Nonlinear deformation of a ferrofluid droplet in a uniform magnetic field
Ramanujan, Raju V.
Date of Issue2011
School of Mechanical and Aerospace Engineering
This paper reports experimental and numerical results of the deformation of a ferroﬂuid droplet on a superhydrophobic surface under the eﬀect of a uniform magnetic ﬁeld. A water-based ferroﬂuid droplet surrounded by immiscible mineral oil was stretched by a magnetic ﬁeld parallel to the substrate surface. The results show that an increasing ﬂux density increases the droplet width and decreases the droplet height. A numerical model was established to study the equilibrium shape of the ferroﬂuid droplet. The governing equations for physical ﬁelds, including the magnetic ﬁeld, are solved by the ﬁnite volume method. The interface between the two immiscible liquids was tracked by the level-set method. Nonlinear magnetization was implemented in the model. Comparison between experimental and numerical results shows that the numerical model can predict well the nonlinear deformation of a ferroﬂuid droplet in a uniform magnetic ﬁeld.
© 2011 American Chemical Society. This is the author created version of a work that has been peer reviewed and accepted for publication by Langmuir, American Chemical Society. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [DOI: http://dx.doi.org/10.1021/la203931q].