Convective heat transfer enhancement and entropy generation analysis for radiative flow of ferrofluid inside the enclosure with non-uniform magnetic field

Abstract

The present work consists of investigating the thermal performance and entropy generation for the non-isothermal radiative-convective flow of magnetic-ferrofluid inside the cavity exposed to the variable magnetic field. The effects of Lorentz and Kelvin forces for magnetized liquid are associated with magnetohydrodynamic (MHD) and ferrohydrodynamic (FHD) are examined during this study. The penalty method is used to eliminate pressure terms from governing nonlinear system of partial differential equations, and then Galerkin finite element is utilized to reduce the system into a system of algebraic equations, which is then solved with the help of Newton Raphson method to obtain the required (unique) solution. The obtained results show that the thermal mixing and entropy generation increases with an increase in the magnetic number Mnf. The concentration of ferroparticles volume fraction (ϕ) from 0 to 0.05 increases the heat transfer rate by 62.78% and decreases the total entropy generation by 57.3%. The maximum 93.62% augmentation in the heat exchange rate is obtained at ϕ=0.05 and Mnf=103. The results of the present work can be used in obtaining geometric parameters and optimizing designs for effective energy transfer in chemical reactors, solar collectors, nuclear magnetic resonance imaging, heat exchangers, and dye removal from textile wastewater.