Shockwave Oscillations Over the Conical Heat Shield Region of a Typical Launch Vehicle at Mach 0.95

Abstract

AbstractThe occurrence of shock wave over the typical launch vehicle model with conical heat shield at a free-stream Mach number of 0.95 was studied using flow visualization techniques. Both oil flow pattern, as well as shadowgraph image techniques, have been used to trace the flow features over the model. The study was conducted at a various angle of attack from 0\({^{\circ }}\) to 4\({^{\circ }}\) in steps of 1\({^{\circ }}\). Instantaneous shadowgraph images of shock wave pattern over the surface of the conical heat shield region were captured using a highspeed camera. The image shows a series of compression weak waves which forms a standing normal shock wave on the heat shield region at angles of attack of 0\({^{\circ }}\), 1\({^{\circ }}\), and 2\({^{\circ }}\). Further increase in angle of attack, the normal shock wave splits into lambda-shaped shock pattern. At an angle of attack 3\({^{\circ }}\) and 4\({^{\circ }}\), shock-induced separation and reattachment process result in shock oscillations along the surface of constant heat shield cylindrical region. The frequency of shock wave oscillations was found to increase with the angle of attack from 3\({^{\circ }}\) to 4\({^{\circ }}\). The oil flow pattern clearly evident that the average distance covered during the shock oscillations.KeywordsNormal shock waveLambda shock waveSeparated flowShockwave oscillations