Effect of Centrifugal Force on Gas Flow in a Supersonic Turbine

To clarify the loss mechanism in supersonic turbines, the authors experimentally and numerically studied the flow condition between the rotor blades of a supersonic turbine for liquid rocket engines. The entrance Mach number was 1.94, and the turning angle of the blades was 120 deg. Shock waves were created at the leading edge of the blade. The Mach number and total pressure decreased in the passage between the blades, where the flow condition was restricted by the centrifugal force. Such degradation, which has also been reported in past studies, is an inherent feature of high-speed, large-turning-angle blades. Here, it was found that a convergent-divergent configuration of the passage between the blades suppressed the performance degradation of the supersonic turbine.