International Journal of Thermal Sciences最新文献

{"title":"Numerical thermohydraulic investigation of developing mixed convective laminar flow through horizontal tubes with a uniform wall temperature","authors":"Deniél Steyn ,&nbsp;Marilize Everts ,&nbsp;Ken J. Craig","doi":"10.1016/j.ijthermalsci.2025.109955","DOIUrl":"10.1016/j.ijthermalsci.2025.109955","url":null,"abstract":"<div><div>A numerical investigation of simultaneously developing laminar mixed convective flow in a horizontal tube under a uniform wall temperature (UWT) boundary condition was conducted. Two numerical models were created to examine the differences between experimental and numerical approaches. The first replicated an experimental UWT setup, while the second implemented an ideal UWT boundary condition. Simulations were performed in ANSYS Fluent with temperature-dependent water properties. The Reynolds number and Grashof number ranges were 500-2000 and 0.18×10³-9.43×10³, respectively. Length-to-diameter ratios varied between 1020 and 1632. The circulation strength of buoyancy-driven vortices was calculated to quantify free convection effects. Higher Grashof numbers intensified the circulation strength and shifted the peak circulation strength upstream. Increased Reynolds numbers delayed the occurrence of peak circulation strength without altering its magnitude. A boundary layer analysis indicated longer thermal and hydrodynamic entrance lengths with higher Grashof numbers or Reynolds numbers. Furthermore, the local Nusselt number decreased from a maximum at the tube inlet to a trough and then increased to a peak before declining to a value of 3.66. Elevated Grashof numbers amplified these trends and shifted the troughs and peaks upstream, whereas increasing Reynolds numbers delayed these extrema points without significantly affecting their magnitudes. Based on circulation strength and boundary layer behaviour, seven thermohydraulic regions were defined: (1) hydrodynamic-merge, (2) free convection increasing, (3) free convection dominating, (4) free convection settling, (5) sustained free convection, (6) hydrodynamically fully developed forced convective flow, and (7) thermally fully developed forced convective flow.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"215 ","pages":"Article 109955"},"PeriodicalIF":4.9,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143860314","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":"Endwall aerothermal and vane phantom cooling performances of turbine nozzle guide vane with trenched holes from applying TBCs","authors":"Bo Bai ,&nbsp;Hao Zhang ,&nbsp;Zhigang Li ,&nbsp;Jun Li ,&nbsp;Shuo Mao ,&nbsp;Wing F. Ng","doi":"10.1016/j.ijthermalsci.2025.109942","DOIUrl":"10.1016/j.ijthermalsci.2025.109942","url":null,"abstract":"<div><div>To mitigate the adverse impacts triggered by partial blockage of film holes, the transverse trenches were introduced during thermal barriers coatings (TBCs) application, and various trenched hole schemes of double-row discrete film hole layouts were designed in this paper, particularly upstream trenched holes (UTH), fully trenched holes (FTH) and downstream trenched holes (DTH-1, DTH-2 and DTH-3). In addition, the fully common hole (FCH) and fully blocked hole (FBH) configurations were also provided for comparative analysis of endwall aerothermal performance in realistic turbine cascades. Based on the double-coolant temperature model, endwall aerothermal, vane pressure side (PS) phantom cooling and cascade aerodynamic performances, were analyzed and discussed at design coolant delivery pressure. Results indicated that the transverse trenches contribute to recovering the coolant delivery capacity of film holes, increasing the mass flow ratio from 1.32 % to 1.88 %. Endwall film cooling performance decay triggered by partial film hole blockage can be mitigated by introducing transverse trenches at the downstream film holes (row 2), and even a significant enhancement (more than 40 % in magnitude) is obtained in the region upstream endwall (−0.2 <em>Cx</em> &lt; <em>x</em> &lt; 0). Even though the single-row narrow trenches have a negative impact on vane PS phantom cooling performance, leading to a slight decrease (less than 10 % in levels) compared to the FBH configuration, the root of vane PS is still protected by the separated upstream purge flow at DTH-1 and DTH-3 configurations. Due to enhanced vortex systems near endwall and coolant momentum dissipation, and induced additional vortex system, the thermodynamic energy loss coefficient increases by 0.09 %–0.57 % at trenched hole configurations. In addition, the position of the downstream trenched lip plays a key role in the endwall aerothermal, phantom cooling and cascade aerodynamic performances, and thus, trenched hole schemes should be carefully considered and designed. In general, based on the combined consideration of coolant flow depletion, metal substrate exposure risks and film cooling benefits, the downstream narrow transverse trenches are suggested to be introduced in this film hole layout during TBCs application.