Numerical Investigation on Heat Transfer Characteristics of Microencapsulated Phase Change Material Slurry in a Rectangular Minichannel

Microencapsulation phase change material slurry (MEPCMS) becomes a potential working fluid for cooling high energy density miniaturized components, thanks to the latent heat absorption of particles in the heat transfer process. In this work, the Discrete Phase Model (DPM) based on the Euler-Lagrangian method is used to numerically investigate the convective heat transfer characteristics of MEPCMS flowing through a rectangular minichannel with constant heat flux. The results show that particles of MEPCMS are mainly subjected to drag force during the flow. Even so, they can migrate from the high-temperature region to the low-temperature region driven by the thermophoretic force, affecting the particle distribution and phase change process. Moreover, the Nu x of the MEPCMS fluctuates due to particle phase change with varying specific heat capacities. Specifically, the value increases first, then decreases, and eventually increases again until it approaches the fully developed value of the pure base fluid as the particles gradually melt. Furthermore, the heat transfer performance of the MEPCMS is influenced by the combination of fluid inlet temperature ( T in ), fluid inlet velocity ( v ), and mass concentration ( c m ) of MEPCM particles. The result shows that the maximum reduction of the maximum bottom wall temperature difference (Δ T w ) is 23.98% at T in =293.15 K, v =0.15 m·s −1 , c m =10%.