Modification Number Nine

[WXYZCIENCE]

While waiting for wire to arrive for the Ray3, I decided to give the RACA2 a run for it's money. By reducing the air gap I have increased the output by 20 %. I set up the alternator at 600 rpm with a 11 amp load. The open circuit voltage was 22 volts and loaded it dropped to 10 volts output, 110 watts. Ambient room temperature was 70 degrees. I placed a test thermometer between two of the coils in contact with the coils. I ran the alternator in this position for one hour. The temperature rise was 115 degrees F. I continued to run the test for another half hour and the temperature leveled out at 130 degrees F. At this point I decided to add a cooling fan to the design. The fan is cut from .01 inch aluminum and it is pictured here attached to the rotor.






Sixteen blades with 3/16" flutes. Next I added vent holes to one of the stator end plates.






The air will be ducted through the coils by an additional cowling. The coils were very easy to remove and the rotor can be serviced. Because the coils were 3/4" longer than the unit, there was plenty of room to add the fan. I will give the RACA2 another test and see if this modification keeps the temperature below 115 degrees F.


Joseph.

[windstuffnow]

  Gettin' pretty fancy there Joseph !  Looks nice.  

.

[stephent]

Was the final temp a rise above ambient? Or end temp of the coils?

Nice lookin work by the way.

[electrondady1]

realy nice workmanship , will the cowling be made of iron?

[vawtman]

Nice work Joe.Ive got a simular plan for cooling the axial im building.

 The cool thing about your radial ideas is that one can build them with wide diameters awesome for vawts i would think.

 I just have to stick with the current plan and not think so much.Ive probably had 50 modifications since i started coming down with this illness a couple years ago.

 Whats your plan for a turbine?

 Best of luck in your adventures

    V.....

[WXYZCIENCE]

Stephent, I read the post again and I did say temperature rise but the coils end temperature was what I was actually reporting.
Joseph.

[WXYZCIENCE]

The fan worked very well, with the same test the temperature leveled off at 115 degrees F. This test simulated a very heavy work load for this alternator.


I then paralleled two sets of eight coils and retested the output, into the same load at 900 rpm. The total resistance was quartered, the output 150 watts and the temperature was just over 90 degrees. More research required.
Joseph.

[WXYZCIENCE]

Electrondady, I tried a steel cover and increased the output by 5%. There was a hum and increased cogging so I will probably use a plastic or non-magnetic stainless steel for the cowling.
Joseph

[stephent]

A coil temp of 115F. isn't pushing the wire at all. That would be a cool "normal" temp for a running loaded motor.

But in the center of the coil it will be a bit higher and out in the sunlight on a hot day with 30/40 def F. higher ambient, you will have the same temp rise above ambient plus a bit more. Looks like your "torture" test is close to what I would expect out of it when outside and running/genning as a max for it.

Without more cooling anyway.

Stick it inside a box (if possible) and let ambient air temp rise to 90F/100F or so and check coil temps.

[coldspot]

wxyz-

I really like "your radial ideas"!!!!!

I've been following them along and admire your nice work!

An idea I've been saving for my own windmills-

I'll share now for all the great people on this forum !!!!!!!!!

The rotors from vacuume cleaners!

The part that makes the air move-

I've been saving them for a while now and they could be used in most mills from what I've seen.

Anyway, I thought I was on to something and now think that it should be shared with all to just be of some help.



l8r

[WXYZCIENCE]

Coldspot, I was going to use a vacuum cleaner blade but I can't reproduce them. This one was cut on my xwz machine. Thanks for the input.
Joseph.

[Bruce S]

Hello Joseph;

 Been following these and with great interest.

I have a few questions that perhaps with all the board searching and googling I may have passed them up.

Have you tried having the coils on the inside and the Magnets spinning around them around the outside of the coils but still inside of a cylinder?

I have been gathering up the need "stuff " to try one of these.

I am going about this is a "let's see what we can build with what we have" mentality.

Here's what I've come up with.

several hundred feet of 20 ga wire. hundreds of CDs and institutional size metal cans.

The wire I will work with and by using a little math magic decide the number of turns and length to come up with the closest setup including the air gap.

I have decided to use the metal cans as the backing due to the fact that I can get these all day long from my wife's work.

The magnets I have are ceramic 2"x1"x1/2" , I'm using these for the simple reason is that I have ~300 of these.

The 20 ga wire, I scored from pulling broken electric weed wackers from the trash and unwinding the wire carefully. the wire is in near perfect shape and all there for the taking. I even have the neighbors dropping off their old ones in my yard with a note to have fun:--)

They know that anything I do is safe and will give back to those who help me out.

Also, instead of having a simple wing or air foil type I plan on getting around the City's  rules by having the pole no more than 40' high with the "S" type wings up at the top with the gen set at the bottom.

Thoughts?

Would love to try out with NEOS but don't have any left and this is a junkyard trial, just for the see what we can do with what we have.

Bruce S

 

[RP]

Bruce,  If I understand you intend to place the magnets on the inside of a metal can for your rotor.  I'm not sure of the strength of ceramic magnets but I'd guess the metal cans will leak a lot of flux on the outside surface.

Consider adding some extra metal around the outside of the can to increase the total thickness of oron for the flux path.  A few things that come to mind would be several layers of metal strapping or iron wire.

[Bruce S]

RP;

  Thanks for the info will do just that. It was a concern, just wasn't all too sure about the leakage having the ceramics on the inside versus the way these RACA's have settled into.

Getting iron to build up the flux path is easy. metal strapping from shipping crates are all over around here.

Cheers;

Bruce S