A compressible turbulence model for the pressure–strain correlation

Abstract

Recent DNS (Direct Numerical Simulation) results indicate that the main compressibility effect comes from the reduced pressure–strain term due to reduced pressure fluctuations. Using the concept of moving equilibrium in compressible homogeneous shear flow, we develop a new compressible pressure–strain model by modifying the incompressible linear pressure–strain model, which is characterized by a decrease in the primary redistribution term but an increase in the secondary redistribution term. The model was applied to a compressible mixing layer. The predicted results show that the growth rate is reduced with increasing convective Mach number and the Reynolds stresses are reduced. All the components of the pressure–strain term and the shear stress anisotropy are reduced with the increase of the compressibility, whereas the normal stress anisotropy is increased—then results are in accord with experimental and DNS results.

Keywords:

• Compressible turbulence
• Pressure–strain correlation
• Moving equilibrium
• Homogeneous shear flow
• Compressible mixing layer