Experimental and numerical assessment of thermal characteristics of PCM in a U-shaped heat exchanger using porous metal foam and NanoPowder

Abstract

The utilization of Latent Heat Thermal Energy Storage (LHTES) has gained significant attention to address the disparity between energy supply and demand. One of the key advantages lies in the use of phase change materials (PCM). The purpose of this research is to overcome this obstacle by focusing on enhancing the thermal efficiency of an advanced thermal energy storage system specifically designed for solar domestic and industrial application. to overcome this obstacle by focusing on enhancing the thermal efficiency of an advanced thermal energy storage system specifically designed for solar domestic and industrial application. Through computational and experimental studies, a novel and small LHTES system with parallel U-shaped heat exchanger (USHX) has been created and investigated. To improve performance, two approaches are employed: optimizing thermal efficiency by dispersing nano-sized graphite powders into the paraffin material, and/or incorporating metal foams. The PCM is RT35HC, and the hot/cold heat transfer fluid is H₂O, which travels via the U-shaped tube. The model incorporates the enthalpy-porosity technique to account for phase change phenomena. After comparing the numerical outcomes with the experiments herein run, data are shown in terms of liquid fraction, temperature evolution, stored energy, and a dimensionless parameter that characterizes the phase change process. The findings suggest that the proposed methods for enhancing heat transfer can enhance the thermal efficiency of systems. The outcomes illustrate that by addition of all methods, reduces the melting time by 13.39 %, 60.77 %, and 71.93 %, when compared to system with pure PCM.