  mph   562.5 watts

Now the "Jerry Blade" resistor load wind test.

 15  mph    5.6  watts

 20  mph    525  watts       that was 21 amps at 25 volts

 25  mph    780  watts       that was 26 amps at 30 volts

 30  mph   1050  watts       that was 30 amps at 35 volts

Keep in mind in the resistor test the voltage was alowed to klime as high as the resistor and the alt would could produce. Not so with the battery load. The battery load caped or clamped the voltage to 15 volts.

It was very dificult for the blades to break loose at low wind speeds with the resistor load but once the did the power came on fast.

In the battery load the alt was free wheeling until the alt hit 12.7 volts the the battery began to load the alt and blades.

OK guys I've got my armor on let the flack begin.

I was alone in the truck for the battery tests. My good freind Mark came over for the resistor test a did shot gun and test recording duties for me.

The "Jerry Blades" are in the first truck picture.

                           Jerry

 

[Jerry]

The nose cone or nestle was just setting there for looks. I did not have it on the blade during tests.

After looking at the test #s I see why the "Jerry Blades" Are a good match for my Garbogen. The Garbogens cut in is about 100 rpm higher then the rotor alt.

This allows my blade to ramp up some rpm befor loading. Even I'm surprized about the good MPH range on the foam pipe blades.

They definetly worked very well in the normal wind speed range. The 10 to 15 mph range.

The stator got slightly warm but nothing eccesive. This unit is Jerry rigged so heat was not an isue allthough the air temp was in the 80s during this test.

I was happy to see 1 KW without any stator heat damage.

I'll definetly be building the 8 ft diameter pipe blades for my NEO 14-11.

That will definetly slow down my e-truck.

                           Jerry

[Flux]

Well done Jerry this is all good stuff.

Any chance that you could repeat the test with Hugh's blades with a 2 ohm load resistor?

I suspect you have more twist on the tip of your blades than intended, you look to have done something strange marking out the trailing edge but even so I doubt that it is far off the mark.

It is normal with a resistor for the start up to be poor, ideally you need a different resistor value for each wind speed.

Ideally you need to run at a set speed and adjust the resistor for maximum output for each blade. That is the only way to be sure you are matched.

Certainly you have proved that your blades are a better match for those test conditions.

I would guess that the prop wind speed is above the speedometer figure by quite a bit. Sadly the anemometer reading mounted there is useless so ignore it. Take the spedo figures and they are fine for comparison.

Flux

[oztules]

Well tested Jerry, your energy is a joy to behold.

I did a quick calculation re wind speeds.... not to complain, just to get a feel for it.

Using your best match blade @20mph, we got 525 watts. For a 1.2m prop, @20mph we could reasonably expect 150 or so watts before we hit the alternator losses. We got 525 including the alt losses. This would place your 20mph at probably nearer 32- 33mph (31mph with a CP of .3 = 570W) allowing for alt losses probably about 32mph as a reference?? This is a fair result, and shows pretty fair matching of the prop to the alt to the wind.

The wooden blade managed only 12.6watts for the same comparable speed. I will have to assume the prop saw actually approx 32mph wind, as per the Jerry blade all things being equal.

The actual power available to be harvested by the blades of either style at this speed is about (CP=1) 2000watts....

Now it comes a surprise that 12W is all you could manage to harvest with that alt and those blades.

I think this shows that you are either a terrible blade carver, or these blades are absolutely not suited to that alternator with that load.... I'm suspecting the latter

This is what I mean by wondering what we are actually testing. Unless they are matched, it is difficult to understand what has been shown.... other than the blades that you have evolved, suit that setup very well, and the blades you carved do not.

But I find it difficult to believe that Hugh would expound a device that had that much difficulty harvesting 12W from 2000watts available.(.6% conversion) The alt didn't burn up, so it was not lost there.... obviously for some reason, we didn't get a proper handle on the wind.

I note that Flux seems to feel that it is time to find out what it is matched to... and I would be interested in that outcome as well.... If that doesn't get very marked improvements, then ..... I am not inclined to get you to make my wooden blades for me.

