International Journal of Thermal Sciences最新文献

{"title":"Validation of a parietal heat transfer model in a constant volume spherical vessel","authors":"Taïssir Kasraoui ,&nbsp;Karl Joulain ,&nbsp;Rémi Bertossi","doi":"10.1016/j.ijthermalsci.2025.110082","DOIUrl":"10.1016/j.ijthermalsci.2025.110082","url":null,"abstract":"<div><div>This work aims to numerically estimate the parietal heat flux in various thermal systems, such as the spherical combustion chamber at constant volume. We estimate mainly the convective heat coefficient using a new approach based on the kinetic theory of gas instead of existing macroscopic models. In this configuration, which is marked by high pressures and temperatures, assessing the wall heat flux presents an important challenge. This study employs a transient heat transfer model derived from an innovative application of kinetic theory of gases to elucidate conduction phenomena between gas particles and a cold wall at short scales. We want to analyze and evaluate heat exchange at the wall by modeling the interactions between the flame and the wall, as well as the burned gas and the wall, using an unsteady thermal transfer model implemented in FORTRAN code. Numerical results of time evolution of pressure and heat flux in different operating conditions were illustrated and compared to the experimental ones to validate the approach.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110082"},"PeriodicalIF":4.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517056","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":"Analytical heat transfer model of energy piles in layered and anisotropic soils considering interfacial thermal resistance","authors":"Qingkai Zhang ,&nbsp;Xiangyun Zhou ,&nbsp;De'an Sun ,&nbsp;You Gao ,&nbsp;Minjie Wen ,&nbsp;Shixiang Hu ,&nbsp;Nina Gong","doi":"10.1016/j.ijthermalsci.2025.110115","DOIUrl":"10.1016/j.ijthermalsci.2025.110115","url":null,"abstract":"<div><div>The energy pile, as an innovative renewable energy system integrating ground source heat pump technology with pile foundation structures, exhibits thermal performance that is significantly influenced by complex soil conditions. To address the complications in heat transfer mechanisms caused by the layered characteristics of natural soils and their cross-anisotropy, this study develops a heat transfer model for energy piles embedded in layered and cross-anisotropic soils while accounting for interfacial thermal resistance. A semi-analytical solution in the Laplace domain is derived using the finite Hankel transform and Laplace transform, and the temperature response in the time domain is obtained via the Crump numerical inversion method. Comparative validation against COMSOL numerical solutions, classical analytical solutions, and experimental data demonstrates that the temperature prediction error of the proposed model remains below 2.1 % relative to numerical solutions. Compared to experimental measurements, the root-mean-square error (RMSE) is reduced by more than 42 % compared to conventional isotropic models. The near-field temperature response analysis reveals that the horizontal and vertical thermal conductivities of the soil exhibit distinctly different influences on the temperature distribution, with the horizontal thermal conductivity of the pile body playing a more dominant role in soil temperature response. Using an equivalent average thermal conductivity leads to deviations in temperature predictions. Parametric study indicates that the variations in the horizontal and vertical thermal conductivity of the soil have different impacts on temperature. In addition, the thermal anisotropy ratio (TAR) and interlayer thermal conductivity ratio (ITCR) significantly influence the interfacial temperature jump. Furthermore, under different thermal conductivity conditions, the effect of changes in the thermal anisotropy ratio on the temperature jump also varies.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110115"},"PeriodicalIF":4.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517057","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 investigation of the effects of current and voltage on the thermal characteristics of low-voltage DC fault arc","authors":"Chaoying Li,&nbsp;Zehua Yang,&nbsp;Wenbin Yao,&nbsp;Haidong Liu,&nbsp;Jin Lin,&nbsp;Shouxiang Lu","doi":"10.1016/j.ijthermalsci.2025.110122","DOIUrl":"10.1016/j.ijthermalsci.2025.110122","url":null,"abstract":"<div><div>Fault arc is one of the potential causes of electrical fires. To predict the thermal characteristics of long-duration fault arcs in low-voltage DC systems, this study conducted a series of fault arc experiments under different initial current and power supply voltage conditions. The results indicate that the arc ignition process for the copper-copper electrodes follows the sequence: break arc, arc heating electrode, electrode melting, and arc extinction. The melting and dripping speed of the copper electrode tip is influenced by arc power, and in some high-power arc cases, heat transfer to the electrode does not reach a stable state before arc extinction, thus the electrode temperature does not always scale with arc power. By analyzing the arc power and arc duration based on the volt-ampere characteristics of the arc and its heat transfer characteristics to the electrodes, it was found that while an increase in initial current and power supply voltage enhances arc power, it also accelerates electrode consumption, thereby shortening the arc duration. The combined application of the arc power model and arc duration model established in this study enables effective prediction of arc energy. The research findings provide guidance for fault arc prevention in low-voltage DC electrical systems.