Direct numerical simulation of supersonic turbulent boundary layers

Morkovin’s hypothesis asserts that the effect of compressibility on turbulence statistics is negligible in boundary layers up to about Mach 5. As a consequence, density behaves almost as a passive scalar, or as a variable flow property, and other dynamic effects associated with density or pressure fluctuations are small [1]. Experimental results confirm this hypothesis, although a priori assumptions about compressibility effects are usually employed for the processing of experimental data [2].