Numerical simulation of shock mach effect on normal shock/homogeneous turbulence interaction

摘要

Shock wave interactions with grid-generated homogeneous and isotropic turbulence are observed numerically by solving the time-dependent three-dimensional Navier-Stokes equations with k-ε turbulence model for a compressible fluid. Numerical measurements are taken before and after the interaction of turbulent regime with normal shock wave reflected from the end wall. All turbulent fluctuations are measured during the compression by reflected shock on turbulent field and it is observed that the longitudinal turbulent velocity fluctuations are amplified after the shock/turbulence interaction. The amplification of turbulent fluctuations and turbulent kinetic energy level depend on shock strength and shock induced flow conditions behind the shock wave. The amplification factor of longitudinal turbulence intensity is 1.985-2.120 and the amplification factor of turbulent kinetic energy level is 3.086-3.410 in interaction of normal shock with homogeneous, isotropic turbulence for incident shock Mach number 1.50 and the amplification magnitude of longitudinal turbulence intensity and turbulent kinetic energy level decrease for incident shock Mach number 2.20 where the dissipation rate of turbulent kinetic energy decrease in all the cases of shock/turbulence interaction.