带阀消声器阀体开度变化的声学特性分析及应用  

Acoustic Performance Analysis of the Varying Valve Opening Angle for the Muffler with Valve and Its Application

作　　者：刘海涛[1] 郑四发[1] 但佳壁[1] 连小珉[1] 

机构地区：[1]清华大学汽车安全与节能国家重点实验室,北京100084

出　　处：《机械工程学报》2015年第6期135-141,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(51275262)

摘　　要：低频阶次噪声对排气噪声声品质有着重要的影响,带阀消声器成为消除排气低频噪声的手段之一。对带阀消声器进行试验分析和三维数值仿真,发现随着阀体开度的增加,共振器的共振频率向高频移动。进一步从实际带阀消声器结构中提取出一种可调声质量抗共振器子结构单元,采用三维数值方法和集总阻抗传递矩阵模型计算出不同开度下的阀体结构的声质量抗,建立共振器的集总阻抗模型。结果显示,阀体开度变化改变了共振器的声质量抗,而声质量抗是影响共振频率的关键因素,揭示出带阀消声器消除低频阶次噪声的机理。将带阀消声器和对比消声器进行实车测试。结果表明,带阀消声器起到跟踪消减低频阶次噪声的作用。The order noise in low-frequency band has great impact on the sound quality of exhaust noise. The muffler with valve becomes one of the means to eliminate low-frequency noise. The actual muffler with valve is analyzed by experiment and three-dimensional numerical simulation methods. It is found that the resonance frequency shift towards high frequency as the valve’s opening degrees increase. Further, a sub structural unit, named adjustable lumped inertance resonator（ALIR）, is extracted from the actual muffler with valve. Three-dimensional numerical simulation and an in-line lumped element model are used to calculate the lumped inertance of the valve structure with different opening angles. The lumped model of ALIR is established. The results show that the lumped inertance, which changes with the valve’s opening degrees, is the key factor on the shifting of resonance frequency. Therefore the low frequency silencer mechanism of the muffler with valve is successfully revealed. At last, actual vehicle test is implemented with the muffler with valve and a contrast muffler. It is found that the muffler with valve can effectively eliminate the order noise tracing the engine speed times.

关 键 词：排气阶次噪声 声质量抗 共振器 阀体结构 

分 类 号：TB535[理学—物理]