喷油器安装角对156FMI发动机缸内直喷燃烧过程的影响  

Effect of Injector Mounting Angle on Direct Injection Combustion Process in 156FMI Engine

作　　者：谢冬和 周瑜飞 XIE Donghe;ZHOU Yufei(Hunan Automotive Engineering Vocational University,Zhuzhou,Hunan,412001,China)

机构地区：[1]湖南汽车工程职业大学航空工程学院,湖南株洲412001

出　　处：《小型内燃机与车辆技术》2024年第5期8-16,共9页Small Internal Combustion Engine and Vehicle Technique

基　　金：湖南省自科基金项目(2022JJ60065),基于GDI技术摩托车燃烧性能的研究。

摘　　要：以156FMI摩托车发动机为原型,针对其进气道喷射改为缸内直喷时喷油点位置的确定问题展开研究,考察喷油器安装角对缸内直喷燃烧过程的影响。基于四方程湍流模型、Enable扩散模型、walljet碰壁模型、Dukowicz蒸发模型和KHR破碎模型以及ECFM燃烧模型模拟156FMI摩托车发动机缸内直喷燃烧过程,并充分考虑此发动机缸盖空间位置的限制,将喷油器安装在相对气缸盖原火花塞对称位置,研究喷油器安装角对缸内平均压力、温度、瞬时放热率及压力升高率等的影响。结果表明:循环喷油量10 mg、转速3 600 r/min及当量比为1的工况下,θ为55°时,相较于35°峰值压力增大了19.85%,峰值相位提前了2.5°CA,温度峰值升高了14.89%。θ从40°增大到55°时气缸内的压力、温度、瞬时放热率和累积放热量峰值都不同程度地出现了上升,峰值对应的相位角也出现了不同程度的提前,缩短了着火落后期,使气缸内的混合气燃烧速率加快。当θ为55°时,火焰传播速率最快,气缸内的热功转换效率最高,其在燃烧性能方面较好。研究结果为156FMI摩托车发动机缸内直喷技术的应用提供了理论指导和参考。Taking the 156FMI motorcycle engine as a prototype,this study focuses on the determination of the injection point position when the intake port injection is changed to direct injection in the cylinder,and investigates the influence of injector installation angle on the combustion process of direct injection in the cylinder.Based on the four equation turbulence model,Enable diffusion model,Walljet collision model,Dukowicz evaporation model,KHR fragmentation model,and ECFM combustion model,a direct injection combustion process in the cylinder of a 156FMI motorcycle engine was established.The spatial limitations of the engine cylinder head were fully considered,and the injector was installed symmetrically on the cylinder head relative to the original spark plug on the cylinder head axis.The influence of the injector installation angle on the average pressure,temperature,instantaneous heat release rate,and pressure rise rate in the cylinder was studied.The results showed that under the working conditions of cyclic fuel injection rate of 10 mg,rotational speed of 3 600 r/min,and equivalence ratio of 1,when θ was 55 °,the peak pressure increased by 19.85% compared to 35°,the peak phase advanced by 2.5 °CA,and the temperature peak increased by 14.89%.When θ increased from 40° to 55°,the pressure,temperature,instantaneous heat release rate,and cumulative heat release peak in the cylinder all increased to varying degrees,and the phase angle corresponding to the peak also advanced to varying degrees,shortening the ignition delay and accelerating the combustion rate of the mixture in the cylinder.When θ is 55°,the flame propagation rate is the fastest,and the thermal power conversion efficiency in the cylinder is the highest,indicating good combustion performance.The research results provide theoretical guidance and reference for the application of direct injection technology in 156FMI motorcycle engines.

关 键 词：缸内直喷 燃烧性能 喷油器安装 

分 类 号：U483[交通运输工程—载运工具运用工程]