【作者】 麻建省；

【导师】 赵亮； 王国顺；

【作者基本信息】 大连交通大学 ， 机械电子工程， 2008， 硕士

【摘要】 随着铁路客车的不断提速,车厢内的噪声也随之增加,而实践证明车厢内的噪声还没有达到所规定的指标,车厢内部噪声问题凸显出来。本论文以铁路客车车厢结构为载体,应用统计能量的理论和方法,通过数值仿真,实现对轨道车辆车厢的声学和结构动力学建模,预测车体内场的声学环境。本文首先在综述大量相关文献的基础上,系统总结了统计能量分析法的发展简史和研究现状。并在此基础上,研究了统计能量分析的基本假设和适用范围,二子系统和多重子系统的统计能量分析模型的建立以及对一个系统进行统计能量分析的一般步骤。其次讨论了有关噪声方面的知识和噪声的定义,以及一些在振动噪声仿真预测中常用的名词术语,应用这些知识简单阐述了噪声的分类以及其对环境和人类造成的危害,同时也对噪声的评价以及噪声控制的一般方法进行了探讨。再次以加筋板为例,研究了通过改变筋板的形式和位置,实现降低结构噪声辐射的目的。加筋薄板是在工程实际中经常用到的一种减振降噪的结构形式。本文对加筋板结构的振动和声辐射特性进行了研究,在统计能量分析原理的基础上对薄板在何位置加筋以及何种几何形状的筋的减振降噪效果进行了深入研究,定性的得出以激励通过加筋位置、槽形截面筋板的综合性能指标能较好地符合工程上的需要。最后建立车体的振动噪声仿真模型,在此基础上对车体模型进行仿真预测,得出了车体内部的噪声级,影响车体噪声的主要传播路径,同时应用上面所研究的结果,将模型采用加筋板的形式再进行预测仿真计算,与原模型进行对比,得出采用加筋板形式可以有效地降低车体的结构噪声。最后提及了一些具体的如增加板厚度和选择阻尼损耗因子较大的阻尼材料等内场降低噪声的控制措施。更多还原

【Abstract】 With increase of speed of the train passenger, the noise of the interior of the track vehicles is increasing, too. This paper chose the compartment as platform, use statistical energy theory and method, simulate compartment’s acoustics and structural dynamics model and forecast the interior acoustic environment of compartment.Firstly, a systematic study of lots of paper is made,developing history and recent status home and abroad of statistical energy analysis are introduced. The study of fundamental assumption, application scope and model of two-subsystem and multiple-subsystem of statistical energy analysis are made. Then general procedure of statistical energy analysis is introduced.Secondly, the knowledge about noise is introduced, simply introduce the definition of the noise, and the terminologies about the noise in the reducing vibration and noise, discuss the category and harm for the environment and human of the noise with these knowledge. At the same time, introduce the noise assessment and the generic way of noise control.Thirdly, analyze the way of reducing noise, and choose the stiffened plate to study to achieve reducing noise. The stiffened plate is the better way in the reducing noise based on the statistical energy analysis in the engineering object. Here the study of the stiffened plate is made, and study the position of the stiffeners and the geometrical shape of the stiffeners in the plate which is better in the reducing the vibration and noise. The result is the position which the excitation must through the stiffener is better, and the trough stiffener having better effect under the synthesized target.Finally, the model of the track vehicles` bodywork structure is established, and then based on the model simulate and predict the noise level of the interior of the track vehicles, obtain the noise level of the model and the way to affect the interior noise of the track vehicles. At the same time apply the previous result——about the position and the geometry shape of the stiffeners in the model that established, then simulate and predict, compare the result with the former,know that the stiffened plate can efficiently reduce the noise level of the track vehicles. At last some measurement to reduce the noise is suggested,such as increasing plates’thickness and choosing material with large damping loss factor.更多还原