多种约束条件下机翼的双目标响应面优化方法

Multi-objective Wing Optimization under Constraint Based on Response Surface Method

提出一种在较强的工程约束条件下,开展机翼优化设计的高效率多目标方法。综合升力线理论和RANS的流场计算方法以及数学近似的响应面方法,研究在多种工程约束条件下,巡航设计点中升阻比和翼根弯矩的多目标优化问题。采用分步嵌套优化的方法,首先,固定平面形状,优化展向的扭转角分布;然后优化固定形式下的平面形状参数,对于每一个平面外形,展向扭转角分布的优化为平面形状优化的内迭代;最后通过响应面的结果得到双目标的近似Pareto锋面。该方法对完成特定约束条件下的气动设计具有参考价值。

A multi-object optimization is carried out considering wing lift-to-drag ratio and bending moment performance at cruise flight condition using a combination of lift line theory, CFD RANS calculation and response surface methods. Wing is optimized under strong engineering constraints with constant planform topology, reference area, and wing root chord length. The airfoil shapes are also kept the same along the span. The optimization work is conducted in two steps. Spanwise twist angle is optimized at fixed wing planform at first. Wing planform is then optimized with wing twist optimized in the inner loop. Pareto front for the two objectives are obtained based on a response surface methods. The method presented in the paper can be used in cases where there are strong engineering constraints in wing optimization problems.