Investigation of an Axisymmetric Spiked Body in a Hypersonic Shock Tunnel

Abstract

The forefront research in the regime of hypersonic flow is intended to focus on improving the overall performance of the existing aerospace vehicles. A high-speed vehicle experiences a high level of aerodynamic heating and drag. These vehicles are also characterised by shock impingement on the body and shock-shock interaction closer to the body surface, which cause pressure and thermal loading. With the addition of a spike on the main body, the flow field over high-speed vehicles can be changed drastically, which would create an impact on the heat flux and aerodynamic drag at hypersonic speed. The aerospike with a hemispherical blunt body and the sharp tip spike over a flat-faced cylinder are two types of spike configurations with different flow phenomenon that are studied in this investigation. The first part of the study focuses on exploring the possibility of addressing aerodynamic drag and heat transfer on a body by placing an aerospike at the nose (i.e., stagnation region) of the high-speed vehicle and as a result, wave drag of a vehicle is considerably reduced. However, this can lead to an increase in heat transfer at localized spots of the main body. An attempt is made in the current study to reduce these localized high heat transfer spots and evaluate the variation in both heat transfer and drag on the body, by modifying the spike configuration through the addition of a smaller hemisphere midway along length of the aerospike. In this regard, shock tunnel experiments and computational studies are carried out on this modified spike configuration, termed a double-disk spike or double spike. The experimental results show that the heat transfer rate near the localized spot of the blunt body with spike decreases for a double spike in comparison with a 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, the 3D Finite Volume solver,...