Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-19T03:02:18.789Z Has data issue: false hasContentIssue false

Anisotropic surface waves under a vertical electromagnetic force. Part 2. Experimental demonstration

Published online by Cambridge University Press:  29 March 2006

I. S. Robinson
Affiliation:
Institute of Oceanographic Sciences, Bidston Observatory, Birkenhead, Cheshire

Abstract

It was shown theoretically in part 1 (Shercliff 1969) that, when a horizontal magnetic field and electric current field are imposed upon a conducting liquid with a free surface, waves excited at the surface have an anisotropic dispersion relation. Here the possibility of demonstrating this phenomenon in the laboratory is considered. The analysis is completed for waves a t the interface between a conducting and non-conducting fluid of similar density, taking full account of surface tension, and then viscosity. Surface tension is found to have a considerable influence in reducing the degree of anisotropy to be expected. The problem of choosing suitable experimental parameters is discussed, and an apparatus is described in which it was possible to demonstrate the existence of anisotropic surface waves, and to compare the phase velocity with the theoretical results. Also, an experiment is described which verifies the relationship between the orientation of the anisotropy and the relative orientation of the imposed magnetic and current fields.

Type
Research Article
Copyright
© 1975 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Baker, R. C. 1965 Nature, 207, 65.
Duc, S. N. 1968 Etude théorique et experimentale sur modèle hydraulique des instabilities de Rayleigh-Taylor en magneto hydrodynamique. C.R. Acad. Sci. Paris, A 266, 738740.Google Scholar
Lamb, H. 1932 Hydrodynamics. Cambridge University Press.
Robinson, I. S. 1973 Anisotropic surface waves and instabilities under a vertical electro-magnetic force. Ph.D. thesis, University of Warwick.
Shercliff, J. A. 1969 Anisotropic surface waves under a vertical magnetic force. J. Fluid Mech., 38, 353Google Scholar
Shercliff, J. A. 1970 A note on the envelope construction for group velocity in dispersive anisotropic wave systems. J. Inst. Math. Appl., 6, 9195.Google Scholar