International Journal of Thermofluids最新文献

{"title":"Thermodynamic and thermoeconomic aspects of utilizing two distinct solar collectors in a multigeneration system","authors":"Eman Shakir Hussein Hussein,&nbsp;Iraj Mirzaee,&nbsp;Samrand Rash-Ahmadi,&nbsp;Morteza Khalilian","doi":"10.1016/j.ijft.2025.101182","DOIUrl":"10.1016/j.ijft.2025.101182","url":null,"abstract":"<div><div>This thesis delves into the thermodynamic and exergoeconomic analysis of a multigeneration system that utilizes solar and geothermal energy to generate electricity, cooling, heating, hydrogen, and fresh water. The system's design comprises a solar collector, geothermal energy, an organic Rankine cycle, a double-effect lithium-bromide absorption refrigeration cycle, a domestic water heater, a proton exchange membrane electrolyzer, and a reverse osmosis desalination unit. Therminol VP1 nanofluid mixed with AL₂O₃ is utilized in the solar collector. The EES software was used to perform all the analyses. The research is centered on factors such as the concentration of nanoparticle volume, the temperature at the inlet of the solar collector, solar radiation, and the figure of merit of TEG. A comparison of PTC, ETC collectors indicates that the PTC collector demonstrates superior performance. The utilization of the PTC collector resulted in system energy and exergy efficiencies of 22.39 % and 15.11 %, respectively. Additionally, integrating the TEG unit will lead to a 50 % increase in power production by the system. In addition, the system can generate 56.6 kilograms of hydrogen per day and 1.47 kilograms of freshwater per second.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101182"},"PeriodicalIF":0.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143698118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vehicle platooning of DrivAer model at different flow regimes: Effect on aerodynamic forces","authors":"Moath N. Zaareer ,&nbsp;Abdel-Hamid I. Mourad","doi":"10.1016/j.ijft.2025.101181","DOIUrl":"10.1016/j.ijft.2025.101181","url":null,"abstract":"<div><div>Vehicle platooning, where vehicles travel in close proximity to reduce aerodynamic drag and improve efficiency, is increasingly feasible with advances in autonomous driving technologies. This study examines the aerodynamic forces acting on two and three vehicles in series at different spacings, corresponding to the extended-body, reattachment, and co-shedding regimes. Results reveal a 50.6 % reduction in drag coefficient for the front vehicle and a 65 % increase in downforce for the rear vehicle in the extended-body regime. These findings highlight significant potential for decreasing drag effect and stability in platooning scenarios. A similar trend is observed for three vehicles, with the first and second vehicles having the lowest drag coefficients and the third vehicle experiencing the highest downforce.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101181"},"PeriodicalIF":0.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143680356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impacts of magnetic and buoyancy forces on mixed convection nanofluid flow in an inclined exhaust geometry considering the KKL correlation and thermal radiation","authors":"Meysam Atashafrooz ,&nbsp;Amin Amiri Delouei ,&nbsp;Hasan Sajjadi ,&nbsp;Wei-Mon Yan ,&nbsp;Elham Sadat Behineh","doi":"10.1016/j.ijft.2025.101183","DOIUrl":"10.1016/j.ijft.2025.101183","url":null,"abstract":"<div><div>The main goal of this research is to examine the interacting impacts of buoyancy force, thermal radiation, nanoparticles concentration and magnetic force on thermal behaviors of mixed convection alumina-water nanofluid flow in an inclined Exhaust geometry. This geometry includes two inclined forward facing steps (FFSs) which are symmetrically located on the top and bottom walls of an inclined channel. These inclined steps are modeled in Cartesian coordinates by applying the embedded boundary method. The governing equations are numerically solved by means of the finite volume method and SIMPLE algorithm. The Rosseland approximation is adopted to calculate the radiative heat transfer term in the energy equation. Influences of Brownian motion on the effective thermal conductivity and viscosity of nanofluid is considered by applying the KKL correlation. The results are shown for various values of Grashof number (Gr = 0 − 30, 000), the Exhaust inclination angle (γ = 0° − 90°), radiation parameter (Rp = 0 − 1), Hartmann number (Ha = 0 − 200) and alumina nanoparticles concentration (ξ = 0 − 0.04). The predicted results indicate that the Gr,  γ,  Rp and Ha parameters have a considerable impact on the temperature distributions inside the bottom half domain of the Exhaust, whilst the influence of ξ parameter on these distributions is very small and ignorable. Furthermore, the maximum value of total heat transfer rate happens in the vertical Exhaust with highest values of Gr,  Rp,  Ha and ξ parameters (γ = 90°,  Gr = 30, 000,  Rp = 1,  Ha = 200,  ξ = 0.04). Comparing the numerical results of the present study with the results of other benchmark problems shows excellent agreement.