{"title":"Buffering heat fluctuation of IGBT power electronic modules using phase change material-based thermal management for wind power generation","authors":"Shuai Zhang, Yuying Yan","doi":"10.1016/j.ijheatmasstransfer.2025.127903","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.127903","url":null,"abstract":"<div><div>The insulated-gate bipolar transistor (IGBT) power electronic module is an essential component of the converter system for wind power generation. However, it suffers from the heat fluctuation induced by transient output power from the wind turbulence, which makes it vulnerable and easy to fail. In this study, we developed a phase change material (PCM)-based thermal management solution whose structure is simple and does not change the existing heat sinks. PCM absorbs most heat when the power loss surges, but its temperature stays stable owing to the solid-liquid phase transition. That reduces the peak junction temperature, and since the decrease in peak temperature is larger than that in the valley temperature, the heat fluctuation of chips is buffered. This solution decreases heat fluctuation by 8.7 °C at most and has the best buffering performance where heat fluctuation is largest. The melting fraction of PCM does not exceed 1 during the thermal management process, indicating that the PCM can work sustainably. Different types of PCM were examined, and the results indicate that PCM2’s melting fraction responds more sensitively to power loss and absorbs more power loss as the latent heat energy, thus has better buffering performance than PCM1. The lifetime of the IGBT module is also predicted and is extended significantly. The PCM-based thermal management solution developed in this study is a promising approach to improve the robustness and reduce the maintenance cost of the IGBT modules in wind power generation.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127903"},"PeriodicalIF":5.8,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216983","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 analysis of the effect of stationary laser beam properties on Al-Si coating mixing in 22MnB5 steel","authors":"Emanuele Fulco , Donato Coviello , Donato Sorgente","doi":"10.1016/j.ijheatmasstransfer.2025.127899","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.127899","url":null,"abstract":"<div><div>This study presents a numerical investigation of molten pool dynamics and coating material mixing under stationary laser irradiation, using a computational fluid dynamics (CFD) model to analyse contamination effects and the resulting melt pool geometry with a fixed laser beam relative to the workpiece. The model considers a 1.6 mm-thick 22MnB5 steel coated on both sides with a 30 µm-thick Al-Si coating. A grid independency analysis, performed with mesh sizes from 15 µm to 120 µm, showed that mesh sizes at least matching the Al-Si coating thickness are required for accurate representation of fluid dynamics and contamination effects in terms of average Al content and volume percentage of the fused zone contaminated by the coating material. A numerical investigation was carried out to evaluate how variations in laser beam waist radius (0.225, 0.3, and 0.375 mm) and defocusing distance (-0.8 mm, 0, and +0.8 mm) influence the melt pool geometry and the Al-Si coating contamination in 22MnB5 steel. Results indicated that, under positive defocusing conditions, a larger beam waist radius, that is the radius of the laser beam at the focal point, favoured the formation of a <em>Y-shaped</em> keyhole geometry and contributed to lower Al-Si contamination levels in the melt pool. Higher contamination levels were observed in the simulations with a beam waist radius of 0.225 mm, compared to the cases with 0.3 mm and 0.375 mm, indicating an inverse relationship between beam waist radius and coating contamination.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127899"},"PeriodicalIF":5.8,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216984","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}
Lige Zhang , Tejaswi Soori , Manohar Bongarala , Changgen Li , Han Hu , Justin A Weibel , Ying Sun
