Abstract The cavity configurations produced by discontinuities at thermal protection system coated at surface of reentry space vehicles can lead to separation, attachment, and even transition of gas flows around the vehicle's surface, which can bring serious aerodynamic heating during the space vehicles reentering the Earth's atmosphere. In this paper, the continuum, slip, and transition flow regimes are chosen to represent reentry atmosphere environment and then a numerical investigation of hypersonic gas flows over a family of cavities is performed by using the direct simulation Monte Carlo method to reveal flow structures in the cavity flowfield under different length-to-depth ratios and freestream incoming Mach numbers. In particular, when the freestream varies from the continuum to the transition flow regimes, the minimal length-to-depth ratios required for cavity flow becoming the closed type are 8, 6, and 5, respectively. The effect of the freestream incoming Mach number on the cavity flow characteristics is getting weaker when the freestream varies from the continuum to the transition flow regime. The two significant findings are that the cavity flow characteristics under hypersonic conditions are primarily determined by cavity geometry rather than freestream incoming Mach number and secondly, effect of the freestream incoming Mach number on cavity flow type is very slight if the freestream is in the transition flow regime.
Highlights Cavity flow characteristics in three flow regimes are investigated by DSMC. The open, transitional, and closed cavity flow exist in all the three flow regimes. Cavity flow types mainly depend on cavity L/D ratio rather than freestream velocity. No shock wave appears in cavity flowfield if freestream in transition flow regime.
Flowfield structure characteristics of the hypersonic flow over a cavity: From the continuum to the transition flow regimes
Acta Astronautica ; 161 ; 87-100
2019-05-13
14 pages
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
A hypersonic flowfield around a reentry body including detailed base flow
British Library Conference Proceedings | 1995
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