Unsteadiness of Cowl Shock/Convex Corner Interaction in an Inlet

Abstract

Experiments in 2-D inlets for both sharp and round shoulders were conducted to study the influence of shoulder shapes and the relative position between the incident cowl shock and the shoulder on the unsteadiness of shock wave/turbulent boundary layer interaction (SWBLI) in a shock tunnel at Mach 5.9. For the sharp shoulder, as the incident shock moves upstream, the position of the separation shock foot changes little, and the fluctuating pressure concentrates approximately at the same location. For the round shoulder, the separation shock foot moves upstream and then crosses over the corner, and the peak positions of fluctuating pressure move upstream. The pre-multiplied spectra of fluctuating pressure near the separation shock increase in a wide bandwidth of low and middle frequency at the round shoulder, whereas the trend is not obvious at the low frequency for sharp shoulder. The present results support that the sharp shoulder has an ability to restrict the low-frequency unsteadiness of separation shock.