尾气净化消声装置结构设计与性能分析

Structure Design and Performance Analysis of Exhaust Purification Silencers

基于结构形状和尺寸限制,考虑消声特性、阻力损失和载体端面速度均匀性等性能指标要求,设计一款柴油机尾气净化消声装置,使用声学有限元法和有限体积法计算该装置的传递损失和内部流场,分析腔体长度、进出口管穿孔率以及导流环对声学性能与流动特性的影响。基于计算分析,对结构进行优化,经优化设计的尾气净化消声装置能够满足不同频段下的消声需要和不同转速下的阻力损失要求,且载体内气体流动均匀性良好。

Considering the limitation in structure geometry and dimensions and the requirement of silenceperformance, noise attenuation, flow resistance loss and the velocity homogeneity in the end of the silencer, a new type ofdiesel engine exhaust purification silencers is designed. The acoustic finite element method and finite volume method areemployed to calculate the transmission loss and internal flow field of the silencer. The influences of the length of chamber,the porosities of inlet and outlet tubes as well as the guiding annuluses on the acoustic attenuation and flow resistancecharacteristics are analyzed. Finally, the structure is optimized. The numerical results show that the optimized silencer canmeet the requirement of noise attenuation, flow resistance loss and air- flow homogeneity in the silencer under differentspeed conditions.