中文摘要：

阐述了飞行器耦合系统优化设计所面临的计算问题，包括计算量大，计算精度低等。分析指出了产生这些问题的原因在于计算中存在两重嵌套的循环。在上述分析基础上，提出逐步逼近的优化设计方法，在该方法中构造了一个非耦合的近似模型，并针对该近似模型进行优化计算，这样做将嵌套的两个循环过程转化为序列进行的两个循环过程。同时为了在保证精度的前提下提高计算效率，构建了一种近似模型逐步逼近真实模型的迭代格式。仿真算例表明了本方法的有效性。

英文摘要：

The reason for the computational difficulties in the flight vehicle coupled system optimal design is analyzed. The analysis shows that there are two nested iteration loops in the computation of coupled system optimization, that is, the outer loop of the optimization and the inner loop of solving coupled equations. The computational scheme of the nested iterations results in high amount of computation and low accuracy. Based on the analysis, a sequential ap- proximate optimization method is presented. In this method an approximate uncoupled model of the original coupled system is constructed by using the response surface method, and the optimization is then performed based on the ap- proximate uncoupled model. To ensure the accuracy of the approximation, the uncoupled approximate model is refined at each iteration by using the optimum point of previous iteration. A numerical example of an unmanned aerial vehicle （UAV） wing design shows the effectiveness of the presented method.