Synthesis, Characterization and Computational Fluid Dynamics Analysis of Nano-Enhanced Phase Change Materials for Thermal Energy Storage Systems /

Abstract

The paradigm shift of energy markets from conventional energy sources to renewable energy sources of production has created an increased demand for the creation of efficient energy storage systems to overcome the sustainability challenges. To increase the overall efficiency of thermal energy storage systems, the performance and capabilities of different Phase Change Materials are studied. Fatty acids-based Phase change materials (PCMs) are regarded as one of the most promising candidates to store and release large amounts of latent heat, but they offer low thermal conductivity cause to limits its applications. Nano-enhanced fatty acid-based phase change materials were prepared in different concentrations (1 to 5%) by utilizing a two-step methodology which includes combining mechanical agitation and ultrasonic vibration. Thermal conductivity mater (DTC) used to determine the thermal conductivities of PCMs and NEPCMs. The chemical structure characterization and thermal stability of NEPCMs were performed using Fourier Transformation Infrared Spectroscopy (FT-IR) and Thermal Gravimetric Analysis (TGA) respectively. The thermal characteristics of charging and discharging processes and thermos-physical properties were studied using the T-history method and Differential Scanning Colorimetry (DSC). The T-History method is a cheap and reliable method than DSC. The results obtained from the T-History Method are compared with literature and DSC. A good agreement is found. The experimental results yielded by utilizing both the techniques showed that the thermal conductivity of the NEPCMs was effectively enhanced alternately. From the findings, it can be concluded that MA-Al2O3-1 is a promising candidate for heat transfer performance enhancement of fatty acids. The thermal performance of PCMs and fabricated NEPCMs that filled in different geometries concerning aspect ratio and angular orientation were also investigated numerically using enthalpy-porosity-based numerical coding formulations. The findings revealed that the best performance is provided by the MA-Al2O3-1 filled X / Y=0.15 case with 90 design that showed 83.02% thermal efficiency.