{"title":"Generalizable physical descriptors of pool boiling heat transfer from unsupervised learning of images","authors":"Lige Zhang , Tejaswi Soori , Manohar Bongarala , Changgen Li , Han Hu , Justin A Weibel , Ying Sun","doi":"10.1016/j.ijheatmasstransfer.2025.127894","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.127894","url":null,"abstract":"<div><div>Boiling processes are notoriously difficult to analyze via visual inspection due to the complex interactions between the vapor bubbles and the surface. Unsupervised machine learning (ML) is a powerful tool to uncover physical insights into the bubble dynamics during boiling from image data. In this study, principal component analysis (PCA), an unsupervised dimensionality reduction algorithm, is used to extract new physical descriptors of boiling heat transfer from pool boiling experimental images without any labeling and training. Experiments are conducted with different working fluids and heater surfaces to investigate the effect on the bubble morphology and subsequently on the physical descriptors identified through unsupervised ML. The dominant frequency and amplitude deduced from the Fourier transform of the time series of the first principal component (PC) are compared against physical parameters such as bubble size, bubble count, and vapor area fraction. The new physical descriptors derived from PCA show a positive correlation with conventional parameters related to bubble morphology, as demonstrated by linear regression analysis. Pearson Correlation Coefficients further confirm the strong correlations between dominant amplitude and both bubble size and vapor area fraction, as well as between dominant frequency and bubble count. These strong correlations hold across multiple different working fluids (water and HFE 7100) with different heater surfaces (plain and microstructured surfaces made of copper and silicon materials), demonstrating the potential for these extracted physical descriptors to generalize and act as a surrogate to conventional physical descriptors. This unsupervised learning approach offers a robust alternative to traditional pool boiling analyses or supervised ML approaches that rely on time-consuming manual labeling involving bubble identification and segmentation.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127894"},"PeriodicalIF":5.8,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216985","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":"Design and intelligent optimization of TSV-based embedded microchannel heatsinks in 2.5D Packaging","authors":"Dongqing Cang , Zixuan Dong , Shitao Lv , Chencan Zhou , Zhikuang Cai , Peng Zhang , Haiyan Sun , Jicong Zhao","doi":"10.1016/j.ijheatmasstransfer.2025.127908","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.127908","url":null,"abstract":"<div><div>With the continuous advancement of integrated circuits, chip density and miniaturization have increased significantly, resulting in a substantial rise in on-chip temperatures. Customized thermal management strategies tailored to different chiplet packaging configurations have become crucial. At present, microchannel heatsinks (MCHS) are widely employed to improve heat dissipation in multi-chiplets packaging. In order to improve the heat dissipation capability of multi-chiplets packaging, embedded MCHS has been extensively studied in recent years. However, embedded MCHS will inevitably affect the routing within the interposer. In this study, we propose an innovative heat dissipation approach that integrates MCHS within TSV(Through-Silicon-Via) interposer. By embedding TSV into the walls of the MCHS, this method significantly enhances heat dissipation while maintaining routing integrity. The novel structure in this study is defined as T-MCHS. Firstly, we verified that the proposed design exhibits better heat dissipation capability and a higher friction factor compared to the traditional structure. Subsequently, the structure is optimized using an enhanced NSGA-II (Nondominated Sorting Genetic Algorithm II) algorithm. To enhance computational efficiency, the simulation model is simplified during the optimization process, and an ANN(Artificial Neural Network) surrogate model is constructed based on simulation data to replace time-consuming simulations, thereby enhancing optimization efficiency. Finally, performance validation is conducted through extensive simulations. The optimized T-MCHS demonstrated significantly enhanced heat dissipation performance while effectively reducing pumping power. Compared to other jobs, this design is able to achieve a greater convective heat transfer coefficient by sacrificing less pumping power. Additionally, stress uniformity across the substrate is improved, contributing to a significant enhancement in overall reliability.