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The cylinder wake in a magnetic field aligned with the velocity

Published online by Cambridge University Press:  26 April 2006

Abstract

We investigate experimentally the up- and downstream flow around an insulating cylinder in a conducting fluid subjected to an aligned magnetic field for low values of the magnetic Reynolds number Rm. For high values of the Alfvén number α = B0/U0(ρμ0)½ the upstream flow is characterized by magnetic and kinematic wakes. In this configuration we have measured, for the first time, the local values of the induced magnetic field. The results were analysed in a confined situation and show that the Oseen number k = ½Rm(1-α2) is the main parameter that characterizes the perturbation. In the downstream flow the two fields of perturbations (magnetic and kinetic) are characterized by von Kármán eddies. Our experiments were focused on the evolution of these eddies and show in particular that the critical Reynolds number increases strongly with the intensity of the magnetic field.

Type
Research Article
Copyright
© 1993 Cambridge University Press

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References

Ahlstrom, M. G. 1963 Experiments on the upstream wake in magneto-fluid dynamics. J. Fluid Mech. 15, 205222.Google Scholar
Alemany, A., Moreau, R., Sulem, P. L. & Frisch, U. 1979 Influence of an external magnetic field on homogeneous M.H.D. turbulence. J. Méc. 18, 277313.Google Scholar
Borisov, B. P. & Krasilnikove, J. 1981 Experimental determination of the condition for unseparated flow behind a cylinder in a longitudinal magnetic field. Proc. Riga Sem. on MHD, pp. 5758 (in Russian.)Google Scholar
Caperan, Ph. & Alemany, A. 1985 Turbulence homogène MHD à faible nombre de Reynolds magnétiques. Etude de la transition vers la phase quasi bidimensionalle et caractérisation de son anisotropie. J. Méc. Théror. Appl. 4, 175200.Google Scholar
Cristoloveanu, S. 1981 Transport magnétoélectrique dans les semi-conducteurs en présence d'inhomogénéités naturelles ou induites par effet de recombinaison et d'injection. Application aux capteurs magnétiques. Doctorat d'Etat. Université Scientifique et Médicale de Grenoble et Institut National Polytechnique de Grenoble.
Golubjev, A. V., Kaschulin, A. P., Krasilnikove, J. & Luschik, W. G. 1984 Flow of liquid metal around a cylinder in a longitudinal magnetic field. Proc. MHD Conf. Riga, pp. 9598 (in Russian.)
Horlock, J. H. 1963 Some two-dimensional magneto-fluid dynamic flow at low magnetic Reynolds number. J. Fluid Mech. 16, 1733.Google Scholar
Josserand, J., Marty, Ph. & Alemany, A. 1993 Pressure and drag measurements on a cylinder in a liquid metal flow with an aligned magnetic field. Fluid Dyn. Res. 11, 107117.Google Scholar
Lahjomri, J. 1988 Caractérisation de la structure de sillages M.H.D. amont et aval d'un cylindre à petit nombre de Reynolds magnétiques. Thèse de l'Université Joseph Fourier-Grenoble 1.
Lake, B. M. 1971 Velocity measurements in region of upstream influence of a body in aligned-fields MHD flow. J. Fluid Mech. 50, 209231.Google Scholar
Maxworthy, T. 1962 Measurements of drag and wake structure in magneto fluid dynamic flow about a sphere. Proc. Heat Trans. Fluid Mech. Inst. Seattle, WA, June 13–15, 1962, pp. 197204. Stanford University Press.
Maxworthy, T. 1968 Experimental studies in magneto-fluid dynamics: pressure distribution measurements around a sphere. J. Fluid Mech. 31, 801814.Google Scholar
Maxworthy, T. 1969 Experimental studies in magneto-fluid dynamics: flow over a sphere with cylindrical after body. J. Fluid Mech. 35, 411416.Google Scholar
Roshko, A. 1954 On the development of the turbulent wakes from vortex streets. Natl Adv. Comm. Aero., WA Rep. 1197.Google Scholar
Shercliff, J. A. 1965 A Textbook of Magnetohydrodynamics. Pergamon.
Tamada, K. 1962 Flow of slightly conducting fluid past a circular cylinder with strong aligned magnetic field. Phys. Fluids 5, 817823.Google Scholar
Yonas, G. 1967 Measurements of drag in a conducting fluid with an aligned field and large interaction parameter. J. Fluid Mech. 30, 813821.Google Scholar
Yosinobu, H. 1960 A linearized theory of magnetodynamic flow past a fixed body in parallel magnetic field. J. Phys. Soc. Japan 15, 175188.Google Scholar