液滴撞击凹凸槽道表面液膜的动态演变  

Dynamic behavior of droplet impact on the concave surface with liquid film

作　　者：周鑫[1] 王宏[1] 朱恂[1] 陈蓉[1] 廖强[1] 丁玉栋[1] ZHOU Xin;WANG Hong;ZHU Xun;CHEN Rong;LIAO Qiang;DING Yudong(Key Laboratory of Low-Grade Energy Utilization Technologies&Systems of Ministry of Education,Institute of Engineering Thermophysics,Chongqing University,Chongqing 400030,China)

机构地区：[1]重庆大学工程热物理研究所低品位能源利用技术及系统教育部重点实验室,重庆400030

出　　处：《中国科学院大学学报（中英文）》2020年第2期255-262,共8页Journal of University of Chinese Academy of Sciences

基　　金：国家自然科学基金(51676022);中央高校基本科研业务经费项目(2018CDXYDL0001);重庆市留学人员回国创新支持计划项目(cx2018053)。

摘　　要：为研究固体表面结构对液滴撞击液膜后演变行为的影响规律,采用CLSVOF方法模拟液滴撞击不同尺寸槽道上的表面液膜的流动过程,获得不同槽道高度和宽度时液滴撞击液膜后的演变行为,探索撞击速度、液膜黏度和表面张力对撞击后液膜铺展行为、水花飞溅高度和二次液滴形成的影响。结果表明,槽道结构对液滴撞击液膜后的动态行为具有显著影响,随着槽道高度的增加,冠状水花厚度越薄,越容易产生二次液滴;随着液膜黏度的增大,则抑制冠状水花形成与二次液滴的产生;液膜表面张力减小时,射流更加明显,二次液滴数更多,飞溅现象提前,冠状水花消失时间延后。In this paper we present results of a numerical investigation into a single drop impact on a rectangular grooved substrate with thin liquid film covering it. Particularly,effects of the height and width of the ridge on surface and dynamic behavior of droplet impact into thin liquid film were mainly studied. Simulations were performed using CLSVOF( coupled level-set and VOF) to track the air-water interface accurately and to keep conservation of mass at the same time. Results show that the structure of grooved surface has significant influence on the evolution of liquid film when droplet impacts on it. With the increase of rectangular groove height,the thickness of the coronal water becomes thin and the secondary droplets produce easily. Increase of the viscosity of liquid film inhibits coronal water flower formation and secondary droplet generation. When the surface tension of liquid film reduces,the jet is obvious and more secondary droplets produce. The splash phenomenon is advanced,and the disappearance of the crown water flower is delayed. Our research sheds some lights on the fundamental understanding of many industrial phenomena.

关 键 词：液滴撞击 多相流 凹凸槽道 CLSVOF 

分 类 号：TK124[动力工程及工程热物理—工程热物理]