变形影响下液滴热毛细迁移运动的瞬态行为  

Transient behavior of the thermocapillary migration of drops under the influence of deformation

作　　者：常磊[1] 尹兆华[1] 胡文瑞[1] 

机构地区：[1]中国科学院力学研究所国家微重力实验室,北京100190

出　　处：《中国科学：物理学、力学、天文学》2011年第8期960-968,共9页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：中国科学院知识创新工程重要方向项目资助(编号:KJCX2-YW-L08)

摘　　要：该文研究了在变形影响下的液滴热毛细迁移运动的瞬态行为.研究采波前追踪法描述可变形液滴的运动界面,整个控制方程使用有限差分法进行离散求解.随着液滴向高温区域迁移,液滴界面上平均界面张力不断减小,导致液滴变形不断增大.为此我们引入了一个实时毛细数以描述迁移过程中液滴在不同温度下的界面张力大小.研究发现随着液滴变形不断增大,密度小于/大于母液密度的液滴迁移速度会持续降低/增加.The transient thermocapillary migration behavior of drops with nontrivial deformation is studied.The finite difference method is employed to solve incompressible Navier-Stokes equations coupled with the energy equation and the front-tracking method is adopted to track the moving deformable drop interface.When the drop migrates to the warm region,its deformation increases with the decrease of its average interfacial tension.In order to indicate the temperature impact on the interfacial tension,a local capillary number is introduced in this paper.It is found that,when the drop density is smaller/larger than that of the bulk fluid,the drop velocity decreases/increases with the increase of the drop deformation.

关 键 词：液滴热毛细迁移 变形 密度比 瞬态行为 

分 类 号：O363.2[理学—流体力学]