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The interfacial stability of a ferromagnetic fluid

Published online by Cambridge University Press:  28 March 2006

M. D. Cowley
Affiliation:
Mechanical Engineering Department, Massachusetts Institute of Technology Present address: Department of Engineering, University of Cambridge.
R. E. Rosensweig
Affiliation:
Avco Space Systems Division, Wilmington, Massachusetts

Abstract

A normal magnetic field has a destabilizing influence on a flat interface between a magnetizable and a non-magnetic fluid. Stabilizing influences are provided by interfacial tension and gravity if the lighter fluid is uppermost. The critical level of magnetization for onset of the instability is derived for a fluid having a non-linear relation between magnetization and magnetic induction. Experiments using a magnetizable fluid, which contains a colloidal suspension of ferromagnetic particles, at interfaces with air and water are made and cover a wide range of density differences. Measurements confirm the prediction for critical magnetization, and it was found that, after onset, the interface took a new form in which the elevation had a regular hexagonal pattern. The pattern was highly stable, and the measured spacing of peaks agreed reasonably with that derived from the critical wave-number for the instability of a flat interface.

Type
Research Article
Copyright
© 1967 Cambridge University Press

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References

Brown, W. F. 1951 Amer. J. Phys. 5, 290.
Christopherson, D. G. 1940 Quart. J. Math. 11, 63.
Davies, J. T. & Rideal, E. K. 1963 Interfacial Phenomena. New York: Academic Press.
Landau, L. D. & Lifschitz, E. M. 1960 Electrodynamics of Continuous Media (transl. J. B. Sykes & J. S. Bell). Oxford: Pergamon Press.
Leslie, E. H. & Geniesse, J. C. 1933 International Critical Tables, 2, 136.
Melcher, J. R. 1963 Field Coupled Surface Waves. M.I.T. Press.
Neuringer, J. L. 1966 Int. J. Non-Linear Mech. 1, 123.
Rosensweig, R. E., Nestor, J. W. & Timmins, R. S. 1965 A.I.Ch.E.—I.Chem.E. Symposium Series 5, 104. London: Instn. Chem. Engrs.
Taylor, G. I. & Mcewan, A. D. 1965 J. Fluid Mech. 22, 1.