GDI发动机喷雾特性的数值模拟和试验  

Numerical Simulation and Experiment on Spray Characteristics of GDI Engines

作　　者：李波[1] 李云清[2] 王德福[2] 

机构地区：[1]中国汽车技术研究中心,天津300162 [2]北京航空航天大学交通科学与工程学院,北京100191

出　　处：《内燃机学报》2012年第1期9-15,共7页Transactions of Csice

基　　金：国家自然科学基金资助项目(50376003)

摘　　要：汽油直喷发动机高压燃油喷射系统与燃油经济性和废气排放等密切相关,通过试验和数值模拟对高压喷油系统和旋流喷油器的喷雾特性进行了研究.在不同喷射压力、背压压力条件下,利用高速摄像机对喷入定体积容器的喷雾进行了喷雾贯穿距离和喷雾锥角参数的测量.结果表明:在低背压压力下,喷雾呈现出空锥、较大范围的分布形态,有利于实现燃油与空气的均质混合;在高背压条件下,喷雾呈现出紧凑密集的分布形态,有利于实现燃油与空气的分层混合.获得的贯穿距离经验公式与试验测量值在一定范围内是一致的.基于AVL HYDSIM环境建立了一维高压喷油系统模型,模拟得到的针阀升程与试验获得的图像在时间上具有一致性.Spray characteristics of high-pressure swirl type of gasoline direct injection（GDI）injector are investigated experimentally and numerically.Visualized experiment was carried out in a constant volume chamber using high speed CMOS camera.Spray penetration,spray cone angle,spray tip velocity and droplet characteristics were measured at different injection pressures and injection durations as well as different ambient pressures.Results show that at low ambient pressure,the spray shows a hollow cone pattern with wide spray angle which is beneficial to the preparation of homogenous mixture,while the spray exhibits a solid compact cone pattern at high ambient pressure which produces the stratified mixture.The correlated empirical equation for spray penetration is validated by the experimental results.Numerical analysis was made based on one-dimensional model in the AVL HYDSIM environment.Consistency in needle lift is found between the model prediction and measured.

关 键 词：汽油直喷发动机 高压燃油喷射系统 喷雾特性 数值模拟 

分 类 号：TK412[动力工程及工程热物理—动力机械及工程]