Numerical simulation of Galileo Probe entry flowfield with radiation

Radiation coupled calculation of Galileo Probe entry flowfield is carried out by solving the Navier-Stokes equations assuming thermochemical equilibrium. A multi-band model having 570 wavelength points is employed in the radiation calculation. It is found that the radiative and convective heat fluxes obtained in the present calculations agree well with the preflight calculation for the initial time of the entry flight. However, at later time, the radiative heat flux is underestimated while the convective heat flux is overestimated in the present results. This is due to the fact that the present calculation does not take account of shape change due to ablation along the flight trajectory. It is shown that the shock standoff distance at the stagnation point decreases about 4% when radiative cooling effect is accounted for. A newly developed parallel strategy for radiative transfer calculation is found to achieve a higher speedup ratio than that given by the earlier wavelength division strategy.