Synthesis and characterization of myristic acid - infused Al2O3/CuO/MWCNT nanocomposites for energy storage and cooling applications

Abstract

Phase change materials are highly effective in improving the thermal efficiency of a heat exchanger, making them a choice for enhancing renewable energy to achieve a feasible environment. In this study, myristic acid (MA) was used as a phase change material and aluminium oxide (Al2O3), copper oxide (CuO) of 2.5, 5, 10 wt % and multi-walled carbon nanotubes (MWCNT) of 1.0, 1.5, and 2 wt % were used as the nanoparticles to produce MA-embedded nanocomposite phase change material (NCPCM). The characterization studies, namely x-ray diffraction, Thermal Conductivity, field emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Differential Scanning Calorimetry (DSC) and Thermogravimetric analysis (TGA) were performed on nanocomposite phase change materials to ensure their homogeneous distribution and property enhancement of the fabricated samples. In addition, a Computational Fluid Dynamics (CFD) analysis was conducted to assess the impact of NCPCM on the rates of solidification and melting. The field emission scanning electron microscopy analysis confirms the homogeneous distribution of micro/nanoparticles Al2O3, CuO, and MWCNT with MA. From the x-ray diffraction (XRD) analysis, the homogeneous nature of the fabricated NCPCMs was identified. Fourier transform infrared spectroscopy (FTIR) and Raman Spectroscopy results confirmed the absence of new particle formation due to the physical interaction between nanocomposites and myristic acid. The fabricated NCPCM samples were undergone 500 thermal cycles to ensure their thermal reliability. It is evident from the test results that the addition of nanoparticles to base PCM enhances the thermal properties. The thermal performance of 2 wt% MWCNT-embedded MA was superior to that of aluminium oxide and copper oxide. DSC results revealed that the 2 wt% MWCNT added MA possessed the highest variation of 8.6% in its latent heat storage value compared to pure MA and had a significant variation compared to other fabricated NCPCM compositions. Adding 2 wt% MWCNT to MA has increased the thermal conductivity of pure PCM from 0.15 W mK−1 to 0.38 W mK−1.