Faculty Publications
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Item Modified thermal energy storage unit for solar cookers using iterative design algorithm(Elsevier Ltd, 2022) Anilkumar, B.C.; Maniyeri, R.; Anish, S.The use of phase change materials (PCMs) as thermal energy storage (TES) mediums has gained notable attention in recent years due to their high energy density and constant temperature characteristics which makes them suitable for solar cookers (SCs). Therefore, the primary objective of this study is to develop a modified TES unit containing PCM as heat storage medium incorporated with cooking vessel for SCs. The TES units use PCM filled on all sides, including the lid, enhancing heat transfer to food load. The design of TES unit is carried out by developing computational procedure. MATLAB code is written to implement the iterative procedure, simplifying exhaustive calculations required for optimizing and designing the TES unit. The present work also aims to design, fabricate and test different geometries of TES units using paraffin wax as the PCM. After six hours, cooking load temperature in all geometries of TES units reached the melting point of PCM. TES units with cylindrical shapes perform best among hexagon and square designs. Through computational procedure, cylindrical configuration is the best as it takes least amount of PCM to keep steady temperature over a specific period. Based on the computational procedure developed in this study, TES container will be designed to enhance SC performance during sundown hours and maximize the use of latent heat stored within the PCM. © 2022Item Thermal performance assessment of a cylindrical box solar cooker fitted with decahedron outer reflector(SAGE Publications Inc., 2023) Anilkumar, B.C.; Maniyeri, R.; Anish, S.One of the important issues humankind globally faces in recent years is the scarcity of non-renewable energy resources. Solar energy is considered safe and renewable, which can fulfil the demand and supply chain requirements. Solar box cookers (SBCs) are popular in domestic cooking due to their ease of use and handling. The prime objective of the present work is to develop and test the performance of a cylindrical SBC fitted with decahedron-shaped reflector (CSBC-FDR). The CSBC is designed using minimum entropy generation (MEG) method. Through experiments, we observed that absorber plate attains peak temperature of about 138°C–150°C with the aid of decahedron reflector. The first figure of merit (F1) is found to be 0.13, indicating better optical efficiency and low heat loss coefficient for the SBC. The second figure of merit (F2) is obtained as 0.39, which indicates good heat exchange efficiency (F') and less heat capacity for cooker's interior. The average energy efficiency, exergy efficiency, and standardized cooking power values are 21.93%, 3.04%, and 25.28W, respectively. These results show that the present CSBC-FDR is able to cook food in a shorter period with better efficiency. The experimental and numerical values of overall heat loss coefficient of the developed SBC are in close agreement. The experimentally assessed performance parameters reveal superior performance of the present cylindrical SBC in comparison with many conventional rectangular and trapezoidal box solar cookers. © The Author(s) 2021.Item Design of thermal energy storage system for solar cooker: a review(Springer, 2025) Anilkumar, B.C.; Maniyeri, R.Solar cooking has been a research focus worldwide over the last few decades due to its numerous advantages, such as no running costs, non-polluting nature and ample availability. Solar cookers incorporate thermal energy storage (TES) units to enable cooking during off-sunshine hours. Within solar thermal applications, latent heat storage materials (LHSMs), particularly phase change materials (PCMs) are increasingly vital due to their superior energy storage density and isothermal working properties. The present review aims to provide a comprehensive overview of various TES unit designs integrated with cooking vessels for solar cookers. We discuss different types of solar cookers, various TES unit configurations, and the thermo-physical properties of heat storage materials. A key aspect of this work involves comparing the sizes of various TES units, derived from our previously developed computational scheme, with existing research. Prior studies often lacked specifics on the duration of off-sunshine cooking. However, determining the optimal PCM mass is crucial for designing efficient LHS units that maximize heat storage and release for sustained cooking. To address this gap, we employed a computational procedure to determine the duration for which various LHS units, integrated with box-type solar cookers, can maintain a constant cooking temperature. We also identified and compared the dimensions of containers needed to hold the optimum PCM mass. Our computational findings for the outer vessel diameter of LHS units align closely with previous studies. This computational approach offers a robust methodology for developing TES units that optimize PCM latent heat utilization, significantly enhancing solar cooker performance during sundown hours. Ultimately, we propose a pathway for improving future TES unit designs and present a strategy for marketing solar cookers. This review will be an invaluable resource for researchers, stimulating further advancements in solar cookers integrated with TES systems. © Indian Academy of Sciences 2025.