Faculty Publications
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Item Phase change materials in chemical and process engineering(Elsevier, 2023) Chavan, S.; Manickam, M.; Arumuga Perumal, A.P.; Gumtapure, V.This chapter is concerned with phase change materials in chemical and process engineering. Industrial waste heat recovery is explored as a source of heating and cooling with the application of phase change materials, which is well known. Consequently, heat transformation technologies are presented in detail along with their technical and economic potentials. Initially, utilization of phase change materials in process industries is discussed, which covers on-site and off-site industrial applications. The concept of on-site and off-site thermal energy utilization is well defined. The large amount of industrial waste heat is generated, which can be stored in the phase change materials, and it can be transported to the place where there is energy requirement in particular. Industries such as metal manufacturing, nonmetal manufacturing, chemicals and chemical products, pulp, and food processing industries are the main focuses of the present study. All the technical aspects are discussed in detail with respect to the future scope of phase change materials with thermal energy storage systems. Thermal energy utilization using phase change materials for chemical process industries also has great potentiality for various applications such as thermal fluid heating systems, gas-fired systems, and solar heating systems, which are also discussed. A comprehensive study has been carried out for potential usage of phase change materials for various manufacturing and process engineering applications. © 2023 Elsevier Ltd. All rights reserved.Item Cooling packing and cold energy storage(Elsevier, 2023) Chavan, S.; Manickam, M.; Arumuga Perumal, A.P.; Gumtapure, V.This chapter is divided into two parts: first part discusses about cooling packing applications of phase change materials, and second part discusses about cold thermal energy storage application of PCM. Consequently, methods of thermal energy storage are briefly explained, specifically for cooling packing applications along with present challenges of the technology. The second part of the chapter discusses in brief about cold thermal energy storage specifically basic working principle, loading of cold thermal energy storage for operational purposes CTES in selecting and characterizing storage media, water versus ice thermal energy storage, PCM used for cold thermal storage, advantages, disadvantages, and finally, battery thermal management system in electric vehicle are discussed in brief with updated knowledge in the field of real-time application. © 2023 Elsevier Ltd. All rights reserved.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 Computational investigation of bounded domain with different orientations using CPCM(Elsevier Ltd, 2019) Chavan, S.; Gumtapure, V.; Arumuga Perumal, D.A.The present work deals with the composite phase change material (CPCM) of 98% paraffin wax and 2% copper nanoparticle, filled into the bounded domain. Effects of orientation (45° 90° 135° and 180°) with different wall heating conditions (base, left and top wall) are analyzed numerically to understand the flow patterns and interface morphology developed during melting/solidification processes. The melting/solidification mechanism exhibited non-uniform flow patterns and irregular morphology which are dependent on geometrical orientations and different wall heating conditions. The results revealed that the bounded domain with different orientations have significant effect on natural convection current formation. As the orientation changes, the heat transfer rate gets influenced significantly and convection currents amplifies. Top wall heating arrangement of 180° orientation shows competence in achieving better thermal performance. © 2019 Elsevier LtdItem Thermal property study of fatty acid mixture as bio-phase change material for solar thermal energy storage usage in domestic hot water application(Elsevier Ltd, 2019) B.V., R.M.; Gumtapure, V.For the correct design, simulation and specific application of the latent heat thermal energy storage (LHTES) system, detailed evaluation of phase change material (PCM) properties are essential. Present study aims to analyze the thermal and volume dependent behavior of available organic Bio-PCM OM55, using conventional thermal gravimetric analyzer (TGA), thermal constant analyzer (TCA), differential scanning calorimeter (DSC) and in-house T-history method (THM). Execution of the mentioned thermal analysis outcome with significant information of OM55. TGA shows that OM55 is thermally stable within the operating temperature 45–60 °C, because the maximum permissible degradation temperature 154.6 °C is much higher than operating temperature range. The OM55 has considerable thermal conductivity compared to the existing PCM, which is already used in domestic solar water heating (DSWH) applications. The evaluation