Large eddy simulation of supersonic, compressible, turbulent mixing layers

摘要

Two and three dimensional large eddy simulations of a spatially developing supersonic mixing layer are performed using an in-house hybrid finite volume code that combines a fourth order non-dissipative MacCormack scheme for capturing turbulence and a second order SLAU2 upwind scheme for capturing shocks and other discontinuities in the flow. Three-dimensional predictions of growth rate and statistical moments in the self similar regime are consistent with past experimental and direct numerical simulation studies. The peak values of the transverse turbulence stresses are over predicted in two dimensional simulations. This may be attributed to the lack of vortex stretching and the lack of significant energy transfer to the smaller scales. This also leads to sustenance, pairing and overall growth of large coherent structures that result in an over-prediction of growth rate by about 20%. (C) 2019 Elsevier Masson SAS. All rights reserved.