8" Lenz Turbine stator pics

[wayne]

Hi

Well here is my 8" version. First used 5" dia and 6 coils of #32 wire of 200 turns. all single phase. Was impressed of the voltage output but low current. At about 10-15mph I could charge a 12v battery at 140ma. I put holes in airfoil to make light as possible. And used R/C cover in center nice pink shade. Worked not to bad.

Then made a wood 5" and cut out each little traingle and glued on wood plate. did a little router work. This time used 28 # wire and each phase had 47 turns or loops. Used the magnetic layout and wired it up as 3 phase. Was not to happy with results at a 10mph was only getting about 6 volts. Drove car to 40mph and got 13volts with short circuit test got .5amp. So about 6 watts for this unit. Was trying to follow Ed's stator maybe my dia is to small. But have a look. The turbine is on a zinc shaft with 5/16 bearings. Sorry no large pic will post later I forgot.

Wayne

[wayne]

[windstuffnow]

  Pretty cool Wayne !!!

    My little educational turbine has a stator of only 3.5 inches in diameter and 50 turns per coil.  I think the larger diameter spreads the magnets out to far for good flux through the coils.  Its not very powerful anyway because of the air core (single rotor).  To get the maximum from the unit the magnet should cover no less than 2 coil legs at any given time and its better if you can cover almost 3 coil legs.

    Below is a picture of how the legs are covered in my "3 single phase" windings...

You can see the magnet covers almost 3 slots, there are 2 coil legs per slot so each magnet fluxes 6 coil legs intermittently and there is always 4 coil legs under the magnets at any given time as it picks one up and drops one.  The little turbine doesn't do this because the magnets are small and rectangular in shape but it does cover more than one slot at any given time.

You could possibly place them in pairs to make up the difference such as 2 North as a pair and 2 south as a pair ( NN space SS space NN etc ).  Also if the coils are thick you may need to double the magnets to get the flux to reach through the coils.  Or simply build a small dual rotor unit, this will draw the flux through the coils.  A simple steel disc behind the coils will improve the output but if its stationary will create drag ( eddy currents ) and will require more wind but improves performance.  Small units you can get away with it.  Large units will convert it into a massive amount of heat.

    Keep up the good work!  Looks like your having fun!

Windstuff Ed

[wayne]

Hi Ed

Thanks for the help and I see what my problem is now. I always assumed you can only cover one leg at a time. I did try putting 12 1" magnetics on the plate and got no output at all. Which got me stumped. So either back to the drawing board or try putting them side by side. Live and learn and hope your new stator works out.

Many Thanks

Wayne

[RobD]

Hi Ed,

What did you say you got efficiency wise out of it? I'd like to try one.

RobD

[windstuffnow]

  Hi Wayne,

     I'm not sure if this will come out as I'm thinking it to give you a good mental picture...

You can't cover 2 legs of the same coil with the same pole, this cancels any power your getting.  You can, however, cover multiple coil legs with one pole as long as the other leg is either open or covered with another pole.  

I hope that came out well enough... my communication skills are a bit lacking when it comes to making pictures with words... Maybe someone else will chime in and focus the picture a bit...

Have Fun

Windstuff Ed

[windstuffnow]

  Rob,

   Are you talking about the educational turbine alternator or the Lenz turbine?

   The educational turbine alternator is quite poor as far as efficiency, its only a single rotor air core.

   If you mean the Lenz turbine I've seen anywhere from 37 to 42% measured from the shaft through a mini dyno.  I've only built small ones to date ( 2ft tall x 2ft dia ).  I don't know how they'll scale up.  It's on my project list this year to build and test a larger unit.  I plan to start with something around 4 to 6 ft tall and around 4ft in dia.  If it works out good then I'll build a larger one.  

   I haven't added it to my site as yet but the wings have been changed.  Still the same "J" configuration but I've added a different shape to the front of the J similar to the eipper 168 airfoil leading edge.  This reduces the drag from a Cd of almost 1 down to .5 while maintaining the open wing design which has a Cd of 2.3 on the downwind side.

Lots of fun this summer!!!

Windstuff Ed

[RobD]

The Lenz,

Those are impressive specs. I might put one down at Nancy's. Let me know when you get it worked out.

[hvirtane]

Hi,

here are some pictures about

how to make the stator

related to the magnets.

These pictures are for

a 6-magnet layout.

Three phase.

The magnets should

ideally be as wide

as the coil loops are

in one phase. But not bigger.

I think that it would be

a good idea to make laminates

for this kind of stator.

The laminates could be

as much thick sticking

outside the stator body

so that you can make

the grooves for the wires.

The grooves for the wires

in the laminates

you could make with

an angle grinder?

- Hannu

[hvirtane]

If you mean the Lenz turbine I've seen anywhere from 37 to 42% measured from the shaft through a mini dyno.  I've only built small ones to date ( 2ft tall x 2ft dia ).  I don't know how they'll scale up.  It's on my project list this year to build and test a larger unit.  I plan to start with something around 4 to 6 ft tall and around 4ft in dia.  If it works out good then I'll build a larger one.  

   I haven't added it to my site as yet but the wings have been changed.  Still the same "J" configuration but I've added a different shape to the front of the J similar to the eipper 168 airfoil leading edge.  This reduces the drag from a Cd of almost 1 down to .5 while maintaining the open wing design which has a Cd of 2.3 on the downwind side.

Lots of fun this summer!!!

This design looks to be really successful.

During the next week I'll start working again

with one of my friends to install

his big wind turbine.

I will start working in his place to install

there as well an experimental 'Lenz' turbine.

We have got lots of place there.

- Hannu

[aldon]

Good for you! I built my first alternator today, mostly to learn how. The information came from windstuffnow. It uses parts from my childhood (old wires, magnets) and scrap lumber. First stator I built did nothing, and I discovered it was because I spaced the wires to far apart in relation to the magnets. The second produces a whopping 1 volt when spun by hand. I used old ferrite magnets and left over magnet wire (about as thick as a hair) at thirty turns per coil. Used six magnets and nine coils. For my left over junk I think it's pretty impressive. Yours has had a lot more care though

aldon