Numerical simulation of high-speed planar mixing layer

In this paper gas-kinetic BGK scheme is applied to simulate 2-D supersonic mixing layer with free-stream Mach numbers ranging from 1.1 to 1.9 on one side and 2.3 to 3.1 on the other. The convective Mach number M_c falls in the range 0.2–1.0. The numerical results provide the flow-field structure, the characteristic of velocity fluctuation, the self-similarity profiles of the mean velocity, Reynolds stresses and high-order moments of velocity fluctuation. The mean velocity field and the normalized growth rate agree well with experimental results. Due to 2-D limitations the velocity fluctuation intensities and shear stress are overpredicted, especially in cases with high M_c. The pairings of large structures in high M_c mixing layers still exist, although compressibility restrains their development. Present study reveals the good property of the BGK scheme in the simulation of compressible flows that ensures its wide applications.