稀薄流高超声速钝化前缘逆向射流流场特征研究

In order to accurately predict the interference flow characteristics between the opposing jet and the rarefied atmosphere in the rarefied transition region，the direct Monte Carlo algorithm（DSMC）is used to simulate the hypersonic flow under the interference of the opposing jet in the rarefied flow under the condition that the free flow Mach number is 7. The typical atmospheric environment of 60~90 km height is taken into account in the calculation，the effects of pressure ratio and Knudsen number of free flow on pressure，shear force and heat flux are studied. The results show that the opposing jet changes the structure of the flow field and has obvious heat protection performance，but the drag reduction effect is not obvious.The effect of opposing jet on hypersonic rarefied inflow increases with the increase of pressure ratio，and the size of the Mach disk also increases. With the increase of height，the rarefaction effect increases and the Knudsen number of free flow increases，so that the thickness of bow shock wave increases with the increase of height，and the reflux zone on the wall decreases and disappears. The results of this study provide physical insights into the mechanisms related to the interaction between opposing jets and hypersonic flows in rarefied flows.