Numerical Modeling of Ferrofluid Droplets in Magnetic Fields

Abstract

The motion and shape of a ferrofluid droplet placed in a non‐magnetic viscous fluid and driven by a magnetic field are modeled numerically. The governing equations are the Maxwell equations, momentum equation and incompressibility. The numerical simulation uses a volume‐of‐fluid algorithm with a continuum‐surface‐force formulation for an axisymmetric geometry. The deformations in the drop under non‐uniform magnetic fields are simulated. Droplets exhibit shape changes along the applied magnetic field. We have found that the ferrofluid droplet forms a prolate ellipsoid in the presence of a non‐uniform magnetic field. For higher magnetic field strengths, the droplet undergoes dramatic deformation. This in turn influences the motion of the droplet through the viscous medium.