Numerical simulation of a supersonic turbulent compressible jet in a co-flow with stochastic spectral inflow boundary conditions

Abstract

A compressible supersonic turbulent jet of a perfect gas in a co-flow with the formulation of stochastic spectral inflow boundary conditions is numerically modeled. The base equations are the LES averaged Navier – Stokes equations closed by the Smagorinsky model, the solution of which is carried out by the ENO scheme of the third order of accuracy. The stochastic boundary conditions at the inlet are constructed on the basis of the spectral method of generating fluctuations of gas-dynamic variables to obtain an inhomogeneous anisotropic turbulent flow. The numerical results of turbulent characteristics are compared with experimental data for the shear layer problem. The thickness of the shear layer is obtained, in which the growth of the shear layer between the jet and the co-flow for three types of grid (coarse, medium and fine) is demonstrated. Coherent vortex structures appearing in the jet are constructed in dynamics, which made it possible to analyze in detail the growth and development of vortices over time.