The investigation of capture behaviors of different shape magnetic sources in the high-gradient magnetic field

In this paper, we simulate the capture behavior and the advection–diffusion behavior of magnetic particles in the cross-section of different curvature magnetic sources which bring the high-gradient magnetic field with the time evolution. The results show that the capture behavior is affected not only by the fluid velocities, dynamic viscosity, particle size, and susceptibility, but also affected by the shape of magnetic sources. Although the curvature of magnetic source dominates the gradient of the magnetic field, enough large area facing the incoming fluid is still the main factor which affects the capture efficiency. The distribution of concentration in the cross-section area and source surface are both affected by the surface curvature, especially under the relatively stronger interaction of magnetic source. The influence by surface curvature becomes much more evident, larger curvature costs shorter time for particles accumulation than the smaller one. The magnetic force competing with the fluid drag force and the body force exerted on the fluid medium could both decide the concentration distribution.