A note on the similarity between the normal-field instability in ferrofluids and the thermocapillary instability

• Published in: Journal of fluid mechanics Vol. 583; pp. 459 - 464
• Main Author: JOO, SANG W.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 25.07.2007
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Ferrimagnetics; Fluid dynamics; Fluid mechanics; Free surfaces; Fundamental areas of phenomenology (including applications); Hydrodynamic stability; Magnetic fields; Magnetic properties and materials; Nonlinear equations; Physics; Studies of specific magnetic materials; Surface-tension-driven instability; Viscosity; Ferromagnetic fluid; Geometrical shape; Similarity; Drops; Magnetic field effects; Viscous fluids; Thermocapillarity
• ISSN: 0022-1120; 1469-7645
• DOI: 10.1017/S0022112007006726

A striking resemblance between the normal-field instability in ferromagnetic fluids and the interfacial mode of the thermocapillary instability in viscous fluids is presented. A nonlinear evolution equation describing the dynamics of the free surface for a ferrofluid layer subject to a uniform normal magnetic field is derived, and compared to that for a thin viscous layer heated from below. Their similarity predicts the possibility of mutual nonlinear stability control.