          |
   |
|
Forums | Energy Efficiency | about flywheels....... |
| Author | Message |
dyoungkeit1 | Posted - 20 December 2002 10:47    Metal flywheels fly apart at extremely high speeds.With the formula: Energy = mass x velocity squared, increasing the mass isn't near as important as increasing the velocity because it's function is squared. With high quality steel failing @ 150ksi, a material failing @ 600ksi is a valid choice. That material is filament wound carbon fiber in an advanced aerospace composite, resin or metal matrix capable of up to 45,000 RPM. The high tech flywheel is even more high tech by being housed in a vacuum with magnetic non-friction bearings. The only contact with the outside world is via electricity. The motor/generator takes energy in by speeding up the velocity. Energy is removed by slowing the velocity. "Decay" is the power requred to maintain the magnetic bearings on earth. The half life is about 6 months for a 65 pound flywheel. The half life is much greater in space. The designed amperage of the motor/generator is a limiting factor. A low amp system in an auto would require an intermediate storage devise like a hydraulic accumulator for high torque passing & saving most of the braking energy. Braking accumulators would be various sized with pressure on the brake pedal determining how small the energy storage unit is valve directed. I don't believe a home unit would have to be buried for safety. I don't know of their commercial availability, but I do know of ways the composite performance can be improved. Dean Youngkeit 21 North 100 East Willard, Utah 84340 |