International Journal of Thermal Sciences最新文献

{"title":"Experimental and numerical analysis of a novel constructal design for canopy-to-canopy liquid cooling systems","authors":"José Félix Guil-Pedrosa ,&nbsp;Luis Miguel García-Gutiérrez ,&nbsp;Antonio Soria-Verdugo ,&nbsp;Sylvie Lorente","doi":"10.1016/j.ijthermalsci.2025.109918","DOIUrl":"10.1016/j.ijthermalsci.2025.109918","url":null,"abstract":"<div><div>The cooling capacity of canopy-to-canopy flat plates with the coolant inlet and outlet on the same side of the plate was analyzed in detail, both experimentally and numerically. A novel constructal design was proposed to derive the diameter of each branch of canopy-to-canopy configurations. Thanks to the predicted diameter ratios, the new design results in a reduction of the coolant pumping power of 60 % to achieve the same maximum temperature as a traditional configuration with equal diameters in all branches. Four canopy-to-canopy configurations with a number of branches ranging from 2 to 5 were designed based on this innovative constructal approach to optimize the cooling capacity of flat plate systems, keeping the same fluid volume for all of them. The resulting designs were tested experimentally and modelled for steady state and transient cooling operations. A higher number of branches improved the steady state cooling performance under continuous heating, as the 5-branches configuration yielded the lowest maximum and mean temperatures while maintaining similar temperature homogeneity in both experimental measurements and numerical simulations. The maximum deviation between experimental and numerical results was 1.4 °C for both maximum and average temperatures, allowing the validation of the numerical models. For the transient cooling process, the flat plates experienced a progressively faster temperature reduction over time as the number of branches in the design increases, accelerating the cooling process by 14.7 % when increasing the number of branches from 2 to 5. The results show that the 5-branches canopy-to-canopy configuration has an excellent cooling capacity with a limited pressure drop to circulate the coolant.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109918"},"PeriodicalIF":4.9,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Entropy optimization and Prandtl-Eyring non-Newtonian fluid flow with second-order slip conditions past a curved Riga sheet; numerical simulation","authors":"Bilal Ali ,&nbsp;Yue-Ting Zhou ,&nbsp;Sidra Jubair ,&nbsp;Muzammal Hameed Tariq ,&nbsp;Abhinav Kumar ,&nbsp;Md Irfanul Haque Siddiqui","doi":"10.1016/j.ijthermalsci.2025.109916","DOIUrl":"10.1016/j.ijthermalsci.2025.109916","url":null,"abstract":"<div><div>The non-Newtonian (NN) Prandtl-Eyring fluid (PEF) model can be used to optimize conditions for processing, ensure substance high quality and consistency, and anticipate melted polymer flow behavior. This paper looks into an intriguing feature of irreversibility estimation through NN-PEF flow over a curved Riga surface. The impact of second-order slip conditions, thermal radiation, and exponential heat source/sink are also elaborated. The flow equations of NN-PEF have been reformulated into a dimensionless representation of differential equations (DEs) with an application of similarity conversions. The obtained lowest-order differential equations are numerically solved through the PCM (parametric continuation method). For accuracy of the results, the outcomes are compared to both experimental and theoretical results. The relative percent error between the present findings and the published numerical results at Re = 5000 is 0.71094 %. The rate of heat transfer (W/m²K) enhances from 4238.0724 to 44390.4205 at Re = 1594 to 440. The relative error between published experimental and present results is about 0.0029 % at Re = 440, which ensures the reliability of the proposed model and applied methodology. The velocity field of PEF is significantly boosted with the positive variation in 1st and 2nd order slip parameters. The influence of the Brinkmann number and heat radiation factor is enhanced, while the consequences of the temperature ratio parameter drop the rate of entropy generation in the system.