Entropy and hydrothermal analyses of nano-encapsulated phase change materials within a U-shaped enclosure: Impact of diverse structures of baffles and corrugated wall

Abstract

The entropy and hydrothermal inspections of natural convection (NC) flow and heat transfer (HT) within cavities may absorb a raft of researchers' attention owing to their significant industrial applications in the electronic devices' cooling, solar collectors, heat exchangers, micro-electro-mechanical systems, etc. Based on this requirement of efficient and long-time cooling, internal baffles, encapsulation of phase change material (PCM) by nanoparticle (NEPCM), internal corrugated hot triangular wavy wall are considered in this examination to ameliorate HT into PCM, thereby HT increment speeds up the rate of PCM melting and reduces the operating period for PCM-based thermic management. The present study investigates the NC of magnetic NEPCMs within a U-shaped enclosure with the bottom as a triangular wavy corrugated wall (subject to stable heat flux due to sunlight transmitted from a PTSC's reflector) and comprised of two cold baffles of variable length. The FEM is the numerical approach to achieving the desired solution. The results are that growth of Hartmann number results in the reduction of streamlines, isotherms, and horizontal and vertical velocities. Ascent of baffle length (l) yields amelioration of the local HT rate while the height of corrugated wall exhibits a reverse effect with/without magnetic field impact.