Instability of nonuniform density free shear layers with a wake profile

Abstract

The linear spatial instability characteristics of both uniform and nonuniform density plane mixing layers were investigated taking into account the wake component of the initial velocity profile. Two unstable modes were found. In the shear layer mode, the growth of the unstable disturbance leads to the usual Kelvin-Helmholtz rollup pattern, whereas in the wake mode, rollup patterns resemble those in wake flows