DOI: 10.36347/sjet.2024.v12i07.001

Pages: 192-219

A forward-facing spike attached to a hemispherical body significantly alters its flow field and influences aerodynamic drag at high-speed flow. Consequently, the geometry, that is, the length and shape of the spike, has to be investigated in order to obtain a large conical recirculation region in front of the hemispherical body to get beneficial drag reduction. It is, therefore, a potential candidate for aerodynamic drag reduction for a future high-speed spiked hemispherical body. Axisymmetric compressible time-dependent Navier-Stokes equations are solved employing a finite volume discretization in conjunction with a multistage Runge-Kutta time stepping scheme. The effects of the spike length and shape, and the spike nose configuration on the reduction of drag are numerically evaluated at Mach 6 at a zero angle of incidence. Semi-cone angle of conical spike varied from 10o to 30o are to get the different type of flow field such as formation of conical shock wave, separation region and reattachment of shock wave are analyzed in conjunction with flat-disk spike and hemispherical disk spike attached to the hemispherical body. The bow shock distance ahead of the hemispherical and flat-disc is compared with the analytical solution and good agreement found between them. The influence of the reattachment shock wave generated from different spike shape are is used to understand the cause of drag reduction fluid mechanics.