DNS of Compressible Turbulent Flows

In the first part of this paper direct numerical simulation (DNS) is used to explore similarities and differences between fully developed supersonic turbulent plane channel and axisymmetric pipe flow bounded by isothermal walls. The comparison is based on equal friction Mach and Reynolds numbers. In the second part a comparison between supersonic turbulent nozzle and diffuser flow is undertaken based on DNS, with the aim to better understand the basic physics of these non-equilibrium flows which develop from upstream fully developed supersonic pipe flow. We focus on effects of mean extra rate of strain and mean dilatation on the axial Reynolds stress, the turbulence production and redistribution mechanisms.