磁场作用下单个气泡在磁性液体中的行为  

Behavior of single bubble rising in magnetic fluid under magnetic field

作　　者：毕勤成[1] 施东晓[1] 何永清[1] 邱晟华[1] 

机构地区：[1]西安交通大学动力工程多相流国家重点实验室,陕西西安710049

出　　处：《热科学与技术》2010年第3期189-193,共5页Journal of Thermal Science and Technology

基　　金：国家高技术研究发展计划(863计划)专题课题资助项目(2008AA05Z417);国家自然科学基金资助项目(11072189)

摘　　要：采用可视化的方法对磁场作用下注有磁性液体的矩形窄通道中气泡的上升运动进行了试验研究,定性分析了磁场对气泡上升速度、轨迹及形状的影响。试验工质采用体积分数6.33%的水基Fe3O4磁性液体,同时对比了水中气泡的上升运动。矩形窄通道的宽度分别为1.32和2.04 mm,磁场为对称横向非均匀磁场,气泡由伸入通道底部的毛细管产生。试验结果表明:气泡在正梯度磁场区域做减速运动,在负梯度磁场区域做加速运动;施加垂直于气泡运动方向的横向磁场有助于增强气泡运动的稳定性,且气泡沿着磁场方向被拉长。Single bubble rising in rectangular mini-gaps filled with magnetic fluid under a symmetrical and nonuniform transverse magnetic field was studied visually,and the effect of the magnetic filed on the bubble velocity,trajectory and shape was studied and discussed qualitatively.Water-based Fe3O4 magnetic fluid with a particle volumetric concentration of 6.33% was filled in the gaps with widths of 1.32 mm and 2.04 mm,respectively,and the bubble was generated by a capillary tube inserted into the bottom of the gap.Experimental results show that a single bubble is decelerated in the region of positive gradient magnetic field and accelerated in the region of negative gradient magnetic field,and the shape of the bubble is elongated in the direction of the magnetic field.In addition,the trajectory of the bubble becomes more stable due to the effect of the magnetic field.

关 键 词：磁性液体 磁场 气泡 上升速度 变形 

分 类 号：O359[理学—流体力学]