最临界准则法在复杂结构优化中的应用研究

STUDY OF THE MOST CRITICAL CRITERION METHOD FOR COMPLEX STRUCTURE OPTIMIZATION

运用虚功原理推导最临界准则法在复杂大型混合结构上的优化准则公式,并结合飞行器结构优化设计的特点,对该算法在多工况、多约束下的实现进行探讨,扩展最临界准则法的应用范围。对该算法编制通用的计算机程序,运用其对一机翼结构进行算例验证,同时运用成熟的商业软件iSIGHT中可行方向法对算例进行优化,并对优化结果、耗时等进行对比,两者优化结果一致,从而证明对该算法扩展的正确性;而优化耗时方面最临界准则法明显优于可行方向法。该扩展后的算法已在某型号飞机的机翼主承力结构优化设计上得到运用。结果表明,扩展后的最优准则法通用性强,易于实现,优化耗时短,是一种实用的工程优化方法。

The criteria formula used on rod and shell mixed structure based on the most critical criterion was derived using principle of virtual work.Discussions and extensions were made to the algorithm under multi-load cases and multi-constraints situations according to the characteristic of aircraft structure optimization design.Verifications were carried out through an experiment on a wing structure optimization problem using the proposed method and the feasible direction method from iSIGHT software.Experimental results indicated that the proposed method could obtain results in accordance with iSIGHT,proved its correctness,while consumed less time.The proposed method had been applied to the optimization of main load-carrying wing structure and the results are satisfactory.Both the experimental and practical result shows that the proposed method is an effective,fast and practical engineering optimization method.