Evolution of nonlinear processes in a hypersonic boundary layer on a sharp cone

Abstract

Nonlinear processes in a hypersonic boundary layer on a sharp cone are considered using the bicoherence method. The experiments are performed for a Mach number M ∞ = 5.95 with introduction of artificial wave packets at the frequency of the second mode. It is shown that the basic mechanism of nonlinear interaction at the location of the maximum r.m.s. voltage fluctuation is the subharmonic resonance; all nonlinear interactions in the maximum r.m.s. voltage fluctuation layer are related to the second mode of disturbances; nonlinear processes above and below that layer are much more intense than those in it. The effect of artificial disturbances on nonlinear interactions in the boundary layer is shown to be insignificant.