基于FE-SEA混合法的高速列车车内噪声全频段预测及声学优化设计

The interior noise of high-speed train has been paid more and more attention. The interior noise of high-speed train in low or high frequency ranges respectively under single excitation and passive control measure are researched in the most past studies. However， it is lack that the full-spectrum interior noise of high-speed train under multi-physical-field coupling excitations and active control measure are researched. In this project, the acoustic vibration simulation model of acoustic cavity outside-vehicle body- acoustic cavity inside coupling system under multi-physical-field coupling excitations will be built base on FE-SEA hybrid method. In detail, different modeling units are adopted according to the modal density of each subsystem, that is FEM and SEA are used in low and high frequency ranges respectively. The contradiction between computational efficiency and precision will be solved. The full-spectrum （0-4000Hz） interior noise of high-speed train will be obtained and the accuracy of prediction will be improved.Moreover, the relationship among interior noise, excitation source and noise transmission paths will be analyzed, and the generation mechanism of interior noise at origin will be explored. The sensibility of important parameters to interior noise will be analyzed to presented significant parameters. In addition, the effect of acoustic reduction by optimizing the design of sensitive components and the feasibility of the scheme for vibration and noise reduction will be analyzed to present the optimal controlling method. The successful implementation of this project would provide not only important reference for the design and research of new type trains, but also new method for the prediction of vibration and noise of large-scale comprehensive system. Therefore this project has great signification on economic benefit, science and technology.

高速列车车内噪声问题日益受到关注，已有成果大多针对某部分激励作用下低频段或高频段的车内噪声及被动控制措施进行研究，而耦合物理场作用下的车内噪声全频段及主动控制措施的研究仍需深入。本项目采用FE-SEA混合法，考虑多物理场耦合激励，建立车外声腔-车体-车内声腔耦合系统声振仿真模型，根据子系统模态密度分别选择FEM（有限元法）、SEA（统计能量分析）单元，有效解决计算效率与计算精度的矛盾，对车内噪声全频段（0-4000HZ）进行预测，提高预测精度。在此基础上分析车内噪声空间及频谱特性，探究产生、传播机理，分析车内噪声与系统激励、噪声传递路径、车体结构声学性能等影响因素的相关度，揭示关键参数。进而在源头上有针对性地提出减振降噪的主动控制措施，对车体敏感部件进行有目的地优化设计，将为列车声学设计研发提供参考依据，也将为大型综合声振系统仿真方法提供新思路，具有较大的科学技术意义和经济效益。

高速列车车内噪声问题日益受到关注，已有成果大多针对某部分激励作用下低频段或高频段的车内噪声及被动控制措施进行研究，而耦合物理场作用下的车内噪声全频段及主动控制措施的研究仍需深入。本项目采用FE-SEA混合法建立了车体-车内声腔耦合系统声振仿真模型，根据子系统模态密度分别选择FEM（有限元法）、SEA（统计能量分析）单元，有效解决计算效率与计算精度的矛盾，对车内噪声全频段（0-4000HZ）进行了预测，提高了预测精度。研究分析了列车白车身的内部噪声，二系悬挂力对列车内部噪声在低频段内影响更加显著，并分析了列车结构各部分对车内各声腔的贡献度，得知底板振动对乘客耳部所在声腔的贡献度最大。选用轻质玻璃棉，矿棉及毛毡分析不同吸声材料对车内噪声的控制效果。并分析了不同厚度玻璃棉的降噪影响。以我国的实际高速列车为例，研究了以玻璃棉作为吸声材料的车内噪声降噪效果。将为列车声学设计研发提供参考依据，也将为大型综合声振系统仿真方法提供新思路，具有较大的科学技术意义和经济效益。