Aerodynamic shape optimization of wing-body-tail configuration via efficient surrogate-based optimization

In this paper, we perform the aerodynamic shape optimization of the Common Research Model (CRM) wing-body-tail configuration via efficient surrogate-based optimization rather than the gradient-based optimization which has been widely used in previous work. The full-potential equation in conjunction with viscous correction method is used to simulate the transonic flow in optimization. Two optimization strategies are investigated in this paper. The first one is that the wing-body-tail configuration is optimized without considering the trim constraint at first, then the optimized configuration is trimmed manually by deflecting the horizontal tail. The second strategy is considering the trim constraint simultaneously during the optimization. In both cases, the lift coefficient is fixed at 0.5 and 483 geometric thickness constraints are enforced to guarantee that the thickness of wing are greater than or equal to 25% of the baseline geometry, while a wing volume constraint is also enforced to guarantee that the wing volume values are no less than that of the baseline geometry. There are 39 design variables in the first case, while the number for the second case is 40 because of the consideration of the horizontal tail’s deflecting. The results show that considering the trim simultaneously during optimization can obtain an optimal wing, whose drag is 1.5 counts lower than that optimized without considering trimming.