【作者】 饶建渊；

【导师】 陈剑；

【作者基本信息】 合肥工业大学 ， 机械制造及其自动化， 2008， 硕士

【摘要】 发动机排气噪声是车辆噪声的重要组成部分,对车辆NVH性能影响十分明显。本文以某SRV排气系统声学性能分析项目为背景,对该车装配的前后排气消声器以及整个排气系统的声学性能进行计算和分析。本文的主要研究内容如下:1、总结了CAE技术的概念、特点、流程,以及有限元法和边界元法计算声场的基本原理;2、对现有排气系统传递损失、声压级差值的试验测试方法、以及消声器评价指标等进行了总结与比较;3、利用有限元法、边界元法分析计算获得了包括扩张腔、内插管、穿孔管、阻性材料在内的消声器各个消声结构的消声性能,讨论了扩张比,阻性材料密度、插入管深度等相关参数对其声学性能的影响;4、分析计算了温度,气流等因素对消声器传递损失的影响;使计算结果更接近真实值;5、获得某排气消声器与排气系统的传递损失和声压级差值,分析了误差产生的原因,为整车噪声控制提供参考;6、根据以上CAE的分析结果,提出排气系统的噪声分析与控制的方法和措施,为实施降噪方案提供依据。更多还原

【Abstract】 Engine exhaust noise is an important part of vehicle noise. It influences the NVH behavior of the vehicle greatly. In this paper, mainly study focus on a SRV exhaust noise. The acoustic characteristics about exhaust mufflers and exhaust systems are analyzed. The main work is listed as follows.1. the concept, characteristics and process of CAE technology are introduced. And the basic principles of Finite Element Method and Boundary Element Method are presented.2. the noise elimination of silencing structure are calculated respectively.3. the effect of the temperature and airflow on transmission loss is analyzed.4. the calculations of transmission loss of exhaust mufflers and exhaust systems are obtained respectively. And the causes of error are presented.5. the fundamental methods of noise analysis and control of exhaust systems are given. And the acoustic characteristic evaluation standards for the source of exhaust systems, the exhaust muffler and the exhaust system are also listed.更多还原