International Journal of Thermofluids最新文献

{"title":"Lumped parameter modeling and experimental characterization of pressure effects in a roller-type peristaltic pump with neoprene tubing for dialysis machines.","authors":"Carlo Carotenuto ,&nbsp;Federico Ferrari ,&nbsp;Stefano Salerno ,&nbsp;Federico Bernabei ,&nbsp;Wassim Lababidi ,&nbsp;Luca Montorsi ,&nbsp;Massimo Milani","doi":"10.1016/j.ijft.2025.101132","DOIUrl":"10.1016/j.ijft.2025.101132","url":null,"abstract":"<div><div>Dialysis machines are vital devices for individuals with chronic kidney diseases, functioning as artificial kidneys to purify blood by removing waste and excess fluid. At the core of these machines are volumetric pumps, with peristaltic pumps being particularly essential for their high precision and gentle handling of sterile fluids such as blood.</div><div>This study focuses on the experimental characterization of a four-roller peristaltic pump with a neoprene tube, analyzing its volumetric efficiency under varying suction (Pin) and discharge (Pout) pressures, motor speeds (rpm), and at a constant temperature (35 °C). A lumped-parameter model was subsequently developed to replicate the pump's real behavior using Siemens’ Amesim software.</div><div>The pump was modeled with four isolated pumping volumes, assuming complete occlusion of the tube by the rollers. The deformability of the neoprene tube was incorporated using a generalized tubing law, treating it as a linearly elastic material.</div><div>Experimental results showed that due to neoprene's high deformability, the pump's flow rate depended significantly on Pin. Variations in suction pressure altered the tube's expansion and contraction, affecting the volume of liquid between rollers. Conversely, the flow rate showed minimal dependence on Pout. These trends were also validated through the lumped-parameter model, with simulated data aligning within the experimental volumetric efficiency's mean ± one standard deviation for all tested conditions.</div><div>This study provides a simplified but accurate and validated model for peristaltic pumps, which provides the total flow processed by the pump, the flow and pressure ripples and the pressure trend within the pumping volume.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101132"},"PeriodicalIF":0.0,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465199","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":"Thermal simulation for enhanced control in innovative ironing processes on 3D-printed components","authors":"Andrea Montalti,&nbsp;Alessandro Ghini,&nbsp;Gian Maria Santi,&nbsp;Alfredo Liverani","doi":"10.1016/j.ijft.2025.101137","DOIUrl":"10.1016/j.ijft.2025.101137","url":null,"abstract":"<div><div>This study investigates an innovative surface finishing process for 3D-printed components using Material Extrusion (MEX). By applying controlled heating to the outer layer with a heated, semi-spherical tip, surface quality can be enhanced without adding material, effectively reducing imperfections caused by nozzle deposition. Using a prototype tool with distinct thermal properties, simulations were conducted to assess the optimal process parameters, including tool temperature, movement speed, and depth of influence within the material. Thermal simulations of the tool were performed to analyse temperature distribution and efficiency, identifying potential heat losses. Additionally, interactions between the tool tip and the material were simulated, highlighting temperature distribution at various depths. The simulations reliably model the tool's performance, providing a solid foundation for precise process parameter calibration while minimising reliance on experimental testing. Analyses conducted on PLA, PETG, ABS, PEEK, and PEKK demonstrated a clear correlation between speed and temperature in achieving optimal results. For materials with a high glass transition temperature, either a lower speed or a higher tool temperature is required, depending on the material's thermal properties.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101137"},"PeriodicalIF":0.0,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143428259","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":"Fractional analysis for heat consumption of CuO-based hybrid nanofluid via integral transform","authors":"Firas Ghanim ,&nbsp;Ali Hasan Ali ,&nbsp;Ghassan Ezzulddin Arif ,&nbsp;Ali Raza","doi":"10.1016/j.ijft.2025.101135","DOIUrl":"10.1016/j.ijft.2025.101135","url":null,"abstract":"<div><div>The article covers two other sources of solar energy: industrial devices and nanofluids, which are employed in thermal engineering. The article makes the case that thermal engineering and industrial solar energy technologies can generate solar energy from alternative sources, such as nanofluids. Fractal fractional derivatives are a new and modified type of fractional derivative that has been developed to solve issues with hybrid nanofluid suspension. Several numerical techniques, such as Stehfest's and Tzou's algorithms, and the integral transform method, also known as Laplace transformation, are used to examine the approximate solution of the governed PDEs. At various time values, the numerical impacts of heat and flow rate are discernible. We then deduced that the momentum and heat profiles decreased with increasing fractal limitations. Furthermore, the momentum and temperature gradients progressively rise close to the plate and fall away from it when all prerequisites are satisfied. Because of the physical relevance of the nanoparticles under consideration, the water-based (<em>H</em>₂O) solution also has a more obvious influence when comparing various nanofluids than the (<em>CMC</em>)-based hybrid nanofluid.