Numerical Study of Spike on Blunt Nose Configuration at Supersonic Speed

A body with blunt nose moving at supersonic speed generates a strong bow shock ahead of its nose. The bow shock creates high pressure on the blunt nose surface that increases aerodynamic drag on the body. The drag force can be substantially reduced if bow shock is replaced with oblique shock by attaching a spike in front of the blunt nose. Initially,in order to observe the effect of bluntness, various configurations are analyzed. It is observed that the drag force increases nonlinearly with bluntness. Next, a validation study is carried out to benchmark simulation methodology by reproducing published work through CFD. The purpose of present study is to optimize the shape and geometry of spike in order to reduce the drag force. A nose with small bluntness has no significant drag reduction with spike. Therefore a bluntness ratio of 0.7 was selected to see a significant effect of spike on drag reduction. A disk spike is selected from reference [1] that is validated with CFD. The effect of varying spike length on drag reduction is studied. A spike length is finalized that produces lower drag force at zero angle of attack over a supersonic Mach regime. Later on, the disk spike has also been analyzed with angle of attacks.