蒙皮拉形加载轨迹优化

对双曲度飞机蒙皮拉伸成形问题,探讨了加载轨迹对成形质量的影响,提出了采 用最优化理论与算法和有限元数值模拟相结合,确定最优拉形加载轨迹的原理与方法.分析 了单凸双曲度蒙皮拉伸成形常用加载轨迹的成形特点和不足,采用有限元数值模拟和序列二 次规划相结合的方法,通过正交试验设计建立近似响应模型和设计变量的取值范围,以减小 卸载回弹提高贴模度为研究目标、最大主应变为约束条件建立最优化数学模型,确定最合理 的拉形加载轨迹.优化结果表明成形零件贴模度和应变分布与厚度的均匀程度均有明显提高 . 

Optimization of loading trajectory in skin stretch forming process

The influence of loading trajectory was discussed to solve the precision forming problem of double curve skin in stretch forming.The method of combing finite element analysis and optimization algorithms was proposed to acquire the reasonable loading trajectory.Characteristic and insufficiency of common loading trajectories were analyzed which used in double curve skin forming.Optimization mathematics model was set up in order to reduce springback and improve the fittability.Approximate model and variables range were set up with orthogonal design.The reasonable loading trajectory was found through the numerical simulation and sequential quadratic programming optimization algorithm under the restrictive of maximal thickness strain.The optimization results show that the fittability,strain distributing and thickness uniformity were improved greatly.