中文摘要：

利用混合多相流空穴模型对垂直多孔喷油嘴完全发展了的空穴流动进行了三维数值模拟，分析了不同的喷油嘴压力室结构、喷油嘴喷孔入口圆角半径和喷孔倾斜角等对喷油嘴内部空穴流动的影响，为喷油嘴结构优化设计提供了指导：改进型（IMPROVED）喷油嘴综合特性优于标准型（STD）和无压力室型（VCO）喷油嘴；喷孔人口锐边过渡使喷孔空穴层基本均可延伸至喷孔出口，形成“超空穴”现象，加速液流紊乱，可提高雾化质量。

英文摘要：

The numerical simulation of cavitating flow developed fully in nozzle holes of a vertical multi-hole injector with mixture muhi-phase cavitating flow model was carried out. And then the effects of sac geometry, turning angle of the orifice and hole inclination angle on the cavitating flow in nozzle holes were studied. It is finally concluded that the performance of IMPROVED nozzle is better than that of the STD nozzle and the VCO nozzle and small inlet turning angle of the orifice can enhance the atomization of the spray.