Multi-objective design optimization of the combinational configuration of the upstream energy deposition and opposing jet for drag reduction in supersonic flows

Abstract

Optimization design has been widely used in the supersonic vehicle design process and the drag reduction characteristic is an important objective of the optimization. The drag reduction mechanism applied to the blunt body with the combinational configuration of the upstream energy deposition and opposing jet for drag reduction has been conducted numerically. In the current study, the three-dimensional coupled implicit compressible Reynolds Averaged Navier-Stokes equations and Menter's shear stress transport turbulence model are employed to simulate the flow fields around the blunt body with the combined method. The results show that in the jet-to-freestream total-pressure ratio of 0.2 and 0.4, the drag is reduced by 47.44% and 45.96%, respectively. Further, the Latin hypercube method is used for the generation of initial samples for optimization and the multi-objective design optimization algorithm coupled with the Kriging model surrogate model is applied to determine optimal flow control parameters. The drag reduction factor Rd and drag reduction effectiveness Eeff are selected as optimization objectives. The Pareto-optimal front for the multi-objective design optimization results is acquired and there exists a challenging tradeoff between the two optimization objectives. The drag reduction factor Rd and drag reduction effectiveness Eeff further increase as much as 28.16% and 116.47%, respectively. The jet has a stronger penetration in the optimum design condition, and the findings suggest that the strategy of adding energy spot to the upstream flow field of the opposing jet can be an effective way for drag reduction.