喷嘴几何结构对涡线空化特性影响的数值模拟研究  

Numerical Study of Effect of Geometric Parameters on the Characteristics of Vortex Cavitation inside Diesel Injector Nozzles

作　　者：白天阳 郭根苗 管伟 李琛 何志霞 王谦[2] Bai Tianyang;Guo Genmiao;Guan Wei;Li Chen;He Zhixia;Wang Qian(Institute for Energy Research,Jiangsu University,Zhenjiang 212013,China;School of Energy and Power Engineering,Jiangsu University,Zhenjiang 212013,China)

机构地区：[1]江苏大学能源研究院,镇江212013 [2]江苏大学能源与动力工程学院,镇江212013

出　　处：《燃烧科学与技术》2024年第3期295-301,共7页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(52106153);江苏省自然科学基金资助项目(BK20210760).

摘　　要：为弄清喷嘴内燃油流动特性与涡线空化形态间的关系,阐明旋涡流动对涡线空化初生、发展的影响机制.本研究基于RSM湍流模型结合VOF多相流模型和修正的Zwart-Gerber-Belamri空化模型开展了不同针阀升程与喷孔高度下喷嘴内涡线空化特性数值模拟研究.结果表明:不同针阀升程下喷嘴内均产生了强烈的涡线空化,当针阀升程较低时,小尺度相干涡团加剧了喷孔内纵向涡核心区的不稳定性,影响了涡线空化形态的连续性.随着针阀升程增大,旋流区直接贯穿两个喷孔,小尺度相干涡团被抑制,喷孔内形成了稳定的强纵向涡核结构.此外,随着喷孔高度减小,喷嘴sac腔内的强烈单涡核旋流逐渐变弱,且逐步演变为反向双涡核弱旋流.To investigate the relationship between the characteristics of swirling flow and vortex cavitation patterns in the nozzle and then to elucidate the influence of swirling flow on cavitation inception and development,the numerical simulations of vortex cavitation inside the nozzle were conducted with different needle lifts and hole heights.The RSM turbulence model was adopted together with the VOF multiphase flow model and the modified Zwart-Gerber-Belamri cavitation model.Results show that strong vortex cavitation occurred inside the nozzle under different needle lifts.When the needle lift was small,the small-scale coherent vortices intensified the instability of the longitudinal vortex core area inside the nozzle,affecting the continuity of the vortex cavitation pattern.With the increase of needle lift,the swirl flow area directly penetrated two injection holes,and the small-scale coherent vortices were suppressed,forming a stable and strong longitudinal vortex core structure inside the nozzle.In addition,as the nozzle height decreases,the strong single-core swirl flow inside the nozzle sac chamber gradually weakened and evolved into a weak reverse double-core swirl flow.

关 键 词：涡线空化 数值模拟 针阀升程 喷孔高度 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]