2D steady wake predictions for airfoil cascades with beveled trailing edges

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The use of Reynolds-Averaged Navier-Stokes (RANS) codes to predict the statistics of turbulent flow fields is an important component of contemporary engineering design. Reliable predictions can be obtained once modeling constants are calibrated for particular flow types. In this work, we consider flow through airfoil cascades with beveled trailing edges, flows common in turbomachinery applications. They are characterized by separation along the trailing edge bevel which alters the effective camber of the airfoil and may destabilize to give time-dependent vortex shedding. As representative geometries, a 2D airfoil cascade and the Darpa-HIREP rotor at 76.2% span are considered, since experimental data for both are available. Time-asymptotic, 2D RANS solutions are computed using a two-equation q-w turbulence model with Jones-Launder-type and Wilcoxtype turbulence-model constants. Differences in the predicted separation bubble sizes are shown, and the nearwake flow solutions are compared to experimental data. Periodic flow solutions are discussed with attention directed toward stabilization of the flow using a short splitter plate. Our time-asymptotic RANS results could not isolate the better coefficients. Bolh sets predicted flows with reasonable agreement to experimental data in the near wake.