Coupled investigation on drag reduction and thermal protection mechanism of a double-cone missile by the combined spike and multi-jet

Abstract

Vehicles flying at supersonic/hypersonic speeds would encounter severe aerodynamic and aerothermodynamic environment, and hypersonic vehicles would produce high pressure and heat flux loads. In this work, the fluid-thermal coupling analysis is performed on the double-cone missile. The spike, as well as the combined spike and multi-jet strategy are applied to the blunt head of the missile for drag reduction and thermal protection. The impacts of the jet pressure ratio (PR) and length-to-diameter ratio (L/D) on the flowfield and the aerodynamic characteristics are investigated numerically. The obtained results reveal that the heat flux and static pressure can be reduced significantly by increasing the jet pressure ratio, and the maximum peak pressure and heat flux decrease up to 58.21% and 46.43% respectively. The flow field structure highly depends on the length of the spike, and the total drag coefficient is not monotonically reduced with the increase of the length of the spike. Moreover, it is noted that the aerodynamic heating level and the drag value are both related to the reattachment angle of the reattachment shock wave.