摘要
分段喷射在直喷发动机中获得了广泛的应用,但在闪沸工况下研究较少.该研究采用米氏散射高速摄影法获取分段喷射闪沸喷雾宏观形态,采用光流法估算喷雾速度,综合分析了分段喷射闪沸喷雾的宏观特性.研究发现,相较于单次喷射,在相同喷油量下分段喷射闪沸喷雾能够有效降低喷雾总贯穿距;由于残留流场,分段喷射的第2段喷雾运动会受到第1段喷雾的影响,贯穿更快.该影响主要与喷射间隔时间和闪沸程度相关,时间间隔越大、闪沸程度越低,影响越小.
Split injection has been widely used in direct injection engines,but the studies related to flash-boiling conditions are very limited.Through capturing the Mie scattering high-speed images of flash-boiling spray with split injection and estimating the spray velocity by the optical flow algorithm,this study comprehensively analyzed the macroscopic characteristics of flash-boiling spray with split injection.It was found that,compared to the single injection,the split injection under flash-boiling regime can effectively reduce the total spray tip penetration.Due to the residual flow field,the spray from the second injection was affected by the first injection,with faster penetration.The impact was mainly related to injection interval time and flash-boiling intensity,and a larger time interval and a lower flash-boiling intensity usually led to smaller impact.
作者
徐青林
孙哲
李雪松
许敏
Xu Qinglin;Sun Zhe;Li Xuesong;Xu Min(School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《燃烧科学与技术》
EI
CAS
CSCD
北大核心
2021年第3期249-254,共6页
Journal of Combustion Science and Technology
基金
国家自然科学基金资助项目(52006140).
关键词
分段喷雾
闪沸
直喷
喷雾
光流法
split injection
flash boiling
direct injection
spray
optical flow
