COMPRESSIBILITY CORRECTIONS AND TWO-LAYER κ — ε MODELS FOR HYPERSONIC TURBULENT FLOWS ON UNSTRUCTURED GRID

SUMMARY To compute turbulent flows a two-layer κ — e model is used. The complete model and its shear-based reduction are analysed. Moreover different compressibility corrections are introduced in the compressible and in the shear-based versions of the model. Comparisons are made between the results obtained with and without these corrections. We obtain the best results with the shear-based version of the two-layer model with the Sarkar correction for the pressure/dilatation term combined with the Zeman correction for the dilatational dissipation and using a gradient closure model for the velocity/mean pressure gradient correlation. On the other hand, the compressible version overestimates the wall fluxes, even when using compressibility corrections.

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