Aerodynamic Drag Coefficient for Various Reentry Configurations at High Speed

Abstract

The drag coefficient over various reentry axisymmetric bodies is studied numerically by solving time -dependent compressible laminar Navier -Stokes equations. The governing fluid flow equations are disrectized in spatial coordinates employing a finite volume approach, which reduces the equations to semi -discretized ordinary differential equations. Temporal integration 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 a mono -block structured grid. The numerical computation is carried out for fr eestream Mach numbers of 1.2 - 6.0. The numerical scheme captures well all the essential flow field features such as bow shock wave, sonic line, and expansion fan on the corner, recompression shock wave and recirculating flow in the base region. Comparison s of the flow field, surface pressure distribution and wall heat flux results are made between different configurations of the reentry capsules such as ARD (ESA’s Atmospheric Reentry Demonstrator), CARINA, Apollo, Muses -C (Mu Science Engineering Satellite) , OREX (Orbital Reentry Experiments), Beagle -2 and spherically blunted cone configurations. The effects of geometrical parameters of the different reentry capsules on surface pressure and forebody aerodynamic drag are analyzed. Base pressure is independent of the forebody shape of the reentry capsules. The effects of module geometry on the flow field are numerically analyzed which may be useful for optimization of the reentry capsule.