On the instability of inviscid, compressible free shear layers

The linear spatial instability of inviscid compressible laminar mixing of two parallel streams, comprised of the same gas, has been investigated with respect to two-dimensional wave disturbances. The effects of the velocity ratio, temperature ratio, and the temperature profile across the shear layer have been examined. A nearly universal dependence of the normalized maximum amplification rate on the convective Mach number is found, with the normalized maximum amplification rate decreasing significantly with increasing convective Mach number in the subsonic region. These results are in accord with those of recent growth rate experiments in compressible turbulent free shear layers and other similar recent calculations.