汽油机可变滚流进气系统瞬态模拟研究  

Transient simulation of the variable tumble intake system for gasoline engine

作　　者：张晓彬[1] 张振东[1] 尹丛勃[1] ZHANG Xiaobin;ZHANG Zhendong;YIN Congbo(School of Mechanical Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学机械工程学院,上海200093

出　　处：《能源研究与信息》2020年第1期46-56,共11页Energy Research and Information

基　　金：国家自然科学基金资助项目(51275309)。

摘　　要：运用动态网格技术对直喷汽油机在不同转速下缸内气体运动进行瞬态模拟研究,分析可变滚流进气系统中滚流调节阀工作状态对进气流动、喷雾及油气混合特性以及缸内燃烧特性的影响。模拟结果显示,滚流阀开启和关闭对缸内燃油分布有着显著的影响。通过关闭滚流阀提高滚流强度,可加快缸内燃油雾化速度,有助于点火时刻在缸内形成浓度均匀的混合气并提高燃烧效率;在低转速下关闭滚流阀,增加缸内滚流比,可以显著提高缸内燃烧压力,增加点火时刻的湍动能,配合较晚的点火时刻形成稳定而快速的燃烧。模拟结果有利于分析和评价不同参数对可变滚流直喷汽油机混合气形成及燃烧特性的影响规律,为可变滚流进气系统的整机开发提供理论依据。The transient simulation of the gas movement in the cylinder of direct injection gasoline engine at different speeds was conducted using dynamic mesh technology in this paper.Furthermore,the influence of working state of tumble regulating valve in the variable tumble intake system on intake flow,spray,fuel-air mixture and combustion characteristics within the cylinder were analyzed.Simulation results showed that the opening and closing of tumble valve had a significant effect on the distribution of fuel in the cylinder.Increasing tumble intensity by closing the tumble valve could enhance the speed of fuel atomization,which was conductive to form mixed gas with uniform concentration and improved the combustion efficiency at the ignition time.At low revolving speed,closing tumble valve could increase the tumble ratio,which significantly increased the combustion pressure in the cylinder.Meantime,the turbulence kinetic energy at the ignition time increased.A stable and rapid combustion could be achieved accompanied by later ignition.The simulation results were helpful to analyze and evaluate the influence of different parameters on the formation and combustion characteristics of the mixed gas in the variable tumble direct injection gasoline engine.Moreover,it could provide a theoretical basis for the development of the engine with variable tumble intake system.

关 键 词：直喷汽油机 可变滚流进气系统 瞬态模拟 缸内流场 

分 类 号：TK411.3[动力工程及工程热物理—动力机械及工程]