Shock-Loss Model for Transonic and Supersonic Axial Compressors with Curved Blades

Abstract

Reliable efŽ ciency calculation of high-subsonic and transonic compressor stages requires a detailed and accurate prediction of the  owŽ eld within these stages. Despite the tremendous progress in turbomachinery computational  uid mechanics, the compressor designer still uses different loss correlations to estimate the total pressure losses and thus the efŽ ciency of the compressor stage. A new shock-loss model is presented for transonic and supersonic axial compressors with circular arc blade proŽ les. The model calculates the shock position, Mach number, expansion angle, and the shock total pressure losses. The model is integrated into a loss calculation procedure, where the shock, proŽ le, secondary, and total losses are calculated. To validate the model and to establish new loss correlations, available experimental data for several transonic compressor rotors were used. Detailed loss calculation results show that the blade tip region with high Mach numbers cause shock losses that are approximately one-third of the total pressure losses. In addition, correlations are presented for total pressure-loss coefŽ cient, proŽ le-loss coefŽ cient, and secondary  ow-loss coefŽ cients. These correlations allow the compressor designer to accurately estimate the blade losses and, therefore, the stage efŽ ciency.