of transition temperature, isothermal enthalpy, and specific heat by THM are well compared with the DSC analysis. Comparison of DSC and THM analysis showed that the behavior of OM55 is volume independent. The overall study concluded that OM55 is a potential Bio-PCM. However, for the optimum amount of energy storage and discharge in OM55, it is recommended to operate the LHTES unit over a temperature range between 46–59 °C for domestic hot water application. © 2019 Elsevier LtdItem 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 LtdItem Thermo-physical analysis of natural shellac wax as novel bio-phase change material for thermal energy storage applications(Elsevier Ltd, 2020) B.V., B.V.; Gumtapure, V.The high energy density of latent heat storage makes it more competent than other types of thermal energy storage (TES) systems. Studying thermophysical and rheological properties of phase change material (PCM) is required for effective storage design, simulation, and applications. Bio-based PCM (BPCM) is a renewable and eco-friendly option for commercial paraffin-based PCMs. This study intends to characterize the shellac wax using the conventional and non-conventional approach as novel BPCM. Analysis of Fourier transforms infrared spectrophotometer (FTIR) indicates that shellac wax has aliphatic hydrocarbons, carboxylic acid, alcohol, and esters functional group. Thermogravimetric analysis (TGA) shows shellac wax has no mass change for operating temperature range (50–85 °C). Differential scanning calorimetry (DSC) analysis reported enthalpy of melting and crystallization as 148 kJ/kg and 161 kJ/kg, respectively. The crystallization enthalpy measured in the T-history method (THM) is 210.5 kJ/kg. However, DSC analysis of sample undergone 0,100,200 and 300 thermal cycle shows no significant change in thermal properties. Other properties like thermal conductivity, density, specific heat and viscosity are comparable to the present PCM used in storage applications. The overall study outcome that shellac wax is thermally stable and is potential BPCM for the TES application like solar desalination, district heating, waste heat recovery and solar cooking. © 2020 Elsevier LtdItem 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.Item Experimental investigation of shellac wax as potential bio-phase change material for medium temperature solar thermal energy storage applications(Elsevier Ltd, 2022) B.V., B.V.; Thanaiah, K.; Gumtapure, V.Thermal performance of shellac wax as a novel bio-phase change material (BPCM) and Therminol®-55 as heat transfer fluid (HTF) in a vertical shell and tube latent heat thermal energy storage (LHTES) unit is analyzed experimentally. Operational parameters considered, namely HTF flow rate and inlet temperature in the range of 2–5 LPM and 100–120 °C, respectively. The comprehensive study of contours and plots reveals the impact of natural convection and the progress of the melting and solidification front in the charging and discharging process. As the HTF flow rate increases, the charging rate improves considerably, and a maximum reduction in melting time is obtained as 43.6% for 4 LPM. The maximum reduction in melting time and storage efficiency are 42.2% and 73.4%, respectively, at 120 °C and 4 LPM. However, the discharging process's increased flow rate has no significant effect on solidification and discharge efficiency, which attributes the dominant mode of heat transfer is conduction during the solidification. Shellac wax storage efficiency is comparable to existing paraffin wax, stearic acid and palmitic acid-based LHTES unit. In this regard, shellac wax can be a potential Bio-PCM for medium temperature range (60–80 °C) solar thermal applications such as domestic water heating and food drying. © 2021 International Solar Energy SocietyItem T-HISTORY ANALYSIS OF ASPECT RATIO EFFECT ON SUBCOOLING AND SOLIDIFICATION BEHAVIOUR OF PHASE CHANGE MATERIAL IN VERTICAL GLASS TUBES(Serbian Society of Heat Transfer Engineers, 2022) Rudra, M.B.V.; Gumtapure, V.The study deals with the effect of the tube aspect ratio on subcooling and the solidification behaviour of phase change material using the T-history method and is compared with the differential scanning calorimetry analysis. Three tubes of different aspect ratios, l/d, and a constant length of 178 mm are chosen for this study. Infrared contour depicts that the inner surface of the glass tube and phase change materia initiate heterogeneous nucleation. The differential scanning calorimetry heat flow graph indicates a higher degree of subcooling than T-history method. The study of aspect ratio with and without insulation shows that the mean value of degree of subcooling is less in the insulated tube than non-insulated tube due to reduced cooling rate. The effect of the high aspect ratio is to increase the degree of subcooling due to increased cooling rate and, however, decrease the sensible heat discharge time to reach the plateau, tplt. © 2022 Society of Thermal Engineers of Serbia. All Rights Reserved.