Multidisciplinary Design Optimization of Waverider-Derived Crew Reentry Vehicles

Abstract

The development of a multidisciplinary design optimization framework for crew reentry vehicles is presented. A waverider design methodology is used as the basis for the parametric design technique, with required modifications (e.g., leading edge blunting and integration of a cylindrical payload volume representing the crew compartment) used to allow the generation of practical reentry configurations. In addition to the shape design code, aerodynamics analysis, mass estimating, and trajectory/aeroheating analyses are linked using a multiobjective genetic algorithm optimization process to maximize vehicle downrange, additional payload mass capability, and lift-to-drag ratio. Pareto fronts were generated for three different launch vehicle capabilities ranging from 12,000 to 26,000 kg to orbit, and highlight the relationships between reentry vehicle payload mass, maximum lift-to-drag ratio, and downrange, as well as the fact that a medium-class or larger launch vehicle was required to meet the baseline mission payload mass requirement. Although the modifications necessary for the crew reentry vehicle mission resulted in a substantial reduction in lift-to-drag ratio relative to the idealized waveriders used in the design process, comparisons of several designs to the NASA HL-20 concept indicated that the waverider-derived design process can produce vehicles with an almost 30% improvement in maximum lift-to-drag ratio and the ability to carry additional payload mass on longer downrange trajectories.