Flywheel Hybrid Cars

[R.I.D.E.]

LOL, had some springs custom made a while back. Maker told me $100 for one $200 for 100. Prototypes and one offs are ridiculously expensive. Ford once stated that it cost $600 in materials to build an SUV.

[trollbait]

Yet no one felt mass producing these flywheels for cars was worth it.

[R.I.D.E.]

Personally I like hydraulic accumulators. Flywheels are better for stationary storage, but pumped hydro beats them, using existing reservoirs.

[trollbait]

I am a little surprised that we hadn't seen hydraulic hybrids in production yet. Ford and UPS have done some test trucks, but I haven't heard of anything beyond that.

[R.I.D.E.]

Their weak point is running a bent axes pump (variable displacement) at prop shaft speed and they concluded they needed a "clean sheet of paper" design, which I developed based on ancient designs. Not actually a clean sheet of paper but never was configured as a drive system as originally developed.

Hydraulic drives have great efficiency up to about 1000 rpm at which point their efficiency drops of rather quickly.

[ChewChewTrain]

"Hydraulic accumulator"? Never heard of it. But if that's code for "girlfriend", I get it.

[R.I.D.E.]

Basically a balloon in a pressure vessel. Pressurize it to 2k psi, the pump fluid in it until it reaches 3-6000 psi (Americas cup racers are 12k psi). Pop had one in his B17 to lower the landing gear in the event of battle damage to the normal hydraulic pumps. They also had a manual crank in case of the failure of both primary and secondary systems.

http://www.innas.com/hydrid.html

[trollbait]

Originally Posted by ChewChewTrain

"Hydraulic accumulator"? Never heard of it. But if that's code for "girlfriend", I get it.

If you had a car younger than a decade, there is a chance the brake system could have one.

Hybrids use one in the friction brake system, because the ICE isn't on all the time to provide vacuum to power the brake booster. My Sonic also has one, and it is likely due to the same reasons with the small displacement and turbo.

A vacuum or hydraulic pump could do the same, and these brake systems have them, but the accumlator allows a smaller pump that only runs part of the time. It can also allows more powered braking events while EOCing.