利用混合FE-SEA方法的前围隔声性能优化设计*

为了提升某重型商用车前围的隔声性能,建立了用于分析前围传递损失的有限元-统计能量分析(FE-SEA)模型。针对前围结构复杂的特点,依据FE-SEA模型建模原则,提出了通过在表面创建声腔来确保能量在模型中的正确传递路径。将仿真结果与测试值对比,二者误差小于1.6 dB(A),验证了FE-SEA方法的准确性。用吸声材料与隔声材料复合设计前围声学包,采用正交试验法对前围声学包进行优化设计并对各个试验方案进行仿真计算。对仿真结果进行极差分析与方差分析,选出了在传递损失、重量和厚度三方面达到最佳平衡的声学包:毛毡(10 mm)+EPDM隔声垫(2 mm)。结果表明,优化后的前围传递损失在测试频率315 Hz～2000 Hz范围内最小提升了3.8 dB(A),最大提升了7 dB(A),前围的隔声性能得到较大的提升。

Optimization design of sound insulation property in front wall using hybrid FE-SEA method

In order to improve the sound insulation performance of the front wall of a heavy commercial vehicle, a FE-SEA model was developed to analyze the front wall transmission loss. In view of the complex characteristics of the front wall structure, according to the FE-SEA model modeling principle, a method of ensuring the correct transmission path of energy in the model by creating acoustic cavity on the surface is proposed. The simulation results are compared with the test values, the error is less than 1.6dB (A), which verifies the accuracy of the FE-SEA method. The acoustic package is designed by using the sound absorbing material and the sound insulation material. The acoustical packet of the front wall is optimized by the orthogonal test method and the simulation analysis is carried out. Based on the range analysis and ANOVA of the simulation results, the acoustic package which achieves the best balance in transmission loss, weight and thickness is selected: Felt (10mm) + EPDM sound barrier mat (2mm). The transmission loss of the front wall, after optimization, in the test frequency of 315Hz ~ 2000Hz the minimum increase of 3.8 dB (A), the maximum increase of 7 dB (A). The sound insulation performance of the front wall is greatly improved.