Computational Investigation of an Oscillating Compressor Cascade Experiment

Kurzfassung

Computational fluid dynamics are applied to an oscillating compressor cascade experiment to gain further understanding of the flow field details and to assess the capability of the methods employed to model the relevant physics of the experiment. Previous unsteady two-dimensional Navier-Stokes calculations for this experiment have captured the global trends of the aeroelastic stability of the cascade, but have also highlighted severe problems in modelling the steady flow fields, resulting in considerable deviations of the calculated unsteady pressure magnitudes from the measured ones. In the present paper, the effects of three-dimensionability, viscosity, tip leakage, boundary conditions and leakage flows are studied. It is found that a small secondary inflow (approx. 1.5% ot the total massflow) has an overwhelming influence on the overall flowfield. Unsteady computations with and without this secondary inflow highlight the importance of using the correct steady base flow to achieve good unsteady results.