基于直接控制FFD参数化方法的跨声速层流翼身组合体稳健性设计

Abstract

The geometric shape is not directly manipulated by free-form deformation (FFD) technique. A high level FFD control volume is always adopted in the refined aerodynamic design. The direct manipulated free-form deformation (DFFD) technique is developed in this paper to improve the shortcomings of the FFD technique. This method adopt a parameter identification technique which can identify the disturbance quantities and convert them into displacement values on the FFD control lattices. The DFFD technique can accomplish refined aerodynamic shape design using less design variables. The visual impression is much better than the traditional FFD technology, and the number of the design variables is not increased with using of the high level FFD control volume. The robust design system is established by DFFD technique, multi-groups collaboration particle swarm optimization (MCPSO) and adaptive sampling algorithm, combined with quaternion mesh deforming technique and the numerical simulation of boundary layer transition based on γ - Re θt transition model. A transonic laminar wing body is optimized by this system. The design results show that not only a wide range of laminar flow area is maintained, but also the development of shock is controlled.