Magnetically Mediated Formation of Ferrofluid Emulsion

This paper reports both experimental and numerical investigations of the formation process of ferrofluid emulsion with and without an applied magnetic field. The droplets are formed in a flow-focusing and T-junction configuration. In the experiment, a homogenous magnetic field was generated using an electromagnet. The presence of the magnetic field in the flow direction affects the formation process and changes the size of the droplets. In both configurations, the change in the droplet size depends on the magnetic field strength and the flow rates. A numerical model was used to investigate the force balance during the droplet breakup process. The particle level set method was employed to capture the interface movement between the continuous fluid and the dispersed fluid. The process of the droplet formation and the flow field is discussed for both cases with and without the magnetic field. Finally, experimental and numerical results are compared. The results show that the polarity of the magnetic field does not affect the formation process.