UC知道Automobile Flywheel Energy
来源：百度知道 编辑：UC知道 时间：2024/05/26 04:19:55
Gasoline has an extraordinarily high energy density. If automobiles
used flywheels to store their energy, what mass and speed would
the flywheel need in order to have the same stored energy as the
gasoline in the gas tank?
used flywheels to store their energy, what mass and speed would
the flywheel need in order to have the same stored energy as the
gasoline in the gas tank?
For a normal sized car, the capacity of a fuel tank is 150gal, which is converted to 0.57 m3
the density of oil is about 0.8kg/m3
energy density of oil is about 45.7 MJ/kg
so, the total energy in a tank is
0.57*0.8*45.7M=20.8MJ
Now, for flywheels,we want a big and fast one to match the energy.
A standard regenerative braking flywheel for trains weighs 600kg, with a diameter 500mm, and rpm 8000
it produce 1/2Iw^2=33MJ, about the similar amount of the gas.