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101135"},"PeriodicalIF":0.0,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143428266","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":"Thermal and combustion performance of a swirl-stabilized meso-combustor for micro-power generation","authors":"Soroush Sheykhbaglou,&nbsp;Amirreza Ghahremani,&nbsp;Sadegh Tabejamaat","doi":"10.1016/j.ijft.2025.101133","DOIUrl":"10.1016/j.ijft.2025.101133","url":null,"abstract":"<div><div>Combustion-driven thermoelectric and thermophotovoltaic power systems taking advantage of meso‑ and micro-scale combustors, that are direct energy conversion modules, have attracted growing interest. So, in this research, three double annulus axial swirlers are implemented to investigate the effect of swirl direction of the fuel and air flows with respect to each other on thermal performance and combustion characteristics of a non-premixed meso‑scale combustor. This study comprehensively evaluates several key performance metrics of the meso‑combustor, including its operational envelope, flame characteristics, exhaust gas temperature, mean outer wall temperature and its uniformity, pollutant emissions, wall heat losses, and thermal efficiency. It is found that adding swirl to the co-axial airflow significantly enhances the operational envelope, expanding it by &gt;600 % in comparison to zero-swirl airflow configuration. Co-rotating swirling flows is reported to have a more positive influence on flame blow-out than counter-rotating swirling flows. Furthermore, the flame lift-off height decreases with an increase in airflow rate for a set fuel flow rate, with the lift-off heights in the co-swirl configuration demonstrating the least sensitivity to increases in fuel flow rate. Analysis of the combustion products reveals that CO concentration has a U-shaped dependency of the equivalence ratio, where the co-swirl mode exhibits lower CO concentrations by approximately 31 % compared to the counter-swirl mode. Additionally, the co-swirl mode displays the superior values of exhaust gas temperature (∼ 3.3 %), combustion efficiency (∼ 34 %), mean outer wall temperature (4.6 %), radiation efficiency (∼ 15 %), and thermal efficiency (∼ 3.5 %) compared with counter-swirl mode under identical operating conditions.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101133"},"PeriodicalIF":0.0,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446046","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":"Performance enhancement of double-rotor viscous micropump for transporting Bingham fluid","authors":"Melika Mohammadi,&nbsp;Ali Ahmadpour,&nbsp;Seyed Amin Chabok","doi":"10.1016/j.ijft.2025.101134","DOIUrl":"10.1016/j.ijft.2025.101134","url":null,"abstract":"<div><div>Rotary viscous micropumps, recognized as a prevalent mechanism in microfluidics systems, have recently been introduced to transport non-Newtonian fluids, especially yield-stress fluids. However, conventional single-rotor viscous micropumps often lack efficiency and effectiveness when dealing with these particular fluid types. To address this challenge, the present study explores the use of dual-rotor viscous micropumps for transporting Bingham fluids and their associated performance enhancement for the first time. In a four-step approach, the effects of geometrical and operational parameters, including diameter ratio, distance ratio, rotational velocity ratio, and height ratio on two performance metrics, flow rate, and efficiency, are analyzed, and optimal values are recorded. Enhanced designs, optimized for maximum flow rate and efficiency, are evaluated at four distinct Bingham numbers (Bn), with comparative performance assessments against single-rotor micropumps. The working fluid is simulated using the Herschel-Bulkley model to capture its non-Newtonian behavior, with velocity and viscosity contours providing insights into flow characteristics. Numerical findings reveal significant performance improvements with dual-rotor micropumps, achieving a maximum enhancement rate of 12 while Bn = 2 compared to single-rotor configurations. Additionally, the adverse effects of yield stress on both efficiency and flow rate are substantially mitigated, particularly for high-viscosity fluids, due to a reduction in blocking vortex structures. These findings highlight the potential of dual-rotor viscous micropumps as an effective solution for transporting yield-stress fluids.