Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Direct Simulation of the Magnetic Interaction of Elliptic Janus Particles Suspended in a Viscous Fluid

점성유체에 분산된 타원형 야누스 입자의 자성 상호작용에 관한 직접수치해석

  • Kim, Hei Eun (School of Aerospace and Mechanical Engineering, Korea Aerospace Univ.) ;
  • Kang, Tae Gon (School of Aerospace and Mechanical Engineering, Korea Aerospace Univ.)
  • 김희은 (한국항공대학교 항공우주 및 기계공학부) ;
  • 강태곤 (한국항공대학교 항공우주 및 기계공학부)
  • Received : 2017.02.07
  • Accepted : 2017.04.11
  • Published : 2017.07.01
Download PDF
⟨ Previous Next ⟩

Abstract

The magnetic interaction between elliptic Janus magnetic particles are investigated using a direct simulation method. Each particle is a one-to-one mixture of paramagnetic and nonmagnetic materials. The fluid is assumed to be incompressible Newtonian and nonmagnetic. A uniform magnetic field is applied externally in a horizontal direction. A finite-element-based fictitious domain method is employed to solve the magnetic particulate flow in the creeping flow regime. In the magnetic problem, the magnetic field in the entire domain, including the particles and the fluid, is obtained by solving the governing equation for the magnetic potential. Then, the magnetic forces acting on the particles are calculated via a Maxwell stress tensor formulation. In a single particle problem, it is found that the orientation angle at equilibrium is affected by the aspect ratio of the particle. As for the two-particle interaction, the dynamics and the final conformation of the particles are significantly influenced by the aspect ratio, the orientation, and the spatial positions of the particles. For the given positions of the particles, the fluid flow is also influenced by the orientation of each particle. The self-assembly structure of the particles is not a fixed one, but it varies with the above-mentioned factors.

외부자기장에 의한 타원형 야누스 자성입자 사이의 자성 상호작용을 직접수치해석을 사용하여 분석하였다. 유한요소법에 기초한 가상영역법을 사용하여 입자계 유동해석을 수행하였고, 자기장 문제에서는 자성 포텐셜에 대한 지배방정식을 입자와 유체를 포함하는 전체영역에 대하여 풀어 자기장을 구하였다. 이 때 구해진 자기장으로부터 구한 맥스웰 응력을 사용하여 개별 입자에 작용하는 자기력이 계산된다. 입자의 운동과 최종적인 조립구조는 입자의 형상비, 개별 입자의 배향, 입자의 초기 분포에 크게 영향을 받는 것이 확인되었다. 또한 입자의 배향은 입자 주위의 유체 유동에도 영향을 주었다. 외부자기장에 의한 타원형 야누스 입자의 최종 조립구조는 앞서 언급한 인자들에 의해서 영향을 받은 것을 수치해석을 통해 확인할 수 있었다.

Keywords

References

  1. Gao, Y., Kang, T. G., Hulsen, M. A. and den Toonder, J. M. J., 2012, "Numerical and Experimental Study of a Rotating Magnetic Particle Chain in a Viscous Fluid," Phys. Rev. E, Vol. 86, p. 041503. https://doi.org/10.1103/PhysRevE.86.041503
  2. Pamme, N., 2006, "Magnetism and Microfluidics," Lab Chip, Vol. 6, pp. 24-38. https://doi.org/10.1039/B513005K
  3. Ganguly, R. and Puri, I. K., 2010, "Microfluidic Transport in Magnetic MEMS and BioMEMS," Wiley Interdiscip. Rev.-Nanomed. Nanobiotechnol. Vol. 2, pp. 382-399. https://doi.org/10.1002/wnan.92
  4. van Reenen, A., de Jong, A. M., den Toonder, J. M. J. and Prins, M. W. J., 2014, "Integrated Labon- chip Biosensing Systems based on Magnetic Particle Actuation - a Comprehensive Review," Lab Chip, Vol. 14, pp. 1966-1986. https://doi.org/10.1039/C3LC51454D
  5. Kawaguchi, H., 2000, "Functional Polymer Microspheres," Prog. Polym. Sci. Vol. 25, pp. 1171-1210. https://doi.org/10.1016/S0079-6700(00)00024-1
  6. Walther, A. and Müller, A. H. E., 2008, "Janus Particles," Soft Matter, Vol. 4, pp. 663-668. https://doi.org/10.1039/b718131k
  7. Walther, A. and Müller, A. H. E., 2013, "Janus Particles: Synthesis, Self-assembly, Physical Properties, and Applications," Chem. Rev., Vol. 113, pp. 5194-5261. https://doi.org/10.1021/cr300089t
  8. Yuet, K. P., Hwang, D. K., Haghgooie, R. and Doyle, P. S., 2010, "Multifunctional Superparamagnetic Janus Particles," Langmuir, Vol. 26, pp. 4281-4287. https://doi.org/10.1021/la903348s
  9. Ren, B., Ruditskiy, A., Song, J. H. K. and Kretzschmar, I., 2012, "Assembly Behavior of Iron Oxide-Capped Janus Particles in a Magnetic Field," Langmuir, Vol. 28, pp. 1149-1156. https://doi.org/10.1021/la203969f
  10. Seong, Y., Kang, T. G., Hulsen, M. A., den Toonder, J. M. J. and Anderson, P. D., 2016, "Magnetic Interaction of Janus Magnetic Particles Suspended in a Viscous Fluid," Phys. Rev. E, Vol. 93, p. 022607. https://doi.org/10.1103/PhysRevE.93.022607
  11. Kim, H. E., Kim, K., Ma, T. Y. and Kang, T. G., 2017, "Numerical Investigation of the Dynamics of Janus Magnetic Particles in a Rotating Magnetic Field," Korea-Aust. Rheol. J., Vol. 29, pp. 17-27. https://doi.org/10.1007/s13367-017-0003-5
  12. Kang, T. G., Gao, Y., Hulsen, M. A., den Toonder, J. M. J. and Anderson, P. D., 2013, "Direct Simulation of the Dynamics of Two Spherical Particles Actuated Magnetically in a Viscous Fluid," Comput. Fluids, Vol. 86, pp. 569- 581. https://doi.org/10.1016/j.compfluid.2013.08.003
  13. Kang, T. G., Hulsen, M. A. and den Toonder, J. M. J., 2012, "Dynamics of Magnetic Chains in a Shear Flow under the Influence of a Uniform Magnetic Field," Phys. Fluids, Vol. 24, p. 042001. https://doi.org/10.1063/1.4704822