GDI多孔喷油器喷雾特性的试验与仿真研究  

Numerical Simulation and Experimental Study for Spray Characteristics of the Gasoline Direct Injection(GDI)Multi-Hole Injector

作　　者：朱希[1] 张振东[1] 程强[1] 

机构地区：[1]上海理工大学机械工程学院,上海200093

出　　处：《内燃机工程》2015年第6期137-143,共7页Chinese Internal Combustion Engine Engineering

基　　金：国家自然科学基金项目(51275309);上海市教委科研创新项目(13YZ110);上海理工大学研究生创新基金项目(JWCXSL1201)

摘　　要：利用工程分析软件AVL FIRE在不同进出口压力、燃烧室温度、长径比及喷孔倾角等变量条件下,对GDI喷油器流量特性、雾化形态、贯穿距离及雾化颗粒进行仿真分析,并采用高速摄影技术对仿真结果进行验证。研究结果表明:仿真与试验结果相吻合;随着喷射压力增大,雾束的贯穿距增大,雾化效果显著提高;燃烧室压力增大会使喷雾雾化粒径减小;燃烧室温度提高可使喷雾液滴蒸发加快,有利于混合气的形成;较小的喷孔直径使得孔内流速较高,雾化效果更理想;喷孔长度变化对喷雾的影响并不显著;喷孔倾角增大,喷雾粒径也相应增大。By using the software AVL FIRE, a variable parameter simulation analysis about GDI injector＇s flow characteristic, atomization pattern, penetration distance and particle size under different conditions such as inlet and outlet injection pressure, combustion chamber temperature, aspect ratio, as well as injection hole inclination was put forward, which was verified by the high-speed photography technology. The results show that the simulated data were very consistent with the experimental results. As the injection pressure increased, the penetration distance enlargd and atomization effect enhanced significantly. Increasing the combustion chamber pressure would cause the fuel particle size small; and increasing the combustion chamber temperature would makd the fuel, droplet evaporation speed up which is beneficial to the fuel/air mixture formation. The smaller injection hole diameter increased, the flow velocity, and resulted in the better atomization. The length of injection hole had no significant effect on the atomization. As the inclination angle of injection hole increased, the fuel particle size also increased.

关 键 词：内燃机 GDI多孔喷油器 喷孔结构 流动特性 喷雾形态 数值模拟 

分 类 号：TK421.5[动力工程及工程热物理—动力机械及工程]