| A method has been developed to predict three-dimensional hypersonic laminar or turbulent shock-layer flows for perfect gas or equilibrium air. This allows the calculation of moments and forces on a reentry vehicle throughout the entire reentry trajectory. A two-layer eddy-viscosity model is used for the turbulent regime. The thermodynamic and transport properties for air are obtained by interpolation within a two-dimensional table or from curve-fit data. Comparisons are made for air in chemical equilibrium and perfect gas for a seven-degree spherically-blunted cone at various flight altitudes with a cold, moderately cool and an adiabatic wall for angles of attack up to twenty degrees. Also comparisons are made for laminar and turbulent calculations at 40,000 feet of altitude. Wall heat-transfer, wall pressure, force and moment coefficients and execution times are compared for some sample cases. This method can be used to predict viscous flow in chemical equilibrium over axisymmetric reentry vehicles at angles of attack up to twenty-five degrees. |
