铁路客车室内噪声预测与控制技术研究

Research on prediction and control of interior noise in railway passenger-car

为探索铁路客车室内低频噪声预测分析与控制的可行办法,提高车室内噪声品质,本文基于有限元和边界元结合的方法给出了铁路客车结构-声场耦合系统振动分析模型的建模方法;通过对比分析结构振动模态、车室内空腔声学模态以及结构-声场耦合系统模态的相关性,澄清车室内噪声形成机理;对客车结构-声场耦合系统在0 Hz^200Hz频率范围内进行谐响应分析之后,确定了室内噪声观测平面及测试点在不同频率下的声压级,通过对客车车身面板声学贡献度的分析,确定主要噪声源和对内部声场影响较大的面板,为降低噪声而试图对客车结构进行修改提供了理论依据。

In order to improve interior acoustic quality of railway passenger-car, research on prediction and control of low-frequency noise inside the passenger-car is performed based on FEM and BEM. A passenger-car model is set up, giving consideration to structure-acoustic coupling characteristic of the car. The mode analysis and harmonic analysis under 0 Hz-200 Hz for the ear structure model, air cavity model and acoustic-structure coupling model are carried on, respectively. Then, the acoustic field distribution at low frequency inside the car is analyzed, and acoustic contribution coefficient of car-body panel at focused frequencies are studied to identify the main structure-borne noise sources. Hereby the approach in this paper can be used to provide theoretical data for structure acoustic design at low-frequency.