To overcome the disadvantages of VOF and Level Set methods in the research of ferrofluid two-phase flows
a numerical method coupling the flow field with magnetic field of ferrofluids was developed
where the evolution of interface was captured by the VOSET(coupled Volume-of-Fluid and Level Set)method
and the magnetic force was added into the momentum equation as a source term. To verify the accuracy of solving magnetic fields
a 2D analytical solution of Maxwell equations was derived and used to validate the numerical solution. The numerical results were in good agreement with the theoretical values. Then
the equilibrium shape of a ferrofluid droplet was simulated which verified the validity of our numerical method. Based on the proposed method
the droplet oscillation and rising bubble problems in the presence of magnetic fields were numerically investigated. The results showed that both the droplet and bubble were stretched in the direction of magnetic field
and the increase in either magnetic field strength or magnetic susceptibility would lead to a more significant deformation. Note that the magnetic field lines were distorted in the vicinity of interface with the bending direction pointing to the medium with a higher susceptibility.
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references
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