Thermal analysis on a nanofluid-filled rectangular cavity with heated fins of different geometries under magnetic field effects

Rectangular cavity filled with a non-Newtonian shear-thinning nanofluid was investigated considering varied fin geometry under a vertical magnetic field. Irreversibility and entropy generation mechanisms were investigated by finite element method. The effect of geometry parameter (a), Hartmann number (Ha), nanoparticles volume fraction (φ) and nanoparticles type (Fe₃O₄, CuO and Al₂O₃) on the Nusselt numbers, entropy generations and Bejan numbers were investigated by the response surface methodology (RSM). Increasing a leads to an increase in both local and average Nusselt numbers and increment in different terms of entropy generation, while it reduces the Bejan number. Fe₃O₄ nanoparticle shows the highest Nusselt number compared to other nanoparticles. RSM analysis revealed that a = 0.29 and φ = 0.04 are the optimized values for the goal of maximum Nusselt number and minimum Bejan number.