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101134"},"PeriodicalIF":0.0,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419892","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 review on machine learning applications in hydrogen energy systems","authors":"Zaid Allal ,&nbsp;Hassan N. Noura ,&nbsp;Ola Salman ,&nbsp;Flavien Vernier ,&nbsp;Khaled Chahine","doi":"10.1016/j.ijft.2025.101119","DOIUrl":"10.1016/j.ijft.2025.101119","url":null,"abstract":"<div><div>Adopting machine learning (ML) in hydrogen systems is a promising approach that enhances the efficiency, reliability, and sustainability of hydrogen power systems and revolutionizes the hydrogen energy sector to optimize energy usage/management and promote sustainability. This study explores hydrogen energy systems, including production, storage, and applications, while establishing a connection between machine learning solutions and the challenges these systems face. The paper provides an in-depth review of the literature, examining not only ML techniques but also optimization algorithms, evaluation methods, explainability techniques, and emerging technologies. By addressing these aspects, we highlight the key factors of new technologies and their potential benefits across the three stages of the hydrogen value chain. We also present the advantages and limitations of applying ML models in this field, offering recommendations for their optimal use. This comprehensive and precise work serves as the most current and complete examination of ML applications within the hydrogen value chain, providing a solid foundation for future research across all stages of the hydrogen industry.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101119"},"PeriodicalIF":0.0,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394835","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":"Process development and simulation of a novel solar energy plant integrated with solid oxide fuel cell, hydrogen, heat recovery and carbon capture systems","authors":"Muhammad Ishaq,&nbsp;Ibrahim Dincer","doi":"10.1016/j.ijft.2025.101122","DOIUrl":"10.1016/j.ijft.2025.101122","url":null,"abstract":"<div><div>Solid oxide fuel cell (SOFC) releases significant high-temperature thermal energy during its operational mode. If this heat is not managed properly, it leads to thermal stresses, material shocks, and degradation. To effectively utilize such a high-temperature heat, this work presents a thermodynamic analysis and environmental assessment of a novel concept that synergistically integrates a benchmark SOFC with a four-step hybrid Cu-Cl thermochemical cycle. The developed system incorporates a SOFC unit for electricity generation, an afterburner for the complete oxidation of unreacted fuel (H₂, CO), a thermochemical cycle for utilizing high-temperature heat, a supporting Rankine Cycle (SRC), and an H₂ and CO₂ compression unit. The system is simulated by solving mass, energy, and exergy balances at steady-state conditions. Pinch point analysis is conducted using MATLAB to assess the thermodynamic feasibility of H₂ production. Furthermore, the specific primary energy consumption per unit of CO₂ avoided (SPECCA) is calculated to assess the system's environmental impacts. It is found that the CO₂ and H₂ compression train exhibit an overall exergy destruction of 5.83 kJ/mol of CO₂ and 5.98 kJ/mol of H₂ respectively. The thermolysis reactor of the Cu-Cl cycle carries the highest exergetic losses, with a share of 34.39%. The system exhibits a SPECCA value of 8.27 with 0.114 MJ/kg CO₂, considering the options with and without the Cu-Cl thermochemical cycle. The system's overall energy and exergy efficiencies are also 64.45% and 59.07% respectively.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101122"},"PeriodicalIF":0.0,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419891","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 Cattaneo-Christov heat and surface temperature on viscoelastic non-newtonian micropolar nanofluids: Darcy exponential sheet flow with planktonic microorganisms","authors":"Muhammad Waseem ,&nbsp;Ihab Omar ,&nbsp;Muhammad Jawad ,&nbsp;Taoufik Saidani ,&nbsp;Qasem M. Al-Mdallal","doi":"10.1016/j.ijft.2025.101131","DOIUrl":"10.1016/j.ijft.2025.101131","url":null,"abstract":"<div><div>This paper investigates the influence of chemical reactions and variable magnetic field on three dimensional Oldroyd B micropolar nanofluids subjected to exponentially stretching sheet in the presence of motile microbes. The study incorporates several significant physical phenomena, including Cattaneo-Christov heat<span><math><mo>,</mo></math></span> thermal radiation<span><math><mo>,</mo></math></span> chemical reaction kinetics<span><math><mo>,</mo></math></span> and Darcy-Forchheimer effects. A particularly novel aspect of PST (prescribed surface temperature) and PHF (prescribed heat flux) are taken into account. The governing nonlinear PDEs of Oldroyd B fluids with thermophoretic diffusion and Brownian motion are transformed in to nonlinear ODEs via similarity functions. The resulting set of nonlinear ODEs are solved numerically via MATLAB platform and compared the results with published literature through bvp4c built-in code for better agreement. The results of on different parameters like Peclet number, Forchheimer number, thermal relaxation time, chemical reaction, Prandtl number, Schmidt number, porosity parameter, heat source coefficient and magnetic parameter on Skin friction, Nusselt number, Sherwood number and motile density number are discussed in detail through graphs, tables and literature. It is declared that Skin friction coefficients decline for developed values of magnetic parameter<span><math><mrow><mspace></mspace><mi>M</mi></mrow></math></span>, porosity parameter<span><math><mrow><mspace></mspace><msub><mi>K</mi><mn>1</mn></msub></mrow></math></span>.and viscoelastic parameter<span><math><mrow><mspace></mspace><msub><mi>K</mi><mn>2</mn></msub></mrow></math></span>. The thermal boundary layer thickness decreases with growing value of Prandtl number. The findings have significant implications for industrial and engineering processes where heat transfer is major issue.