汽车排气消声器内部流场及温度场的数值计算  

Numerical simulation of the flow and temperature fields in an automotive exhaust muffler

作　　者：李以农[1] 路明[1] 郑蕾[1] 陈清平 郑玲[1] 

机构地区：[1]重庆大学机械传动国家重点实验室,重庆400030 [2]成都陵川工业有限责任公司,四川成都610110

出　　处：《重庆大学学报（自然科学版）》2008年第10期1094-1097,1102,共5页Journal of Chongqing University

基　　金：国家自然科学基金资助项目(50775225);重庆市自然科学基金重点资助项目(CSTC,2008BA6025)

摘　　要：通过对一典型结构汽车排气消声器进行建模,根据流场计算特点划分网格,利用AN-SYS CFX软件对其内部流场及温度场进行数值模拟研究,分析气流速度、温度变化及压力分布对消声器性能(声学性能和空气动力性能)的影响。分析得出结论,设计消声器时必须考虑从结构上消除产生高速湍流和高速气流的可能,且在满足消声性能的前提下尽量减少压力损失,减少穿孔结构能有效地降低压力损失。By building a model of a typical exhaust muffler structure, a grid mesh was formed based on the calculation characteristic of the flow field. The software ANSYS CFX then was used to numerically simulate the flow and temperature fields in a muffler. The effects of the gas velocity and temperature variation on sound elimination performance, including the acoustics and aerodynamics performance, were analyzed. The result suggests that high-velocity turbulence and high-speed flow should be eliminated from muffler structures when designed. At the same time, to provide satisfactory noise elimination, pressure loss should be reduced as far as possible. The pressure loss can be decreased when reducing the perforation structure.

关 键 词：消声器 流场 温度场 双方程 

分 类 号：TK402[动力工程及工程热物理—动力机械及工程]