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127908"},"PeriodicalIF":5.8,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216986","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":"A detailed numerical investigation on evaporation and combustion of isolated n-heptane and n-dodecane droplet in argon-oxygen atmosphere","authors":"Surya Balusamy, Ki Yong Lee","doi":"10.1016/j.ijheatmasstransfer.2025.127895","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.127895","url":null,"abstract":"<div><div>This paper presents a comprehensive numerical framework for simulating the evaporation and combustion of isolated fuel droplets using the Lagrangian–Eulerian method in a three-dimensional computational domain. The study has been carried out in two phases, evaporation and combustion. For evaporation, the effect of temperature, pressure, gravity and inert gas as ambient gas is numerically investigated. The numerical results of the squared normalized droplet diameter <span><math><msup><mrow><mrow><mo>(</mo><mi>d</mi><mo>/</mo><msub><mrow><mi>d</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>)</mo></mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span> with respect to time (<span><math><mrow><mi>t</mi><mo>/</mo><msubsup><mrow><mi>d</mi></mrow><mrow><mn>0</mn></mrow><mrow><mn>2</mn></mrow></msubsup></mrow></math></span>) were compared with the experimental data of other researchers and showed good agreement. The numerical simulation was performed for the combustion of isolated <em>n</em>-heptane and <em>n</em>-dodecane with the initial droplet diameter of <span><math><mrow><mn>0</mn><mo>.</mo><mn>05</mn><mspace></mspace><mtext>mm</mtext></mrow></math></span> and the ambient temperature (<span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>a</mi></mrow></msub></math></span>) in the range of <span><math><mrow><mn>750</mn><mi>K</mi><mo>−</mo><mn>1000</mn><mi>K</mi></mrow></math></span> and ambient pressure (<span><math><msub><mrow><mi>P</mi></mrow><mrow><mi>a</mi></mrow></msub></math></span>) of <span><math><mrow><mn>2</mn><mi>M</mi><mi>P</mi><mi>a</mi><mo>−</mo><mn>3</mn><mi>M</mi><mi>P</mi><mi>a</mi></mrow></math></span>. This study investigated the two-stage ignition process and the effect of argon-oxygen mixture as ambient gas on the auto-ignition delay time for <em>n</em>-heptane and <em>n</em>-dodecane fuel droplet. A detailed kinetic mechanism (DKM) and the perfectly stirred reactor (PSR) model were utilized to analyze the effect of ambient gases of air (AG-1) and argon-oxygen mixture (AG-2). The results showed that cases using AG-2 as the ambient gas exhibited a stronger cool flame and an increased auto-ignition delay time at moderate ambient temperatures (<span><math><mrow><msub><mrow><mi>T</mi></mrow><mrow><mi>a</mi></mrow></msub><mo>=</mo><mn>800</mn><mo>−</mo><mn>850</mn><mspace></mspace><mi>K</mi></mrow></math></span>) compared to AG-1. Conversely, the auto-ignition delay time was decreased at elevated ambient temperatures <span><math><mrow><mo>(</mo><msub><mrow><mi>T</mi></mrow><mrow><mi>a</mi></mrow></msub><mo>></mo><mo>=</mo><mn>900</mn><mi>K</mi><mo>)</mo></mrow></math></span>.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127895"},"PeriodicalIF":5.8,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216925","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":"Spatio-temporal scale matching for grooved cooling channel under pulsating flow","authors":"Yingting Tang, Zhaoguang Wang","doi":"10.1016/j.ijheatmasstransfer.2025.127883","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.127883","url":null,"abstract":"<div><div>The present study numerically and experimentally characterizes the heat transfer performance of a grooved channel under pulsating flow, with Strouhal number ranging from 0.04 to 0.8 and groove depth ratio between 1/4 and 1. The time-averaged Reynolds number of the trapezoidal pulsation profile is maintained at 200 and the temporal maximum is limited at 1000. The augmentation of heat transfer is attributed to both enhancement in flow convection intensity and improvement of thermal mixing efficiency. The former is illustrated by the asymmetry of kinetic energy change that arises from the loss of complementarity between wall shear stress and viscous entropy generation. The latter is explained by the reboost of thermal entropy generation that results from the transverse mixing between near-wall hot fluids and mainstream coolant. There exist significant phase lags and waveform distortion between the channel Nusselt number and the inlet velocity profile, indicating that the dominant mechanism for heat transfer enhancement transitions from mass convection at the pulse-on stage to thermal mixing at the pulse-off stage. Further scale-matching analysis reveals that the greatest Nusselt number improvement of 317% is obtained at the Strouhal number around 0.2 and the groove depth ratio of 1/2. With a penalty of 324% friction factor ratio, the thermal enhancement factor is still improved to 2.14. The optimal pulsation frequency that matches the characteristic time of cavity vortex growth and the optimal groove dimension that matches the characteristic size of cavity vortex expansion lead to the maximum kinetic energy residual and the minimum thermal entropy generation.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127883"},"PeriodicalIF":5.8,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216988","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}
