隔板缝隙对抗性消声器声学性能影响的试验研究

摘要

采用试验方法研究隔板缝隙对消声器声学性能的影响,结果表明,隔板缝隙对扩张式消声器影响不大,但将提高共振式消声器共振频率.分析其原因是由于隔板缝隙的存在,增大了等效旁支管的总横截面,因而减小了其声质量,提高了系统的固有频率；而加长隔板翻边的长度,使旁支管的长度变长,声质量增大,共振频率降低,因而可部分抵消缝隙的负面影响.%An experiment study on the effects of baffle seams on the acoustic performance of reactive mufflers is conducted. The results show that baffle seams have little effects on expansion muffler, but it increases the resonance frequency of reactive muffler. Analysis reveals the reason that the baffle seams increase the total area of cross section of equivalent bypass pipe and hence reduce its acoustic mass and raise the natural frequency of the system ; while the increase in the length of baffle flange, makes equivalent bypass pipe longer and hence increases its a-coustic mass and lowers the resonance frequency of muffler. In this way the negative effects of baffle seams can be partly set-off.