Experimental investigation of heat transfer over double disk spike-blunt body at Mach 5.7

Abstract

The forefront research in the territory to the regime of hypersonic flow is intended to focus on improving the overall performance of the existing aerospace vehicle. Two major hindrances for the development of an effective high speed vehicle are aerodynamic drag acts against the vehicle and heat transfer rate on the body. In this study, we explore the possibility of addressing this issue by placing an aerospike at the nose portion (i.e., stagnation region) of the high speed vehicle and as a result, wave drag of vehicle is considerably reduced. However, this will lead to the increase in heat transfer at the localized spot of the main body. In an attempt to reduce this localized high heat transfer, the current study evaluates the variation in the heat transfer on the body, by modifying the spike through the addition of a smaller hemisphere on the mid-section of the aerodisk spike. In this regard, shock tunnel experiments and computational studies were carried out on this modified spike configuration, termed as “double-disk spike” or “double spike”. The experimental results indicate that heat transfer near the localized spot of the blunt body with spike decreases for a double spike case in comparison to single disk spike. The decrease in heat transfer varies from 5% to 30% depending on the double spike configuration (i.e. varying cap radius and length of the spike). To supplement these results, 3D Finite Volume simulation, “HiFUN” (High Resolution Flow Solver on Unstructured), showed a good trend in heat transfer compared to that obtained from the experiment; it was found that simulated drag from the double spike is less than single spike case.