Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-19T07:47:06.906Z Has data issue: false hasContentIssue false

Stability of convection in a horizontal channel subjected to a longitudinal temperature gradient. Part 2. Effect of a magnetic field

Published online by Cambridge University Press:  10 September 2009

D. V. LYUBIMOV
Affiliation:
Perm State University, 15 Bukirev Street, 614990 Perm, Russia
T. P. LYUBIMOVA
Affiliation:
Institute of Continuous Media Mechanics UB RAS, 1 Koroleva Street, 614013 Perm, Russia
A. B. PERMINOV
Affiliation:
Perm State Technical University, 29a Komsomolsky Prospect, 614000 Perm, Russia
D. HENRY
Affiliation:
Université de Lyon, École Centrale de Lyon/Université Lyon 1/INSA de Lyon, Laboratoire de Mécanique des Fluides et d'Acoustique, UMR-CNRS 5509, 43 Bd du 11 Novembre 1918, 69622 Villeurbanne Cedex, France
H. BEN HADID*
Affiliation:
Université de Lyon, École Centrale de Lyon/Université Lyon 1/INSA de Lyon, Laboratoire de Mécanique des Fluides et d'Acoustique, UMR-CNRS 5509, 43 Bd du 11 Novembre 1918, 69622 Villeurbanne Cedex, France
*
Email address for correspondence: [email protected]

Abstract

The stabilization of buoyant flows by a magnetic field is an important matter for crystal growth applications. It is studied here when the cavity is an infinite channel with rectangular cross-section typical of horizontal Bridgman configurations and when the magnetic field is applied in the vertical and transverse directions. The steady basic flow solution is first calculated: the usual counter flow structure is modified by the magnetic field and evolves towards jets in the cross-section corners when the magnetic field is vertical and towards a more uniform structure in the transverse direction when the magnetic field is transverse. The stability results show a very good stabilization of the convective flows for a vertical magnetic field with exponential increases of the thresholds for any width of the channel and for various Prandtl numbers Pr. The results for a transverse magnetic field are more surprising as a destabilizing effect corresponding to an initial decrease of the thresholds is obtained at Pr=0 and for small channel widths. A kinetic energy budget at the thresholds reveals that the main destabilizing factor is connected to the vertical shear of the longitudinal basic flow and that it is the modifications affecting this shear energy which are mainly responsible for the variation of the thresholds when a magnetic field is applied.

