初始气泡对柴油机近口区初始射流破碎的影响  

Effect of Initial Bubbles on Initial Fuel Jet Breakup in Near Diesel Nozzle

作　　者：高永强 陶莉莉 王希波[1] 张克松[1] 刘永辉 常静 GAO Yongqiang;TAO Lili;WANG Xibo;ZHANG Kesong;LIU Yonghui;CHANG Jing(School of Automotive Engineering,Shandong Jiaotong University,Jinan 250357,China)

机构地区：[1]山东交通学院汽车工程学院

出　　处：《山东交通学院学报》2019年第3期1-6,共6页Journal of Shandong Jiaotong University

基　　金：山东交通学院博士启动基金资助项目(BS201901047)

摘　　要：为改善柴油机喷油器喷孔内的残留燃油和初始气泡对近口(喷油器燃油喷口)区初始射流形态的影响,基于湍流模拟(large eddy simulation,LES)和界面追踪(volume of fluids,VOF)方法进行燃油近口区初始射流雾化过程的数值模拟,重点研究初始气泡对近口区初始射流形态和破碎过程的影响。结果表明:喷孔内初始气泡的大小和位置对初期射流雾化形态有显著影响,针阀开启后新喷入的燃油撞击初始气泡溃灭产生强烈扰动是造成初始射流头部破碎的主要因素。结合湍动能和亚网格涡黏系数进一步分析初始气泡对近口区初始射流结构形态及破碎的影响规律。In order to improve the influence of residual fuel and initial bubbles in the diesel nozzle on the initial jet pattern,the numerical simulation of the initial jet atomization process in the near fuel nozzle area is carried out based on the methods of the large eddy simulation(LES)and volume of fluids(VOF).The effect of initial bubbles on the initial jet pattern and breakup process of the near nozzle area is studied.The results of numerical simulation show that the size and position of the initial bubbles in the nozzle have a significant effect on the atomization pattern of the initial jet.After opening the needle valve the collapse of the initial bubbles caused by the impact of the newly-injected fuel produces a strong disturbance,which is the main factor crushing the initial jet head.Combined with the turbulent energy and subgrid vortex viscosity coefficient,the influence law of the initial bubbles on the structure pattern and fragmentation of the initial jet in the near nozzle area is further analyzed.

关 键 词：初始气泡 初始射流 破碎机理 LES 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]