Design specifications require a shaft with a flywheel to rot

Design specifications require a shaft with a flywheel to rotate at 600 RPM and not fall below 580 RPM when loaded. When the load is engaged, the shaft supplies it a torque of 500 N m for 1/6 of a rotation. How large must the inertia of the flywheel be? If the flywheel is to be made of ASTM 20 cast iron (S_y = 98 MPa) and have an outer diameter of 750 nun and an inner diameter of 600 nun, what must its thickness be? How much does it weigh? Judging by its factor of safety, is it in any danger of yielding?

Solution

From the above given data inertia can be claculated in th folowing way

inertia = 688 m^4

Thickness = 56mm