Thermal Protection Characteristics of Annular Centripetal Film in Hypersonic Forward-Facing Cavity

The leading edge of hypersonic vehicles faces extreme thermal challenges, necessitating efficient thermal protection technologies to ensure the proper operation of the vehicles. Active thermal protection methods such as film cooling and transpiration cooling have been extensively researched, but studies on annular film cooling methods for forward-facing cavities remain relatively scarce. To address this, an annular centripetal film is designed for the hypersonic forward-facing cavity, and a comprehensive study is conducted in a long-duration hypersonic high-temperature wind tunnel. Experimental results indicate that the temperature rise in the cavity structure is not obvious when compared to the noncavity structure. The annular centripetal film in the hypersonic forward-facing cavity is capable of significantly reducing the temperature rise of the cavity’s bottom wall. When the mass flow rate of the annular centripetal film is [Formula: see text], the heating rate can be reduced by approximately 65% as compared to conditions without the annular centripetal film. Using the annular centripetal film can effectively reduce the heating rate of the cavity’s bottom wall as the total temperature of the inflow increases. Finally, through dimensional analysis, the fitted function curve is presented. These results can provide valuable references for the engineering design of thermal protection systems for hypersonic vehicles.