gensem wrote:I ll make a draw (in mspaint, hehe) of what im probably going to the motor. I aim to run the cromotor with peaks close to 20k using a fan cooled 4110 24fet controller , so I cannot miss and make the hub ventilation half as good, it has to be very good.
edit: I was actually thinking of a way to create pressure in the intake side, so all the air flow in the gap (closed stator), but im not sure the air would have enough pressure. I was trying to find some sort of simulator but i was not able yet.
If the stator is closed then the other side of the stator doesn't get fresh air flow. With single side exhaust you're guaranteed some flow through the gap as long as you get the exhaust holes out at the same radius as the gap. At lesser radius the flow would surely be less and more complex in nature. Centrifugal force guarantees pressure. It's not big pressure, nor is it tremendous flow, but with the stator transferring heat to much cooler air it transfers much more heat.
The thing that drives me crazy about the all too common exhaust holes well away from the perimeter is how do they expect the hottest highest pressure air to flow out? I'm sure it mixes somewhat, but it's not a guaranteed inherent part of the gas circuit. You have a good handle on it, so I'm sure you'll get really good results, and it will reject heat drastically better than stock.
FWIW, hubmonster gets no warmer running at 30kw peak than it did at 16kw. If anything it's cooler, because the really high power flows for a shorter duration, and windings don't heat up instantly.
Something I haven't tried but my more recent research indicates could significantly increase flow is some type of air dam or cowling outside of the intake to both increase pressure in that region outside of the motor and to make it flow more freely into the intake holes. Without it we're trying to get air flowing by the holes turn to go in. I forget who brought that idea up in one of the threads but I researched it and it should increase flow pretty substantially. If I ever start having heat problems with a ventilated motor, I'll try that first, because making something to give it a try wouldn't even require taking the motor off, much less open it up. I bring it up in case you end up pushing your motor well into saturation, and need more cooling than I do, that there's still something quite easy to try.
I still think flow volume is just part of the equation, and what you do with the flow inside the motor is equally important.
I look forward to seeing what twists you add to the approach.