为了研究温度变化对敷有黏弹性阻尼层的高速列车车体铝型材结构声学性能的影响,建立高速列车车体铝型材隔声和振动声辐射计算模型,其中100 Hz~500 Hz中低频段采用混合有限元-统计能量分析法(FE-SEA),630 Hz以上高频段采用统计能量分析法(SEA).基于试验测试数据,考虑黏弹性材料温变特性对其杨氏模量和阻尼损耗因子的影响.通过数值模型,研究不同温度条件下铝型材隔声量及振动声辐射性能的变化,分析温度对敷有阻尼层的铝型材声学性能的影响.结果显示:温度的影响主要集中在共振区及1600 Hz以上的高频段.阻尼层在10℃~50℃环境中,即处于黏流态时对铝型材声学性能的优化作用较好,但在10℃以下环境中敷设阻尼层的降噪效果将有所减弱.%In order to study the influence of temperature on the acoustic performance of extruded aluminum structures with viscoelastic damping layers of the car-bodies of high-speed trains, the models for sound transmission loss prediction and sound radiation characteristics prediction are established respectively. The acoustic performances of the models are analyzed using the hybrid FE-SEA within the low and medium frequency range of 100 Hz-500 Hz and using the SEA in the high frequency range above 630 Hz respectively. Based on the measurement data, the influence of temperature-varying characteristics of the viscoelastic material on its Young's modulus and damping loss factor is analyzed. The sound transmission loss and sound radiation characteristics of the extruded aluminum under different temperatures are calculated using the numerical models. The influence of the temperature on the acoustic performance of the extruded aluminum with damping layers is investigated. The results show that the influence of the temperature is focused on the resonance frequency region and the high frequency region above 1600 Hz. The viscoelastic damping layer has a great noise control effect in the temperature range of 10℃-50℃, but will lose its effect for noise reduction below 10℃.
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