Department of Engineering Physics, Electronics and Mechanics, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan.
J Phys Condens Matter. 2010 Aug 18;22(32):324103. doi: 10.1088/0953-8984/22/32/324103. Epub 2010 Jul 15.
Microstructure formation of magnetic particles and nonmagnetic particles in magnetorheological (MR) fluids is investigated using the particle method simulation based on simplified Stokesian dynamics. Spherical nonmagnetic particles are rearranged in the field direction due to the formation of magnetic particles in chain-like clusters. Cluster formation of spherocylindrical magnetic particles forces spherical nonmagnetic particles to arrange in the direction of the field. In contrast, the spherocylindrical nonmagnetic particles, with an aspect ratio of two or three, are not sufficiently rearranged in the field direction by cluster formation of spherical magnetic particles. Even after cluster formation in the presence of a magnetic field, the uniformity of distribution of particles on the plane perpendicular to the field direction shows very little change. However, the deviation of uniformity in particle distribution is reduced when the volume fraction of magnetic particles is the same as that of nonmagnetic particles.
采用基于简化斯托克斯动力学的颗粒方法模拟，研究了磁流变（MR）液中磁性颗粒和非磁性颗粒的微观结构形成。由于链状簇中磁性颗粒的形成，球形非磁性颗粒在磁场方向上重新排列。球形磁流变颗粒的簇形成迫使球形非磁性颗粒在磁场方向上排列。相比之下，具有两个或三个纵横比的长球形非磁性颗粒在球形磁性颗粒的簇形成作用下，不能充分地在磁场方向上重新排列。即使在磁场存在的情况下形成簇后，垂直于磁场方向的平面上颗粒分布的均匀性变化也很小。然而，当磁性颗粒的体积分数与非磁性颗粒的体积分数相同时，颗粒分布均匀性的偏差会减小。
