Analysis of slot injection beneath a thick hypersonic boundary layer

Abstract

A simplified analysis of tangential slot injection into a hypersonic (or supersonic) external flow having a thick. turbulent initial boundary layer including the effects of turbulent mixing, viscid/inviscid interaction, modest initial pressure mismatch. skin friction and heat transfer and heat release for reactive injectants is derived. The treatment uses hypersonic (or supersonic) small disturbance theory, a power law shape for the initial boundary layer velocity profile and a Crocco integral to get the temperature profile, a turbulent entrainment model including the effect of a Convective Mach Number, a quasi-1D assumption in the mixing and burning region, an instantaneous, onestep heat release model and simple models of skin friction and heat transfer. Good agreement o f predictions with experiment for several cases without and with burning for gross flowfield variables such as P(x), A(x), M(x), T o ( x ) , etc. was achieved The calculations need only about 1-2 seconds of CPU time on an Amdahl 5890 class computer. Lastly, calculations for combustor flowfields for a generic Scramjet vehicle at a flight Mach number of 10 with a realistic range of values for the boundary layer thickness at the injection station and slot height and injection Mach number and total temperature are given and discussed. v