双层分流对冲穿孔管结构消声特性研究  

Study on the Noise Attenuation Characteristics of Diversion and Hedging for Double-layer Perforated Tube Structures

作　　者：张仁琪 朱从云[1] 丁国芳[1] 黄其柏[2] ZHANG Renqi;ZHU Congyun;DING Guofang;HUANG Qibai(School of Mechanical Science and Engineering,Zhongyuan University of Technology,Zhengzhou 450007,China;School of Mechanical Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]中原工学院机电学院,郑州450007 [2]华中科技大学机械科学与工程学院,武汉430074

出　　处：《噪声与振动控制》2023年第2期248-252,284,共6页Noise and Vibration Control

基　　金：国家自然科学基金资助项目(51705545,15A460041)。

摘　　要：发动机排气系统中的噪声特性为高频、宽频带,以及排气气流作用下产生的再生噪声,传统的消声结构不能有效地解决该噪声问题。因此,提出通过将锥形分流单元与双层穿孔管相结合的消声方法。首先通过一个锥形分流单元对进入消声器的气流进行分流,分流后的气流在第一层穿孔管外腔得到充分的减速,再经过第一层穿孔管进行初次消声,然后通过第二层穿孔管进行二次消声,最后通过第二层穿孔管上的小孔进入到对冲腔,使气流在对冲腔发生对冲,气流在对冲的过程中速度逐渐降低,再生噪声减小消声效果增强。通过对双层穿孔管结构的传递损失进行推导,分析结构参数对消声性能的影响,得到传递损失的影响因素与变化特性,并进行实验验证。实验结果表明:提出的消声方法能够在高频入射声波的情况下维持较高的传递损失和较宽的消声频带。The noise of the exhaust system of the engine has the characteristics of high frequency and wide band,and is the regenerative noise induced by the function of the gas flow in the exhaust system.This noise cannot be eliminated by the conventional noise reduction structure.Therefore,a noise reduction method combining the conical segregation element with the double-layer perforated tube is proposed.First of all,the gas flow which enters the muffler is shunted by a conical segregation element,so that the shunted gas flow is decelerated sufficiently in the external cavity of the first-layer perforated tube and the initial noise reduction is completed.Then,the secondary noise reduction is performed by passing the gas flow through the second-layer perforated tube.Finally,the gas flow enters the hedge cavity through the small holes of the secondlayer perforated tube,which creates a gas-flow hedging so that the speed of the gas flow is gradually reduced and the regenerative noise is reduced and the muffling effect is enhanced.The transmission loss of the double-layer perforated tube structure is formulated,the influence of structural parameters on the muffler performance is analyzed,and the influencing factors and variation characteristics of the transmission loss are obtained.The results are verified by experiments.It is shown that the proposed noise reduction method can maintain higher transmission loss and wider acoustic attenuation band in the case of high frequency incident acoustic waves.

关 键 词：声学 消声器 双层穿孔管 分流对冲 传递损失 结构参数 

分 类 号：TK421.6[动力工程及工程热物理—动力机械及工程] TB53[理学—物理]