Thread: Parasitic loss
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Old 06-24-2003, 11:45 AM
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Quote:
Originally posted by scottj


Gears don't just lose power based on RPM and independent of force.

The rate at which power is lost in friction is proportional to the product of the tangentially transmitted force and the velocity of tooth engagement. If EITHER the force (HP) or the velocity (RPM)increases, the product, which is proportional to frictional losses, also increases. I think.
Scott
So do you think the best approximation for one particular car, would be to do the electric spin up test at the same accell rate that the car's motor is able to accel the car in that particular gear? Your RPM/time in fourth gear in the quarter mile, used as the baseline accel rate for the electric motor's spin-up test with the tranny in fourth gear.
I think the losses would increase, the quicker you attempt to spin-up the drivetrain. But probubly not too greatly. Just theorizing here.
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