Amirkabir University of Technology Amirkabir Journal of Mechanical Engineering 2008-6032 53 1 2021 03 21 Effects of Magnetic Field on Natural Convection of Non-Newtonian Fluid in a Square Enclosure with a Central Heat Source Effects of Magnetic Field on Natural Convection of Non-Newtonian Fluid in a Square Enclosure with a Central Heat Source 259 278 3513 10.22060/mej.2019.16101.6274 FA Akram Jahanbakhshi Shahrekord University, Shahrekord Afshin Ahmadi Nadooshan Mechanical Engineering Department, Shahrekord University, Shahrekord 0000-0003-4345-9527 Journal Article 2019 04 09 In this study, the incompressible laminar flow of non-Newtonian fluid is studied in a cavity with a central heat source under a uniform inclined magnetic field. The governing equations are converted into nonlinear ordinary differential equations using similarity transformations and solved using finite difference based numerical methods. In the current study, the effect of non-Newtonian power-law fluid is investigated for power-law indices of 0.75, 1 and 1.4. The results are compared with the ones in which the magnetic field is not applied. It is found that the implementation of a magnetic field for different fluid indices in different Rayleigh numbers does not show similar behaviors and the results show that the magnetic field affects the convection flow, leading to a reduction in it. Also can be said that with the implementation of a magnetic field in the range of indices n ≥ 1 for power-law model fluid, increased Rayleigh number leads to reduced average Nusselt number and for n ˂ 1, the average Nusselt increases. For n ˂ 1, with increased Rayleigh number in the presence of a fixed magnetic field, free convection can be weakened while this trend for n ˂ 1 occurs with reduced Rayleigh number. In this study, the incompressible laminar flow of non-Newtonian fluid is studied in a cavity with a central heat source under a uniform inclined magnetic field. The governing equations are converted into nonlinear ordinary differential equations using similarity transformations and solved using finite difference based numerical methods. In the current study, the effect of non-Newtonian power-law fluid is investigated for power-law indices of 0.75, 1 and 1.4. The results are compared with the ones in which the magnetic field is not applied. It is found that the implementation of a magnetic field for different fluid indices in different Rayleigh numbers does not show similar behaviors and the results show that the magnetic field affects the convection flow, leading to a reduction in it. Also can be said that with the implementation of a magnetic field in the range of indices n ≥ 1 for power-law model fluid, increased Rayleigh number leads to reduced average Nusselt number and for n ˂ 1, the average Nusselt increases. For n ˂ 1, with increased Rayleigh number in the presence of a fixed magnetic field, free convection can be weakened while this trend for n ˂ 1 occurs with reduced Rayleigh number.

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