Drag reduction method for supersonic missile based on Busemann biplane concept

Wave drag caused by the strong shock is unfavorable and inevitable for the supersonic flight of aerodynamic vehicles. Busemann biplane concept is presented which can markedly reduces the wave drag by the shock wave and expansion wave interference, as well as the weakening of the shock wave due to the decrease of airfoil thickness. To a model of the aircraft shaped missile, numerical results of the inviscid flow show that the drag of the model using Busemann biplane is reduced more than 42% at its designed Mach number compared to that using the diamond airfoil. Busemann biplane with morphing technology is studied to avoid the choked flow at its off-design condition, through which the ratio of the section areas of the inlet and the throat is controlled and consequently the amount of wave drag produced by Busemann biplane is suppressed to close to that of the diamond airfoil. Moreover, Licher biplane concept based on Busemann biplane that consists of two unsymmetrical elements could further improve the aerodynamic performance at the desired lift condition. The overall results obtained show that the drag-reduction method presented will provide a new approach for the research and development of the supersonic missiles.