Numerical simulation of contact and separation of magnetic particles under uniform magnetic field

Abstract

Abstract Under the action of an external magnetic field, the magnetic particles will be arranged along the direction of the magnetic field. The laws of physics that control these processes are well described in the literature. However, when the magnetic particles move in the fluid, the magnetic particles with different initial distances have different mutual influences, so there will be different laws of motion. Therefore, based on the motion theory of magnetic particles in Stokes fluid, this article discusses the motion law of the contact and separation of two circular magnetic particles in Newtonian fluid. First, we conduct theoretical and simulation modeling of two magnetic particles under the action of a uniform magnetic field, and verify the correctness of the simulation through experiments; secondly, we use numerical simulation to study the angle of repulsion and attraction of magnetic particles at different initial distances, and analyze at the same time the changes in the trajectory, speed, torque and force of magnetic particles in the process of motion are studied. Finally, the influence of external field conditions on the phenomenon of contact and separation of magnetic particles is studied. The study found that even when the initial angle between the magnetic particles is 90° with the direction of the magnetic field, the magnetic particles with different initial distances will repel under the action of repulsive force and then contact again and keep repelling these two states, a better explanation the reason for the agglomeration of magnetic particles at close range is explained.