橡胶层与空腔的结构-声耦合解析模型和隔声优化

Structural-acoustic Coupling Analytical Model and Sound Insulation Optimization of Rubber Layers and Cavity

摘要:

针对橡胶薄层与空腔的声学耦合，提出一种结构?声耦合解析模型，并基于该模型对密封条的材料与几何参数进行优化。通过加入余弦辅助函数，得到空腔的声学模态振型函数。利用瑞利?里兹法，建立简支双薄层结构振动与空腔声学耦合的解析模型。利用该模型分别计算单点激励的均方响应和扩散声场激励的隔声。通过与阻抗?迁移率方法和混合有限元?统计能量分析（FE?SEA）方法的计算结果对比，验证了该解析模型的准确性。结果表明：与FE?SEA方法相比，该解析模型具有较高的计算效率；利用该解析模型和粒子群算法优化材料与几何参数，使得隔声提高10 dB以上；优化的密封条趋向于扁而宽的截面。

关键词:汽车门密封条;结构‒声耦合;解析模型;扩散声场;隔声优化

Abstract:

In view of the acoustic coupling between rubber thin layers and a cavity， an analytical model for structural-acoustic coupling was proposed， and the material and geometric parameters of sealing strip were optimized based on the model. The acoustic modal shape function of the cavity was obtained by adding an auxiliary cosine function. By employing the Rayleigh-Ritz method， the analytical model was established for the structural-acoustic coupling between the vibrations of simply-supported layers and the coupled cavity. The analytical model was used to calculate the mean square responses of a double-wall model under single-point force and the sound transmission loss under a diffuse acoustic field， respectively. The accuracy of the model was verified by comparing with the results of the impedance-mobility method and the numerical method of hybrid finite element-statistical energy analysis （FE-SEA）. The results show that： the proposed method has higher computational efficiency than the FE-SEA method； the analytical model and particle swarm algorithm can optimize the material and geometric parameters so that the sound insulation can be improved by more than 10 dB； the optimized sealing strip tends to have a flat and wide cross-section.

Key words:automotive door sealing strip;structural-acoustic coupling;analytical model;diffuse acoustic field;sound insulation optimization