遷音速遠心圧縮機内部流れの数値解析

―乱流モデルの影響―

抄録

In order to accurately predict an aerodynamic performance of test turbomachinery by a CFD code, it is required to properly select a turbulence model by considering its internal flow field. In this study, the flows in a centrifugal compressor under transonic condition were analyzed numerically by alternatively using the Spalart-Allmaras and the SST k-ω turbulence models. The computed results clarified the following differences. Compared with the Spalart-Allmaras model, the SST k-ω model overestimates the double-leakage tip clearance flow, which increases the loss generation significantly, and consequently underestimates the efficiency.