- Access by Xinjiang University
Dynamics of paramagnetic and ferromagnetic ellipsoidal particles in shear flow under a uniform magnetic field
Phys. Rev. Fluids 3, 084201 – Published 14 August, 2018
DOI: https://doi.org/10.1103/PhysRevFluids.3.084201
Abstract
We investigate the two-dimensional dynamic motion of magnetic particles of ellipsoidal shapes in shear flow under the influence of a uniform magnetic field. In the first part, we present a theoretical analysis of the rotational dynamics of the particles in simple shear flow. By considering paramagnetic and ferromagnetic particles, we study the effects of the direction and strength of the magnetic field on the particle rotation. The critical magnetic-field strength, at which particle rotation is impeded, is determined. In a weak-field regime (i.e., below the critical strength) where the particles execute complete rotations, the symmetry property of the rotational velocity is shown to depend on the direction of the magnetic field. In a strong-field regime (i.e., above the critical strength), the particles are impeded at steady angles and the stability of these angles is examined. Under a uniform field, paramagnetic and ferromagnetic particles behave differently, in terms of the critical strength, symmetry property of the rotational velocity, and steady angles. In the second part, we use two-dimensional numerical simulations to study the implications of rotational dynamics for lateral migration of the particles in wall-bound shear flows. In the weak-field regime, the paramagnetic prolate particles migrate away when the field is applied perpendicular to the flow and towards the bounded wall when the field is applied parallel to the flow. Ferromagnetic particles exhibit negligible migration under fields that are parallel or perpendicular to the flow. The different lateral migration behaviors are due to the difference in the symmetry property of particle rotational velocity. In the strong-field regime, the particles are impeded at different stable steady angles, which result in different lateral migration behaviors as well. The fundamental insights from our work demonstrate various feasible strategies for manipulating paramagnetic and ferromagnetic particles.
Physics Subject Headings (PhySH)
Article Text
References (26)
- J. Oberteuffer, Magnetic separation: A review of principles, devices, and applications, IEEE Trans. Magn. 10, 223 (1974).
- C. Liu, T. Stakenborg, S. Peeters, and L. Lagae, Cell manipulation with magnetic particles toward microfluidic cytometry, J. Appl. Phys. 105, 102014 (2009).
- J. Dobson, Magnetic nanoparticles for drug delivery, Drug Dev. Res. 67, 55 (2006).
- L. Thiên-Nga, K. Hernadi, E. Ljubović, S. Garaj, and L. Forró, Mechanical purification of single-walled carbon nanotube bundles from catalytic particles, Nano Lett. 2, 1349 (2002).
- G. Friedman and B. Yellen, Magnetic separation, manipulation and assembly of solid phase in fluids, Curr. Opin. Colloid Interface Sci. 10, 158 (2005).
- R. Zhou, F. Bai, and C. Wang, Magnetic separation of microparticles by shape, Lab. Chip 17, 401 (2017).
- R. Zhou, C. A. Sobecki, J. Zhang, Y. Zhang, and C. Wang, Magnetic control of lateral migration of ellipsoidal microparticles in microscale flows, Phys. Rev. Appl. 8, 024019 (2017).
- D. Matsunaga, F. Meng, A. Zöttl, R. Golestanian, and J. M. Yeomans, Focusing and Sorting of Ellipsoidal Magnetic Particles in Microchannels, Phys. Rev. Lett. 119, 198002 (2017).
- D. Matsunaga, A. Zöttl, F. Meng, R. Golestanian, and J. M. Yeomans, Far-field theory for trajectories of magnetic ellipsoids in rectangular and circular channels, J. Appl. Math. 83, 767 (2018).
- J. Happel and H. Brenner, Low Reynolds Number Hydrodynamics: With Special Applications to Particulate Media (Springer Science + Business Media, New York, 2012), Vol. 1.
- N. Pamme, Magnetism and microfluidics, Lab. Chip 6, 24 (2006).
- A. Okagawa, R. G. Cox, and S. G. Mason, Particle behavior in shear and electric fields. VI. The microrheology of rigid spheroids, J. Colloid Interface Sci. 47, 536 (1974).
- R. S. Allan and S. G. Mason, Particle behavior in shear and electric fields. II. Rigid rods and spherical doublets, Proc. R. Soc. London Ser. A 267, 62 (1962).
- S. T. Demetriades, Effect of electrostatic fields on the orientation of colloidal particles immersed in shear flow, J. Chem. Phys. 29, 1054 (1958).
- Y. Almog and I. Frankel, The motion of axisymmetric dipolar particles in homogeneous shear flow, J. Fluid Mech. 289, 243 (1995).
- G. B. Jeffery, The motion of ellipsoidal particles immersed in a viscous fluid, Proc. R. Soc. London Ser. A 102, 161 (1922).
- J. A. Stratton, Electromagnetic Theory (Wiley, New York, 2007).
- I. Torres-Díaz and C. Rinaldi, Brownian dynamics simulations of ellipsoidal magnetizable particle suspensions, J. Phys. D 47, 235003 (2014).
- J. Zhang and C. Wang, Numerical study of lateral migration of elliptical magnetic microparticles in microchannels in uniform magnetic fields, Magnetochem. 4, 16 (2018).
- H. H. Hu, N. A Patankar, and M. Y. Zhu, Direct numerical simulations of fluid-solid systems using the arbitrary Lagrangian-Eulerian technique, J. Comput. Phys. 169, 427 (2001).
- Y. Ai, S. W. Joo, Y. Jiang, X. Xuan, and S. Qian, Pressure-driven transport of particles through a converging-diverging microchannel, Biomicrofluidics 3, 022404 (2009).
- Y. Ai, A. Beskok, D. T. Gauthier, S. W. Joo, and S. Qian, dc electrokinetic transport of cylindrical cells in straight microchannels, Biomicrofluidics 3, 044110 (2009).
- Y. Ai, Z. Zeng, and S. Qian, Direct numerical simulation of ac dielectrophoretic particle-particle interactive motions, J. Colloid Interface Sci. 417, 72 (2014).
- B. P. Ho and L. G. Leal, Inertial migration of rigid spheres in two-dimensional unidirectional flows, J. Fluid Mech. 65, 365 (1974).
- J. Feng, H. H. Hu, and D. D. Joseph, Direct simulation of initial value problems for the motion of solid bodies in a Newtonian fluid. Part 2. Couette and Poiseuille flows, J. Fluid Mech. 277, 271 (1994).
- J. Feng and D. D. Joseph, The unsteady motion of solid bodies in creeping flows, J. Fluid Mech. 303, 83 (1995).