Haijie Chang , Yabo Jia , Hans Boungomba , Hakim Naceur , Laurent Dubar
{"title":"Development of a predictive multi-material and multi-physics model based on volume-of-fluid for simulating wire laser additive manufacturing process","authors":"Haijie Chang , Yabo Jia , Hans Boungomba , Hakim Naceur , Laurent Dubar","doi":"10.1016/j.ijheatmasstransfer.2025.127893","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.127893","url":null,"abstract":"<div><div>Wire Laser Additive Manufacturing (WLAM) has been widely applied in production technologies for creation of complex geometry and repairing. This process involves numerous coupled physical phenomena, such as laser-material interaction, phase transformations (solid and liquid), fluid dynamics within the melt pool, and heat transfer, making it extremely complex to analyze and observe experimentally. Recently, the use of a wire made from a metal different from the substrate has gained in popularity to create functionally graded material. This approach is particularly attractive for adding new functionalities to existing parts or enhancing surface mechanical properties. However, the numerical simulation of the multi-material WLAM process presents significant challenges due to the differences in the thermophysical properties of different metals. To address this challenge, we present a predictive multi-physics solver developed within the OpenFOAM software based on the volume-of-fluid (VOF) method. The solver considers the conservation of momentum, energy, and mass, the mixture of multiple material, ray-tracing, and heat exchange with air to simulate the multi-material WLAM process. Finally, the proposed model has been validated against the numerical reference and experimental results, the comparisons show the proposed model is capable of predicting the bead geometry for different process parameters without calibration of the heat source or mass addition.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127893"},"PeriodicalIF":5.8,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216982","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}
Ting Hu , Zhencheng Zhao , Lulu Xu , Haiyang Deng , Xinzhuo Wang , Zhenhua Rui , Mabrouk Sami , Huazhou Li
{"title":"Multiscale experimental-numerical investigation of CO2 transport and phase evolution in carbonate reservoirs","authors":"Ting Hu , Zhencheng Zhao , Lulu Xu , Haiyang Deng , Xinzhuo Wang , Zhenhua Rui , Mabrouk Sami , Huazhou Li","doi":"10.1016/j.ijheatmasstransfer.2025.127870","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.127870","url":null,"abstract":"<div><div>Geochemical intensifications coupled with multiphase seepage in highly heterogeneous porous media are the main factors for CO<sub>2</sub> transport and phase evolution in carbonate reservoirs. This study establishes a mechanistic model incorporating geochemical reactions and fracture-cavern media to examine how these factors influence CO<sub>2</sub> transport and phase evolution. Intensified chemical reactions in carbonate reservoir promote CO<sub>2</sub> dissolution in aqueous and particularly in oil phases, contributing to enhanced oil recovery to some extent. Fractures parallel to the connection line between injection and production wells serve as high-permeability channels along which fluids preferentially flow, reducing the sweep efficiency of CO<sub>2</sub>. In contrast, the vertical fracture is beneficial to lateral fluid flow. High-velocity fluid and high reactive specific surface area in fractures induce more prominently geochemical reactions. However, mineral chemical reactions occur on the fracture surfaces, resulting in a fracture plugging effect during the CO<sub>2</sub> sequestration phase. Mineral precipitation forms a physical barrier on the fracture surfaces, leading to hindered fluid migration and restricted reaction areas. For the fracture-cavern media, timely repositioning of CO<sub>2</sub> injection wells can significantly enhance oil recovery efficiency. Injection rate is a key synergistic parameter for storage and recovery in fracture-cavern carbonate reservoir. Dolomitization (CaMg(CO<sub>3</sub>)<sub>2</sub>) is the primary mechanism facilitating mineralization in carbonate reservoirs, which not only enhances permeability but also enables greater CO<sub>2</sub> mineralization compared to calcite (CaCO<sub>3</sub>) precipitation. These findings demonstrate the potential of geochemical intensification to enhance CO<sub>2</sub> storage and utilization efficiency.