Faculty Publications

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Author: search.filters.author.B.V., B.V.Subject: search.filters.subject.Heat transfer performance

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    Performance evaluation of novel tapered shell and tube cascaded latent heat thermal energy storage
    (Elsevier Ltd, 2021) B.V., B.V.; Nidhul, K.; Gumtapure, V.
    Geometric design of the storage system plays a vital role in the enhancement of heat transfer rate and thereby in the advancement of latent heat thermal energy storage (LHTES) technology. The present study numerically compares the heat transfer performance of tapered type shell and tube cascaded latent heat storage (CLHS) model with that of the conventional cylindrical CLHS model with special emphasis on melting rate at the slowest melting portions (bottom) of the shell and tube unit. Thermal properties like transition temperature, latent, and specific heat of the three organic PCMs OM 42, OM 46, and OM 48 have been obtained using differential scanning calorimetry (DSC), and the same is employed in the 2-D numerical simulation carried out using enthalpy-porosity method. Tapered CLHS unit exhibited superior performance owing to stronger natural convective currents demonstrated via streamlines, velocity, temperature and mass fraction contours. In tapered unit, 17.6% higher mean power is obtained for same volume of PCMs in cylindrical unit. In contrast, the mean power of the discharging process for a tapered type is 2.4% lesser than cylindrical type CLHS. The outcomes highlight that the tapered type CLHS model utilizes convective heat transfer, effectively enhancing the melting rate of PCM without any additional structural configurations such as fins. Hence is also economically justifiable for higher energy storage for the same volume compared to conventional cylindrical CLHS units. © 2020 International Solar Energy Society
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    Experimental investigation of melting and solidification characteristics in a vertical shell and tube latent heat thermal energy storage system with novel directional flow annular fins
    (Elsevier Ltd, 2025) Naik, L.; Gumtapure, V.; B.V., B.V.
    In this study the impact of novel directional flow annular fins on the charging and discharging process in a vertical shell and tube latent heat thermal energy storage system (LHTES) with phase change materials (PCM) is examined. Consequently, the tube carrying heat transfer fluid (HTF) is surrounded by five annular fins. To examine the impact of directional flow fins on the thermal performance of LHTES, four novel directional flow fin configurations namely, 1 mm thick solid circular fin, 10 mm thick hollow circular fin - flow of HTF only through the central tube, 10 mm thick hollow circular fin - flow of HTF partially through the central tube and partially through the fin structure, 10 mm hollow circular fin - flow of HTF only through the fin structure were selected. In order to study the LTHES experimentally, three sections are chosen for the location of thermocouples at 0, 120 and 240°. At each sections five thermocouples are located to record the temperature distribution in the PCM. A detailed behavior of melting and solidification cycles are explained by observing temperature variation, accumulative energy and melting fraction during both melting and solidification. Results show that use of directional flow fins decreases melting time by 58.33 % in comparison with conventional fins and solidification time by 50 % of LHTES and allows heat to penetrate deeper through the volume of the PCM more uniformly. Additionally, the thermal efficiency of the LHTES system was found to be 67.4 % during charging and 53.85 % during discharging, validating the significant improvement in energy storage and retrieval performance with directional flow fins in latent heat thermal energy storage system. © 2025