Abstract: Automobile radiator is one of the important parts of vehicle thermal management, which is prone to resonance and noise during vehicle driving, which may lead to leakage and other failures. This problem can be avoided by modal analysis in the design stage. Three methods are used to construct the finite element model of the heat exchanger, and the modal analysis is carried out. The first-order modal frequencies of the three methods are 80.89 Hz, 82.116 Hz and 108.94 Hz respectively. The formation differences of the two methods with similar first-order modal frequencies are compared, and the two methods with higher solving accuracy are finally determined. Based on these two methods, the first three mode frequencies of the heat sink in the actual working condition are solved, and it is found that the mode frequency is reduced, which is consistent with the practice. The research provides a reference for radiator simulation method and vehicle level finite element simulation model simplification.

Key words: Automobile radiator; Finite element method; Modal frequency and formation

摘要： 汽车散热器是整车热管理的重要零部件之一，其在汽车行驶过程中极易发生共振与噪 音，进而可能导致发生泄漏等失效，在设计阶段对其进行模态分析可以避免发生此问题。采 用三种方法构建了换热器有限元模型，对其进行了模态分析，三种方法一阶模态频率分别为 80.89 Hz、82.116 Hz 以及 108.94 Hz，并对比了一阶模态频率接近的两种方法的阵型差异，最 终确定出求解精度较高的两种方法。基于这两种方法对散热器在实际工况时的前三阶模态频 率进行求解，发现模态频率有所降低，符合实际。研究为散热器仿真方法与整车级有限元仿 真模型简化问题提供了参考依据。

关键词: 汽车散热器；有限元法；模态频率与阵型