Some results on the growth of instabilities in a shear layer

The linear spatial stability of a mixing layer between two parallel streams is considered, and a comparison is made between the stability of flows with and without a stationary splitter plate separating them upstream. The assumed velocity profile satisfies the condition of no slip on the splitter plate, but in other respects the flow is treated as inviscid. Account is taken of the jet spreading downstream, and expressions are obtained for the total amplification of an infinitesimal disturbance of a particular frequency as it travels downstream. The stability of a hot air jet is compared to that of a cold air jet with the same velocity profile.