Faculty Publications

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  • Item
    Characterization of linear low-density polyethylene with graphene as thermal energy storage material
    (Institute of Physics Publishing helen.craven@iop.org, 2019) Chavan, S.; Gumtapure, V.; Arumuga Perumal, D.A.
    In this work authors reported the preparation and characterization of composite phase change material (CPCM) using the direct-synthesis method by blending the Linear low-density polyethylene (LLDPE) with Carboxyl Functionalized Graphene (f-Gr). LLDPE is selected as base material and f-Gr is dispersed into three different concentrations 1.0, 3.0, and 5.0 wt% and referred as CPCM-1, CPCM-2 and CPCM-3 respectively. Experimental analysis is carried out through Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and Differential scanning calorimeter (DSC). The preset study assesses the influences of nanoparticle concentration on thermophysical properties, thermal performance and thermal storage characteristics of CPCMs. Results show that addition of f-Gr improves the thermal conductivity and latent heat of fusion of LLDPE. However, f-Gr slightly reduces the melting temperature and decreased the crystallization temperature. Therefore, this study reveals that f-Gr, addition to LLDPE has substantial potential for improving the thermal energy storage performance. © 2019 IOP Publishing Ltd.
  • Item
    Numerical and experimental analysis on thermal energy storage of polyethylene/functionalized graphene composite phase change materials
    (Elsevier Ltd, 2020) Chavan, S.; Gumtapure, V.; Arumuga Perumal, A.P.
    The main driving force behind the present work is environmental issues caused due to the usage of plastics, and energy issues. Current work attempts to address these problems by converting recycled plastics into thermal storage materials (TSM). Unfavorable thermophysical properties of plastic make it impractical but these inadequacies can be amended by blending with additives of superior thermophysical properties like, functionalized graphene. Numerical and experimental analysis are carried out to assess the thermal performance of TSMs (LLDPE, CPCM-1, CPCM-2 and CPCM-3) and check the compatibility of the materials. The phase change temperature of TSM is 123 to 125 °C and heat of fusion is 71.95 to 97 kJ/kg. Several thermal characteristics are analyzed to assess thermal performance and the amount of heat energy supplied, rate of heat transfer, and heat storage efficiency are deliberated. Results shown energy level enhancement of 43.17, 50.42, 54 and 50.61% for LLDPE, CPCM-1, CPCM-2 and CPCM-3 respectively. Among the TSM CPCM-2 shows relatively better storage capability (54% enhancement) due to incorporation of optimum concentration of enhancing material. The solidification process takes place through convection and radiation mode of heat transfer, at the completion of solidification process the TSM energy content reduces to 97.5, 96, 96 and 96% for LLDPE, CPCM-1,CPCM-2 and CPCM-3 respectively. This work concludes that, recycled plastics can be blended and it can be converted into efficient thermal storage material. © 2019 Elsevier Ltd
  • Item
    Computational investigation on the effect of geometrical parameters on thermal energy storage systems
    (Begell House Inc., 2021) Chavan, S.; Gumtapure, V.; Arumuga Perumal, D.
    The present work is an attempt to understand the effect of geometry on the heating and cooling characteristics of thermal energy storage systems. Three different geometrical models (square, pentagon, and hexagon) were considered and the thermal storage material used was a composite of paraffin wax (98%) and Al2O3 nanoparticles (2%). The heating and cooling processes were analyzed by applying a constant heat flux. Among the three models, the square model showed a faster melting rate but the cooling rate was too steep. The hexagonal model showed optimum results in both the heating and cooling processes with uniform and smooth variations in the liquid fraction and temperature. Hence, for optimal thermal storage applications the hexagonal model (or its geometries), which is close to the circular model, can be considered. © 2021 by Begell House, Inc.
  • Item
    Performance assessment of composite phase change materials for thermal energy storage-characterization and simulation studies
    (Bentham Science Publishers, 2021) Chavan, S.; Gumtapure, V.; Arumuga Perumal, D.
    Background: The present study mainly focuses on the development of new Thermal Storage Materials (TSM) and compare the performance for thermal energy storage capacity. Linear Low-Density Polyethylene (LLDPE) based Composite Phase Change Materials (CPCMs) is prepared, and its properties are analyzed using characterization, analytical calculations, and numerical simulation meth-ods. The composites are prepared by blending the functionalized graphene nanoparticles (1, 3 & 5%) with three different concentrations into LLDPE. All three CPCMs show enhanced thermal performance compared to the base material, but it is noticed that higher concentrations of nanoparticles increase the dynamic viscosity and produce an adverse effect on thermal performance. Thermal characterization shows improved latent heat capacity with nanoparticle concentration, analytical and numerical results also compared, which shown a difference of 10 to 25%. Objective: The purpose of this study is the development and evaluation of the thermal storage capacity of different thermal storage materials and enlighten the techniques used for characterizing the storage materials. Methods: Composite material preparation is carried out by using twin-screw extruders, characterization of developed material is done through FTIR, SEM, and DSC analysis. For complete analysis character-ization, analytical calculations and numerical simulation methods are used. Results: Linear low-density polyethylene-based composite materials can be successfully developed using a twin-screw extruder. This extrusion provided proper dispersion of nanoparticles into the base material, and it is validated by SEM analysis. DSC analysis confirmed the enhancement in the thermo-physical properties of composite materials. Conclusion: The latent heat capacity increased around 20% during the heating cycle and reduced ap-proximately 23% during the cooling cycle for base material and 5% addition of nanoparticle, respec-tively. The comprehensive study accomplishes that the optimum concentration of nanoparticle provides better thermal performance for thermal energy storage applications. © 2021 Bentham Science Publishers.