Aero-structure coupled optimization for high aspect ratio wings using multi-model fusion method

To effectively solve the aero-structure coupled optimization problem of high aspect ratio wings, a multi-model fusion method is enhanced and utilized in this paper. First, considerable efforts are spent on aero-structure coupled analysis using computational fluid dynamic (CFD) and finite element analysis (FEA) methods with various levels of fidelity (i.e., coarse and fine grids). Then an enhanced multi-model fusion method is developed to improve the efficiency of aero-structure coupled optimization. The enhanced multi-model fusion method integrates the limited high-fidelity (HF) simulations with a large number of low-fidelity (LF) simulations to create a surrogate model with preferable accuracy. Moreover, the enhanced multi-model fusion based aero-structure coupled optimization strategy is proposed. Finally, the proposed optimization strategy is tested by solving a high aspect ratio wing aero-structure coupled optimization problem. After optimization, the overall performance including lift-to-drag ratio and structure weight is significantly improved. Compared with Kriging-based optimization method using pure high fidelity model, the enhanced multi-model fusion based optimization can achieve a better optimization result under the same computational cost, which illustrates the effectiveness of the proposed enhanced multi-model fusion based optimization strategy in solving aero-structure coupled optimization problems of high aspect ratio wings.