Faculty Publications
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Item Numerical Investigation on the Effect of Various Geometries in a Solar Box-Type Cooker: A Comparative Study(Springer Science and Business Media Deutschland GmbH, 2021) Anilkumar, B.C.; Maniyeri, R.; Anish, S.The solar energy as a renewable energy has been the primary interest of many researchers for the last four to five decades due to its wide applications such as domestic cooking systems. The present study aims to investigate the effect of various box geometries such as rectangular, trapezoidal, cylindrical and frustum of a cone on the performance of solar cookers. In this study, various heat losses (convective and radiative) from the cooker cavities are analysed by simulating the condition using commercial software ANSYS16. The results of numerical analysis of rectangular cavity box-type cooker are validated by comparing with experimental results. The results show that trapezoidal cavity box-type solar cooker has higher absorber plate temperature and minimum heat losses than all other geometries operating under the same conditions. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Item Performance Comparison of Different Geometries of Thermal Energy Storage Unit for Solar Cooker(Springer Science and Business Media Deutschland GmbH, 2023) Anilkumar, B.C.; Maniyeri, R.; Anish, S.Many researchers have been interested in solar energy as an unlimited energy resource over the last few decades due to its vast range of applications, including household cooking. The present work aims to design, optimize, fabricate, and test different geometries of thermal energy storage (TES) units for solar cooker (SC) using paraffin wax as the phase change material (PCM). The optimum amount of PCM necessary for different geometries (cylindrical, square, and hexagonal) of TES units surrounding the cooking vessel is computed using a computational approach. The TES units developed in this study have the provisions for filling the PCM on all sides, including the lid, enhancing the heat transfer to the cooking load. The performance comparison of different TES units is carried by conducting the indoor test. The experimental findings show that after 6 h, all geometries of TES units maintain the temperature of the cooking load at the melting point of PCM. However, cylindrical-shaped TES unit performs best in comparison with hexagonal and square. A cylindrical box solar cooker performance test is also carried out with an optimized cooking vessel surrounded by the PCM-filled TES unit and lid. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Item Performance Evaluation of Solar Cookers Using Multi-Criteria Decision-Making Methods(American Institute of Physics, 2024) Anilkumar, B.C.; Maniyeri, R.; Anish, S.The prime objective of the present study is to select the best solar cooker among the alternatives using multi-criteria decision-making (MCDM) methods. The criteria and alternatives for the analysis are taken from the previous study on solar cookers with different geometrical designs. It is difficult to identify the optimum from different alternatives by comparing the criteria values. In the present work, the optimum solar cooker is selected with the aid of technique for order preference by similarity to ideal solution (TOPSIS) and evaluation based on distance from average solution (EDAS) methods. The criteria weights required for the optimization algorithm are found by using ENTROPY and CRITIC methods. Also, TOPSIS and EDAS methods with equal criteria-weights are carried out. The optimization algorithms are solved using MATLAB. The results show that a novel solar box cooker (NSBC) with finned absorber plate performs best compared to a sun stove unit, conventional box-type, dish and trough type parabolic solar cooker. © 2024 American Institute of Physics Inc.. All rights reserved.Item Optimum selection of phase change material for solar box cooker integrated with thermal energy storage unit using multi-criteria decision-making technique(Elsevier Ltd, 2021) Anilkumar, B.C.; Maniyeri, R.; Anish, S.Various thermal energy storage (TES) materials are used to increase the efficacy of solar cooker in off-sun hours. For the past few decades, phase change materials (PCMs) used as heat storage medium have become research interest. Selection of optimum PCM is important for the effective and efficient heat storage. Therefore, the main objective of the current study is to select the optimum PCM among the alternatives to be used for TES unit incorporated in solar box cooker (SBC). The PCMs are pre-screened among the alternatives used in earlier works based on the melting temperature. The optimum PCM is then selected with the aid of different multi-criteria decision -making (MCDM) techniques like TOPSIS, EDAS and MOORA. The criteria weights required for the optimization algorithm is found by using AHP, ENTROPY and CRITIC methods. Also, compromised values between the weights obtained through these methods are computed. The optimization algorithms are solved using MATLAB. The results of all MCDM techniques show that erythritol is the best alternative for the TES medium incorporated in the SBC. Further, the optimum mass of PCM and dimensions of the TES unit required for the SBC to operate during sun down hours for some specific duration is calculated by using a simple iterative solver developed with MATLAB. There is good agreement between the computational procedure and experimental study using paraffin wax as the TES medium. The iterative solution procedure also selects erythritol to be the best alternative as it required lesser quantity compared with other PCMs. Therefore, we recommend erythritol as the best PCM for the SBC incorporated with TES unit. © 2021Item Design, fabrication and performance assessment of a solar cooker with optimum composition of heat storage materials(Springer Science and Business Media Deutschland GmbH, 2021) Anilkumar, B.C.; Maniyeri, R.; Anish, S.Solar energy as an inexhaustible source of energy has been the primary interest of many researchers for the last four to five decades due to its wide applications such as domestic cooking systems. The current work aims to determine the optimum cooker surface area with the aid of analytical heat loss and design equations. The top, bottom and side heat loss coefficients are calculated by an iterative procedure solved using MATLAB. Also, it seeks to obtain the performance parameters of a solar cooker having sensible heat storage materials. For an anticipated average solar irradiation of 800 W/m2 and for boiling 1.5 kg mass of water, the cooker surface area is found to be 0.36 m2 and fabricated accordingly. Also, in this study, iron grits, sand, brick powder and charcoal powder are taken in the optimum ratio (mass) of 1:2:2:3 respectively as heat storage material. The performance indicators namely first and second figures of merit (F1 and F2), thermal and exergy efficiency are found to be 0.085, 0.319, 16.1% and 0.61% respectively. It is found that water temperature in the developed thermal energy storage incorporated solar cooker is maintained above 70 °C until 6 PM in a day. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.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 Performance Prediction Model Development for Solar Box Cooker Using Computational and Machine Learning Techniques(American Society of Mechanical Engineers (ASME), 2023) Anilkumar, B.C.; Maniyeri, R.; Anish, S.The development of prediction models for solar thermal systems has been a research interest for many years. The present study focuses on developing a prediction model for solar box cookers (SBCs) through computational and machine learning (ML) approaches. The prime objective is to forecast cooking load temperatures of SBC through ML techniques such as random forest (RF), k-nearest neighbor (k-NN), linear regression (LR), and decision tree (DT). ML is a commonly used form of artificial intelligence, and it continues to be popular and attractive as it finds new applications every day. A numerical model based on thermal balance is used to generate the dataset for the ML algorithm considering different locations across the world. Experiments on the SBC in Indian weather conditions are conducted from January through March 2022 to validate the numerical model. The temperatures for different components obtained through numerical modeling agree with experimental values with less than 7% maximum error. Although all the developed models can predict the temperature of cooking load, the RF model outperformed the other models. The root-mean-square error (RMSE), determination coefficient (R2), mean absolute error (MAE), and mean square error (MSE) for the RF model are 2.14 (°C), 0.992, 1.45 (°C), and 4.58 (°C), respectively. The regression coefficients indicate that the RF model can accurately predict the thermal parameters of SBCs with great precision. This study will inspire researchers to explore the possibilities of ML prediction models for solar thermal conversion applications. © © 2023 by ASME.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.