FFD方法在气动优化设计中的应用

本文将基于弹性体变形思想的FFD(Free Form Deformation,自由变形)方法引入飞机气动外形优化设计中,为气动优化设计提供了一种快速、有效的参数化方法和自动网格生成方法.对FFD方法的原理进行分析,归纳了FFD方法的特点;将FFD方法应用于几何外形参数化和空间网格自动生成中,建立了基于FFD方法和遗传算法的翼型优化设计系统以及基于FFD方法、遗传算法和Kriging代理模型的翼根整流包优化设计系统;分别对NACA0012翼型和DLRF4翼身组合体翼根整流包进行减阻优化设计,优化结果得到了显著的减阻成效,证明了FFD方法在气动优化设计中有很好的应用效果.

The application of FFD method in aerodynamic optimization design

The paper introduces the FFD （Free Form Deformation） method based on the elastomeric theory into the aircraft aerodynamic configuration design, which provides a quick and efficient way to parameterization geometry and generate the calculation grids automatically. With analysis of the theory, it concludes characteristics of FFD. According to use the FFD method to the parameterization and the grid generation, airfoil optimization design system based on genetic algorithm and wing cowling optimization design system based on genetic algorithm and Kriging surrogate model are established in this paper, respectively. The optimization design for drag reduction on airfoil based on NACA0012 and the wing-cowling based on wing body of DLRF4 are used to give examples there. The results of the optimization design are remarkable, which obviously proves the FFD method is useful in the aerodynamic optimization design.