Hypersonic blunt-body shape optimization for reducing drag and heat transfer

Alarge design concern for high-speed vehicles such as next-generation launch vehicles or reusable spacecraft is the drag and heat transfer experienced at hypersonic velocities. In this paper, the optimized shapes for both minimum drag andminimum peak heat flux for an axisymmetric blunt body are developed using computational-fluid-dynamics software in conjunction with a genetic algorithm. For flowfield calculations, the commercial flow solver ANSYS Fluent is employed to solve the unsteady compressible Reynolds-averaged Navier-Stokes equations in conjunction with the shear-stress transport k-ω turbulence model. The hypersonic body shape is optimized using a multi-objective genetic algorithm to minimize both the drag and heat transfer. The multi-objective genetic algorithm creates a Paretooptimal front containing the optimized shapes for various relative objectives of minimized drag and heat transfer. The results show a significant decrease in both the drag and peak heat flux and exhibit the expected changes in the body profile. It should be noted that shape optimizations of a blunt body in hypersonic flow for reducing both drag and heat flux through use of a multi-objective genetic algorithm are reported in this paper for the first time in the literature. The proposed methodology will allow the simulation and optimization of more complex shapes of hypersonic vehicles.