My chainsawn ones seem to do a bit better than that.... closer to CP=.3+ ...... 5kw into a resistive load around 32 mph.... and nothing like that into a 48v battery bank.. only about 2kw@57v, and only about 100watts into a 24v bank (28v...) get the picture .... same blades, same alt different load same winds.) As you can see if I had tested it as a 24v unit.... it was a dud. as a 48v unit it was great, as a resistive drive unit into 2 ohms.... a killer

The figuring for your above tests may not be perfect, and the blades were obviously in stall, but... thats matching the load.....even with a battery match (50W) (which is slightly better here for getting a bit further out of stall) it is still only 2% extraction... not exactly a super duper match??

Well done all the same Jerry

..........oztules

[gizmo]

Very interesting stuff, and some good results.

I agree with Flux, that anemometer is in a bad place. The wind speed over a bonnet varies a lot, depending how far away from the nose your taking the measurements, and if the flow has seperated from the bonnet skin or not. At the back of the bonnet, and bottom of the windscreen, is a high pressure point. Thats why the air vents are there, the air is forced into them.

I would trust the car speedo, so long as your not driving into a head wind. Or mount the anemometor on a stick a couple of feet above the bull bar.

Glenn

[electrondady1]

hello jerry .

 your tests are impressive

i am mostly interested in the resistance tests for heating purposes

 if you put some big capacitors in line with your resistors i wonder what the results would be.

[Beaufort]

Nice results; I've been following your testing and it's great to see some objective comparisons.  Assuming your new foam pipe blades are much lighter than the wood H. Piggot blades, did you notice how quickly they came up to speed compared to the wood ones?  Are there any thoughts to how a lower rotational inertia would affect real-world performance on a tower?  

I seem to recall the overall opinion here is that it's better to have more mass spinning to free-wheel when there are gaps in the wind.  However there is a much higher gyroscopic force with heavier blades that scrubs power when turning, and lighter blades will come up to flying speed in lighter winds much sooner.  I haven't run across any theoretical studies to show this, but I'd bet there are some opinions here from experience.  I'm guessing that heavier blades are better for "ideal" wind locations with high averages, and lighter blades are better for turbulent non-ideal places with lower speeds?

Beaufort

[Flux]

To use capacitors the load has to be on the ac side, not what is being tried here. The snag with very low load resistors is that the capacitors have to be big. They have to be non polarised so even if you use electrolytics they have to be twice as big and you have to handle a ripple current that would probably mean using parallel banks.

For this voltage and power level electronic matching with a series regulator would be far cheaper and simpler. Is there enough heat available on normal days to even consider using a 4ft machine for heating? I draw the line at 12ft.

Flux

[Jerry]

Hi all.

I suspect the problem with the wood blades is my wood carving ability.

The were made in haist. Althogh I atemped to follow the book and they looked the part I'm still not sure they were close enough.

This is why I asked the question and hoped Hugh would take a look at the blade pictures.

I know it would be hard to tell but he is the master blade builder and they are his design.

Well at this point it dose not matter. On the return trip there was a big bang.

My Hugh blades are no more. I had used a thin  pice of plexy for the front round and it broke just above the 30 mph mark.

The bang was vey loud the truck shook vialently, nearly went in the dicth.

If someone has a good set built to Hughs specs I would be more then happy to test them and then return them.

I do know for my preferance I'll be building more pipe blade for the disc rotor type machines.

Even with the 100% perfect wood carved blade I'm not sure they'll be better, but hey thats just my opinion.

It was fun and intresting. One thing for sure there was over 1 KW comming out of the littel alt on a warm day for a short time and it survived just fine. Even the big bang did not hurt it. Scared the $%^T out of me though.

Thanks for all the input guys.

                    Jerry

[Jerry]

Hi Beaufort.

Yes the wood blades were (RIPices) but I don't think enough to effect the flywheel aspect much.

I think its the big scoop at the root, The steep root angle and the quick  but smooth transition to flat  towards the tip.

I think the wood blade presents more of a flat surface to the wind and the scoop of the foam pipe blade just extracks more root power.

I'm not sure of the angles on the wood blade. The "Jerry Blades" are 23 degrees at the root and 2 degrees at the tip.