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109916"},"PeriodicalIF":4.9,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143769216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of fan speed, sample orientation, and tray structure on heat transfer and food freezing time in batch air blast freezer","authors":"Zheng Xu ,&nbsp;Mark Anthony Redo ,&nbsp;Yvan Llave ,&nbsp;Yasushi Koga ,&nbsp;Manabu Watanabe","doi":"10.1016/j.ijthermalsci.2025.109915","DOIUrl":"10.1016/j.ijthermalsci.2025.109915","url":null,"abstract":"<div><div>The batch air blast freezer is commonly used in the food industry, but nonuniform airflow distribution has been an on-going challenge. In this study, experiments and numerical simulations were performed to investigate the effects of varying the fan speed, sample orientation, and tray structure on flow dynamics, local heat transfer coefficient, and transient temperature of loaded samples. Ice crystallization and freezing times of individual samples were predicted, and strong and weak convection locations were identified. Increasing the fan speed from 560 rpm to 840 rpm resulted in a 34%–39% increase in the average surface heat transfer coefficient of the samples in weak convection locations, leading to a reduction in ice crystallization and total freezing times by 20%–29%. The change in sample orientation exhibited a slight difference in freezing time, but the transition from trays to wire shelves demonstrated a substantial enhancement in convective heat transfer by 19%–22%, reducing the total freezing time by 10%–13%.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109915"},"PeriodicalIF":4.9,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143769215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transition and heat transfer in a water filled cubic cavity with convectively heated sidewalls","authors":"Md Harun Rashid ,&nbsp;Feng Xu","doi":"10.1016/j.ijthermalsci.2025.109913","DOIUrl":"10.1016/j.ijthermalsci.2025.109913","url":null,"abstract":"<div><div>Transition and heat transfer in a water filled cubic cavity with convectively heated sidewalls are investigated using three dimensional numerical simulations due to the practical significance in environment and industry. The numerical study is performed for a range of Rayleigh number (<em>Ra</em>) from 10⁰ to 5 × 10⁸ for which the working fluid is water (Pr = 7.74). Such a range of Rayleigh numbers shows a complex transition route to chaos of natural convection involving successive bifurcations. The first pitchfork bifurcation occurs under steady convection regime between <em>Ra</em> = 3.3 × 10⁴ and <em>Ra</em> = 3.4 × 10⁴ based on the topologic invariant relation. Further, more pitchfork bifurcations happen as <em>Ra</em> is increased. Additionally, a Hopf bifurcation occurs between <em>Ra</em> = 2.6 × 10⁹ and <em>Ra</em> = 2.7 × 10⁹ at which natural convection becomes periodic. Further bifurcations may also occur between <em>Ra</em> = 3.2 × 10⁹ and <em>Ra</em> = 3.3 × 10⁹ from periodic to period doubling state and between <em>Ra</em> = 3.3 × 10⁹ and <em>Ra</em> = 3.4 × 10⁹ from period doubling to quasi-periodic state. For a large Rayleigh number of <em>Ra</em>≥3.9 × 10⁹, natural convection becomes chaotic. To characterize the transition to chaos, topologic invariant relation, spectrum, attractor, maximum Lyapunov exponent, and fractal dimension are adopted. In addition, heat transfer is analyzed and scaled under different regimes.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109913"},"PeriodicalIF":4.9,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nanoparticle-enhanced bubble nucleation and heat transfer in nanoscale pool boiling","authors":"Yiqian Peng,&nbsp;Yuling Zhai,&nbsp;Bojie Zhou,&nbsp;Zhouhang Li,&nbsp;Hua Wang","doi":"10.1016/j.ijthermalsci.2025.109917","DOIUrl":"10.1016/j.ijthermalsci.2025.109917","url":null,"abstract":"<div><div>Boiling heat transfer is well-known for its efficient multiphase properties and has been extensively studied. However, integrating nanofluids into boiling processes remains relatively underexplored, requiring a detailed understanding of their heat transfer characteristics. This work investigates the bubble behavior and heat transfer characteristics of deposited copper (Cu) nanoparticles on a platinum (Pt) heating substrate during pool boiling using molecular dynamics. Results show that bubbles initially nucleate on the Cu nanoparticle surface, coalesce from both sides and eventually form a vapor film. This film detaches from both the nanoparticle and the substrate. In a pure argon (Ar) system, bubbles nucleate directly on the substrate and detach immediately after coalescence. This leads to a 15.07 % increase in heat flux, a 13.7 % reduction in nucleate boiling onset time, and a 17.9 % increase in maximum evaporation. Among spherical, cylindrical, square, and conical deposited Cu nanoparticles, bubbles nucleate earliest at the edges of square nanoparticles, with nucleation occurring 8.7 % earlier and achieving 17.35 % higher maximum heat flux before nucleate boiling than in spherical nanoparticles. Additionally, nanoparticles with greater surface roughness and smaller specific surfaces favor bubble formation and growth. Ar vapor infiltrates the bubbles, enhancing buoyancy and promoting their detachment from the conductive layer. Moreover, weakened surface tension and lower surface energy facilitate bubble detachment. Resulting pores provide nucleation sites, enhancing vapor-liquid interaction and improving heat transfer efficiency.