Abstract
We have investigated aggregation phenomena in a suspension composed of rod-like hematite particles, which have a magnetic moment normal to the particle axis direction, by means of Brownian dynamics simulations. The present Brownian dynamics method takes into account the spin rotational Brownian motion about the particle axis in addition to the ordinary translational and rotational Brownian motion. We have investigated the influence of the magnetic particle-field and particle-particle interactions, the shear rate and the volumetric fraction of particles on particle aggregation phenomena. Snapshots of aggregate structures are used for qualitative discussion and the cluster size distribution, radial distribution function and orientational correlation functions of the direction of particle axis and the magnetic moment are focused on for quantitative discussion. The raft-like clusters are significantly formed at a magnetic particle-particle interaction much larger than that for a magnetic spherical particle suspension. An applied magnetic field enhances the formation of raft-like clusters.
