关键词: 超音速冲压喷气发动机;进气道;流量系数;风洞实验;数值仿真

Abstract: Based on a fixed geometry sidewall compression scramjet inlet,a varied geometry inlet with rotatable cowl was designed to increase the mass capture ratio.The cowl was designed as a triangle located at a forward place so that the mass flow spilling from the second spillage window can be entirely captured and the vortexes originated from the separated region on the sidewalls can spill out of the inlet from both sides of the cutback cowl.The performance of the varied geometry inlet was numerically studied at Mach number 6 and 4.Comparisons were made between the varied inlet and the fixed one.Numerical results indicate that most of the performance parameters of the varied inlet were obviously improved,among which higher mass capture ratio with 0.93 at Mach 6 and 0.71 at Mach 4 was obtained.Numerical and experimental investigation shows for high free-stream Mach number the triangle cowl of the varied inlet has an obvious effect on the flow improvement in the downstream isolator.

Key words: Supersonic combustion ramjet engine;Inlet;Flow coefficient;Wind tunnel test;Numerical simulation