Dynamics of three ferrofluid droplets in a rotating magnetic field

Expand
  • 1.School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
    2.State Key Laboratory of Intelligent Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
Xinping ZHOU, E-mail: xpzhou08@hust.edu.cn

Received date: 2024-10-19

  Revised date: 2024-12-11

  Online published: 2025-03-04

Supported by

Project supported by the National Natural Science Foundation of China (No. 12372263)

Copyright

© Shanghai University 2025

Abstract

Two-dimensional (2D) direct numerical simulations on the dynamics of three identical ferrofluid droplets suspended in a non-magnetic ambient fluid under a rotating uniform magnetic field are conducted, and the motion and deformation of the three ferrofluid droplets are studied in this paper. Results show that there are four modes (i.e., the three droplets' direct coalescence (TC), the coalescence of two droplets and the subsequent planetary motion with the third droplet (CAP), the three droplets' planetary motion (TP), and the independent spin (IS)) for the three ferrofluid droplets, dependent on the magnetic Bond number (Bom) and the initial distance (d0) between two of the droplets. It is found that the decrease in d0 and the increase in Bom can make the droplets' mode change from the IS to the planetary motion, and then turn to the CAP. Furthermore, reducing Bom or d0 is helpful for the droplets to become merged.

Cite this article

Xinping ZHOU, Wencai XIAO, Qi ZHANG, Chunyue LIANG, Wanqiu ZHANG, Fei ZHANG . Dynamics of three ferrofluid droplets in a rotating magnetic field[J]. Applied Mathematics and Mechanics, 2025 , 46(3) : 591 -600 . DOI: 10.1007/s10483-025-3224-7

References

[1] PURI, K. and GANGULY, R. Particle transport in therapeutic magnetic fields. Annual Review of Fluid Mechanics, 46, 407–440 (2014)
[2] FAN, X. J., JIANG, Y. H., LI, M. G., ZHANG, Y. F., TIAN, C. N., MAO, L. Y., XIE, H., SUN, L. N., YANG, Z., and SITTI, M. Scale-reconfigurable miniature ferrofluidic robots for negotiating sharply variable spaces. Science Advance, 8(37), eabq16776 (2022)
[3] ROWGHANIAN, P., MEINHART, C. D., and CAMPàS, O. Dynamics of ferrofluid drop deformations under spatially uniform magnetic fields. Journal of Fluid Mechanics, 802, 245–262 (2016)
[4] ERDMANIS, J., KITENBERGS, G., PERZYNSKI, R., and CēBERS, A. Magnetic micro-droplet in rotating field: numerical simulation and comparison with experiment. Journal of Fluid Mechanics, 819, 350–382 (2017)
[5] LIU, K., GAO, Y., TANG, X., ZHANG, Y., BAI, X., and ZANG, D. Bubbling of ferrofluid droplets via coupled magnetic and sound fields. Advanced Materials Interfaces, 10(7), 2201724 (2023)
[6] CHEN, C. Y., HSUEH, H. C., WANG, S. Y., and LI, Y. H. Self-assembly and novel planetary motion of ferrofluid drops in a rotational magnetic field. Microfluidics and Nanofluidics, 18, 795–806 (2015)
[7] QIU, M., AFKHAMI, S., CHEN, C. Y., and FENG, J. J. Interaction of a pair of ferrofluid drops in a rotating magnetic field. Journal of Fluid Mechanics, 846, 121–142 (2018)
[8] STIKUTS, A. P., PERZYNSKI, R., and CēBERS, A. Spontaneous order in ensembles of rotating magnetic droplets. Journal of Magnetism and Magnetic Materials, 500, 166304 (2020)
[9] LI, X., YU, P., NIU, X. D., LI, D. C., and YAMAGUCHI, H. A magnetic field coupling lattice Boltzmann model and its application on the merging process of multiple-ferrofluid-droplet system. Applied Mathematics and Computation, 393, 125769 (2021)
[10] LEE, W. K., SCARDOVELLI, R., TRUBATCH, A. D., and YECKO, P. Numerical, experimental, and theoretical investigation of bubble aggregation and deformation in magnetic fluids. Physical Review E, 82(1), 016302 (2010)
[11] LI, Q. Z., LU, Z. L., ZHOU, D., NIU, X. D., GUO, T. Q., DU, B. C., and LI, Y. Magnetic field-induced self-assembly of multiple nonmagnetic bubbles inside ferrofluid. Physics of Fluids, 33(10), 103307 (2021)
[12] ZHOU, X., XIAO, W., ZHANG, Q., ZHANG, W., and ZHANG, F. A droplet in a ferrofluid droplet under a rotating magnetic field. Journal of Engineering Mathematics, 146, 6–26 (2024)
[13] POPINET, S. Gerris: a tree-based adaptive solver for the incompressible Euler equations in complex geometries. Journal of Computational Physics, 190, 572–600 (2003)
[14] POPINET, S. An accurate adaptive solver for surface-tension-driven interfacial flows. Journal of Computational Physics, 228, 5838–5866 (2009)
[15] AFKHAMI, S., TYLER, A. J., RENARDY, Y., RENARDY, M., PIERRE, T. G., WOODWARD, R. C., and RIFFLE, J. S. Deformation of a hydrophobic ferrofluid droplet suspended in a viscous medium under uniform magnetic fields. Journal of Fluid Mechanics, 663, 358–384 (2010)
Outlines

/

APS Journals | CSTAM Journals | AMS Journals | EMS Journals | ASME Journals