中文摘要：

通过计算机模拟及实验研究了磁流变液颗粒在渐变磁场作用下的成链过程。首先从理论上建立了磁流变液成链过程的物理模型,采用蒙特卡罗方法模拟了其在渐变磁场作用下成链的详细过程。其次,采用光学显微镜观察了磁流变液在渐变磁场作用下的成链过程。数值模拟和实验结果表明,在平行磁场中,当外部磁场为零时,磁流变液的磁性颗粒处于随机分布状态。随着磁场强度的增加,磁性颗粒产生磁团聚形成链状絮凝体,进而由二连体或三连体发展到多连体,甚至网状及柱状结构;在倾斜磁场中,磁流变液中的聚合链也同时旋转,磁性颗粒沿着磁场方向从小链逐渐增大到大链,最后全部沿着磁场方向呈链状或柱状排列。研究结果对优化磁流变液材料的配置和设计高性能磁流变液装置具有重要意义。

英文摘要：

Comprehensive theoretical and experimental analyses of chain-formation process for magnetorheological fluid（MRF） are performed in this paper.Firstly,the physical model for the chain-formation process has been established.The Monte Carlo method has been used to simulate the chain-formation process under the gradient magnetic field.Secondly,we study the chain-formation process of MRF under the magnetic field by experiment.Numerical and experimental studies show that： when the magnetic field direction is parallel to the level of magnetorheological fluid and the external magnetic field is zero,magnetic particles are disordered.when the magnetic field strength increases gradually,the magnetic particles form smaller chains,mesh and even columnar structure along the direction of magnetic field;When there is a certain angle between the magnetic field direction and magnetorheological fluid level,with the increase of magnetic field,in the vertical direction of the level,magnetic particles form the small chains and then become the large chains along the magnetic field,finally,all are in the arrangement of chains or columnar chain.The results of this study can provide a theoretical basis for optimizing MRF parameters and design of high-performance MRF devices.