椭圆截面扩张式消声器消声特性的有限元分析(续1)

FEA on Attenuation Performance of Expansion Chamber Mufflers with Elliptical Cross Section(Continued1)

为提高消声器的消声性能,文章采用有限元法对具有椭圆截面的简单扩张消声器进行了消声特性分析。阐述了椭圆截面与圆形截面消声器的性能差异和结构参数对消声性能的影响;计算了改进内插管、出口管偏置及多级扩张室结构对椭圆截面扩张室式消声器消声性能的影响。结果表明,椭圆截面的消声器性能略差,除了扩张比和扩张室长度外,椭圆截面的离心率对消声性能有重要影响;采取内插管、出口管偏置和多级扩张室等结构能有效克服该类型消声器的缺点。

The finite element method is used to analyze the attenuation performance of expansion chamber mufflers with elliptical crnss section in order to improve attenuation performance of muffler in this paper. The paper introduces the effect caused by performance difference and structure parameter of elliptical cruss section and circular cross section, calculates the effects on muffler performance made by inner tube, offset of outlet tube and the structure of expansion room. The results show that,the performance of muffler with elliptical cross section is poorer and besides the expansion ratio and the length of expansion chamber,the eccentricity has an important effect on the attenuation performance. By adopting the structures of inner tube, offset of outlet tube and multi-level expansion room, the drawbacks of muffler can be overcome.