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109917"},"PeriodicalIF":4.9,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of using circular and porous circular fins on the thermal performance of a shell and helically coiled heat exchanger: A numerical and experimental study","authors":"Ataollah Khanlari ,&nbsp;Adnan Sözen ,&nbsp;Halil İbrahim Variyenli ,&nbsp;Azim Doğuş Tuncer ,&nbsp;Kambiz Vafai","doi":"10.1016/j.ijthermalsci.2025.109894","DOIUrl":"10.1016/j.ijthermalsci.2025.109894","url":null,"abstract":"<div><div>A novel form of shell and helically coiled heat exchangers, which are widely employed in many applications, have been experimentally and numerically investigated in this work. In the current work, it is aimed to use a cost-effective and simple approach for improving heat transfer in a shell and helically coiled heat exchanger. Accordingly, a shell and helically coiled tube heat exchanger has been modified with a guiding tube and circular fins with the aim of guiding cold flow over the helically coil for enhancing heat transfer rate. In the first step of the study, numerical analyses have been conducted in order to reveal the impact of new modification on the heat transfer. In the next step, a modified heat exchanger with guiding tubes and circular fins has been manufactured and experimentally examined with water and ZnFe₂O₄/water magnetic nanofluid at different working conditions. The overall results of this study demonstrated how well the modified heat exchanger with circular fins and a guiding tube was designed. Adding a guiding tube into the shell part of the heat exchanger led to moderate the fluid flow and circular fins distributed the flow over the coil which upgraded heat transfer. Experimentally obtained results showed that using ZnFe₂O₄/water nanofluid in the SHCHE averagely upgraded the heat transfer coefficient as 12.4 %. Moreover, the average deviation between numerically and experimentally obtained outlet temperature is 4.1 %.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109894"},"PeriodicalIF":4.9,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated liquid-cooled battery module with dual functions: Thermal runaway suppression and early warning via flexible pressure sensors","authors":"Ruixin Ma ,&nbsp;Weixiong Wu ,&nbsp;Zekun Jiang ,&nbsp;Qiang Li ,&nbsp;Xiaoyuan Xu ,&nbsp;Ping Zhuo ,&nbsp;Hong Kang ,&nbsp;Dandong Wang ,&nbsp;Binbin Yu ,&nbsp;Junye Shi ,&nbsp;Jiangping Chen","doi":"10.1016/j.ijthermalsci.2025.109908","DOIUrl":"10.1016/j.ijthermalsci.2025.109908","url":null,"abstract":"<div><div>The demand for enhanced thermal safety performance in energy storage battery systems is increasingly rigorous. In practical applications, the management system with multi-function integration features, especially the combination of passive thermal management and active early warning, shows great potential. In this study, a novel large-capacity battery module is designed and assembled, integrating flexible pressure sensors for active warning function without compromising system structure. For thermal management, a cold plate/aerogel pad coupled structure is established and tested with a circulation refrigeration system under an overheating thermal runaway (TR) experiment system. First, the performance of cold plates and/or aerogel pads is compared, with cold plate flow rates of 0.3 L/min and 1 L/min, and an aerogel pad thickness of 1.5 mm. The results demonstrate that both cold plates and aerogel pads independently demonstrate the ability to prevent TR propagation. A comparative analysis of heat transfer power from the TR battery to the adjacent battery reveals that the aerogel pad is critical for significantly reducing heat transfer, irrespective of the presence of a cold plate. The aerogel pad reduces the peak heat transfer power by 59 % compared to the blank module. Additionally, the integration of only 0.46 mm-thick thin-film pressure sensors enables pressure distribution detection across the battery surface during TR process. The maximum pressure (P_max), representing the highest pressure point across the entire battery surface, is identified as an excellent early warning signal. In a typical energy storage battery module using cold plate and aerogel pads, the P_max early warning for TR precedes temperature, voltage, and expansion force signals by 1212 s, 1158 s, and 72 s, respectively. The P_max peak reaches 1114 kPa and lasts for 138 s, enhancing the reliability in preventing false alarms.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109908"},"PeriodicalIF":4.