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127870"},"PeriodicalIF":5.8,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216987","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":"Curvature-enhanced thermal radiation in micro-structure","authors":"Binghe Xiao, Yimin Xuan","doi":"10.1016/j.ijheatmasstransfer.2025.127898","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.127898","url":null,"abstract":"<div><div>Thermal radiation management is important in various micro-systems, such as integrated photonic design, thermal logic computing and energy harvesting, but the curvature effect of micro-structures on thermal radiation almost remains elusive. In this work, the mechanism of curvature effects on radiation is studied from near-field to far-field based on concentric cylinders with fluctuation-dissipation theory (FDT). A general formula applied for anisotropic materials radiation is derived, with the SiO<sub>2</sub>-VO<sub>2</sub> system analyzed as an example. The effects of curvature on radiation are investigated with SPPs, SPhPs and Hyperbolic surface modes. In near field-condition where the gap is smaller than the radius on the order of the tunneling depth, surface with curvature can transfer more heat radiation than plane, both for inner and outer surface. Some surface wave modes suppressed in planar geometries are activated in micro-cylindrical structures. Also, structure curvature enhances radiation in the far-field, enabling super-blackbody radiation in some cases. The results above are analyzed from the perspective that oscillators have more opportunity to radiate energy away from the curved structure. Lastly, the enhancement mechanism studied above is applied to thermal rectification with cylindrical configuration, the max rectification ratio can be up to 22 in GST-SiO<sub>2</sub> system, achieving an order-of-magnitude enhancement compared the ratio of 2 in planer structure. This work provides a further insight to thermal management in micro-systems.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127898"},"PeriodicalIF":5.8,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216926","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":"Pore-scale numerical investigation of water–gas flow and heat transport in gas diffusion layers with varying fiber/additive content and hydrophobicity","authors":"Danan Yang, Martin Andersson, Himani Garg","doi":"10.1016/j.ijheatmasstransfer.2025.127859","DOIUrl":"10.1016/j.ijheatmasstransfer.2025.127859","url":null,"abstract":"<div><div>Additives such as binders and hydrophobic agents are commonly introduced into the fibrous Gas Diffusion Layer (GDL) of proton exchange membrane fuel cells to enhance mechanical strength and facilitate water management. However, the effect of additive/fiber content and surface wettability on water removal, oxygen diffusion, and heat conduction remains insufficiently understood. In this work, we develop a stochastic GDL reconstruction framework with systematically varied fiber and additive content. The reconstructed structures are analyzed through pore–throat network extraction, interface-resolved two-phase flow simulations, as well as oxygen diffusion and heat conduction simulations under dry and partially saturated conditions. The variation in surface wettability caused by the coating of hydrophobic additives is simulated by the contact angle. The results reveal that increased fiber content significantly restricts pore space, thereby weakening oxygen diffusivity and increasing breakthrough pressure, while having a limited impact on stabilized water saturation and thermal conductivity. Additives, particularly at high loadings, reduce pore connectivity and gas transport, though enhanced hydrophobicity partially mitigates these effects. Oxygen diffusivity is found to be particularly sensitive to changes in effective pore space caused by additive inclusion and water occupation. These findings present a comprehensive quantitative perspective on how additive design modulates GDL transport properties and provide a simulation-based framework for optimizing fuel cell GDL microstructure.</div></div>","PeriodicalId":336,"journal":{"name":"International Journal of Heat and Mass Transfer","volume":"255 ","pages":"Article 127859"},"PeriodicalIF":5.8,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145216865","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}