Molecular Simulations of Adsorption and Thermal Energy Storage of Mixed R1234ze/UIO-66 Nanoparticle Nanofluid

Abstract

In the process of adsorption and separation of fluid molecules on the solid surface of porous nanomaterials, the mutual transformation of thermal energy and surface energy can improve the heat absorption and energy utilization efficiency of circulating working medium. In this study, the adsorption, thermal energy storage, and mean square displacement of the minimum energy adsorption configuration of R1234ze in UIO-66 were studied by molecular simulations, including molecular dynamics (MD) and grand canonical Monte Carlo (GCMC) simulations. The results show that the thermal energy storage density of R1234ze/UIO-66 mixed working medium is significantly higher than that of pure working medium in the temperature range of 20 K-140 K. However, the increase rate of thermal energy storage density decreases significantly as temperature rises, and the mean square displacement and diffusion coefficient increase with increasing temperature.