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 cdruGo ColtsPremium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7 | reply to ttiiggy
Re: Does it matter which way an automotive rear end turns? said by ttiiggy:Wondered about having the driveshaft turn a BIG fan blade or something that would load the drive train to act as braking.
You would never move enough air that method to provide any significant braking power, at least in a timely manner to be useful. Conceivable you could use that power to spin up a massive flywheel to store the energy until the fan's resistance provided enough braking over time. But that's not practical, not to mention what happens when you need to brake and the flywheel is already spinning at capacity.
If you don't want to use friction braking, and compression braking isn't desired, then resistance or regenerative braking could be a possibility. The latter is how hybrid cars work. Instead of braking using friction, power is transmitted back to the electrical motor turned into a generator. The wheels spin the generator, producing electricity to recharge batteries that can be used to power the vehicle when it needs to accelerate instead of consuming fuel. On a much larger scale, locomotives do the same thing but instead of recharging batteries, the electricity is used to power banks of resistive strips (think electric furnaces). The heat is then discharged out the top of the locomotive by large fans. | |
 ttiiggyPremium
join:2001-03-27
Bozeman, MT | said by cdru:said by ttiiggy:Wondered about having the driveshaft turn a BIG fan blade or something that would load the drive train to act as braking.
You would never move enough air that method to provide any significant braking power I'm not thinking the AIR movement by itself would act as braking.
I don't really care if it is BLOWING any air.
Mostly, I just want the drag of turning the fan.
said by cdru:flywheel is already spinning at capacity.
I don't think I want to mess with a flywheel with the extra weight and bearings and balance and vibrations.
said by cdru:If you don't want to use friction braking, and compression braking isn't desired, then resistance or regenerative braking could be a possibility. The latter is how hybrid cars work. Instead of braking using friction, power is transmitted back to the electrical motor turned into a generator. The wheels spin the generator, producing electricity to recharge batteries that can be used to power the vehicle when it needs to accelerate instead of consuming fuel. On a much larger scale, locomotives do the same thing but instead of recharging batteries, the electricity is used to power banks of resistive strips (think electric furnaces). The heat is then discharged out the top of the locomotive by large fans.
I did think about turning a generator but didn't know what to do with the energy if batteries didn't need charged.
I'm not excited about generating extra heat with resistive strips.
That is where I thought turning the fan blades in the air might create drag to slow the vehicle. | |
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