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

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