Rocket Turbines

Rocket turbines have come into prominence in the last 20 years chiefly as sources of power for rocket pumps and auxiliary missile requirements. Most are of an impulse type with low efficiencies yet very low weights. Varying from 2 to 20 in. in diam with powers from 1 to 15,000 hp, they are designed to operate for durations of 1 to 5 min with total life of 1 to 50 hr. Although rotational speeds are as high as 100,000 rpm, the tip Mach numbers are lower than in conventional turbojet blades.