Instability of supersonic ramp flow with intermittent transition to turbulence

摘要

This paper investigates the global instability of supersonic ramp flow at Mach number 4.8 at different Reynolds numbers through direct numerical simulations. It is found that a critical Reynolds number exists for the flow to become globally unstable. Transition to turbulence happens downstream of the ramp with strong intermittency and is due to the breakdown of streaky structures fed by instability from the ramp separation region.