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Logged in diaries / The moving of topics wouth auther consent
« Last post by brandnewb on February 26, 2024, 07:58:13 AM »especially in my case I would have respected some kind of heads up yes?
I have watched the video of Topspeed. It is a nice explanation of how such a windmill works. However, there is one substantial mistake. It is said that the vane is in parallel to the wind if the rotor turns out op the wind but this isn't correct. As the rotor has a certain eccentricity e and as the rotor has a certain thrust Ft, the rotor moment Mr = Ft * e. This rotor moment must be in balance with the vane moment Mv around the tower axis. The vane moment is the product of the force on the vane blade Fv and the vane radius rv at the aeodynamic centre of the vane blade. So Mv = Fv * rv. Fv is about linear to the angle of attack alfa in between the vane blade and the wind direction. You only get a certain Fv if the vane blade makes a certain angle alfa with the wind direction. So the vane blade is never in parallel to the wind direction for stationairy conditions. The angle alfa depends on the vane geometry and the wind speed. The higher the wind speed, the smaller the angle. The vane moment due to the aerodynamic force on the vane blade around the vane axis must also be in balance with the spring moment Ms around the vane axis.
This safety system is called the ecliptic safety system and more information about it is given in my public report KD 409. I have used a torsion spring around the vane axis because the spring moment of a torsion spring increases only a little for an increasing angle of rotation around the vane axis. The moment of a tension spring varies a lot because the distance of the heart of the spring and the heart of the vane axis is very dependent of the angle of rotation of the vane arm. I have chosen that the tower axis coincides with the vane axis because this simplifies the moment equations a lot.
I've been following your posts for sometime Branubie (if you spelled it like that it would be cool). you mentioned you would like to see a magnetic field. there's a way to do this its taught to all 6th graders in school.
Take your magnet set it on a wood table. put a piece of notebook paper over it (try to make it flat and level) then take some iron filings and sprinkle them on the paper. there you go, you will see the magnetic fieldlines.
JW
more than you asked for.Sure, every system that evolves long enough develops prehensile things like gall bladders and wisdom teeth.
I have not sat next to them at peak generation
For a long time I had an old Xantrex SW4024 inverter, which was a great workhorse inverter until mice built a nest in it, and it had to be scrapped. It worked well, but it was loud. Immediately after installing it in my "battery shed" and switching it on, I thought, "well that's never going in the house". Louder than a clothes dryer.
Fast-forward a couple of decades and I'm shopping for another inverter, which I would install in the house if it's quiet. But I can't find one. All this solid-state switching power supplies replacing coils of copper, but it's still just as noisy. If an inverter has any noise rating at all (some don't) it's pretty loud, like 60dB. That's actually quite loud, especially for a noise that is constantly humming away. The layout of my house puts the systems (electrical, heat, water etc.) in the center and the rooms radiate outward. That doesn't allow the inverter to be installed far away from bedrooms, the dining room, or the living room.
Outback doesn't give any noise data, but the installation manual for the Radian says this, "Avoid large air gaps behind the Radian inverter/charger and its mounting plate. These can result in louder mechanical noise during heavy inverting or charging." LOUDER?
Sunny Boy is 45 dB
SRNE is 60dB
Fronius is "<65dB"
These are all about as loud, or louder, than a clothes dryer. I can choose to close the door of my laundry room, but the electrical panel, where I would locate an inverter, is not isolated like that.
The Sunny Boy is the quietest I have found. Can anyone report their experience of the noise emitted by a SB inverter when it's inverting heavy loads?
Another solution is to use string inverters like Enphase, but that limits my options drastically.
Does anyone know of a quiet grid-tie inverter?
I still have a bunch of those.
I was given my first Mims book (the very one in your picture) when I was 14 years old. Learning to build little oscillators with 555's and other projects.
The 200-in-1 project kits came soon after.
Thanks for the memories, JW!
@MaryB,
I just got refunded my purchase of the F&P
Randy tells me that shipping is an additional 102 USD
I would have loved to play around with something like that. And indeed the stacking suggestion you made really is attractive to me.
Anyhow let's look forwards!
Also Ed, You know that I love you so that is why I have not send back the 16 magnets yet.
That's the second time that someone told me that they love me today. Cool, that's a good way to start my weekend.
Hz is cycles per second. 3.7 cycles, or magnets passes over the coils in 1 second equals 222 RPM.
Is that how fast you want the turbine to spin?
I am sure that you mean 3.7 RPM and not 3.7 Hz. Right?
Ed
Also Ed, You know that I love you so that is why I have not send back the 16 magnets yet.
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Here my obvious looking/.
For Me its ben posting videos
The system, login