Effects of steady flow heating by arc discharge upstream of non-slender bodies

Influence of steady energy addition into the flow by low-voltage DC-arc discharge located upstream of conically-nosed and spherically-blunted bodies was investigated experimentally in the Ludwieg-Tube Facility at Mach 5. The results include drag force measurements and shadowgraph flow visualizations. The flow-field structure, arising due to the bow-shock / heated-wake interaction, as well as the bow-shock intensity and heating power effects on the drag reduction are analyzed in this paper. The results demonstrate the existence of an optimum heating rate, providing a maximum effectiveness of energy addition and showing a distinct drag reductions up to 70% dependent on test conditions and model geometries