• Energy Research

Abstract In this work, the thermal performance of graphene reinforced paraffin wax phase change material (GrPW-PCM) for thermal energy storage applications has been investigated. Though a stability test for the confirmation of uniform dispersion of graphene in paraffin wax environment is conducted but scanning electron microscopy (SEM), Fourier transform infrared spectra scope (FTIR) and thermal conductivity are also applied to characterize the microstructure, chemical structure and thermal properties. Four different samples of GrPW-NC phase change material (PCM) are prepared with a low mass fraction of graphene varied from 0.0 to 2.0 wt.%. However, the best performance with regards to thermal conductivity is given by 2.0 wt.% GrPW-PCM nanocomposites, which has been improved 66.15% when compared with pure paraffin PCM.

Abstract In this work, the thermal performance of graphene reinforced paraffin wax phase change material (GrPW-PCM) for thermal energy storage applications has been investigated. Though a stability test for the confirmation of uniform dispersion of graphene in paraffin wax environment is conducted but scanning electron microscopy (SEM), Fourier transform infrared spectra scope (FTIR) and thermal conductivity are also applied to characterize the microstructure, chemical structure and thermal properties. Four different samples of GrPW-NC phase change material (PCM) are prepared with a low mass fraction of graphene varied from 0.0 to 2.0 wt.%. However, the best performance with regards to thermal conductivity is given by 2.0 wt.% GrPW-PCM nanocomposites, which has been improved 66.15% when compared with pure paraffin PCM.

Abstract Dispersion of conducting polymer-based nanocomposite in Phase Change Materials (PCMs) tends to enhance the thermophysical properties. Present work aims to synthesize and disperse conducting polyaniline@cobalt nanocomposite within the Paraffin matrix to improve the thermo-physical property. Polyaniline based nanocomposites with 1.0 and 2.0 wt% cobalt (PC1 and PC2) were sonicated with paraffin at different weight ratio of 0.1%, 0.5%, 1%, and 5% and characterization of nanocomposite dispersed phase change material was performed. Thermo-physical properties were analysed by using thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC). Thermal conductivity of nanocomposite enhanced paraffin increased with increase in weight% of both PC1 and PC2 till 1% of its weight in paraffin and decreased for 5% of PC1 and PC2 concentration with paraffin. TGA readings observed drop in initial decomposition temperature of PPC1-5% (Paraffin with PC1 in 5% concentration) and PPC2-5% (Paraffin with PC2 in 5% concentration) by an amount of 08% and 12.4% respectively compared with base PCM Paraffin wax. DSC results of PPC1-0.1% and PPC2-0.5% showed 182.04 J/g and 170.86 J/g latent heat of fusion as compared to Paraffin wax. The samples were tested for 200 thermal cycles and the chemical stability and thermal property were compared with the fresh samples.

Abstract Dispersion of conducting polymer-based nanocomposite in Phase Change Materials (PCMs) tends to enhance the thermophysical properties. Present work aims to synthesize and disperse conducting polyaniline@cobalt nanocomposite within the Paraffin matrix to improve the thermo-physical property. Polyaniline based nanocomposites with 1.0 and 2.0 wt% cobalt (PC1 and PC2) were sonicated with paraffin at different weight ratio of 0.1%, 0.5%, 1%, and 5% and characterization of nanocomposite dispersed phase change material was performed. Thermo-physical properties were analysed by using thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC). Thermal conductivity of nanocomposite enhanced paraffin increased with increase in weight% of both PC1 and PC2 till 1% of its weight in paraffin and decreased for 5% of PC1 and PC2 concentration with paraffin. TGA readings observed drop in initial decomposition temperature of PPC1-5% (Paraffin with PC1 in 5% concentration) and PPC2-5% (Paraffin with PC2 in 5% concentration) by an amount of 08% and 12.4% respectively compared with base PCM Paraffin wax. DSC results of PPC1-0.1% and PPC2-0.5% showed 182.04 J/g and 170.86 J/g latent heat of fusion as compared to Paraffin wax. The samples were tested for 200 thermal cycles and the chemical stability and thermal property were compared with the fresh samples.

Vertical PCM enclosures are widely used in different applications. The weak heat conduction in these systems is their main deficiency. In present work, the “L” shaped fin was utilized instead of ordinary double rectangular fins. 10 different cases were considered which included two typical arrangements. First arrangement, included the fins placed at the lower side of the enclosure and the second arrangement was for the fins placed at the upper side of the enclosure. Furthermore, dimensions of vertical part (LV) and horizontal (LH) were considered as the varying parameters. The left vertical wall was heated and has constant temperature of 343 K. Luaric acid was used as PCM material. The results indicated that the orientation and dimensions of the “L” shaped fins have significant effect on the melting performance, energy storage and exergy of the enclosure. It was found that the application of upward L shaped fin is better than the upward form in the melting process of a vertical enclosure. The best case was related to fin mounted at the lower side of the enclosure which had LH and LV of 40 and 20 mm, presenting about 45% enhancement in the melting time.