Abstract:The waverider configuration has a broad application in hypersonic vehicles due to its high lift-to-drag ratio ( L/ D). In actuality, the sharp leading edge must be blunted because of the serious aerothermal heating problem, which can lead to significant loss of aerodynamic performance. Thus, the optimum configuration with sharp leading-edge cannot guarantee that it is still optimum after being blunted. To solve the problem, this paper first studies the influence and mechanism of leading-edge bluntness on the lift and drag characteristics of different configurations. The results show that the bluntness causes the lift to decrease slightly, the drag to increase greatly, and the L/Dto decrease significantly. The wave drag of the blunted leading-edge plays a dominant role in the total drag increment, and the friction drag of the blunted leading-edge is very close to the friction drag reduction of the upper and lower surface. Based on the above results, this paper evaluates the wave drag of the blunted leading-edge by the modified Newton theory, and combines the aerodynamic models of sharp leading-edge waverider and genetic algorithm to obtain the optimum configurations with blunted leading-edge. The aerodynamic forces of the optimum configurations are evaluated via CFD simulation. The results show that under the constraints of different flight altitudes, different lift, and different blunt radii, compared with the optimum configurations with sharp leading-edge, the blunted optimized waveriders have the characteristics that the width is smaller, the sweep angle at the same longitudinal position is larger, and the L/Dis higher. At the design condition of M _∞= 15, H= 50 km and CL= 0.3, the L/Dof the optimum blunted configuration with R= 10 mm can be improved by 9.32%. What’s more, as the constraint of the lift coefficient increases, blunt radius increases, and the flight altitude decreases, the advantage of L/Dfor the blunted optimized waveriders become more evident.