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"215 ","pages":"Article 109942"},"PeriodicalIF":4.9,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143860344","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":"Analysis of different phase change materials (PCMs) and wall material in a nano-circular space thermal energy storage (TES) system: A molecular dynamics approach","authors":"Cheng Cao ,&nbsp;Ali B.M. Ali ,&nbsp;Zahraa Abed Hussein ,&nbsp;Narinderjit Singh Sawaran Singh ,&nbsp;Barno Abdullaeva ,&nbsp;Ahmad Zubair ,&nbsp;Soheil Salahshour ,&nbsp;Sh Baghaei","doi":"10.1016/j.ijthermalsci.2025.109954","DOIUrl":"10.1016/j.ijthermalsci.2025.109954","url":null,"abstract":"<div><div>Thermal energy storage (TES) play a vital role in overcoming the fluctuating nature of solar thermal energy. To study and understand the performance of these systems, using new techniques such as computer simulations can be useful. In this article, a specific circular nanochannel containing a phase change material (PCM) is introduced and its thermal and mass performance are investigated. By using two types of PCM and three wall metals (platinum, copper, and aluminum) the effects of changing several geometric and thermodynamic parameters are evaluated. In general, two different plans are proposed and parameters such as thermal conductivity, heat flux, charging, and discharging time are defined and evaluated. The obtained results show that the use of paraffin reduces the phase change time from 1.36 ns to 1.21 ns. Geometrical investigations also show that increasing the diameter ratio leads to a decrease in heat flux. Increasing the velocity of argon atoms in the inner tube also leads to an increase in the mobility of atoms and as a result improves the heat transfer rate. Using copper, the thermal conductivity is 54.3 % and 13.5 % higher than platinum and aluminum. The maximum heat flux for the two proposed cases is about 1500 and 1285 W/m2, respectively. Increasing the velocity of argon atoms from 0.01 Å/fs to 0.05 Å/fs leads to a decrease in the phase change time from 1.12 ns to 1.15 ns. Regarding the type of PCM, paraffin performs better than the combination of water-hydrocarbon.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"215 ","pages":"Article 109954"},"PeriodicalIF":4.9,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143865191","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":"Research on the pore defects formation and mechanical properties of Ti6Al4V for selective laser melting","authors":"Longchao He ,&nbsp;Ruixiang Bai ,&nbsp;Zhenkun Lei ,&nbsp;Da Liu ,&nbsp;Ning Wang ,&nbsp;Yaoxing Xu ,&nbsp;Cheng Yan","doi":"10.1016/j.ijthermalsci.2025.109948","DOIUrl":"10.1016/j.ijthermalsci.2025.109948","url":null,"abstract":"<div><div>This study investigates the preparation of Ti6Al4V specimens under various process conditions using selective laser melting. A high accuracy thermal-fluid coupling model is developed to investigate the physical mechanisms underlying pore defect formation during processing. Micro-morphology is characterized using optical microscopy and scanning electron microscopy. The results indicate that the microstructure primarily consists of pin martensite α′ at high cooling rates (10⁶–10⁷ K/s). Pore defects resulting from incomplete melting of particles are observed within the sample under low heat input conditions. In contrast, a transient bubble is extruded from the base of the keyhole in the molten pool under higher heat input, leading to the formation of a keyhole pore defect (&gt;20 μm) upon captured by the solid-phase line. From the perspective of porosity-induced damage, the mechanical behavior of samples fabricated under various process conditions is further examined. The results demonstrate that defects reduce the component density. Furthermore, defects lead to stress concentration and a deterioration in mechanical properties. Porosity is a critical factor in part qualification. Porosity can be reduced, and mechanical properties improved, by adapting the process based on the pore defect formation mechanism.