International Journal of Thermofluids最新文献

{"title":"Natural convection of water/Titanium oxide nanofluid inside a closed enclosure at different angles of attack","authors":"Laith S. Sabri ,&nbsp;Ali B.M. Ali ,&nbsp;Omid Ali Akbari ,&nbsp;Farnaz Montazerifar ,&nbsp;Faramarz Kahbandeh ,&nbsp;Soheil Salahshour ,&nbsp;A. Mokhtarian","doi":"10.1016/j.ijft.2025.101161","DOIUrl":"10.1016/j.ijft.2025.101161","url":null,"abstract":"<div><div>In most industrial applications, several situations are associated with closed enclosures, such as avionics, automotive, cooling/heating systems in buildings, electronic equipment, food, and phase change materials. In this paper, the natural convection (NC) of a Newtonian fluid inside a Non-Square Closed Enclosure (NSCE) is numerically simulated. The working fluid is a water/Titanium oxide nanofluid (NF) with volume fractions in the range of φ = 0 to 4 % and experiences a laminar flow with Rayleigh numbers (Ra) from 10³ to 10⁵. To benefit from better flow mixing, NSCE undergoes five different angles of attack -90°, -45°, 0°, 45°, and 90° degrees (cases 1 to 5, respectively). This research was solved using a computer code in two-dimensional space in steady state using the finite volume method. The solid-fluid suspension is considered homogeneous, single-phased, and Newtonian. The Boussinesq approximation is used for the density term. A SIMPLE algorithm is used for decoupling pressure and velocity fields. The results suggest that increasing the Ra number strengthens the fluid velocity components in the Closed Enclosure (CE). In all cases, the maximum Nusselt number (Nu) occurs at the interface between the fluid and the hot surface. In cases (1) and (5), due to the elongation of the fluid path, the circulation effects become more important, creating an anomaly in the friction factor for the <em>Ra</em> = 10⁵. A symmetric pattern in the Nu number diagrams in cases (2) and (4) is evident which is due to the invariance of this parameter in these two cases. Entropy generation is influenced by fluid circulation and rotation. In all cases and conditions, the use of solid nanoparticles reduces the temperature gradient, which significantly affects the removal of hot spots with high entropy and consequently reduces the average entropy generation. Increasing the angle of attack of the closed enclosure compared to the smooth case (case 3) at Rayleigh numbers 10³ and 10⁴ can increase the friction coefficient by a factor of 1.62. Also, at Rayleigh number 104, changes in the angle of attack of the closed enclosure will experience a decrease in the Nusselt number and average heat flux by &lt;8 % compared to the smooth case. At Rayleigh number 10³, the 10 % increase in the average Nusselt number and heat flux is only due to the increase in the volume fraction of the solid nanoparticle and is somewhat independent of the angle of attack of the closed enclosure.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101161"},"PeriodicalIF":0.0,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143680357","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":"Impact of hall current and rotational on MHD flow of nanofluid with joule heating and viscous dissipation","authors":"Guthula Kanaka Lakshmi,&nbsp;Paramsetti Sri Ramachandra Murty","doi":"10.1016/j.ijft.2025.101153","DOIUrl":"10.1016/j.ijft.2025.101153","url":null,"abstract":"<div><div>This study investigates the influence of Hall current, rotational effects, and thermal diffusion on the transient magnetohydrodynamic (MHD) free convection flow of water-based Cu and TiO₂ nanofluids, incorporating the effects of Joule heating and viscous dissipation. The fluid motion occurs along a permeable vertical plate under an applied magnetic field in a rotating frame of reference. The governing equations, formulated as partial differential equations (PDEs), are transformed into a system of ordinary differential equations (ODEs) using non-dimensionalization techniques and are solved analytically via the perturbation method. The study presents an in-depth analysis of velocity and temperature distributions, as well as the effects of key parameters such as the hall current, rotational force, thermal radiation and suction parameter. Results indicate that an increase in the Hall parameter enhances the velocity of the primary flow but decreases secondary velocity. The velocity profile also increases with higher thermal Grashof number, while a rise in the magnetic field strength retards fluid motion due to Lorentz force effects. The temperature profile decreases with increasing Prandtl number and heat source intensity. These findings provide valuable insights into the behavior of nanofluid flow in MHD environments and have potential applications in energy systems, cooling technologies, and electronic thermal management.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101153"},"PeriodicalIF":0.