Due to the flow separation induced by the severe curved shape of the inlet
a flow-control method based on the diversing flow grid was brought forward. Three different diversing flow grids were designed and a comparison of the supersonic inlet performance was conducted with a computational fluid dynamics method. Effects on the flow structure and working performance of the inlets with different diversing flow grids were attained. Results indicate that taking the grid as the flow control measure could avoid flow separation on the exit of the inlet by improving the flow structure and pressure distribution of the curved duct. It is proven that the performance of the inlet could be obviously improved by optimizing the diversing grid. Stability and total pressure recovery coefficient of the inlet with adoption of the airfoil shape grid could be raised by 10.3% and 9.8% at utmost while its interior resistance could be reduced by 5.3% at Mach number of 3.5.