Numerical Study of Benchmark Experiments of Supersonic Compressor Cascades

Abstract

Benchmark cases of turbulent supersonic flow through compressor cascades were computed using a modern upwind scheme (Roe with MUSCL pre-processing), with the k-ω turbulence model, and the classical MacCormack method. The test cases derive from experiments through ARL SL 19 blade cascades at Detroit Diesel Allison (DDA) at the design Mach number, and at an off-design condition from ONERA. A verification of the codes was obtained by computing an inviscid flow through a wedge cascade at similar conditions. Predictions are in very good agreement for the DDA test case for the blade surface pressure distributions. Cleaner solutions were obtained using the Roe scheme. The MacCormack solution exhibits oscillations corresponding to oscillations of the shock-induced separating boundary layer on the pressure surface near the trailing edge. Wake flow Mach number distributions were very well predicted, but not flow angle distributions. Predictions are less accurate for the ONERA test case which was at a slightly higher Mach number and which moves shock locations sufficiently to cause a more sensitive response from the suction surface boundary layer.