Wind tunnel test.

[Jerry]

I was able to do a few wind tests today. First My grand daughter and I tested her small science fair dual rotor. This Is the alt with 2 stators. One stator (delta jerry riged) is wound with 200 turns #24 gage and the other stator is wound with 116 turns of #21 gage (star with extra helper turns).

I also tested the 6 pole 3 coil, 3 phase motor conversion test alt.

I used a 2.5 hp tredmill motor with a 24" air mover blade to provide the wind. The tremill motor gets its DC power from a fullwave bridge of 4 25 amp top hat stud type diodes mounted on a heat sink. To smooth the DC  a 3,000UF/350 volt electrolytic cap is used.

AC is supplied to this doide package from a 4,000 watt, 120 volt variac. The variac provides 0 to 140 VAC.

I'm useing an Oregon Scientific amamometer for wind speed measurement. Voltage and amperage are tracked by a Fluke true rms meter plus 2 small HF meters for voltage and amperage readings.

Heres the anamometer.

Here are the meters and the small batteries used for the small dual rotor disc alt.

Here is the variac and an AC clamp on amp meter to track amps going in.

Here is the diode group and cap.

Heres another shot of the variac, meters and the anamometer transmiter.

Heres were all the wind comes from, tredmill motor and blade.

I tried several blades on the small disc alt. This blade from a 20" box fan was the only one fast enough for any measureable output. You also see the amamometers wind cups sensore generater thingy.

This is looking the other direction.

Heres a glimps of the covered area. Its sorta walled in on the sides as well as a roof. Its a fairly closed in area accept for the wind entrance and exit.

Now time to test the 6 pole, 3 coil, 3 phase ac motor conversion. This is the back side. I'm using 49" 3 blade, Jerry blade on this one.

This is from the front side.

Heres the complete setup.

Here are the doide groups for either star or delta/jerry riged conection.

Here is the large 2 volt cell I used on the 6 pole 3 phase alt. It measures 5"X6"X15" and its real heavy. During all the testing this battery went from cold 2.05 volts to 2.15 volts. Its a big load for these small amp readings so it was a vary stable test load.

Test #s on the small disc alt. I could only get a good reading at a littel over 20 mph on this one. Things were starting to shake abit.

Star at 23.3 mph .29 watts. Delta/jerry riged at 23.3 mph .71 watts.

Test #s on the 3 phase, 3 coil, motor conversion.

The anamometer gives an MPH reading every 60 seconds so it was a littel hard to track mph #s so I took a reading over a 3 minute period each.

Star 15-16.8 mph, .4944 watts. Delta/JR 15-15.9 mph, 2.03 watts.

Star 17.9-20.6 mph, 3.1 watts. Delta/JR 17.4-18.3 mph, 3.36 watts.

Star 23.3-24.2 mph, 9.576 watts. Delta/JR 19.7-23.7 mph 10.0405 watts.

It is aperant that stars low wind speed preformance falls behind but catches up in the top end high wind speeds.

However I have not wound the star cheater coil yet. After I do I'd expect 2 phase  styles to be real close at very high wind speeds. Its nice however to get better power in more normal or avewrage wind speeds.

It is also aperant that the higher power delta is needing a larger blade at the very high wind speed since it apears to make more power, it naturley would need a larger blade.

It was nice to see how it acts at 15 mph though. I don't think the cheater coils would brought star up to delta/JR at the 15 mph mark. It would have helped a littel but not much.

It will be intresting to build a full size 9 coil, 12 magnet alt and run the same test. I'm now thinking along those lines. That for sure will take some time. Most likley worth looking into though.

Well more tests to be done.

                               JK TAS Jerry

[nothing to lose]

Looks good.

Is that how you will test out that other motor, large 6 pole with the 8 arcs in it?

I like those pics, last 2 did not load for me though. Crappy dialup connection here seems to just give up on pictures sometimes. I'll try it again.

I am following your testing with great interest in this. Thanks for all the great posts and info in this and many other areas.

[Jerry]

Hi NTL.

Normaly I wind test with my S-10 truck. However on the last alt I tested that way some board members were concerned of inacurate readings from the wind excellerating over the truck cab and the influence of prevailing winds.

I thought this impromptoo wind tunnel with the anamometer just ahead of the wind genny would resolve this concern.

The time intervales between readings is troublesome but both star and delta are subject to the same conditions.

An anamometer with instant real time reading would help. I've thoughts of the home built wind gage with an analog meter for an instant reading. Also making vidio tape of the meters during testing. This could make better way to track #s and get more acurate measurements.

Some will sugjest a computer and data logging. Thats another art form for me to learn and as it is I don't get along with computers.

My time is allready streched beyond limmits. Puter logging would be nice though.

I've wanted for a long time to build an inclosed wind tunnel with 4 of the 24" air mover blades and 2 of my 100 LB 2 HP DC motors. This tunnel was to be 12ft long with turbulance defuser tubes in the center and doors on the exit to act as a flaiered opening for blades up to the 8 ft. range mounted a short distance from the exit.

Truck wind testing has allways been a pain. The tunnel could make things much easyer and hopefully more accruate?

