School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, Singapore 639798.
Langmuir. 2011 Dec 20;27(24):14834-41. doi: 10.1021/la203931q. Epub 2011 Nov 15.
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.
本文报告了在均匀磁场作用下，超疏水表面上铁磁液滴变形的实验和数值结果。一个被不混溶的矿物油包围的水基铁磁液滴在平行于基底表面的磁场中被拉伸。结果表明，随着磁通密度的增加，液滴的宽度增加，高度减小。建立了一个数值模型来研究铁磁液滴的平衡形状。通过有限体积法求解包括磁场在内的物理场的控制方程。通过水平集方法跟踪两种不混溶液体之间的界面。在模型中实现了非线性磁化。实验结果与数值结果的比较表明，该数值模型可以很好地预测铁磁液滴在均匀磁场中的非线性变形。
