考虑动力学响应的天线座拓扑-自由尺寸协同优化设计

Topology and Free Size Collaborative Optimization Design of Antenna Pedestal Considering Dynamic Response

结构的动力学响应设计是复杂装备设计与制造过程中一个不可回避的问题。针对复杂舰载天线座结构的设计需求提出了考虑动力学响应的拓扑-自由尺寸协同优化设计方法。以加权频率最大化为目标函数,简谐激励下结构的应力幅值为约束,构建协同优化模型并推导目标函数以及约束函数的灵敏度信息。针对复杂天线座结构板壳实体混合模型,进行协同设计,由拓扑优化结果确定内部材料分布,自由尺寸优化结果确定壳体的大致厚度分布,并在考虑工艺性基础上进行精确尺寸设计。随后对优化模型进行重构并分析校核。采用协同优化方法能够有效减少设计过程中的反复迭代,提升设计效率。设计结果表明,该方法能够显著提升结构的固有频率,大幅降低最苛刻工况下结构最大应力、位移幅值,实现性能更为优异的天线座结构设计。

The design of structural dynamic performance is inevitable in the design and manufacturing process of complicated equipment.A topology and free size collaborative optimization method considering the dynamic response is proposed for the design requirements of the complicated shipborne antenna pedestal structure.A topology optimization model with the maximum weighted frequency as the objective function is established,and the stress amplitude of the structure under harmonic excitation is considered as the design constraint.The sensitivity information of the objective function and the constraint function with respect to the design variables is derived.Take the antenna pedestal structure as an example,the topology-freesize collaborative optimization design is carried out for the hybrid model of solid and shell.The topology optimization results determine the internal structural configuration,and the free size optimization results determine the approximate thickness distribution of the shell.When considering manufacturability,precise size design is carried out.Subsequently,the optimization model was remodeled and checked.The proposed method can effectively spare repeated iterations in the design process to improve efficiency.The design results show that the proposed collaborative optimization method significantly improves the first three orders of natural frequencies of the structure and greatly reduce the maximum stress amplitude,displacement amplitude of the structure under the most severe operating conditions,and achieve a better structural design of the antenna pedestal.