高级检索

考虑几何不确定性的瞬态动力学鲁棒性拓扑优化

Robust Topology Optimization of Transient Dynamics Considering Geometric Uncertainty

  • 摘要: 针对瞬态动力学拓扑优化中几何不确定性导致的效率与建模难题,提出一种数据驱动的瞬态动力学鲁棒性拓扑优化方法。首先采用紧支径向基函数进行材料场参数化建模,并将其支撑半径作为随机变量以描述几何不确定性;然后采用任意多项式混沌展开方法,高效计算结构最大动柔度响应的均值与标准差;最后引入基于改进格拉姆-施密特正交化的模型降阶技术缓解动力学优化中有限元分析和灵敏度求解的计算负担,显著提升了优化效率,并建立了以最大动柔度均值和标准差加权最小化为目标、体积为约束的优化模型。数值算例结果表明,采用所提方法计算得到的动柔度统计矩与蒙特卡罗模拟结果吻合良好,最大误差小于0.01。在保证计算精度的同时,该方法在单步平均耗时上较全分析方法降低约90%,计算效率显著提升。因此,该方法适用于考虑几何不确定性的瞬态动力学鲁棒性设计问题。

     

    Abstract: To address the efficiency and modeling challenges in transient dynamic topology optimization arising from geometric uncertainties, a data-driven robust topology optimization method is proposed. Firstly, the mate-rial field is parameterized using compactly supported radial basis functions, with the support radius treated as a random variable to describe geometric uncertainties. Secondly, an arbitrary polynomial chaos expan-sion method is employed to efficiently calculate the mean and standard deviation of the maximum dynamic compliance. To alleviate the computational burden of finite element analysis and sensitivity analysis in dynamic optimization, a model order reduction technique based on modified Gram-Schmidt orthonormali-zation is introduced, significantly enhancing optimization efficiency. An optimization model is then estab-lished to minimize the weighted sum of the mean and standard deviation of the maximum dynamic compli-ance under volume constraints. Numerical examples demonstrate that the statistical moments of dynamic compliance calculated by the proposed method are in good agreement with Monte Carlo simulation results, with a maximum error of less than 0.01. While maintaining accuracy, the average single-step computation time is reduced by approximately 90% compared to the full analysis method, indicating a significant im-provement in computational efficiency. Therefore, the proposed method is well-suited for robust transient dynamic design problems considering geometric uncertainties.

     

/

返回文章
返回