Aerodynamic Heating in the Gap Between a Missile Body and a Control Fin

Abstract

Aerothermodynamic loading in the gap between a generic-missile-shaped body and a control fin was investigated through computations employing the Reynolds-averaged Navier–Stokes equations. The computed results for fully turbulent Mach 6 flow were compared with wind tunnel data obtained at the Arnold Engineering Development Center in 1979 experiments. For each case, the computational mesh encompassed the full geometry. Baseline computations of the missile body, in the absence of a fin, showed reasonable agreement with experimental data for heat transfer, surface pressure, and pitot pressure. The computations captured the order of magnitude increase in heat transfer over baseline levels with the presence of the fin and connecting cylinder. In agreement with the experiments, the computations predicted that minimizing the gap height minimized heat transfer levels. The maximum computed heat transfer levels on the missile surface occurred very close to the cylinder, a region that was inaccessible experimentally. In addition, heat transfer levels on the windward surface of the cylinder, which were not explored in the experimental study, significantly exceeded those on the missile surface for larger gap heights. The intense aerodynamic heating observed for this configuration highlights the high demands for thermal protection in the gap region under a control fin on a high-speed vehicle.