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of microchannel heat transfer characteristics based on topology optimization","authors":"Yuwei Liu ,&nbsp;Changhui Chen ,&nbsp;Yanpeng Yuan ,&nbsp;Jiasong Yang ,&nbsp;Zhiqiang Guo ,&nbsp;Jiawei Shi","doi":"10.1016/j.ijthermalsci.2025.109898","DOIUrl":"10.1016/j.ijthermalsci.2025.109898","url":null,"abstract":"<div><div>Based on the dual-objective topology optimization method, four microchannel configurations with differing inlet and outlet arrangements are studied in this paper. The influences of the aspect ratio, weight coefficient and Reynolds number on the optimized design variable, temperature and pressure fields have been investigated. Comparative analysis of heat transfer characteristics in microchannels with different structures is implemented using the entransy dissipation theory and the field synergy principle. The results show that the maximum temperature demonstrates higher sensitivity to aspect ratio and weighting factor variations in DMC and 3SMC configurations compared to Reynolds number effects. Pressure drop characteristics exhibit that the weighting factor has the most significant impact on 2SMC, while aspect ratio determines 3SMC behavior. In addition, DMC achieves the highest entransy dissipation and the best heat transfer efficiency, while CMC presents the best synergy between velocity and temperature fields, superior flow characteristics and optimal thermal performance.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109898"},"PeriodicalIF":4.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study on supercritical carbon dioxide convective heat transfer in fractured rocks","authors":"Sapargeldi Amangeldiyev ,&nbsp;Yan Wang ,&nbsp;YongZhi Yang ,&nbsp;Xin-Rong Zhang","doi":"10.1016/j.ijthermalsci.2025.109874","DOIUrl":"10.1016/j.ijthermalsci.2025.109874","url":null,"abstract":"<div><div>This study developed an innovative flow-heat transfer experimental system that can cover the operating range of subcritical to supercritical pressures (up to 60 MPa) and accurately simulate real geological conditions. Utilizing supercritical CO₂'s superior thermophysical properties, we conducted a series of well - designed convective heat transfer experiments within a smooth/artificial fracture of Sichuan outcrop rocks. The key parameters influencing the heat transfer, such as rock properties, morphology of fracture, injection flow, and the initial temperature of rock sample, were measured and analyzed. A new correlation formula was developed, showing a 25 % deviation from classical models but achieving a 4.37 % mean absolute error against experimental data. Test results show that the high temperature heat energy of nearly 60–70 °C can be recovered from the sandstone reservoir, which is higher 10 °C than that of the carbonate rock. The initial temperature of the sample directly affects the fluid physical property, and lead to change of heat transfer performance and production. Under the same initial temperature, the higher flow rate, the faster the production temperature drops. Due to the neglect of thermodynamic expansion effect in traditional fluid mechanics analysis, the influence of thermodynamic expansion on flow acceleration is deduced from the measurement of experimental temperature and pressure gradient, and a modified continuous equation including acceleration term is proposed to describe the flow process more accurately. It provides theoretical basis and technical support for optimizing geothermal energy storage system, and helps to improve energy utilization efficiency and reduce carbon emissions.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109874"},"PeriodicalIF":4.9,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Film heating heat transfer and effectiveness measurements for mainstream flow over a conical surface","authors":"Anilkumar Vajubhai Gorasiya,&nbsp;R.P. Vedula","doi":"10.1016/j.ijthermalsci.2025.109902","DOIUrl":"10.1016/j.ijthermalsci.2025.109902","url":null,"abstract":"<div><div>Adiabatic effectiveness and heat transfer coefficient measurements for fluid injection into the mainstream over a conical surface have been presented in this article. The axis-symmetric nature of the flow over the cone makes the heat transfer behaviour different from that observed for a flat surface, and dependent on the cone apex angles which were kept constant at 30° and 70° in the study. The injection angle was kept equal to 30° and 50° with respect to the surface of the cone and the blowing rate was varied between 0.3 and 2.5. The spatially resolved surface temperature measurements over the cone using an IR thermal camera were used to obtain the adiabatic effectiveness and heat transfer coefficient ratio values. The maximum values of the effectiveness for the 30° and 70° cones with 30° injection angle at locations along the centreline and in between the holes were 0.34, 0.22 and 0.24, 0.22 respectively at X/d = 5.5 for the lowest blowing ratio M = 0.3. The maximum increase in the heat transfer coefficient ratio was nearly equal to 30 % for both cones at 30° injection angle at the hole centreline at X/d =5.5 at the highest blowing rate M = 2.5. The effectiveness and heat transfer coefficient ratio experienced a reduced cross stream variation, compared to the flat surface case, for all cases studied.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109902"},"PeriodicalIF":4.9,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}