OP2S发动机换气系统的扫气口结构优化  

Optimization of Scavenging Port Structure of OP2S Engine Ventilation System

作　　者：李宇鹏 巴鹏[1] LI Yu-peng;BA Peng(School of Mechanical Engineering,Shenyang Ligong University,Shenyang 110159,China)

机构地区：[1]沈阳理工大学机械工程学院,辽宁沈阳110159

出　　处：《机械工程与自动化》2024年第4期42-44,共3页Mechanical Engineering & Automation

摘　　要：对置活塞二冲程发动机是一种取消了配气机构和气缸盖的发动机,其换气过程是影响整机燃烧效率和排放水平的重要因素。应用Fluent建立了OP2S发动机换气部分的CFD仿真模型,研究了在扫气倾角为20°时单层扫气口结构与复合扫气口结构缸内气流流动规律。研究结果表明:单层扫气口结构在换气过程中气缸底部出现明显的速度较低的区域,绕气缸轴靠近轴线的残余废气分布面积较大;复合扫气口结构的扫气气流流经气缸轴线中心及外侧,新鲜气体充入气缸时沿气缸轴线平面内的周向速度分量降低,相对于单层扫气口结构湍动能提高了6.2%,有效降低了残余废气系数,换气效果明显优于单层扫气口结构,提高了扫气效率。The opposed piston two-stroke engine is a kind of engine without valve mechanism and cylinder head.The air exchange process is an important factor affecting the combustion efficiency and emission level of the whole engine.The CFD simulation model of the ventilation part of OP2S engine is established by using Fluent,and the air flow law in the cylinder of single layer scavenging port structure and compound scavenging port structure is studied when the scavenging inclination angle is 20°.The results show that in the single layer scavenging port structure,there is an obvious area with lower velocity at the bottom of the cylinder during air exchange,and the distribution area of residual exhaust gas around the cylinder shaft near the axis is larger.The scavenging air flow of the compound scavenging port structure flows through the center and outside of the cylinder axis,and the circumferential velocity component along the cylinder axis plane decreases when the fresh gas is filled into the cylinder,which is 6.2%higher than the turbulent kinetic energy of the single-layer scavenging port structure.The residual exhaust gas coefficient is effectively reduced,the ventilation effect is obviously better than the single-layer scavenging port structure,and the scavenging efficiency is improved.

关 键 词：对置活塞二冲程发动机 换气过程 扫气口结构 

分 类 号：TP391.99[自动化与计算机技术—计算机应用技术] TK413.62[自动化与计算机技术—计算机科学与技术]