Flow separation and reattachment of turbulent flows have practical implications in many devices like diffusers, combustors, airfoils. Flow over a backward-facing step (BFS) is a configuration that is often studied to understand the physical behavior of separated flows. Combustors and afterburners in ramjet and scramjet engines are designed to use BFS flows. Supersonic turbulent BFS flow provides flame-holding in scramjets. Supersonic BFS flow is analyzed computationally, focusing on turbulence models, turbulence parameters, wall temperature and heat flux, and predictions are compared with published experimental work. The Reynolds-stress turbulence model gives better predictions for reattachment length and for near-step flow, compared to other turbulence models. The SST k-co model is accurate in the shear layer region. Reattachment length varies inversely with inlet turbulence intensity. Increasing isothermal wall temperature increases the normalized reattachment length while inlet Mach number affects the reattachment length inversely, in contrast with previous findings for subsonic flow.
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