Design Optimization of Spikes Based on Aerodynamic-ballistic Coupling Method

Abstract

The spike installed on the blunt-nosed body pushes the strong bow shock away from the body surface in supersonic speed, which forms recirculation flow with low pressure ahead of the body surface, and then decreases the drag, and the landing velocity of the rocket can be increased. Aiming at this problem, the effect of the spikes shape parameters on the drag induction and its flow mechanism were simulated. Based on the aerodynamic-ballistic coupling method, the spikes shape parameters were optimized to increase the landing velocity. The results show that the additional drag of the spikes is larger, and there is no drag reduction in subsonic speed and transonic speed. The drag reduction of the spikes is remakable in supersonic speed, and the optimal shape lengths increases, and the radius decreases with the increase of the Mach number. Based on the coupling method considering the effect of the drag aerodynamic of the spikes on the ballistics, the landing velocity and the range after optimization can be increased by 10.0% compared with the initial shape. In the calculation range, the effect of the spikes is little on the lift characteristic and the static stability.