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143609329","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":"Investigating the combinations of operating parameters of PEMFC computational results using the Taguchi Method","authors":"Prem Kumar Thiyagarajan ,&nbsp;Nithesh Kumble Gokuldas ,&nbsp;Srinivasa G ,&nbsp;Avinash Kumar Rajendran ,&nbsp;Kavin Selvan Saravanakumar ,&nbsp;Mohanaharish Vasudevan ,&nbsp;Mohith Kannan ,&nbsp;C. Durga Prasad ,&nbsp;Adem Abdirkadir Aden","doi":"10.1016/j.ijft.2025.101162","DOIUrl":"10.1016/j.ijft.2025.101162","url":null,"abstract":"<div><div>Proton Exchange Membrane Fuel Cells (PEMFC) is considered a promising energy source due to higher energy efficiency, low pollution, fast startup time, and low operating temperature. Under simplified conditions of constant temperature and one-dimensional flow, through the channel, and zero-flux boundaries the model was solved. The model was validated using COMSOL Multiphysics software and experimental results with a 4.22 % and 5.5 % deviation. The Taguchi Method was used to study the operating parameters of PEMFCs and to identify optimal combinations for best output along with developing equations to predict maximum power density. The delta i.e. the difference between the mean of high- and low-level Signal to Noise (S/N) ratios was calculated and found that the relative humidity was significant with value 11.07. The optimum combination is found with the help of the S/N ratio graph based on the larger the better for the performance application. The maximum power density value was predicted using the equation and found to be deviated by 16.5 % with the help of an L8 orthogonal array. Modified Taguchi approach with L4 orthogonal array with a fixed level of higher derivation parameter, reduced the error deviation further to 6.5 % with respect to the simulation results. The approach will be handy for predicting the performance with fewer trials.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101162"},"PeriodicalIF":0.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576853","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":"Analysis and prediction of thermo-physical properties in water-based MWCNT-ZnO hybrid nanofluids using ANN and ANFIS models","authors":"Surendra D. Barewar ,&nbsp;Pritam S. Kalos ,&nbsp;Balaji Bakthavatchalam ,&nbsp;Mahesh Joshi ,&nbsp;Sarika Patil ,&nbsp;Mahesh Sonekar","doi":"10.1016/j.ijft.2025.101159","DOIUrl":"10.1016/j.ijft.2025.101159","url":null,"abstract":"<div><div>In this study, the thermal conductivity and viscosity of multiwalled-carbon nanotubes/zinc oxide water hybrid nanofluid across volume concentrations varying from 0.2 % to 0.8 % and temperatures from 25 °C to 65 °C were experimentally studied. Three mathematical models such as multivariable regression, artificial neural network, and adaptive neuro-fuzzy modeling were employed for the prediction of the thermal conductivity of the water baes multiwalled-carbon nanotubes/zinc oxide hybrid nanofluid. Volume concentration and temperature of the nanofluid are the input parameters for the models. Despite the complexity of the input data, which encompassed extensive ranges of temperature and volume concentration, adaptive neuro-fuzzy modeling exhibited superior predictive performance than the other two models. It achieved conductivity values closely aligned with experimental results, characterized by the lowest mean square error compared to regression and artificial neural network models. Notably, the adaptive neuro-fuzzy modeling method facilitated the resolution of the neural network layer's hidden structure without the need for extensive trial and error.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101159"},"PeriodicalIF":0.0,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576854","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":"AI-heat transfer analysis of casson fluid in uniformly heated enclosure with semi heated baffle","authors":"Khalil Ur Rehman ,&nbsp;Wasfi Shatanawi ,&nbsp;Lok Yian Yian","doi":"10.1016/j.ijft.2025.101148","DOIUrl":"10.1016/j.ijft.2025.101148","url":null,"abstract":"<div><div>The heat transfer in Casson fluid with natural convection claims various applications namely thermal regulation in biological systems, solar collectors, polymer processing, and geothermal applications to mention just a few. Owing to such motivation, we have offered artificial intelligence-based solution outcomes for heat transfer aspects in Casson fluid flow in a partially heated square enclosure with free convection effect. The semi-heated triangular baffle is installed at the center of the cavity. The bottom and right walls have the same amount of heat. The left wall of the cavity is taken cold and the top wall is taken insulated. The surface of triangular baffle and cavity walls are carried with non-slip condition. Finite element method (FEM) with hybrid meshing is used to solve the developed flow equations. AI-based neural networks model is used to examine the variation in Nusselt number for the involved flow parameters. MSE=2.15008e^-6, 5.81476e^-5, and 3.51888e^-4 for training, validation, and testing respectively, suggesting good model performance on Nusselt number data along the bottom and vertical walls. We have observed that the heat transfer coefficient improves as Rayleigh and Prandtl numbers increase. We believe that the present AI-based outcomes will be helpful for predicting natural convection phenomena subject to thermal engineering standpoints.