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101183"},"PeriodicalIF":0.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling distillate output of a solar distiller with eco-friendly wood-based steam generation basin using machine learning model and starling murmuration optimizer","authors":"Mohammed Azmi Al-Betar ,&nbsp;Otto L. Muskens ,&nbsp;Karrar A. Hammoodi ,&nbsp;Mohamed Abd Elaziz ,&nbsp;Qusai Yousef Shambour ,&nbsp;Salam Fraihat ,&nbsp;Ammar H. Elsheikh","doi":"10.1016/j.ijft.2025.101179","DOIUrl":"10.1016/j.ijft.2025.101179","url":null,"abstract":"<div><div>Yield augmentation of solar distiller (SD) using low-cost modifications with minimum environmental impacts is highly desirable. In this study, we developed an eco-friendly steam generation device made of carbonized Ficus sycomorus wood to boost the yield of the conventional single-basin solar distiller. Moreover, a hybrid model composed of a long short-term memory (LSTM) network and a Starling murmuration optimizer (SMO) was developed to predict the yield of the established SD. To verify the accuracy of the model, three other models were employed and the distillate yield was predicted. The predicted data of all models was evaluated using different error measures. These models were standalone LSTM and LSTM optimized by an artificial hummingbird algorithm (AHA) or manta ray foraging optimizer (MRFO). Real field data were employed during the training and testing of all models. The thermal performance of the distiller with the steam generation device was compared with that of a traditional distiller based on exergy output, exergy efficiency, and energy efficiency. The distillate yield, exergy efficiency, and energy efficiency of the modified SD were enhanced by 34 %, 49 %, and 40 %, respectively, compared with that of the traditional distiller. Moreover, the total amount of produced drinkable water using the modified SD could reach a high value of 6.1 L/day with a low cost of 0.014 $/L.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101179"},"PeriodicalIF":0.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A sequential technique for solving the inverse problem associated with the assessment of time-dependent surface heat flux in a porous fin","authors":"M. Baghban ,&nbsp;Z. Shams ,&nbsp;S.H. Pourhoseini","doi":"10.1016/j.ijft.2025.101173","DOIUrl":"10.1016/j.ijft.2025.101173","url":null,"abstract":"<div><div>In this research, an inverse algorithm utilizing the sequential method is implemented to estimate the unknown time-dependent base heat flux in a porous fin, based on temperature readings collected from within the medium. The direct problem is resolved using the finite difference method to ascertain the temperature distribution. To illustrate the effectiveness of the inverse method in estimating the unknown base heat flux, two particular cases are analyzed. The study investigates how the number of future time points, measurement inaccuracies, and sensor locations affect the inverse solution. The results confirm that the inverse method can achieve accurate and stable estimations of the time-dependent base heat flux, even when measurement errors are present. It is observed that, for achieving an accurate heat flux estimation, the sensor location should be positioned as close to the base of the fin as possible. The findings reveal that an increase in the porosity parameter results in a diminished accuracy of heat flux estimation.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101173"},"PeriodicalIF":0.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143698117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lignocellulosic biomass conversion to levulinic acid via acid catalysis: Current methods, opportunities and challenges for self-sustaining biorefineries","authors":"George Hurst ,&nbsp;Aron Teklemariam ,&nbsp;Sean Brierley ,&nbsp;Mayri Alejandra Diaz De Rienzo ,&nbsp;Silvia Tedesco","doi":"10.1016/j.ijft.2025.101175","DOIUrl":"10.1016/j.ijft.2025.101175","url":null,"abstract":"<div><div>In recent years, integrated biorefineries have received growing interest as to maximise the extractable value from biomass in the form of green platform chemicals in order to support the establishment of a low carbon economy. Research and development in this area has focused on the conversion of lignocellulosic biomass, regarded as second-generation feedstocks, into a multitude of biochemicals from numerous different plant-based feedstocks with a wide range of catalytic systems, particularly the production of levulinic acid. This work critically reviews the most significant and pertinent literature of the methods and challenges of second-generation feedstock for levulinic acid production, identifying heterogeneous/homogeneous catalyst synergies can improve yields between 28 and 58 % depending on mineral catalyst promoter used. In addition, areas of particular focus of this review regards solid residues potential applications in a circular biorefinery context, revealing the novel role of hydrochar as booster additive in anaerobic digestion, which results in increased methane yields and, potentially, better soil amending digestate. The review also highlights the gaps in knowledge and synthesise new concepts to bridge these gaps in research, most pertinently applied to the solid residue formation and properties, with key links between multiple fields defined for the first time.