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teddillard
10 September 2011, 1259
Alrighty then. remotecontact just posted a comment about threads about blowing stuff up, well, here's my plan. I really wanted my R5e build to get down to 200lbs, and since I'm running the Mars (Motoenergy) ME0709 I can cut 15lbs by using one of the original ETEK Briggs motors instead. It's got a huge reputation, runs at higher RPM than the Mars, is supposed to handle overvolting very well, but it's definitely going to be stressed. Besides all that, it's just about as classic in EV terms as the R5 is classic in roadracing terms.

http://www.eng.mu.edu/crovettj/ses/lib/motors/brigs/Etek_motor_pic.jpg

You know I love motor cooling. The first idea was to run a 12V fan on the thing combined with a ram scoop. Then I started talking to Jon at Catavolt. He suggested water mist cooling. Sick.

I found a few sites that sell water injection kits for cars http://www.coolingmist.com/ (I haven't seen that stuff since the '80s, thought it had gone the way of the Great Reptiles) and also found this KoolMist site: http://www.koolmist.com/

http://www.koolmist.com/images/heroshot.jpg

...seems to me, if you get the amount right, the water will pretty much vaporize and leave no residual liquid water. Plus, the image of the bike emitting a plume of steam was just too good.

I reckon the whole mess won't be much more than adding 5lbs to the thing... but if I could figure a way to have a gravity-fed venturi, maybe it could be a whole lot lighter...

The motor will be here on Monday. :D

podolefsky
10 September 2011, 1441
Cool idea. I guess you would need to refill the water reservoir pretty often, since the mist just evaporates. Any idea how much water it would use, say per mile?

teddillard
10 September 2011, 1641
Cool idea.

Oh g'wan wit yoo bad seff. :D

No, no idea how much, but certainly less than they use for the car injection system I reckon.

markcycle
10 September 2011, 1748
Keep the water off the brushes even as a mist it'll cause problems, wet carbon dust will short out any thing it touches. I think mist cooling is better suited for BLDC and other AC motors. I'm sealing the windings for Jon we're preparing for mist cooling but I don't know if we will do it of course its up to Jon.

teddillard
11 September 2011, 0310
... wet carbon dust ...

Ouch. There's my answer to "What could possibly go wrong?" :D Thanks Mark. (I didn't realize Jon was thinking about using it himself... hope I didn't spill any beans.)

... I haven't actually seen the motor yet, but the thinking was to combine the mist with a strong airflow and port the nozzles south of the brushes in the flow. Since the brushes are in the center of the radial motor and the force would spin it outward, that's what I was counting on to keep water off the brushes. ...in theory. :cool:

jazclrint
11 September 2011, 1953
Ely Schless uses a system that he built himself on his race bike. I tried to take pretty thorough video of it with Azhar's video camera. Don't know if the video will ever make the light of day. He had an electric pump, a reservoir that looked like an thin radiator reservoir and a module that he built that pulsed the electric motor I think every 4 seconds. He told me all the details, and it was very cool. If you could get a hold of him I am sure he would love to tell you all abut it. And it seemed to work wonders for his AC induction motor. Very nice guy. I think the hardest part will be making the module. But the pump he had might be a bit bulky looking for your liking on your build. It's not super big or anything, but I fear you might not like the esthetics. Don't know. Next time I'll be sure to bring my own video camera.

Also, for full disclosure, he had a separate cooling system for his controller that he made himself. But I won't clog up the thread talking about it too.