Large-Eddy Simulation of a Spatially Evolving Supersonic Turbulent Boundary-Layer Flow

Several issues involving the large-eddy simulation of wall-bounded compressible turbulent flows are investigated. A spatially evolving supersonic boundary layer is simulated using a high-order-accurate finite difference scheme and the dynamic subgrid-scale model. A parametric study suggests that the finite difference scheme has a detrimental effect on the resolution of the smaller scales due to excessive numerical dissipation from the spatial differencing. Also, because the dynamic model uses the smaller resolved-scale eddies to determine the model coefficients, the predicted coefficients do not have the appropriate values. The use of higher-order schemes is found to better capture the smaller resolved scales and to improve substantially the quality of the results. The effect of descretization errors on large-eddy simulation needs to be addressed further before proceeding with large-eddy simulation of flows of engineering interest