Its aperant I need to build a full 9-12 dual rotor alt for this compairison.

The trick will be to wind the 2 in hand coils plus add the extra turns for star to help it for its lower voltage potential.

The 2 inhand part is easy, just adding the extra star turns to help star may be a trick.

I may just do the 2 seperat stator thing I've done with the small dual rotor test alt.

I'm thinking of an 8" dual rotor again. The last 8" I built worked so well so I think it would be a good size for this evaluation.

As per the 8 magnet motor conversion. To see its real power capability I'll do a truck wind test with that one. It will be 3 phase, 8 magnets, 6 coils. Since its 6 poles any 2 coils directly accross from each other can be either wire in peralell or in sires because they are in phase.

So there are 2 coils per phase. This offers quite a number of coil and phase grouping combinations.

This will be an intresting project.

                      JK TAS Jerry

[nothing to lose]

Just a quick post I thought of when you said "Normaly I wind test with my S-10 truck"

Would that be a Wind Genny powered Electric Truck then

 I geuss you mean the electric S-10.

[SparWeb]

Holy smokes, man.

That's some serious power dissipation equip you got there.  I'd put a lid on a capacitor that big (I must admit judging proportions in the photo are misleading - relative to your soccer ball, it's tiny.)

You could log your data with a video camera, then transcribe later.

[drdongle]

Jerry have you ever done a 8 magnet, 6 pole (3phase) conversion before and if so was that a good combination out put wize and what about cogging?

[Jerry]

Hi NTL.

No my electric truck is a 1985 Ford Ranger. I think Ed is converting an S-10?

My S-10 is my wind test truck.

OBTW your blades should go out tommorow. There all boxed up and ready for the UPS truck. We have daily PU at the store.

Tighten the 3 root mounting screws real tight. Then put the star locking nut on the back and cut the excess of with a Dremil heavt duty cut off wheel.

                          JK TAS Jerry

[Jerry]

Hi Steven.

The socer ball is one of those 3ft diameter soft type. The grand kids have a great time lonching over and knocking each other around with it.

I may try the video camera next test. If I was good with computers I could load the video here. Trouble is I ain"t good with computers?LOL

                     JK TAS Jerry

[Jerry]

Hi Dr. D.

No I've never used 8 magnets in a 6 pole. There may be a problem with a magnet centered on one pole and the magnets to its flanks may be partialy over that same pole.

I did do 8 Lowes ceramic magnets in an 8 pole single phase. That unit had very low output for 2 reasons. 1 the magnets were ceramic and the other was they were flat.

Areched or curve magnets have much better flux transfer to an arched or curve surface then do flat.

The cogging in this 6 pole I've just tested is very small. The old #29 magnets I'm using cover the entier face of the pole. I have done 6 #29s in this 6 pole alt but you need a pipe wrench to turn it. The #29s are to wide in a group of 8 to fit most motors I've found for conversion.

Nothing To loose has a curved NEO the will fit. I've purchased a set from him and I'm eager to do some 8 maget motor conversion testing. His magnets seem stronger then the old #29.

Most of my conversion have been 4 pole, 4 magnet, single phase, I have done a few 4 pole 3 phase and a few 6 pole single phase.

The posabilties on this 6 pole seem intreeging. Its the first ac motor I've rewound and it was very easy. If I must stay with 4 magnets in the 6 pole do to voltage lose because of magnet overlap it can still be wound 3 phase. This littel 6 pole 6 slot motor may become a very nice entry level project not requiering much exspence or effert.

Just gota try a few magnet and coils combinations for the best results. Nice thing about these motors there plentyfull and free. Just check the HAVAC shops old motor recycle bin or dumpster.

                              JK TAS Jerry

[nothing to lose]

Gee I thought I was gonna be able to make some jokes on the test trucks use of a wind gennie to power it's electric motor later. Yes I remember now you converted a Ford Ranger.

 I'll watch for the blades around Friday or next week then. I'll be glad to get some Jerry blades flying.

[drdongle]

With the 4 magnet conversions you have been doing I presume that you have been doing them NN SS NN SS or are they N S N S ?

I've seen a lot of blower motors but none like that six pole unit you have. what manufacturer made it?

[amiklic1]

How do you call those yellow, red and blue plastic "caps" used for connections (shown on the picture with diodes)? In Croatia there is no such thing to buy, so I'll oder that from USA. But don't know what to ask for. I had some of those in my GMC Van before, but I sold the van....

[ghurd]

"wire nut"

G-

[kenputer]

We call them marrette's

[hiker]

hey jerry--

have a small 1/3hp blower motor --somthing like yours 6 seperate poles-but with light wire..cut the rotor for 8 hd mags..had all the leads from the six coils coming out the back of motor..anyway it didn"t realy work that well with 8 mags..knocked off four of the mags and tried again..some what better.

i think with these type of motors they don"t work to well as 3 phase alts-like you said some coils see two mags on them at any one time..i do have a six pole rotor i may try..

it would most likly work the best..i should see well over 20 volts for each coil-at a low speed-so each coil will have its own rect. then all wired in parelle-for more amps.

later..............................