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101175"},"PeriodicalIF":0.0,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing proton exchange membrane electrolyzer cells: A comprehensive parametric analysis of flow, electrochemical, and geometrical factors","authors":"Ali Bayat ,&nbsp;Prodip K. Das ,&nbsp;Goutam Saha ,&nbsp;Suvash C. Saha","doi":"10.1016/j.ijft.2025.101177","DOIUrl":"10.1016/j.ijft.2025.101177","url":null,"abstract":"<div><div>This study presents a comprehensive parametric study to optimise the performance of Proton Exchange Membrane Electrolyzer Cells (PEMECs). By systematically analyzing the effects of flow, electrochemical, and geometrical parameters, key factors that influence PEMEC efficiency and hydrogen production rates are identified. Utilizing single-phase numerical modeling in a three-dimensional approach with COMSOL Multiphysics, the study simulates the water electrolysis process, considering both free and porous media fluid flow along with detailed electrochemical reactions. The numerical simulation thoroughly explains the interplay between fluid mechanics and electrochemical phenomena within the PEMEC. The results show significant concordance with existing experimental data and predictions made by Eulerian two-phase modeling for the fluid flow field. Key findings include the analysis of polarization plots, the impact of operating temperature, membrane thickness, and conductivity on these plots, and species molar distribution. Additionally, a local sensitivity analysis highlights the relative importance of each parameter. Our findings provide valuable insights to enhance PEMEC design and operational strategies, particularly for applications in renewable energy storage and industrial hydrogen production. The identified optimizations, such as thinner membranes and higher conductivity materials, can contribute to higher efficiency, reduced energy consumption, and lower operational costs, making PEMEC technology more viable for large-scale deployment. By leveraging advanced numerical simulation techniques, this study offers a robust framework for optimizing PEMEC performance and supports the development of more efficient and sustainable hydrogen production technologies.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101177"},"PeriodicalIF":0.0,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A hybrid CRITIC-MAIRCA framework for optimal phase change material selection in solar distillation systems","authors":"Akashdeep Negi ,&nbsp;Lalit Ranakoti ,&nbsp;Vedant Singh ,&nbsp;Prabhakar Bhandari ,&nbsp;Meizi Wang ,&nbsp;Gusztáv Fekete ,&nbsp;Tej Singh","doi":"10.1016/j.ijft.2025.101167","DOIUrl":"10.1016/j.ijft.2025.101167","url":null,"abstract":"<div><div>Phase change materials (PCMs) serve as an efficient thermal energy storage mediums across a range of thermal systems, including solar distillations. The selection of an appropriate PCM candidate is a vital integration aspect that affects solar distillation performance. Therefore, the present research introduces a multi-criteria decision-making (MCDM) framework for identifying suitable PCM candidates for application in solar distillation systems. Evaluation indices include eighteen PCM alternatives and seven criteria, which were established from the literature. Criteria importance through intercriteria correlation (CRITIC) method was used to assign objective weights to the criteria, followed by the MAIRCA (multi-attributive ideal-real comparative analysis) approach to rank PCM alternatives. The proposed MCDM model suggests the suitability of paraffin wax followed by soy wax and beeswax PCMs for solar distillation applications, respectively. The comparative analysis, sensitivity analysis, and Kendall rank correlation effectively validated the rankings, demonstrating a robust positive correlation among the results. This study can serve as a preliminary step for experimental and simulation-based investigations aimed at optimizing the selection of PCM in the early stage, thereby reducing the time and costs associated with further analysis.