Effects of air properties on flow filed characteristics of inflatable reentry decelerator

Abstract

Air properties are very important for predicting the flow filed characteristics of aircraft. At present, Sutherland formula is always used to predict the flow filed characteristics of inflatable reentry decelerator. However, high temperature can be observed in high speed reentry flow around inflatable reentry decelerator, thus the Sutherland formula is not suitable for reentry flow simulation of inflatable reentry decelerator. In order to investigate the effect of the air properties on the flow filed characteristics of inflatable reentry decelerator, and provides the theoretical references for the inflatable reentry decelerator design, the Gupta fitting formula and Sutherland formula are used to describe the air properties, respectively, for studying the flow filed characteristics of inflatable reentry decelerator. The results show that the reentry flow temperature with Gupta fitting formula used is lower than that with Sutherland formula used, and the temperature difference is more obvious in the high inflow Mach number and temperature cases. The results in the windward of inflatable reentry decelerator show that the Sutherland formula underestimates the heat flux and pressure, and the heat flux difference is much more obvious. Such as case 5, the peak heat flux obtained by Gupta fitting formula is by 29% higher than that obtained by Sutherland formula.