The interfacial stability of a ferromagnetic fluid
- 22 December 1967
- journal article
- research article
- Published by Cambridge University Press (CUP) in Journal of Fluid Mechanics
- Vol. 30 (4) , 671-688
- https://doi.org/10.1017/s0022112067001697
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.Keywords
This publication has 3 references indexed in Scilit:
- Some viscous flows of a saturated ferro-fluid under the combined influence of thermal and magnetic field gradientsInternational Journal of Non-Linear Mechanics, 1966
- The stability of a horizontal fluid interface in a vertical electric fieldJournal of Fluid Mechanics, 1965
- Electric and Magnetic Forces: A Direct Calculation. IAmerican Journal of Physics, 1951