Two-Stage High Pressure-Ratio Centrifugal Compressor

The report presents the aerodynamic design parameters along with the overall and stage test performances of a small, advanced, two-stage centrifugal compressor designed to attain high pressure ratios with fixed geometry. Complete performance test data was obtained at 60, 70, 80, 90, and 95 percent design speed, showing peak overall temperature rise adiabatic efficiencies of up to 80.5 percent, at pressure ratios between 3.4 and 11.2. Broad compressor flow ranges between surge and choke flows were exhibited, substantiating design predictions that operation at high pressure ratios could be obtained on a two- stage centrifugal compressor without the necessity for variable geometry.