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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),630Hz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1 600 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 aluminum profile body with viscoelastic damping layer applied to the high-speed train car body, the sound insulation and vibrational sound radiation calculation model of aluminum profile for high-speed train body is established. Mixed FEA - Statistical Energy Analysis (FE-SEA), Statistical Energy Analysis (SEA) for high frequencies above 630 Hz. Based on the test data, the Young’s modulus and damping loss factor of the viscoelastic material are considered. Based on the numerical model, the influence of temperature on the sound insulation and vibrational sound radiation of aluminum profile under different temperatures was studied. The influence of temperature on the acoustic performance of the aluminum profile with damping layer was analyzed. The results show that the influence of temperature mainly lies in the resonance zone and the high frequency band above 1 600 Hz. When the damping layer is in the environment of 10 ℃ ~ 50 ℃, the acoustic performance of the aluminum profile is better when it is in the viscous flow state. However, the damping effect of the damping layer laid on the environment below 10 ℃ will be weakened.