Temporal Linear Stability Analysis of Three- Dimensional Compressible Binary Shear Layers

Temporal linear stability analysis is performed on the three-dimensional compressible binary shear layer for density ratios ranging from 1 to 32 and convective Mach numbers up to 2. Comparison is made with the results of spatial theory. Some stability properties are shared by both approaches, for example, the independence of the direction of propagation of the most unstable modes from the freestream density ratio, but other features are different: a single secondary mode appears instead of two at high compressibility. An empirical model is proposed for the wave length and phase speed of the most amplified waves. Direct numerical simulations show good agreement with linear inviscid theory for initial Reynolds numbers greater than 400. [PUBLICATION ABSTRACT]