A locally validated surrogate-assisted design strategy for a hypersonic waverider under coupled aerodynamic and aerothermal constraints

This study aims to develop and assess a physically interpretable, locally validated surrogate-assisted design strategy for a hypersonic waverider under coupled aerodynamic and aerothermal constraints. Hypersonic waverider design requires aerodynamic efficiency and preliminary aerothermal feasibility to be resolved within a coupled and physically interpretable framework. This study presents a bounded local design investigation for a hypersonic waverider at Mach 10, 30 km altitude, and α=4^∘, using a physics-based evaluation chain, local design-space refinement, target-specific surrogate modeling, and post-optimization full-physics reevaluation. The local problem is defined by four geometric variables: shock angle β , width-to-length ratio W / L , leading-edge radius r_le , and shaping exponent n_power . The results show that β and W / L act primarily as aerodynamic performance drivers, whereas r_le acts mainly as a thermal-feasibility variable with only weak influence on L / D over the examined local range. The best feasible solution is boundary-controlled rather than interior, occurring near the upper bounds of β, W / L , and n_power , and near the smallest thermally admissible value of r_le . Two final reference designs are retained: a peak feasible point and a recommended nominal point. The nominal design preserves nearly the same aerodynamic efficiency as the peak feasible design while increasing the thermal margin from 0.19 to 4.04 W/cm². A local surrogate framework trained only within the trusted four-dimensional design box reproduces the optimizer-relevant structure of the problem under random hold-out, blocked hold-out, and post-opt reevaluation. Both retained reference points are shown to remain within the nominal admissible hypersonic flight corridor, while a heat-flux-bias sensitivity check indicates that the recommended nominal point has a larger screening-level thermal reserve. These results establish a physically interpretable and locally validated surrogate-assisted design strategy for hypersonic waverider development under coupled aerodynamic and aerothermal constraints.