Technical Papers and Presentations

This study investigates the effect of a uniform magnetic field on the lateral migration behavior of a ferrofluid droplet in a plane Poiseuille flow at arbitrary directions by means of numerical simulation. A numerical scheme called level set method in combination with the laminar two-phase flow features in the CFD Module of COMSOL Multiphysics^® simulation software, is used to solve the flow field both inside and outside of the droplet while the level set method is required to track the dynamic motion of the droplet interface which is suspended in another immiscible medium. A parabolic flow is generated by means of a pressure gradient. Magnetic field both inside and outside of the droplet is simulated using the AC/DC Module, and it is coupled to the flow domain using the volume force feature of the Laminar Flow interface. We found that at a low droplet Reynolds number (Re <0.05), the magnetic field direction can effectively manipulate the final equilibrium position of the droplet along a channel. Keeping the viscosity ratio fixed (i.e., λ = 1 ), at α = 0º, the droplet finds its equilibrium position closer to the bottom wall while at α = 45º and 90º  the droplet settles closer towards the channel center. Also, at a steady state the droplet is found to align itself towards the direction of the magnetic field.