Optimization of waverider-based hypersonic vehicle designs.

摘要

A hypersonic vehicle model based on osculating cones waverider is developed. The osculating cones waverider is designed to produce uniform flow for a two-dimensional multiple inlet ramp design. A quasi-one-dimensional combustor model with paritial equilibrium combustion is used to calculate the flow through a scramjet engine. The method of osculating cones, the off-design performance calculation of osculating cone waverider, and the vehicle model have been validated with CFD calculations. The vehicle model is used to optimize the vehicle design for Mach 10 cruise mission using the sequential quadradic programming method. The design is optimized maxium L/D, range coefficient, and cruise range for a fixed Mach 10 cruise condition. The L/D of the maximum L/D design is 4.26 which is 9.79% greater than the L/D of the maximum cruise range design; however, the cruise range of the maximum L/D design is 5.70% less than the maximum cruise range design. The design of the maximum cruise range design and the maximum range coefficient design is nearly identical for the present vehicle model. The design is also optimized for maximum range along a q{dollar}sb{lcub}infty{rcub}{dollar} = 1000 psf trajectory from M{dollar}sb{lcub}infty{rcub}{dollar} = 6 to M{dollar}sb{lcub}infty{rcub}{dollar} = 10 to assess the effects of the off-design performance on the Mach 10 designed shape. The difference between the range along the hypersonic trajectory for the optimized design and the cruise range optimized design is only 0.49%. The effects of varying the waverider design Mach number on the optimized Mach 10 cruise range design are studied. The waverider design Mach number is varied from Mach 6 to Mach 12 in increments of Mach 2. The difference in the optimized cruise range performances is less than one percent; however, the anhedral angle decreases by 28% as the design Mach number is increased which makes the Mach 12 design the most favorable in terms of structural considerations.