The sensitivity analysis of the design parameters of axisymmetric basic flowfield was performed using the software Isight

and the design parameters' effect on the overall performance was obtained

which shows that the leading edge compression angle and coefficient c affect most.The overall performance of the optimized basic flowfield was improved by optimization of three objectives of the polynomial response surface at design point.The hypersonic inward turning inlet with circular shape intake was designed based on the optimized basic flowfield.The numerical simulation results from when Mach number are 4~7 indicate that the inlet has relatively good mass capture ratio and compression efficiency

total pressure recovery coefficients are 0.581 and 0.513

and pressure ratios are 20.01 and 24.73 when Mach number are 6 and 7 respectively; the flow coefficient is 0.880 at the relay point of Mach number is 4

which verifies the feasibility of the optimization method.