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101148"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509099","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":"Bioconvective triple diffusion flow of micropolar nanofluid with suction effects and convective boundary conditions","authors":"Muhammad Bilal Riaz ,&nbsp;Kamel Al-Khaled ,&nbsp;Adnan ,&nbsp;Sami Ullah Khan ,&nbsp;Katta Ramesh","doi":"10.1016/j.ijft.2025.101138","DOIUrl":"10.1016/j.ijft.2025.101138","url":null,"abstract":"<div><div>This investigation reveals the triple diffusive bioconvective applications subject to micropolar nanofluid flow caused by oscillating stretched surface. The problem is subject to applications of radiative phenomenon and viscous dissipation features. In oscillating stretching surface, the porous medium and suction/injection features are considered. The modeling of flow problem is based on system of partial differential equations (PDE's). Such system is solved with implementation of homotopy analysis method (HAM). The convergence region is specified against HAM solution. Understanding of flow problem is observed by vary various flow parameters to evaluates the fluid velocity, micro-rotational velocity, temperature field, solutal concentration, nanoparticles concentration and microorganisms profile. The results for skin friction, Nusselt number, solutal Sherwood number, nano-Sherwood number and microorganism's density number are also presented. It has been observed that variation of velocity against time periodically oscillates and magnitude of oscillation declined due to porous parameter and suction/injection constant. The temperature profile enhances due to modified Dufour number and Eckert parameter. Moreover, the solutal concentration reduces due to regular Lewis number.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101138"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143561800","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":"Soret and nonuniform heat source/sink effects in micropolar nanofluid flow over an inclined stretching sheet","authors":"Machindranath Diwate ,&nbsp;Pradeep G. Janthe ,&nbsp;Nitiraj V. Kulkarni ,&nbsp;S. Sunitha ,&nbsp;Jagadish V. Tawade ,&nbsp;Nodira Nazarova ,&nbsp;Manish Gupta ,&nbsp;Nadia Batool","doi":"10.1016/j.ijft.2025.101160","DOIUrl":"10.1016/j.ijft.2025.101160","url":null,"abstract":"<div><div>This study investigates the heat and mass transfer dynamics of micropolar nanofluid flow over a stretching sheet subjected to nonuniform heat sources/sinks. The influence of key factors, such as Brownian motion, thermophoresis, chemical reactions, and thermal radiation, on the velocity, temperature, and concentration profiles of the nanofluid is explored. The research employs advanced numerical methods, using the <em>bvp4c</em> solver, to solve the governing equations and compute the effects of various physical parameters on fluid dynamics. The results demonstrate that an increase in the magnetic field strength reduces the fluid velocity, while changes in material properties can lead to higher fluid speeds. Furthermore, the Soret effect significantly enhances mass transfer and the heat transfer at the surface diminishes as <em>A*</em> and <em>B*</em> increases, with implications for applications in separation technologies and desalination. A detailed analysis of the influence of the Soret number, Brownian motion, and thermophoresis reveals critical insights into thermal transport and solute distribution in the boundary layer. These findings have practical applications in cooling systems, biomedical engineering, and other industries where precise control of heat and mass transfer is crucial.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101160"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636686","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":"Improving the thermal performance of a windcatcher employing cooling pipes with annular fins: Numerical evaluation","authors":"Habibollah Ranjbarvavdareh,&nbsp;Vahid Shokri,&nbsp;Yasser Rostamiyan","doi":"10.1016/j.ijft.2025.101110","DOIUrl":"10.1016/j.ijft.2025.101110","url":null,"abstract":"<div><div>To improve the thermal performance of a windcatcher, the current work employs three cooling pipes with radial fins as the heat transfer device (HTD) at its entrance. The proposed windcatcher's heat transfer and fluid flow are numerically investigated using commercial computational fluid dynamics software. The effects of geometric parameters of the used HTD, such as (i) the number of radial fins and (ii) the diameter of the radial fins, on the thermal performance of the proposed windcatcher are studied. The current study is unique in that it applies an efficient heat transfer enhancement technique—extended surfaces or fins—to