Review on numerical simulations for nano-enhanced phase change material (NEPCM) phase change process

Abstract

A review on numerical simulations performed for solidification and melting process of nano-enhanced phase change materials (NEPCM) is reported. The studies were conducted to understand the factors influencing the process such as nanoparticle fraction in the mixture, nanoparticle size and shape, boundary conditions imposed and container and fin geometry. Then, common nanoparticles applied in the studies were highlighted. The numerical models applied to simulate the problems were next presented. Finally, the thermophysical properties predicted and applied in the numerical works were compared. It was found that copper was the most applied nanoparticle in the numerical simulations. Most researchers applied enthalpy-porosity formulation coupled with finite volume method to perform the simulations. This method was preferred because it is relatively simpler compared to multidomain approach and mesoscale methods. Regardless of the chosen method, most researchers used a single thermophysical property value for the NEPCM in both solid and liquid regions. Brinkman and Maxwell correlations were mostly used to approximate the dynamic viscosity and thermal conductivity of the NEPCM, respectively. It is essential to understand the limitations and to select the most suitable thermophysical properties correlation to be applied in the numerical simulations to ensure that the final results will be acceptable and deviation from experimental works is effectively suppressed.