Tangential Gas Injection Into a Supersonic Stream

Abstract

An experimental and numerical study of a tangential gas injection effect on a flow pattern and heat flux was carried out. The cooling gas (air) was injected in the flow (air) through the tangential axis-symmetric slot on the spherically blunted cylinder streamlined longitudinally. Experiments were conducted in TsAGI shock wind tunnel at free-stream Mach number M∞ = 6, Reynolds number Re∞, Rw = 0.76×106 (calculated for free-stream parameters and bluntness radius Rw = 37.5 mm), cylinder angle of attack α = 0…30°, slot width h* = hk/Rw = 0–0.021, free-stream stagnation temperature T0 = 710 K, pressure behind the normal shock ps = 0.5 bar. The mass rate of the injected gas G* = gj/πρ∞u∞rw2 = 0…0.12. It is shown, that maximum of the heat flux toward the sphere surface could be sufficiently decreased. For example, for coolant mass rate G* = 0.03 and angle of attack α = 0 the heat flux maximum is reduced by factor of two.