MHD Mixed Convection and Entropy Generation in a C-Shaped Enclosure Filled with an Electrically Conducting Fluid

Abstract

Magnetohydrodynamic (MHD) mixed convection and entropy generation in a C-shaped cavity filled by an electrically conducting fluid are investigated numerically using the finite volume method and the SIMPLE algorithm. In this work, we focus on the effect of the magnetic field on the characteristics of fluid flow, heat transfer and entropy generation for various values of Richardson number (Ri = 0.1, 1 and 10), Hartmann number (0 ≤ Ha ≤ 200), tilting angle (α); ranging from -45° to +45°, and aspect ratio (AR = 0.3, 0.5 and 0.7). The results show an increase in the average Nusselt number and the entropy generation by increasing the aspect ratio (AR), whereas they decrease when Ha number increases, independently of α and Ri. At high values of Ha number, the conduction state is the dominant mode of heat transfer regardless of Ri, AR and α. Moreover, the total entropy generation is mainly due to the irreversibility of heat transfer whatever the control parameters are.

Keywords

• Mixed convection
• C-shaped enclosure
• magneto-hydrodynamic
• electrically conducting fluid
• finite volume method

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