在飞行器设计过程中为了提高优化设计的寻优精度，设计变量不断增加，从而使整个过程更加复杂且大幅延长设计周期。针对这一问题，基于本征正交分解降阶方法开展气动外形设计空间重构方面的研究。工作针对二维翼型开展，主要目标分为2个方面：①减少优化过程中的气动外形设计参数；②提高设计空间中满足设计约束的样本比例。在Hicks⁃Henne参数化和POD重构得到设计空间内随机选择20000个样本发现，Hicks⁃Henne参数化空间中满足设计约束的样本比例不足25％，而重构之后的空间则超过70％。因此，采用P OD方法对设计空间进行重构大大提高了样本质量，同时减少了优化设计参数。以RAE2822进行厚度约束下的单目标升阻比增大优化设计为例分别研究传统的约束处理方法和设计空间重构对优化结果的影响。传统约束处理方法中包括罚函数法和拒绝策略，优化结果表明拒绝策略略优于罚函数法，且无须设置惩罚权重，使用方便。对比重构前后设计空间的优化结果可见，2种传统约束处理方法在32个Hicks⁃Henne参数化空间中最优设计结果升阻比增加分别为27�61％和28�20％，采用P OD方法重构后的设计空间得到的升阻比提升分别为28�20％和30�63％。因此，设计空间重构前后的优化精度基本类似，而且设计空间重构之后优化设计参数大大减少，设计效率得到明显提升。%In order to increase optimization precision in the design process of aircraft, the design parameters have augmented;this makes the design process more complicated and extends the design cycle. Aiming at this issue, re⁃construction method of aerodynamic design space using Proper Orthogonal Decomposition is investigated. Main ob⁃jective is divided into two aspects: one is reduction of the number of aerodynamic design parameters in design process, the other is increase of the ratio of samples which satisfy design constraints. In the Hicks⁃Henne parame⁃terization space and reconstructed space by POD, 20000 samples are chosen by LHS method. It is illustrated that the ratio of Hicks⁃Henne parameterization space satisfying thickness constraints is less than 25%, while the ratio of reconstructed space by POD is about 70%. Therefore, after space reconstruction by POD, sample quality is en⁃hanced significantly. Moreover, the number of optimization parameters is decreased. The influence of traditional constraint handling methods and reconstructed design space is investigated with the optimization of Cl/Cd of RAE2822 airfoil. Traditional constraint handling methods include penalty function method and death penalty. It is shown that death penalty method is slightly better than penalty function method from optimization results. Addition⁃ally, there are no penalty factors in death penalty process, which is convenience to use. Comparing the optimization results before and after reconstructed design space, the improvements of Cl/Cd are 27�61% and 28�20% respec⁃tively for two traditional penalty handing methods in Hicks⁃Henne parameterization space, while the improvements are 28�51% and 30�63% respectively in reconstructed design space by POD. Therefore, the optimization precision is almost the same before and after space reconstruction, and the number of design parameters is decreased by half;this makes design efficiency improve significantly.
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