Effect of aspect ratio on 2-D hypersonic inlet performance

CFD simulations were performed on four 2-D hypersonic inlets with different aspect ratios in constant area.Effects of aspect ratio were analyzed at designed Mach 6 and other Mach numbers with different back pressures.The investigation suggest that with the reducing of length and wetted area while rising of aspect ratio,total pressure recovery coefficient of external compress ramp,mass flow ratio and coefficient of internal drag decrease;Inlet with low aspect ratio,as the huge area of three-dimensional-flow near the side wall,performance of inlet is affected notable and the starting ability become worse;When the inlets work in peak back pressure with design Mach number,the pressure that the 2-D hypersonic inlets can endure would reduce with the rising of aspect ratios.