【摘要】 准确的有限元模型对于天线梁结构的设计与性能优化具有重要的工程价值，其核心在于精准掌控天线梁的共振频率区间以避免线路激励引发的共振问题。尽管天线梁结构较为简单，参数相对单一，但构架端部刚度与约束条件的影响导致有限元模态分析结果与试验数据存在显著偏差。为建立更为精确的天线梁有限元模型，通过层级模态试验逐级探讨了引起模型偏差的主要因素。研究表明，建模误差的关键在于天线梁边界条件的设置不当。为解决该问题，采用粒子群算法修正边界约束参数。修正后的天线梁模态频率与试验模态频率平均误差降至2.11%,关键的横梁垂弯模态频率仅相差0.76%。修正后的天线梁有限元模型可为后续结构优化设计提供可靠的基础与工程价值。更多还原

【Abstract】 Accurate finite element models have important engineering value for design and performance optimization of antenna beam structures, and these models’ core target is precisely controlling resonance frequency interval of antenna beam to avoid resonance problems caused by line excitation. Although antenna beam structure is relatively simple with fewer parameters, effects of end stiffness and constraint conditions of structure cause significant deviations between finite element modal analysis results and test data. Here, to establish a more accurate finite element model of antenna beam, main factors to cause model deviation were explored step by step with hierarchical modal tests. Study showed that the key to modeling errors lies in improper setting of boundary conditions for antenna beam. To solve this problem, the particle swarm optimization algorithm was used to modify boundary constraint parameters. It was shown that after modifying, the average error between the modified antenna beam modal frequencies and test modal frequencies is reduced to 2.11%, the deviation between finite element modal analysis result and test value for the critical beam vertical bending modal frequency is only 0.76%; the modified finite element model of antenna beam can provide a reliable foundation and engineering value for subsequent structural optimization design.更多还原