中空挤压铝型材振动声辐射特性

Sound Radiation Characteristics of Extruded Aluminum

随着高速列车车体结构轻量化的发展,中空挤压铝型材结构的车体在高速列车上得到广泛应用,而车体的振动声辐射是高速列车车内噪声的主要来源之一。基于FE-SEA混合法和统计能量分析(SEA)分别建立了高速列车车体铝型材振动声辐射的中频和高频预测模型,计算了在粉红噪声谱激励下和实测轮轨激励下铝型材辐射至半空间的声功率,探索了铝型材几何特征因素和不同速度实测轮轨激励对振动声辐射特性的影响。计算结果表明,在粉红噪声谱激励下,下板对铝型材振动声辐射影响最大,与参考铝型材相比相差大于1 dB。铝型材在实测轮轨激励下,辐射声功率的主要贡献频段为400 Hz^1 600Hz,速度增大加剧了铝型材在400Hz以上中高频频段的振动声辐射。相关计算结果将为高速列车车体铝型材的设计提供理论参考。

Extruded aluminum panel is widely used for weight reduction in high- speed train.However,the sound radiation of the panel is one of the main sources of the interior noise.In this paper,the hybrid FE-SEA model and the SEA model are used to predict the sound radiation of the extruded aluminum under the excitations of pink noise spectrum and wheel-rail excitation spectrum respectively.The influence of different geometry factors of the extruded aluminum and train speeds on sound and vibration is investigated.The results show that when the extruded aluminum is excited by pink noise spectrum,the bottom plates have the greatest impact on the sound radiation.The difference of the sound radiation in comparison with the referenced section aluminum is more than 1 dB.When the extruded aluminum is excited by wheel-rail excitation spectrum,the main frequency of sound radiation ranges from 400 Hz to 1 600 Hz.The results may provide a theoretical guidance for the design of the extruded aluminum.