EFFECT OF THERMALLY ACTIVE ZONES AND DIRECTION OF MAGNETIC FIELD ON HYDROMAGNETIC CONVECTION IN AN ENCLOSURE

Abstract

The aim of the present numerical study is to investigate the effect of thermally active zones and direction of the external magnetic field on hydromagnetic convection in an enclosure. Nine different relative positions of the thermally active zones are considered. Top and bottom of the enclosure are adiabatic. The governing equations are solved by the finite volume method. The results are obtained for different directions of the external magnetic field, thermally active locations, Hartmann numbers, Grashof numbers and aspect ratios. It is observed that the heat transfer is enhanced for heating location is either at middle or at bottom of the hot wall while the cooling location is either at top or at middle of the cold wall. The flow field is altered when changing the direction of the magnetic field in the presence of strong magnetic field. The average Nusselt number decreases with an increase of the Hartmann number and increases with increase of the Grashof number and aspect ratio.

Dates

  • Submission Date2010-02-10
  • Revision Date2011-02-01
  • Acceptance Date2011-10-06

DOI Reference

10.2298/TSCI100221094S

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