随机振动响应下的组件结构布局优化设计

Layout Design Optimization of Component Structure with Random Vibration Response

从工程应用需求出发,研究了随机振动载荷作用下的组件结构布局优化问题。提出采用有限包络圆族描述组件外形轮廓的近似方法,有效解决了设计过程中预防组件干涉的问题;建立了随机振动响应分析有限元模型,并对模型进行了实验验证与结果分析。在此基础上,以随机振动载荷下特定点自由度响应均方根(RMS)值之和最小为目标函数建立了组件布局通用优化设计模型,研究了单一组件与4组件问题的布局优化问题,并分别采用梯度优化算法和遗传算法进行优化求解比较研究。结果表明,所提出的设计方法能够有效地实现随机振动响应下的组件结构布局优化设计,两种优化算法均能显著降低结构关键部位的动力学响应。

This article is focused on the component layout design optimization under random excitations to fulfill the requirements of engineering applications. In order to solve problems related to the overlapping of compo nents during the design process, finite circle approximations are proposed to describe the exterior contour of each component. Furthermore, a finite element model is established to predict the responses under random ex citations. The model and the numerical results are validated experimentally. Based on this, a general optimization model is established by defining the objective function as the minimization of the sum of the root mean square （RMS） response measured on the degrees of freedom （DOFs） of specific points of the components. Layout optimization problems with one component and four components are studied. The gradient optimization algorithm and genetic algorithm are used to solve both problems. The results show that the proposed method can deal efficiently with the layout design optimization of component structures with random vibration responses. Both optimization algorithms can reduce significantly dynamic responses at key locations of the component structure.