Numerical Studies of Heat Transfer on Hypersonic Blunt Bodies with Gas Injection

Numerical analysis of hypersonic continuum and rarefied gas flows near blunt probes is presented under conditions of intensive gas blowing from the surface. Nonequilibrium parameters in the multicomponent flows were evaluated for slot and uniform injections of air, helium, and hydrogen. Numerical results indicate that the most effective cooling of the probe surface occurs at moderate uniform injections and moderate Reynolds numbers. It has been found that at transitional flow conditions, when the mass air injection rate equals 0.7 of the free-stream mass flux, the viscous layer is blown completely off the surface, and the heat transfer is zero.