Pore‐level melting process of composite phase change material within different porous structure

Abstract Composites of phase change materials and porous media have been demonstrated as an efficient way to enhance thermal conductivity. To investigate the heat transfer process within the phase change material, a pore‐level composite phase change material model is established. The lattice structure of porous material can be idealized by hexahedral and Kelvin lattice structure. The Kelvin lattice structure demonstrates superior heat transfer performance and is employed to study the effect of porosity and pore density of the porous material on the melting process of the composite phase change material. The numerical results indicate that for a constant pore density, both the melting time and temperature response time of the composite phase change material decrease as porosity decreases. Similarly, for a fixed porosity, an increase in pore density leads to a reduction in melting time and temperature response time. Melting efficiency coefficient is introduced to evaluate the improvement in melting performance achieved by using porous material with different structural structures. Among all the structures examined, the Kelvin lattice structure with a porosity of 0.86 and a pore density of 20 pores per inch (PPI) exhibits the best heat transfer performance, achieving a complete melting time of 3.37 s, a temperature response time of 4.92 s, and a melting efficiency coefficient of 10.17.