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101131"},"PeriodicalIF":0.0,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143428265","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":"Ocean thermal energy conversion net power maximization for the optimization of plate heat exchanger geometry","authors":"Kevin Fontaine ,&nbsp;Takeshi Yasunaga ,&nbsp;Yasuyuki Ikegami","doi":"10.1016/j.ijft.2025.101115","DOIUrl":"10.1016/j.ijft.2025.101115","url":null,"abstract":"<div><div>Ocean Thermal Energy Conversion is a steady source of renewable energy that uses the natural temperature gradient within the ocean but requires large and expensive heat exchangers, considerably contributing to the overall cost. Thus, this study focuses on finding optimum herringbone plate heat exchangers geometry leading to the highest net power output to heat transfer area ratio <span><math><mrow><mo>(</mo><msub><mrow><mi>w</mi></mrow><mrow><mi>n</mi><mi>e</mi><mi>t</mi></mrow></msub><mo>)</mo></mrow></math></span>. A method to assess and maximize <span><math><msub><mrow><mi>w</mi></mrow><mrow><mi>n</mi><mi>e</mi><mi>t</mi></mrow></msub></math></span> is developed, applied to a heat exchanger geometry from the literature, before being used to find optimum geometries , which resulted in a 33.8% increase in <span><math><msub><mrow><mi>w</mi></mrow><mrow><mi>n</mi><mi>e</mi><mi>t</mi></mrow></msub></math></span> compared with the geometry used as reference, at chevron angles of 48.7° and 30°, mean channel spacing of 3.7 and 1.5 mm, corrugation pitches of 15 and 6.0 mm, and width to length ratios of 0.6 and 1 for the evaporator and condenser, respectively. The effect of each parameter is also analyzed showing a high impact of evaporator mean channel spacing and corrugation pitch and identified possible geometries for further studies. A sensitivity analysis revealed a design gross power with, granted a sufficient pipe diameter, negligible effect on optimum geometries, while the heat source temperature difference yielded two possible optimum for the condenser and a potential single one for the evaporator.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101115"},"PeriodicalIF":0.0,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419890","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":"Thermal radiation and thermo-diffusion in Casson-ferrofluid over a magnetized porous surface: RSM analysis","authors":"S. Manjunatha ,&nbsp;J. Santhosh Kumar ,&nbsp;Khalil Ur Rehman ,&nbsp;Wasfi Shatanawi ,&nbsp;S.V.K. Varma","doi":"10.1016/j.ijft.2025.101130","DOIUrl":"10.1016/j.ijft.2025.101130","url":null,"abstract":"<div><div>A wide variety of heat transfer applications employ ferrofluids. These include heat exchangers, materials research, and a host of other industries, such as food processing, solar trough collectors, and aerospace engineering. The main goal of this study is to investigate how fluid moves through a porous medium stretched across a Casson ferrofluid bilinear stretching surface, accounting for the effects of slip and magnetic fields. This study takes into account factors such as thermal radiation, heat source/sink, first-order chemical reactions, Soret, and Dufour effects. Similarity transformations convert the flow model's governing nonlinear coupled partial differential equations into ordinary coupled differential equations. The results are obtained using the time-saving bvp4c approach in MATLAB along with the shooting technique and presented in graphs and tables. The derived quantities, namely skin friction, Nusselt number, and Sherwood number at the stretching surface, are also computed. The effects of various parameters on flow-derived quantities have been analyzed and discussed. The momentum boundary layer drops as the Casson parameter rises. As the magnetic parameter raises, the fluid velocity drops, while the fluid temperature exhibits the opposite phenomenon. As radiation and heat sources increase, the temperature rises, whereas the Dufour effect leads to the opposite outcome. The adjusted R-squared and R-squared for skin friction achieve a value of 99.92 %. Compared to the Dufour effect, the Nusselt number is more affected by the heat source and thermal radiation parameter. Some important contributions include discussing response surface methods and studying the complex connections between Casson fluid, porosity, and the stretching ratio parameter.</div></div>","PeriodicalId":36341,"journal":{"name":"International Journal of Thermofluids","volume":"26 ","pages":"Article 101130"},"PeriodicalIF":0.0,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143379164","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}