Thermal instability of a rotating curved plate subjected to an applied magnetic field

Acta Mechanica - Tập 214 - Trang 343-356 - 2010
Chin-Tai Chen1
1Department of Industrial and Engineering Management, Ta-Hwa Institute of Technology, Hsinchu, Taiwan, Republic of China

Tóm tắt

The effect of a magnetic field on thermal instability in mixed convection flow on a heated rotating convex surface is studied in this paper. The onset position characterized by the Goertler number G δ depends on the Grashof number, the rotational number, the Prandtl number, the magnetic field parameter, and the wave number. The buoyancy force, the centrifugal force, the Lorentz force, and the Coriolis force are found to significantly affect the flow structure and heat transfer of the flow. Negative rotation (clockwise) destabilizes the boundary layer flow on a convex surface. However, the Lorentz force stabilizes the flow. Numerical data in this study show the same order of magnitude like experimental data.

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