Effects of Chemistry in Nonequilibrium Hypersonic Flow Around Blunt Bodies

摘要

In this paper, the influence of a chemical kineticmodel in hypersonic flow past blunt bodies is examined. Slow andnfast chemical kineticmodels are investigated to identify the reliablemodel for applicationswith awide range ofMachnnumbers. Solutions fromtheGardiner reaction-rate set, theMoss reaction-rate set, the Park rate set of 1993, and thenDunn and Kang reaction rate are compared. High-temperature, equilibrium-constant curve fits proposed by Guptanare also examined.The newHansen’s formulation for the rate controlling temperature for the dissociation reaction isncompared with Park’s approach. Particular attention has been devoted to backward reaction rates, because thenmethods of calculation affect the flowfield structure. Sample hypersonic flowfields, typical of spacecraft reentrynconditions inwhich reactions play an important role, are presented and comparedwith results fromexperiments andnother computational fluid dynamics simulations. The differences are discussed and evaluated.