Monday, May 23, 2011

Parts for the Build










A 20 mm threded rod as a shaft.




















2 Bearings for the axial support.





















2 neodymium magnets, withe the poles opposing each other,forsupporting the vertical load.
50 * 25 *5 mm 20 kg pull force / magnet



















Fiat brakedisc for the magnets























12 neodymium magnets 25 mm* 19 mm 25 kg pull force.

Thursday, May 19, 2011











This how the assembly will look when the stator and magnet disc are mounetd.










The bering and hub.

An 20mm shaft supported verically by 2 flange beraings,and with 2 neodymium magnets supporting the horisantal weight,thus unloading the flange bearings and minimizing the force needed to rotate the turbine.

The stator











The stator will be a 9 coil 3 phase stator, in star confuration.
The coils will have 75 turns of 1,5 or 1,8 mm magnet wire












The entire stator will be casted in epoxy resin and mounted on bolts allowing it to be adjusted in height so that the clearence between the stator and the magnets is as little as possible.

The magnet plate












I have decided to use a brakedisc from a Fiat as base for my magnets, It is well balanced solid metal, and should be a good base for the magnets.
The magnets are 25 mm in dia and 15 mm high, The theoretical holdingforce is 22 kg per magnet
I have designed the plate so that I can add a second plate easilly making it a dual fulx alternator.
The magnets will be glued in place with epoxyresin.

Wednesday, May 18, 2011

Calulating the wind power.

I have been doing some math regarding the power of the wind.
The formula i found is
Power output = 0,5 * swept area * air density * v^3
where 0,5 is th betz value = the difference between the power of the wind and what can be generated as electricity.
Air desity= 1,23 since i live close to the sea.
Wind velocity m/s
and swept area 1.44 ( i have decided to make it 1200mm in diameter since that gives alot more drag-force .

Tuesday, May 17, 2011

Rough draft of the design.






























Basic design:
Diameter: 1200 mm
Height: 1200 mm


Blade width: 130 mm



Magneticly levitated with 2 neodymium magnets, and 2 flange-bearings supporting the shaft below the magnets.


Stator: 9 coils 75 turns 1.5 mm magnetwire

Magnets 12 1,5 " neodymium magnets grade N42.

Mounted on a 281mm brakedisc.












Project start

This i s a small blog about my project to build a veritcal axis wind tubine.

It will be built fron scratch, in my garage, hopfully it will be done by the end of 2011.