I don't know how you could or what you would call the angle of the foam pipe blades at the root scoop. I just know it looks very steep.

I'm thinking this is where all the startup touqure comes from.

I think more of the flywheel effect is coming from the very heavy disc and magnet weight.

I just looked up the published official wind tunnel test maid by the university tunnel for Hughs 4ft diameter wind generator.

  5 mph 0   watts

 10 mph 20  watts

 15 mph 50  watts

 20 mph 140 watts

 25 mph 230 watts

 30 mph 350 watts

 I belive these #s to be very acurate and with a proper blade.

                            Jerry

[Flux]

Jerry I am glad you found these figures. I think I may have them on my old computer but it would be difficult to get at them now.

I would expect the wind speeds to be very accurate ( better than you will get in real wind). There may be some boundary effects but the machine is probably small enough for it not to be serious.

The lower wind figures compare well with my tests but I didn't have enough wind to go high enough . My graph goes to 20mph but the figures in that region will be very limited and mainly gusts so the figures will be skewed against the high end output.

I seem to remember the MIT test was done with a car battery with no means of holding the volts. The results will be accurate for those conditions but will be higher than if the battery clamped the volts as it normally would at about 14v.

I suspect these are the most accurate figures available for that machine. The curves also show the furling scheme working and just as with my machines there is a drop in power when furling kicks in.

Flux

[Jerry]

Hi Flux.

I just talked to my cabinet guy. He is building me a set (by the book) of the 4ft diameter Hugh Piggot carved wood blades. He said about one week.

I'm thinking about building another complete Hugh Piggot 4 ft diameter wind generator.

I have a small out building that sets broad side to the prevailing winds.

The building  is 24 ft long. I'll mount the twin gennys. One at each end of the roof. I'll place an anamometer at the same hight between the 2 gennys.

I'll have them charge the same battery bank but each alt will have its own amp meter.

I'll place the wind speed meter between the amp meters. I'll have the Hugh Piggot 4ft diameter wood carved blades on 1 alt and the pipe blades on the other.

At any given wind speed I'll Take a picture of all 3 meters and post the pictures.

This will show real worl diferances between the blades. To make sure one side is not better than the other I'll swap blades per side for the next week.

This will take some time but I hope this will be the final answer to witch blade works best?

When I receive the blades from the cabinet builder I will post pictures for board aproval or disaproval?

I'll also be compairing star to Jerry rigged and the "Jerry Blades" as well.

Like I said this will take some time. I'm in the prosses of replacing the roof of my house. This willtake prority. Have to beet the rainy season you know.

I'll be reciving a set of TLG boast buster blades for compairison to the Hornet blades in a week or so. I'll flying them on a Hornet alt.

This will be both stock star and with my modes for both blade sets.

AH too many blades too many alts too many tests. I don't think I'll have my new 14-11 NEO done till next spring? I still want to fly my 14-11 ceramic on the e-truck to see how it stacks up to Hughs 8" single rotor at high wind speeds?

                             Jerry

[SparWeb]

How about putting the anemometer all alone on top of the stand to calibrate it?  You could drive around with a friend watching the anemo while you maintain at a constant speed, then relate the numbers later so that you can make the correction.  Try driving into the wind, then against the wind and taking the average, even if it is a calm day.  Does the Ranger have cruise?

Probably doesn't matter for comparitive numbers you want, but then OZ comes along and starts working out the aerodynamics...  I would have, too if he hadn't beat me to it!

Wait a sec, that's your electric Ranger, isn't it?  You could tell the neighbours that you've invented a machine to charge its batteries while you drive.

Infinite range is yours!

Admin!  Kurt!  Tom!  Delete this post for claims of over-unity!  

[Jerry]

Thats my most aked question when the see the wind genny in the bed and I tell them the truck is electric.

                           Jerry

[KilroyOdin]

Hi, super job and nice numbers. What kind of RPM's are you getting and is over spin a concern?

[Jerry]

Hi Kilroy.

Not sure about rpm. I could check my bench test #s. On the bench I recorded amps, volts, watts and rpm.

No I'm not concerned about over spin.

Thanks for the kind words.

                   Jerry