Study on the effect of Mach number and initial amplitudes on the evolution of a single-mode shock-induced hydro-dynamic instability

Abstract

In the present study the Mach number and the high-initial amplitudes effects on the evolution of the single-mode shock wave induced instability were investigated. To distinguish between the above-mentioned effects, two sets of shock-tube experiments were conducted: high-initial amplitudes with a low-Mach incident shock; and small amplitude initial conditions with moderate-Mach incident shock. In the high-amplitude experiments a reduction of the initial velocity with respect to the linear prediction was measured. The results were compared to those predicted by a vorticity deposition model and to previous experiments with moderate and high Mach numbers done by others and good agreement was found. The result suggested that the high-initial amplitude effect is the dominant one rather then the high-Mach number effect as suggested by others. In the small amplitude-moderate Mach numbers experiments a reduction from the impulsive theory was noted at late stages.