Type
Papers
Copyright
Copyright © Cambridge University Press 2009

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

REFERENCES

Alboussière, T., Garandet, J. P. & Moreau, R. 1993 Buoyancy-driven convection with a uniform magnetic field. Part 1. Asymptotic analysis. J. Fluid Mech. 253, 545563.CrossRefGoogle Scholar
Alboussière, T., Garandet, J. P. & Moreau, R. 1996 Asymptotic analysis and symmetry in MHD convection. Phys. Fluids 8 (8), 22152226.CrossRefGoogle Scholar
Baumgartl, J., Hubert, A. & Müller, G. 1993 The use of magnetohydrodynamic effects to investigate fluid flow in electrically conducting melts. Phys. Fluids A 5 (12), 32803289.CrossRefGoogle Scholar
Baumgartl, J. & Müller, G. 1992 Calculation of the effects of magnetic field damping on fluid flow – comparison of magnetohydrodynamic models of different complexity. In Proceedings of the Eighth European Symposium on Materials and Fluid Sciences in Microgravity (ESA SP-333), pp. 161164. ESA Publication Division c/o ESTEC, Noordwijk, The Netherlands.Google Scholar
Ben Hadid, H. & Henry, D. 1994 Numerical simulation of convective three-dimensional flows in a horizontal Bridgman configuration under the action of a constant magnetic field. In Proceedings of the Second Intl Conf. on Energy Transfer in MagnetoHydroDynamic Flows, Aussois, France, vol. 1, pp. 4756. MHD Pamir Publications, Grenoble.Google Scholar
Ben Hadid, H. & Henry, D. 1996 Numerical simulations of convective three-dimensional flows in a horizontal cylinder under the action of a constant magnetic field. J. Cryst. Growth 166, 436445.CrossRefGoogle Scholar
Ben Hadid, H. & Henry, D. 1997 Numerical study of convection in the horizontal Bridgman configuration under the action of a constant magnetic field. Part 2. Three-dimensional flow. J. Fluid Mech. 333, 5783.CrossRefGoogle Scholar
Ben Hadid, H., Henry, D. & Kaddeche, S. 1997 a Numerical study of convection in the horizontal Bridgman configuration under the action of a constant magnetic field. Part 1. Two-dimensional flow. J. Fluid Mech. 333, 2356.CrossRefGoogle Scholar
Ben Hadid, H., Henry, D. & Touihri, R. 1997 b Unsteady three-dimensional buoyancy-driven convection in a circular cylindrical cavity and its damping by magnetic field. J. Cryst. Growth 180, 433441.CrossRefGoogle Scholar
Davoust, L., Cowley, M. D., Moreau, R. & Bolcato, R. 1999 Buoyancy-driven convection with a uniform magnetic field. Part 2. Experimental investigation. J. Fluid Mech. 400, 5990.CrossRefGoogle Scholar
Dold, P. & Benz, K. W. 1995 Convective temperature fluctuations in liquid gallium in dependence on static and rotating magnetic fields. Cryst. Res. Technol. 30 (8), 11351145.CrossRefGoogle Scholar
Dold, P. & Benz, K. W. 1997 Modification of fluid flow and heat transport in vertical Bridgman configurations by rotating magnetic fields. Cryst. Res. Technol. 32 (1), 5160.CrossRefGoogle Scholar
Garandet, J. P., Alboussière, T. & Moreau, R. 1992 Buoyancy-driven convection in a rectangular enclosure with a transverse magnetic field. Intl J. Heat Mass Transfer 35 (4), 741748.CrossRefGoogle Scholar
Henry, D., Ben Hadid, H., Kaddeche, S. & Dridi, W. 2008 b Magnetic stabilization of melt flows in horizontal Bridgman configurations. J. Cryst. Growth 310, 15331539.CrossRefGoogle Scholar
Henry, D., Juel, A., Ben Hadid, H. & Kaddeche, S. 2008 b Directional effect of a magnetic field on oscillatory low-Prandtl-number convection. Phys. Fluids 20, 034104(1–12).CrossRefGoogle Scholar
Hof, B., Juel, A. & Mullin, T. 2003 Magnetohydrodynamic damping of convective flows in molten gallium. J. Fluid Mech. 482, 163179.CrossRefGoogle Scholar
Hof, B., Juel, A. & Mullin, T. 2005 Magnetohydrodynamic damping of oscillations in low-Prandtl-number convection. J. Fluid Mech. 545, 193201.CrossRefGoogle Scholar
Hurle, D. T. J. 1993 Crystal Pulling From the Melt. Springer-Verlag.CrossRefGoogle Scholar
Hurle, D. T. J., Jakeman, E. & Johnson, C. P. 1974 Convective temperature oscillations in molten gallium. J. Fluid Mech. 64, 565576.CrossRefGoogle Scholar
Juel, A., Mullin, T., Ben Hadid, H. & Henry, D. 1999 Magnetohydrodynamic convection in molten gallium. J. Fluid Mech. 378, 97118.CrossRefGoogle Scholar
Kaddeche, S., Henry, D. & Ben Hadid, H. 2003 Magnetic stabilization of the buoyant convection between infinite horizontal walls with a horizontal temperature gradient. J. Fluid Mech. 480, 185216.CrossRefGoogle Scholar
Lyubimova, T. P., Lyubimov, D. V., Morozov, V. A., Scuridin, R. V., Ben Hadid, H. & Henry, D. 2008 Stability of convection in a horizontal channel subjected to a longitudinal temperature gradient. Part 1. Effect of aspect ratio and Prandtl number. J. Fluid Mech. 635, 275295.CrossRefGoogle Scholar
Moreau, R. 1990 Magnetohydrodynamics. Kluwer Academic.CrossRefGoogle Scholar
Okada, K. & Ozoe, H. 1992 Experimental heat transfer rates of natural convection of molten gallium suppressed under an external magnetic field in either the x-, y- or z-direction. ASME J. Heat Transfer 114, 107114.CrossRefGoogle Scholar
Ozoe, H. & Okada, K. 1989 The effect of the direction of the external magnetic field on the three-dimensional natural convection in a cubical enclosure. Intl J. Heat Mass Transfer 32, 19391954.CrossRefGoogle Scholar
Series, R. W. & Hurle, D. T. J. 1991 The use of magnetic field in semiconductor crystal growth. J. Cryst. Growth 113, 305327.CrossRefGoogle Scholar
Utech, H. P. & Flemings, M. C. 1966 Elimination of solute banding in Indium Antimonide crystals by growth in a magnetic field. J. Appl. Phys. 37 (5), 20212024.CrossRefGoogle Scholar