Hypersonic Flow over Hemispherical Blunt Body with Spikes

Abstract

Use of spike on a hemispherical body changes the flow fi eld and hence the aerodynamic drag. Computational studies have been made to obtain the fl ow fi eld around a hemispherical body with spikes at a hypersonic Mach number of 6. The eff ect of shape of spike tip and length has been studied. Laminar computations have been made adopting structured grid using commercial software Fluent. It is observed that use of a sharp spike itself reduces the drag signi cantly. However the use of a hemispherical head spike further reduces the drag. Contribution of di erent components towards drag indicate that the increase in length of a spike do not change the spike contribution. However the flow field on main body is altered which leads to reduction in dragwith change in length. Estimated maximum drag obtained is found to be highest in comparison to any reported drag value in literatures with any spike shape and length.