考虑多巡航工况的大型飞机气动弹性优化

Aeroelastic optimization of large aircraft considering multiple cruise conditions

针对目前大型飞机机翼常见的单点优化设计方法在考虑多巡航工况情况下非设计点性能较差的问题,提出了一种多工况气动弹性综合优化框架,考虑了不同的巡航工况,对大型飞机复合材料机翼开展气动弹性优化的研究。以最小机翼结构质量为目标,在气动弹性、应力/应变、强度等条件的约束下,通过遗传算法对机翼型架外形的蒙皮、腹板、凸缘等复合材料部件的铺层厚度展开设计,并根据优化结果进行了型架外形设计,采用高精度CFD/CSD耦合方法分析和校验了优化结果的升阻特性。研究表明:在不低于设计巡航外形气动性能的条件下,综合多巡航工况的气动弹性优化能有效减轻结构质量,从而减少整体燃油消耗。进一步对比分析了多巡航工况优化与单巡航工况优化,研究了巡航工况数目与优化结果之间的关系,结果表明:综合考虑多巡航工况的优化结果性能更好,且优化结果的整体性能随着优化巡航工况数目的增加而提升。

Aiming at the problem of poor performance at off-design points in the current common single-point optimization design method of large aircraft wings considering multiple cruise conditions, a synthetical aeroelastic optimization framework with multiple cruise conditions is proposed, and the multi-point aeroelastic optimization of a large aircraft composite wing is studied. The laminate thickness of skin, web, flange and other composite components of the jig shape is optimized to minimize the wing structure weight using genetic algorithm, subjected to the constraints of aeroelasticity, stress/strain, strength and other conditions, and the jig shape design is carried out according to the optimization results. The lift-to-drag characteristics of the optimization results are analyzed and verified by the high-precision CFD/CSD coupling method. The results show that the multi-point aeroelastic optimization can effectively reduce the structure weight and maintain the aerodynamic performance of the pre-designed cruise configuration, thus reducing the overall fuel consumption. Furthermore, the results of multi-point optimization and single-point optimization are compared and the relationship between the considered cruise conditions number and the optimization results is analyzed. The results show that the performance of the multi-point aeroelastic optimization is better than that of the single-point aeroelastic optimization, and the overall performance increases with the increase of the number of cruise conditions considered in the optimization.