Thermal Non-equilibrium Effects on Spherically Blunted Cone Flows

Abstract

Spherically blunted cones are commonly utilized as re-entry or entry capsules. Depending on the cone angle, the shock shape is either dominated by the spherical nose or the conical part. To understand the shock shape transition behaviour in more detail, a systematic numerical, experimental and analytical study is currently conducted. As part of this, experiments performed in the High Enthalpy Shock Tunnel Göttingen, HEG of the German Aerospace Center are combined with numerical studies conducted with the DLR TAU code. The comparison of the measured and computed shock stand-off distance clearly shows the influence of the different physico-chemical models used in the TAU code. The measured values are best fitted by the assumption of a chemical and thermal non-equilibrium flow. Further, the measured and computed drag force and the computed variation of surface pressure and wall heat flux distrinution as function of the cone angle is discussed.