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101167"},"PeriodicalIF":0.0,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143680361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pressure drop study of two-phase flows under condensation within capillary tubes","authors":"K. G. Domiciano ,&nbsp;M. B. H. Mantelli ,&nbsp;M. Mameli ,&nbsp;S. Filippeschi","doi":"10.1016/j.ijft.2025.101169","DOIUrl":"10.1016/j.ijft.2025.101169","url":null,"abstract":"<div><div>In the present study, an experimental investigation of pressure drops in two-phase flows within capillary tubes operating at low mass flow rates under condensation conditions was conducted. The primary objective was to understand the mechanics driving such flows to support the design of condensers for small two-phase devices, such as miniature loop heat pipes. A simple yet innovative experimental setup was developed, wherein the flows, similar to those in heat pipe technologies, were passively induced by vapor pressure. Pressure drops in two-phase flows under diabatic conditions were measured. Water and ethanol were tested, with mass flow rates below 6 × 10⁻⁵ kg/s and mass fluxes ranging from 15.5 to 209.3 kg/m²s. Copper and high-quality PVC capillary tubes with diameters between 0.446 mm and 1.010 mm were employed. Under diabatic conditions, the vapor entered the tubes with an initial vapor quality of one and condensed as it traveled through the tubes, leaving with vapor qualities between approximately 70 % and 90 %. In some cases, the condensed liquid coalesced into large plugs that completely filled the tube's cross-section, leading to confined flow conditions. These liquid plugs required higher vapor pressures to be pumped along the tube. Consequently, the pressure drop behavior was highly dependent on the flow regime. Lower pressure drops were observed when the vapor flowed at high velocities, causing the liquid to disperse into small droplets. Conversely, higher pressure drops occurred when the condensate formed blockages within the tube. The pressure drops in the flow ranged from 958 Pa to 75.4 kPa for water and 524 Pa to 59.8 kPa for ethanol. These values were consistently between the single-phase vapor and liquid pressure drops, typically closer to the latter. Notably, the observed pressure drops were significantly lower than those predicted by conventional literature correlations for two-phase flows. Furthermore, the study discusses the critical roles of pressure drops induced by fluid phase changes and the influence of capillary forces due to the confined liquid flows.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101169"},"PeriodicalIF":0.0,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artificial neural network analysis on heat and mass transfer in MHD Carreau ternary hybrid nanofluid flow across a vertical cylinder: A numerical computation","authors":"Shilpa ,&nbsp;Ruchika Mehta ,&nbsp;K. Senthilvadivu","doi":"10.1016/j.ijft.2025.101171","DOIUrl":"10.1016/j.ijft.2025.101171","url":null,"abstract":"<div><div>The objective of this study is to examine the combined impact of MHD non-Newtonian Carreau ternary nanofluid flow with mass and heat transport through a vertical stretching cylinder associated with a chemical reaction and radiation parameter. The main aim of this study is to increase the thermal efficiency using three different categories of nanoparticles: copper (<em>Cu</em>), aluminium oxide (<em>Al₂O₃</em>), and titanium dioxide (<em>TiO₂</em>), with H₂O serving as the original fluid is calculated. Applying similarity transformation, partial differential equations can be transformed into ordinary differential equations which are nonlinear, and simplified numerically using the bvp4c technique in the MATLAB software. This work provides new information about the behaviour of heat plumes under magnetic fields, thermal radiation and flow, and has potential applications in enhancing cooling systems in industrial applications, modelling of oil reservoirs and nuclear waste storage. Nanoparticles are used for cooling processors, cancer therapy, medicine, metal strips, automobile engines, welding equipment, fusion reactions, chemical reactions, and for cooling heat exchange mechanisms in various engineering devices due to their superior thermo physical properties. The novel characteristics of a variety of physical parameters on velocity, temperature, concentration, skin friction coefficient, and Nusselt number and mass transfer rate are discussed via graphs, charts, and tables. Results of this investigation indicate that the temperature of modified nanofluids decreased through the increasing amounts of radiation (0.5≤ Nr≤ 20.5), prandtl number (6.2≤ Pr≤ 21) and heat source (0.1≤ Q≤ 0.9) while the opposite impression for the volume fraction of Al₂O₃ (0.05≤ <span><math><mrow><msub><mi>ϕ</mi><mrow><mi>A</mi><msub><mi>l</mi><mn>2</mn></msub><msub><mi>O</mi><mn>3</mn></msub></mrow></msub><mo>≤</mo></mrow></math></span> 0.30) nanoparticles. The skin friction rate and Nusselt number rises as the Weissenberg parameter (0.1≤ We≤ 1.3) enhances. The nanoparticles concentration decays when the Schmidt number (0.1≤ Sc≤ 0.9) and chemical reaction (0.1≤ Kr≤ 0.5) are increased. The results in this limited scenario are consistent with previously published studies. Moreover, neural networking model is constructed to enhance the accuracy of predicting kinetic energy values. The comparison of numerical values and ANN predicted values are displayed through graphs, which are in good agreement.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101171"},"PeriodicalIF":0.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}