Aerodynamic Design Optimization of a Kind of Reentry Capsule Based on CFD and Multi-objective Genetic Algorithm

This paper presents a new kind of aerodynamic shape for reentry capsule, called spherical cap cubic curve segment(SCCS) shape, which is modeled by replacing the reversing cone segment of the traditional spherical cap segment-reversing cone(SCSC) shape with a more various cubic curve segment, however the spherical cap section is retained. In the assumed allowable axial range of centroid under a designed Mach number, a multi-point/objective design optimization mathematical programming model was established against aerodynamic static longitudinal stability characteristics, hypersonic lift-to-drag ratio characteristics under trim angle of attack and off-set location placement of gravity center for the above reentry capsule. Then the aerodynamic design optimization problem of the proposed reentry capsule was investigated through multi-objective genetic algorithm(MOGA) combined numeric parallel field simulation methods, and finally the optimal Pareto front was given. Comparing with the results of the SCSC shape in the literature[1], it shows that the optimal Pareto front of the current cubic curve shape has a wider distribution range relative to the counterparts of the segment-reversing cone shape, however both are relatively close in the overlapping area.