windcatchers' HTD, which previous studies have not investigated. The examination of the effect of radial fins on the performance of the windcatcher, based on various fin diameters and numbers, shows that fins' presence and size significantly impact air velocity and temperature distribution within the system. Results depicted that using radial fins inside windcatchers improves airflow efficiency and thermal performance. The best configuration for airflow lies with the 220 mm fins, while the 300 mm fins show the best cooling effect. Accordingly, the inlet temperature of the models with 220 mm, 260 mm, and 300 mm fins is greater than the simple model (without fin case) by about 4.88 %, 5.69 %, and 8.13 %, respectively. Moreover, the inlet temperature of the models with three, four, and five fins is superior to the simple model by about 4.86 %, 6.88 %, and 8.1 %, respectively. These findings suggest that careful selection of fin size and number is critical for maximizing windcatchers' performance in terms of ventilation and cooling. The insights gained from these results can guide the design of more efficient windcatcher systems for sustainable building applications.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101110"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143561689","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":"Parametric enviro-economic analysis of cooling photovoltaic panels with phase change materials","authors":"Tarek Ibrahim ,&nbsp;Jalal Faraj ,&nbsp;Hicham El Hage ,&nbsp;Rani Taher ,&nbsp;Samer Ali ,&nbsp;Mahmoud Khaled","doi":"10.1016/j.ijft.2025.101151","DOIUrl":"10.1016/j.ijft.2025.101151","url":null,"abstract":"<div><div>This study conducts a parametric analysis to evaluate the effects of cooling PV panels using phase change materials (PCM), considering both economic and environmental aspects for two cases: a domestic house and a power plant. The study employs the consumption ratio (R), defined as the ratio between the actual energy consumption of a building and the maximum energy producible by the PV panels, as an indicator of energy use efficiency. Results show that the combined PCM-PV with heat sink (CPCM-PV-HS) system achieved the highest performance, with average energy production values of 634.35 × <em>R</em> kWh and 132,182.7 × <em>R</em> kWh for the domestic house and power plant, respectively. Corresponding economic savings were $272.77 × <em>R</em> and $56,838.57 × <em>R</em>, while reductions in CO₂ emissions averaged 367.92 × <em>R</em> kg and 76,665.97 × <em>R</em> kg The PV panel with PCM (PV-PCM) cooling method recorded the lowest values across all metrics. Additionally, a linear relationship was observed between efficiency enhancements and both savings and CO₂ reductions over the months of the year. This study underscores the potential of PCM-based cooling systems to improve PV panel performance, providing valuable insights for energy efficiency, cost savings, and environmental sustainability.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"27 ","pages":"Article 101151"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143548010","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":"Editorial: Advances in heat transfer science: Enhanced techniques for modern industrial applications","authors":"Ali Alahmer ,&nbsp;Ahmed Al-Manea ,&nbsp;Raed Al-Rbaihat ,&nbsp;Salman Ajib ,&nbsp;Khalid Saleh ,&nbsp;Adanta Dendy","doi":"10.1016/j.ijft.2025.101145","DOIUrl":"10.1016/j.ijft.2025.101145","url":null,"abstract":"<div><div>Heat transfer science plays a fundamental role in various industrial sectors, including energy generation, electronics cooling, and aerospace engineering. As industries advance, the need for more efficient, sustainable, and innovative heat transfer solutions becomes increasingly vital. This special issue, Advances in Heat Transfer Science: Enhanced Techniques for Modern Industrial Applications, presents cutting-edge research on innovative heat transfer solutions, focusing on nanofluids, phase change materials (PCMs), solar energy systems, heat exchangers, and computational modeling. Contributions highlight the use of nanofluids and hybrid nanofluids to enhance thermal performance in various geometries, the integration of PCMs for thermal energy storage, and the optimization of solar energy systems through advanced cooling techniques. Additionally, studies on heat exchangers, thermal management systems, and computational fluid dynamics (CFD) provide insights into geometric modifications, passive and active cooling methods, and numerical modeling for improved thermal performance. By exploring the interplay of magnetic fields, fluid dynamics, and geometric configurations, this issue offers a comprehensive overview of the latest advancements in heat transfer science, paving the way for more efficient, sustainable, and innovative industrial applications.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101145"},"PeriodicalIF":0.0,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143561690","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}