摘要
针对某前置前驱SUV车型歧管式催化器载体破裂消失的问题,同时拟将该车型从国四排放标准升级为国五排放标准并将排气背压降低7kPa,对原排气系统进行优化设计.建立歧管式催化器和整个排气系统CFD模型对流场进行数值模拟,通过改变歧管走向和扩张腔结构,使优化后歧管式催化器平均速度均匀性系数从60.8%提高至86.7%,整体排气背压降低了8.3kPa.使用基于大涡模拟的直接计算声学模型对排气系统气动噪声进行预测,仿真结果显示在关键部位优化方案在低频范围内气动噪声有增大,而在中高频气动噪声减小.
In view of the substrate breakdown problem of manifold catalyst exhaust system for a front precursor SUV,the redesign and optimization of the original exhaust system was carried out to update the emission regulation of this vehicle from stageⅣto stageⅤand to decrease the exhaust system backpressure 7 kPa.The CFD model of manifold catalyst and the whole exhaust system was established to simulate the flow field.The average velocity uniformity coefficient of the redesigned exhaust system increased from 60.8%to 86.7%,and the backpressure of overall exhaust decreased 8.3 kPa after optimizing.The computational aeroacoustics model base on large eddy simulation was used to predict the aerodynamic noise of exhaust system.The simulation results show that the aerodynamic noise of optimization model is increased in low-frequency range but decreased in mid-high frequency range.
作者
卢炽华
冯展
刘志恩
吴海涛
LU Chihua;FENG Zhan;LIU Zhien;WU Haitao(Hubei Key Laboratory of Advanced Technology for Automotive Components,Wuhan University of Technology,Wuhan 430070,China;Hubei Collaborative Innovation Center for Automotive Components Technology,Wuhan University of Technology,Wuhan 430070,China;Elite Power Technology Co.LTD.,Wuhan 430074,China)
出处
《武汉理工大学学报（交通科学与工程版）》
2018年第2期185-189,共5页
Journal of Wuhan University of Technology（Transportation Science & Engineering）
基金
国家重点研发计划项目(2016YFD0700704B)
中央高校基本科研业务费专项资金项目(2017II31GX)资助
关键词
数值模拟
载体破裂
排气系统
优化设计
气动噪声
numerical simulation
substrate breakdown
exhaust system
optimal design
aerodynamic noise
作者简介
卢炽华(1969—):男,博士,教授,主要研究领域为汽车振动与噪声控制技术。
