Effect of magnetic field on expansion of ferrofluid-encapsulated microbubble  

作　　者：杜芷玮 李凡 潘瑞琪 莫润阳 王成会 Zhiwei Du;Fan Li;Ruiqi Pan;Runyang Mo;Chenghui Wang(Shaanxi Key Laboratory of Ultrasonics,Shaanxi Normal University,Xi'an 710119,China)

机构地区：[1]Shaanxi Key Laboratory of Ultrasonics,Shaanxi Normal University,Xi'an 710119,China

出　　处：《Chinese Physics B》2023年第6期316-322,共7页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 12074238, 11974232, and 11774212)。

摘　　要：Magnetic microbubbles(MMBs) have great potential applications in drug delivery and target therapy because they can be controlled by magnetic fields. In this paper, dynamic equations are derived by Lagrangian formalism and the behavior of MMBs subject to a combination field of magnetic and ultrasound field in an incompressible infinite fluid is analyzed numerically. The results show that the magnetic field can promote bubble expansion and hinder its translational motion,and both the enhancement and obstruction effects will weaken with the decrease of bubble size. The initial translational velocity has almost no effect on bubbles motion. Besides, the maximum expansion radius of MMBs increases with the ferrofluid shell thickness, while that of the common MBs is just the opposite. In addition, the periodic change of Levich viscous drag caused by the rebound leads to the step-like translational motion. Finally, the ferrofluid-shell model can be replaced by the model of non-magnetic microbubbles in magnetic liquid at high driving frequency.

关 键 词：magnetic microbubbles ultrasound magnetic field translational motion 

分 类 号：O482.5[理学—固体物理]