Three-Dimensional Inviscid Flowfield Computation Over Various Reentry Configurations

Abstract

*The flow field analysis over various reentry configurations is studied numerically by solving time -dep endent compressible three -dimensional Euler equations. The governing fluid flow equations are discretized in spatial coordinates employing a finite volume approach, which reduces the equations to semi -discretized ordinary differential equations. Temporal i ntegration is performed using multi -stage Runge -Kutta time stepping scheme. A local time step is used to achieve steady state solution. The numerical simulation is carried out on structured grid without employing multi -block mesh arrangement. The numerical computation is carried out for freestream Mach numbers range of 1.2 - 10.0 and angle of attack up to 10 degree. The thermodynamic and transport properties are considered as a function of temperature using Hansen’s table. The flow features around the reent ry body are characterized by a bow shock, expansion fan and base flow region. The numerical scheme captures all the flow field features well such as bow shock, expansion fan and downstream recompression shock. Comparisons of the flow field and surface pres sure distribution results are made between different configurations of the reentry capsules such as ARD (ESA’s Atmospheric Reentry Demonstrator), Apollo II, OREX (Orbital Reentry Experiments) with and without shoulder radius, MUSES -C and spherically blunte d cone with flare angle of 25, 30 and 35 degree. A comparison between present numerical results and with the Newtonian flow assumptions for the forebody drag of the reentry capsules are made for the freestream Mach number 10 and the comparison shows a goo d agreement between them.