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"215 ","pages":"Article 109948"},"PeriodicalIF":4.9,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143855282","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":"Heat transfer enhancement in a tubular heat exchanger fitted with a novel baffle: A numerical study and experimental validation","authors":"Ramin Alipour ,&nbsp;Roozbeh Alipour ,&nbsp;Mohsen Rezaeimanesh ,&nbsp;Mohammad Hossein Tahan ,&nbsp;Mehdi Dehghan","doi":"10.1016/j.ijthermalsci.2025.109936","DOIUrl":"10.1016/j.ijthermalsci.2025.109936","url":null,"abstract":"<div><div>Inspired by the turbulence structure in Savonius turbines, an innovative baffle called SSB (Savonius-shaped baffle) was developed to enhance the convective heat transfer in a tubular heat exchanger (THX). The geometrical parameters of the baffles, including rotational angle(-45°≤α ≤ 45°), pitch ratio (0.625≤P_R ≤ 2.5), and aspect ratio (0.5≤A_R≤1), have been extensively evaluated through 280 Computational Fluid Dynamics (CFD) simulations to assess the Nusselt number (<em>Nu</em>), friction factor (f), and thermal enhancement factor (TEF) at various Reynolds numbers (5000≤Re ≤ 25000). Air, under steady-state flow conditions, was considered the working fluid, flowing through the smooth wall of the THX. The turbulence behavior of the flow was predicted using the K-ε-Realizable model. Both the fabricated experimental setup and empirical correlations validated the results. It was found that, due to the nature of turbulence generation, the SSB can enhance <em>Nu</em> by approximately 345 % at Re = 15000/P_R = 0.625/α = 0° compared to plain tubes. It also revealed that <em>Nu</em> and f increase as A_R and Re increase, while P_R decreases and TEF decreases as A_R and Re decrease. The maximum TEF achieved was 1.35 at A_R = 0.5/Re = 5000/P_R = 1.75/α = - 45°. Finally, assuming smooth conditions, an empirical correlation has been developed to predict <em>Nu</em>, taking into account Prandtl number (Pr), opening ratio (OR), Re, and PR, with absolute average relative deviations (AARD%) approximately equal to 9.64 % and 4.32 % for A_R = 1 and A_R = 0.5, respectively.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"215 ","pages":"Article 109936"},"PeriodicalIF":4.9,"publicationDate":"2025-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850734","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":"Applicable scope of the Rosseland model in predicting the radiative thermal conductivity of silica aerogel","authors":"Hai-Bo Xu ,&nbsp;Chuan-Yong Zhu ,&nbsp;Lin Tian ,&nbsp;Zeng-Yao Li","doi":"10.1016/j.ijthermalsci.2025.109953","DOIUrl":"10.1016/j.ijthermalsci.2025.109953","url":null,"abstract":"<div><div>Silica aerogel, renowned for its exceptional insulation properties, exhibits extremely low thermal conductivity at room temperature, with radiative heat transfer contributing significantly to its overall thermal performance at higher temperature. Its radiative thermal conductivity is predicted by the extensively-employed Rosseland diffusion approximation model developed under the optically thick hypothesis. It is imperative to ascertain its applicability, as failing to determine the appropriate conditions for the Rosseland model can result in significant prediction discrepancy under varying optical thickness. A coupled radiative and conductive heat transfer model is developed in this study, where radiative heat transfer is solved by a spectral band method applicable at any optical thickness. The effects of temperature, Rosseland optical thickness, and boundary surface emissivity on the radiative thermal conductivity are systematically analyzed while comparing with predictions from the Rosseland model. Finally, the applicable scope of the Rosseland diffusion approximation model in silica aerogel is obtained.