汽车发动机GDI喷油器喷孔流动特性的研究  

Study on Hole Flow Characteristics in GDI Injector of Automobile Engine

作　　者：朱希[1] 张振东[1] 郭辉[2] 尹丛勃[1] 

机构地区：[1]上海理工大学机械工程学院,上海200093 [2]上海工程技术大学汽车工程学院,上海201620

出　　处：《计算机仿真》2013年第11期125-130,共6页Computer Simulation

基　　金：国家自然科学基金资助项目(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(JWCXSL1201)

摘　　要：研究喷孔内燃油流动特性与喷孔结构布置、工作条件之间的内在规律。为了给GDI喷油器喷孔结构与布置优化提供理论依据,提高缸内燃油喷雾雾化质量,本文采用湍流时均流的雷诺方法,对某型GDI多孔喷油器喷孔内部燃油流动过程进行了变参数数值模拟研究。结果表明:喷孔倾斜角增大,燃油蒸汽体积增大,喷孔流量减小;喷孔长度增加,发生气穴的区域随之加长,但其流速和流量变化不显著;喷孔直径增大,发生气穴的区域减小,喷孔流速降低,流量增大;进口压力增大,发生气穴的区域变大;出口压力增大则对气穴形成具有抑制作用。经实验验证的仿真结果对GDI多孔喷油器结构设计、优化以及直喷发动机燃油供给系统与燃烧室的匹配也具有参考价值。The interior fuel flow characteristics in the GDI injector＇ s hole are an important factor affecting the fuel atomization. In order to obtain the effects of different holes structure and the working pressure on the flow characteris- tics, a GDI injector was chosen as the object and variable parameter simulation of the injector internal fuel flow process has been conducted with the help of RANS. Furthermore, the effects of the hole inclination, aspect ratio, as well as inlet and outlet pressure on flow rate and cavitation have been analyzed in detail. The results show that the flow characteristics of holes are directly related to the structure and arrangement of the holes and working condition. With the increasing of angle inclination of the hole, the fuel vapor volume will enlarge and the outlet flow will de- crease ; the increasing of the length of the injection hole will lengthen the cavitation area, but the velocity and flow rate change in the hole are not significant; with the hole diameter increasing, the cavitation area decreases, and the outlet flow rate is reduced; with the inlet pressure increasing, the cavitation area is significantly enlarged; with the outlet pressure increasing, the cavitation area is obviously inhibited.

关 键 词：直喷喷油器 喷孔结构 气穴模型 流动特性 

分 类 号：TB24[一般工业技术—工程设计测绘]