【作者】 王耀前；

【导师】 陆森林；

【作者基本信息】 江苏大学 ， 车辆工程， 2003， 硕士

【摘要】 汽车工业发展迅速，使得汽车噪声污染日益严重。减小排气噪声是降低汽车噪声的关键，目前在排气系统中安装排气消声器是减少排气噪声的主要方法。因此准确计算和预估排气消声器的性能具有很重要的意义，本文在此方面做了一些研究。 本文讨论了运用ANSYS分析软件对抗性消声器性能进行三维有限元计算的方法，建立了消声器内部声学有限元方程的数学模型，推导了消声器插入损失和传递损失的计算公式。在此基础上使用精度较高的声学单元FLUID30和FLUID130作为建模单元，在静态条件下建立了两种类型消声器的有限元模型。利用声传递矩阵的理论对两种类型消声器进行了直接模拟和间接模拟，计算出了消声器的四端网络参数、插入损失和传递损失。计算结果和试验结果进行比较，取得了比较一致的良好效果。从而表明ANSYS有限元分析软件计算消声器声学性能可行方便。 本文的研究内容，概括了消声器理论、有限元理论与计算、ANSYS软件应用、双传声随机激励技术等。并且对许多关键性问题，如有限元单元网格的划分、有限元模型的建立、软件后处理的数据分析技巧与注意事项等都进行了探讨。因此本文对以后消声器的性能预测、计算提供了重要的理论参考和工程实例。更多还原

【Abstract】 Automobile industry has been developing very fast. And at the same time, automobile noise pollution has been severer than before. The reduction of exhaust system noise is the key to the reduction of automobile noise. At present, the main method to reduce exhaust noise is by setting muffler in automobile exhaust system. So calculating and predicting the performance of the muffler is of great significance and the work of this thesis is a practice in this aspect.With the FE software ANSYS, the performance of reactive muffler is calculated by the 3-D FEM (Finite Element method) in this thesis. The mathematical model of inner acoustic FE equation is established and the calculation formulas about TL (transmission loss) and IL (insertion loss) of muffler are deduced. On this basis, with highly-precise acoustic elements FLUID30 and FLUID 130, the FE model of two kinds of mufflers are developed under static state working condition. By means of acoustic transmission matrix, the muffler is being simulated directly and indirectly. The foul-terminal network parameter, TL and IL are calculated, too. In the end, through comparing simulation results and experiment results, it shows that calculated values coincide well with measured values. The simulation method is proved to be correct and calculation of acoustic performance of muffler by ANSYS FE analysis software is also proved to be practical and expedient.Muffler theory, FEM theory, ANSYS application, double-propagation haphazard stimulation technology are included in this thesis. Some key factors such as FE mesh demarcation, establishment of FEM model and post-processor of ANSYS are also discussed in this thesis. So, important theory and project example of the performance of muffler prediction are provided by this thesis.更多还原