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"215 ","pages":"Article 109953"},"PeriodicalIF":4.9,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143848287","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":"Enhancing latent heat storage dynamics with expanded graphite foam: Myth vs. reality check through numerical and experimental investigations","authors":"Narender Kumar ,&nbsp;Amit Shrivastava ,&nbsp;Sandip K. Saha ,&nbsp;Prodyut R. Chakraborty","doi":"10.1016/j.ijthermalsci.2025.109929","DOIUrl":"10.1016/j.ijthermalsci.2025.109929","url":null,"abstract":"<div><div>The solid–liquid phase transition, with its moderate latent heat absorption or release over a narrow temperature margin and minimal density difference, finds extensive use in various thermal engineering applications such as energy storage, electronics cooling, and personal cooling. Commonly used organic or inorganic phase change materials (PCM) suffer from low thermal conductivity, which can be addressed by composite PCMs (CPCM). CPCMs comprise highly porous compressed-expanded graphite (CEG) foam impregnated with PCM. While CPCM shows significantly improved thermal conductivity, porous CEG foam in CPCM suppresses free convection during the melting process, making the heat transfer mostly diffusion-dominated. Our study compares free convection-dominated melting of pure PCM with diffusion-dominated melting of CPCM, conducted through numerical and experimental analysis in a bottom-heated rectangular cavity. From this investigation, we find that CPCM offers significantly better temperature uniformity, leading to the eradication of potential hot spots, and is advantageous for heat sink applications. However, CEG volume fraction in CPCM above or below a specific range hampers the fast melting process in thermal storage applications in contrast to the conventional notion.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"215 ","pages":"Article 109929"},"PeriodicalIF":4.9,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850731","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 pressure on the oil shale convection heating in-situ conversion process","authors":"Tanen Jiang ,&nbsp;Lihong Yang ,&nbsp;Chaofan Zhu","doi":"10.1016/j.ijthermalsci.2025.109940","DOIUrl":"10.1016/j.ijthermalsci.2025.109940","url":null,"abstract":"<div><div>In-situ conversion technology represents the developmental trend for large-scale commercial exploitation of oil shale. High-pressure geological conditions significantly influence the pyrolysis kinetics of oil shale and the in-situ extraction process. This study conducted pyrolysis experiments on Qingshankou Formation oil shale from the Songliao Basin under varying nitrogen pressures, analyzing temperature fields, pressure fields, and oil production. Concurrently, CMG software was employed to simulate the in-situ extraction process through high-temperature nitrogen injection, evaluating the impact of pressure variations on extraction effectiveness from perspectives of reservoir properties, product yield, and energy utilization efficiency. Laboratory results indicated that increased pressure led to higher reaction temperatures and thermal losses, which would be expected to reduce the oil yield, but higher pressure reduced the risk of reservoir plugging, so that the observed oil yield was higher at higher pressure. Numerical simulations revealed distinct pyrolysis kinetics under high pressure compared to atmospheric conditions, showing elevated activation energy and reduced conversion rates with pressure increase. During high-temperature nitrogen injection, cumulative oil production and energy efficiency decreased under higher pressures. Consequently, the simulation indicates that excessive pressure inhibits the effectiveness of convection.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109940"},"PeriodicalIF":4.9,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143844058","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 louver-perforated V-type baffles on thermal effectiveness and entropy in round tube","authors":"Pongjet Promvonge ,&nbsp;Somchai Sripattanapipat ,&nbsp;Maturose Suchatawat ,&nbsp;Mahdi Erfanian Nakhchi ,&nbsp;Sompol Skullong","doi":"10.1016/j.ijthermalsci.2025.109939","DOIUrl":"10.1016/j.ijthermalsci.2025.109939","url":null,"abstract":"<div><div>An experimental investigation was conducted to assess the influence of insertion of a louver-perforated V-type baffle (LVB) vortex generator into a consistent heat-fluxed tube on thermal performance. This study aimed to optimize thermal effectiveness to boost energy savings and reduce the heat exchanger size. The experiments focused on investigating the thermal features, as well as estimating the entropy of turbulent flow at Reynolds numbers (Re) varying between 4750 and 29,290. The LVBs were positioned in two different arrays on a supporting tape during the present experiment: \"V-down\" and \"V-up,\" with the V-apex oriented upstream and downstream, respectively, at a fixed attack angle (<span><math><mrow><mi>α</mi></mrow></math></span> = 52°). At one relative baffle height (B_R = 0.3) and pitch (P_R = 1.0), the LVBs dealt with six louver flapped angles (<span><math><mrow><mi>θ</mi></mrow></math></span> = 0°, 10°, 20°, 30°, 45°, and 90°) in addition to three louver-hole sizes and locations (<em>θ</em>₁, <em>θ</em>₂ and <em>θ</em>₁₂). Comparative analysis was also conducted on data obtained from the current smooth tube. According to the findings, the louver angle <span><math><mrow><msub><mi>θ</mi><mn>1</mn></msub></mrow></math></span> = 20°, located on the baffle's trailing end, had the greatest relative Nusselt number (Nu_R), which was 5.9 times for V-down and 6.38 times for V-up. Furthermore, compared to the V-down and V-up solid baffles (<span><math><mrow><mi>θ</mi></mrow></math></span> = 0°), their friction losses were lessened. The V-up LVB reached its minimum value at <span><math><mrow><msub><mi>θ</mi><mn>1</mn></msub></mrow></math></span> = 20°, corresponding to the lowest Re. At <span><math><mrow><msub><mi>θ</mi><mn>1</mn></msub></mrow></math></span> = 20°, the V-up LVB attained its minimum entropy generation (<span><math><mrow><msubsup><mover><mi>S</mi><mo>˙</mo></mover><mrow><mi>g</mi><mi>e</mi><mi>n</mi></mrow><mo>′</mo></msubsup></mrow></math></span>) and maximum reduced entropy factor (<em>S</em>_R) around 20.3. At a comparable <span><math><mrow><msub><mi>θ</mi><mn>1</mn></msub></mrow></math></span> = 20°, the maximal thermal effectiveness factor (TEF) of V-down and V-up were approximately 2.39 and 2.59, respectively. The estimation and documentation of correlations were also performed for the parameters under consideration, namely <em>Nu</em>, <em>f</em>, and TEF.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109939"},"PeriodicalIF":4.9,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143835200","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":"Numerical simulation of a novel composite microchannel for large-scale THz phased array antennas thermal management","authors":"Zhengpeng Chen ,&nbsp;Bo Yuan ,&nbsp;Jie Yang ,&nbsp;Zhuo Zhang ,&nbsp;Yuqi Tang ,&nbsp;Yang Yang ,&nbsp;Hansheng Zheng ,&nbsp;Yong Chen","doi":"10.1016/j.ijthermalsci.2025.109924","DOIUrl":"10.1016/j.ijthermalsci.2025.109924","url":null,"abstract":"<div><div>As terahertz (THz) phased arrays antennas (PAA) scale up, the accompanying increase in power density and heat generation poses significant challenges for thermal management. The aim of this work is to explore effective solutions for achieving an ideal uniform temperature distribution and lower peak temperature in the context of large-scale small heat sources. Considering the high-efficiency heat transfer and surface temperature uniformity of microchannel heat sinks, this paper proposes a novel composite microchannel heat sink structure based on traditional microchannel heat sinks. Using peak temperature, pressure drop, temperature uniformity, thermal stress, and thermal deformation as key indicators, a comprehensive numerical simulation analysis of the novel composite microchannel heat sink and traditional microchannel heat sinks under different Reynolds numbers (<span><math><mrow><mi>R</mi><mi>e</mi></mrow></math></span>) were conducted based on computational fluid dynamics (CFD) and elasticity mechanics. The results show that the novel composite microchannel heat sink exhibits superior fluid flow and heat transfer performance with better temperature uniformity. At <span><math><mrow><mi>R</mi><mi>e</mi><mo>=</mo><mn>1500</mn></mrow></math></span>, it achieves improvements of 11.2 %, 9.2 %, 14.6 %, and 8.2 % compared to the traditional microchannel heat sinks. Moreover, it can achieve the same peak temperature as traditional microchannel heat sinks with lower pumping power. Furthermore, it was found that the novel composite microchannel heat sink can effectively reduce the pressure drop in microfluidic systems. At <span><math><mrow><mi>R</mi><mi>e</mi><mo>=</mo><mn>1500</mn></mrow></math></span>, the pressure drop is reduced by 37.5 %, 39 %, 31.9 %, and 35.6 % compared to the corresponding traditional microchannel heat sink. Overall, the novel composite microchannel heat sink outperforms traditional microchannel heat sinks in both flow characteristics and temperature uniformity.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"214 ","pages":"Article 109924"},"PeriodicalIF":4.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143828488","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}