Stability of a laminar premixed supersonic free shear layer with chemical reactions

We discuss the stability of a 2-dimensional compressible supersonic flow in the wake of a flat plate. The fluid is a multi-species mixture which is undergoing finite rate chemical reactions. We consider the spatial stability of an infinitesimal disturbance in the fluid. Numerical solutions of the eigenvalue stability equations for both reactive and non-reactive supersonic flows are presented and discussed. The chemical reactions have significant influence on the stability behavior. For instance, a neutral eigenvalue is observed near the freestream Mach Number M_∞ ～- 2.375 for non-reactive case, but disappears when the reaction is turned on. For reactive flows, the eigenvalues are not very dependant on the free stream Mach number. The disturbance amplification rate is higher and the wave speed, c_r is lower for most of the reactive cases when compared with the non-reactive cases.