Ferrofluid

Ferrofluids (sometimes referred as magnetic liquids) are colloidal suspensions of magnetic nanoparticles, represent a special class of magnetic fluids and are manufactured fluids consisting of dispersions of magnetized nanoparticles in a variety of non-magnetic liquid carriers. They were originally invented independently around the same time in the early 1960s at NASA Lewis Laboratories, and aslo by Dr. R. E. Rosensweig et al. at AVCO Space Systems. Typically, particles within such colloidal suspension are about 10 nanometers (nm) in diameter and suspended in either water or oil.

They are stabilized against agglomeration by the addition of a surfactant monolayer onto the particles. In the absence of an applied magnetic field, the magnetic nanoparticles are randomly oriented, the fluid has zero net magnetization, and the presence of the nanoparticles provides a typically small alteration to the fluid’s properties such as viscosity and density.

When a sufficiently strong magnetic field is applied, the ferrofluid flows toward regions of the magnetic field, properties of the fluid such as the viscosity are altered, and the hydrodynamics of the system can be significantly changed.

Since the first successful production of stable ferrofluids in the early 1960s (Papell 1964) the field of ferrofluid research developed quickly in different branches:

  • Physics: connected to the fundamental description and characterization.
  • Chemistry: as basis for ferrofluid preparation.
  • Engineering: to prepare and provide application.

The field of ferrofluid research is relatively young compared to the investigation that have been done in fluid dynamics in general. The famous book “Ferrohydrodynamics” by Rosensweig 1985 is one of the standard textbooks in this field which must be mentioned here. It covers various areas in this research field, synthesis and properties of magnetic fluids, foundation of ferrohydrodynamics theory, hydrodynamics in ferrofluids, as well as problems and applications.

However, the term ferrohydrodynamics was established first by Neuringer and Rosensweig 1964. This includes the continuum description of the flow behavior of magnetic fluids in the presence of magnetic fields. Later Shliomis 1972 developed a theory including the experimental findings of magnetoviscous effects by Rosensweig et al. 1969 and McTague 1969. Further to mention is the book “Magnetic Fluids” by Blumes et al. 1997 which focuses on the rheology of ferrofluids in more detail, also including theoretical discussion of the magnetoviscous effect, rotational viscosity variation of shear rate, and many more.

In this context also to mention is the earlier work by Blumes et al. 1986, which despite being mainly devoted to conducting fluids and the action of Lorenz forces, also elucidates the effects of heat and mass transfer in ferrofluids. The application of ferrofluids and magnetic fluids in general is summarized in the books by Berkovsky and Bashtovoy 1993 & 1996.

They provide a wide overview of various possible uses of ferrofluids in different fields/areas, reaching from separation over mechanical positioning towards medical applications. Nowadays, ferrofluids are utilized in a wide variety of applications, ranging from their use in computer hard drives and as liquid seals in rotating systems to their use in laboratory experiments to study geophysical flows and the development of microfluidic devices.

