第35卷(2013)第5期性能与排放
柴油机 Diesel Engine
基于Fluent的排气火花熄灭消声器
性能仿真分析
徐琛，柏祥华
（海军驻南京地区航天机电系统军事代表室，江苏南京210006）
Vol. 35(2013) No. 5
摘要：为掌握火花熄灭消声器内部流动特性，采用瑞流模型和离散相(DPM)模型对双级膨胀腔消声器内气固两相流动情况进行了数值模拟研究。通过建立的模型和边界条件模拟气体流动，利用双向耦合拉格朗日法追踪颗粒运动轨迹；讨论了不同颗粒粒径、入口颗粒浓度以及不同排气流速对火花熄灭效率和压力损失的影响。数值计算结果表明：随着颗粒粒径、入口颗粒浓度及排气流速的
增加，火花熄灭效率逐渐增大，特别是颗粒粒径和排气流速对火花熄灭效率影响比较明显。关键调：火花熄灭消声器；气固两相流；火花熄灭效率；仿真
中图分类号：TK421*.5
文献标识码：A
文章编号：1001-4357(2013)05-0012-04
PerformanceAnalysis of Exhaust Sparks Muffler
BasedonFluent XuChen,Bai Xianghua
( Naval Deputy Office of Aerospace Mechanical and Electrical System in Nanjing District,
JiangsuNanjing210006)
Abstract: To master the intemal flow characteristics of the exhaust sparks muffler, the standard model and DPM model in Fluent was used to investigate the gas-granule two-phase flowability in the silencer, and to calculate the gas-phase flow as well as to comprehensively analyze gas-phase flow filed with the ex-isting model and boundary conditions. Moreover, the Lagrange method of bidirectional coupling method is used to track particle trajectory. The influence of varied particle diameter, inlet particle concentration, and exhaust velocity on sparks out efficiency and pressure loss are discussed.The simulation results shows that the sparks out efficiency is increased with the increase of particle diameter, inlet particle con-centration and exhaust velocity, and that influence of the particle diameter and exhaust velocity are espe-cially obvious.
Keywords: exhaust sparks muffler; gas-granule two-phase flowability; sparks out efficiency; simulation
0引言
排气噪声是内燃机主要噪声源，安装排气消声器是降低排气噪声的有效措施。火花熄灭消声器是一种安装在内燃机排气管路中，允许排气流通过又能消声，且阻止排气流内的火焰和火花喷出的安全
装置。柴油机排放的废气中含有大量微粒，其微粒排放量高出汽油机30~60倍(1-2)。火花熄灭消声器不仅可以阻止排气火花喷出，对柴油机排气微粒的控制也能起到很好的作用。
本文使用Fluent软件对某类型的火花熄灭消声器内气固两相流场进行数值模拟研究，用煤粉颗粒
收稿日期：2013-01-07；
修回日期：2013-06-21
作害简介：徐案（1981-），男，工程师，主要研究方向为内燃机报动噪声控制，E-mail：playxch@gmailcom。