  • Magnetic fluid

References

  • A. Akonura, and R. M. Lueptow, “Three-dimensional velocity field for wavy Taylor-Couette flow,” Physics of Fluids, 15:4, 2003.
  • S. Altmeyer, C. Hoffmann, A. Leschhorn an M. Lücke, “Influence of homogeneous magnetic fields on the flow of a ferrofluid in the Taylor-Couette system,” Phys. Rev. E, 82:016321, 2010.
  • S. Altmeyer, Y. Do, and J. M. Lopez, “Influence of an inhomogeneous internal magnetic field on the flow dynamics of ferrofluid between differentially rotating cylinders,” Phys. Rev. E, 85:066314, 2012.
  • S. Altmeyer, Y. Do, and J. M. Lopez, “Effect of elongational flow on ferrofuids under a magnetic field,” Phys. Rev. E, 88:013003, 2013.
  • S. Altmeyer, Y. Do, and Ying-Cheng Lai, “Transition to turbulence in Taylor-Couette ferrofluidic flow,” Scientific Reports, 5:10781, 2015.
  • S. Altmeyer, “Interaction of Magnetic Fields on Ferrofluidic Taylor-Couette Flow,“ in Pattern Formation and Stability in Magnetohydrodynamics, IntechOpen, 2018.
  • S. Altmeyer, “Agglomeration effects in rotating ferrofluids,” J. Magn. Magn. Mater, 482:239-250, 2019.
  • O. Ambacher, S. Odenbach, and S. Stierstadt, “Rotational viscosity in ferrofluids,” Z. Phys. B, 86:29-32, 1992.
  • B. Berkovsky, V. F. Medvedev, and M. S. Krakov, Magnetic Fluids, Engineering Applications, Oxford University Press, 1993.
  • B. Berkovsky, and V. Bashtovoy, Magnetic Fluids and Applications Handbook, Begel, House, New York, 1996.
  • E. Blums, Yu. A. Mikhailov, and R. Ozols Heat and Mass Transfer in MHD Flows, World Scientific Publishing, 1986.
  • E. Blums, A. Cebers, and M. M. Maiorov Magnetic Fluids, Walter de Gruyter, Berlin, 1997.
  • P. E. Bodenschatz, W. Pesch, and G. Ahlers, “Recent developments in Rayleigh-Bénard convection,” Annu. Rev. Fluid Mech., 32:709, 2000.
  • P. Debye, “Polar molecules,” The Chemical Catalog Company, New York, 1929.
  • C. Egbers, and G. Pfister Physics of rotating fluids, proc. Bremen 1999, Springer 549, 445, 2000.
  • P. C. Fannin and S. W. Charles, “The study of a ferrofluid exhibiting both Brownian and Néel relaxation,” J. Phys. D: Appl. Phys., 22:187, 1988.
  • P. C. Fannin and S. W. Charles, “Measurement of the Néel relaxation of magnetic particles in the frequency range 1 kHz to 160 MHz,” J. Phys. D: Appl. Phys., 24:76, 1991.
  • Data sheets, www.ferrofluidics.de
  • M. Gellert, G. Rüdiger, and R. Hollerbach, “Helicity and α-effect by current-driven instabilities of helical magnetic fields,” Monthly Notices Royal Astro. Soc., 414:2969-2701, 2011.
  • J. E. Hart, “Ferromagnetic rotating Couette flow: The role of magnetic viscosity,” J. Fluid Mech., 453:21, 2002.
  • M. Holderied, “Rotational viscosity of ferrofluids and the Taylor instability in magnetic field,” Z. Phys. B, 70:431-433, 1988.
  • E. Kneller Ferromagnetismus, 1st edition, Springer-Verlag, Berlin, 1962.
  • Langevin, “Magnétisme et thérie des electrons,” Ann. Chim. Phys., 5:70, 1905.
  • M. A. Martsenyuk, Y. L. Raikher, and M. I. Shliomis “On the kinetics of magnetization of suspensions of ferromagnetic particles,” Sov. Phys. JETP, 38:413, 1974.
  • P. Matura, and M. Lücke “Thermomagnetic convection in a ferrofluid layer exposed to a time-periodic magnetic field,” Phys. Rev. E, 80:026314, 2009.
  • J. P. McTague, “Magnetoviscosity of Magnetic Colloids,” J. Chem. Phys., 51:133-136, 1969.
  • L. Néel, “Effects of thermal fluctuations on the magnetization of small particles,” C. R. Acad. Sci. Paris, 228:664, 1949.
  • J. L. Neuringer, and R. E. Rosensweig, “Ferrohydrodynamics,” Phys. Fluids, 7:12, 1927.
  • M. Niklas, “Influence of magnetic fields on Taylor vortex formation in magnetic fluids,” Z. Phys. B, 68:493, 1987.
  • M. Niklas, M. Müller-Krumbhaar, and M. Lücke, “Taylor-vortex flow of ferrofluids in the presence of general magnetic fields,” J. Magn. Magn. Mater., 81:29, 1989.
  • S. Odenbach, and H. W. Müller, “Stationary Off-Equilibrium Magnetization in Ferrofluids under Rotational and Elongational Flow,” Phys. Rev. Lett., 89:037202, 2002.
  • S. Odenbach, and H. W. Müller, “Ferrofluid microstructure explored by rheometry and magnetization relaxation,” J. Magn. Magn. Mater., 289:242, 2005.
  • S. Odenbach, and S. Thurm, Magnetoviscous Effects in Ferrofluids, In Ferrofluids – Magnetically Controllable Fluids and their Applications, Vol 71, pp. 185-201, Springer, Berlin 2002.
  • S. Odenbach, T. Rylewicz, and H. Rath, “Investigation of the Weissenberg effect in suspensions of magnetic nanoparticles,” Physics of Fluids, 11:2901, 1999.
  • S. Odenbach, Magnetic Fluids, Springer Lecture Notes in Physics, Heidelberg: Springer, 2003.
  • S. S. Papell, Low viscosity magnetic fluid obtained by the colloidal suspension of magnetic particles, US Patent Specification, 3215572, 1964.
  • E. A. Peterson, and D. A. Krueger, “Reversible, field induced agglomeration in magnetic colloids,” J. Colloid Interface Sci., 62:24-34, 1977.
  • M. Reindl, A. Leschhorn, M. Lücke, S. Odenbach, “Flow control of magnetic fluids exposed to magnetic fields,” J. Phys.: Conf. Ser., 149:012109, 2009.
  • M. Reindl, and S. Odenbach, “Influence of a homogeneous axial magnetic field on Taylor-Couette flow of ferrofluids with low particle-particle interaction,” Expts. Fluids, 50:375, 2011.
  • M. Reindl, and S. Odenbach, “Effect of axial and transverse magnetic fields on the flow behavior of ferrofluids featuring different levels of interparticle interaction,” Phys. Fluids, 23:093102, 2011.
  • R. E. Rosensweig, Ferrohydrodynamics, Cambridge University Press, 1985.
  • R. E. Rosensweig, R. Kaiser, and G. Miskolczy, “Viscosity of magnetic fluid in a magnetic field,” J. Coll. Int. Sci., 29:4, 1969.
  • M. I. Shliomis, “Effective Viscosity of Magnetic Suspensions”, Sov. Phys. JETP, 34:1291-1294, 1972.
  • A. Storozhenkoa, R. Stannariusb, A. O. Tantsyuraa, and I. A. Shabanova, “Measurement of the torque on diluted ferrofluid samples in rotating magnetic fields”, J. Magn. Magn. Mater., 413:66, 2016.
  • G. I. Taylor, “Stability of a viscous liquid contained between two rotating cylinders,” Philos. Trans. R. Soc. London, Ser. A, 223:289-343, 1923.

Leave a Comment