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110122"},"PeriodicalIF":4.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517055","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 of the effect of storage tank boundary conditions on crude oil boilover fires","authors":"Yueyang Li ,&nbsp;Mingze Li ,&nbsp;Guohua Luan ,&nbsp;Qi Jing ,&nbsp;Xin Li ,&nbsp;Yuntao Li ,&nbsp;Laibin Zhang","doi":"10.1016/j.ijthermalsci.2025.110118","DOIUrl":"10.1016/j.ijthermalsci.2025.110118","url":null,"abstract":"<div><div>Water present at the bottom of crude oil storage tanks can lead to boilover phenomena during a fire, posing significant hazards. As the vessel containing crude oil, understanding the impact of tank boundary conditions on boilover provides theoretical support for tank design. This study investigates the effects of tank opening size, wall conditions, and dimensions through a series of experiments. The results show that reducing the tank opening size initially promotes, then inhibits combustion. When the opening is sufficiently small, the hot zone disappears, delaying the boilover onset time from 43.62 min to 130.35 min. The tank wall conditions significantly influence boilover behavior. When an interlayer is added to the tank wall and filled with air, it provides thermal insulation, reducing the boilover onset time to 40 % of that in an ordinary tank, while increasing the hot wave propagation rate by 1.5 times. When the interlayer is filled with static or flowing water, the formation of the hot zone is suppressed and no boilover occurs. The study shows that as tank diameter increases, boilover ejection intensity decreases, boilover onset time shortens (<span><math><mrow><msub><mi>t</mi><mi>b</mi></msub><mo>∝</mo><mfrac><mn>1</mn><msqrt><mi>D</mi></msqrt></mfrac></mrow></math></span>), and hot wave propagation rate increases before stabilizing. A theoretical model for hot wave propagation is derived from the energy conservation equation. A set of large-scale (<em>D</em>:1.5m) comparison experiments is conducted, and it is found that the hot zone temperature remains constant in the radial direction, but the hot zone temperature decreases instead of increasing compared to the small-scale experiments. For cases where smoke obscures the flame, a method for estimating the maximum flame height during the boiling period based on the solid flame radiation model is proposed. The results of the study help provide guidance for fire protection design and firefighting strategies in storage tanks.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110118"},"PeriodicalIF":4.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517054","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":"Impact of structural parameters on thermal performance of phase change thermal storage device based on flat plate micro heat pipe","authors":"Gang Wang ,&nbsp;Runfa Ye ,&nbsp;Wan Yu ,&nbsp;Zhenhua Quan ,&nbsp;Yonglian Chen","doi":"10.1016/j.ijthermalsci.2025.110116","DOIUrl":"10.1016/j.ijthermalsci.2025.110116","url":null,"abstract":"<div><div>Phase change energy storage technology utilizes the state transition of phase change materials (PCMs) to store and release energy, offering advantages such as high energy storage density and operational efficiency. Nevertheless, practical applications still exist challenges including uneven temperature distribution and suboptimal thermal efficiency. To enhance the thermal performance of thermal storage devices (TSD), this study develops a configuration employing flat plate micro heat pipes (FPMHPs) and rectangular fins as primary heat transfer components. The thermal performance is significantly influenced by several key design parameters, including the heat pipe distribution, the structural configuration of the shell surface, as well as the geometric characteristics of the fins—specifically their arrangement, width, thickness, and spacing. The results reveal the following key findings: (1) The system achieved optimal thermal performance at a heat pipe distribution parameter of N = 1.5. (2) A shell configuration with L = 15 reduced the PCM melting time by 8.69 % compared to that of conventional shell designs. (3) While increasing fin thickness showed marginal improvements, expanding the fin width from 40 mm to 60 mm significantly decreases the melting duration by 41.67 % enhanced energy storage capacity by 43.2 %. (4) Reducing the fin spacing from 9 mm to 5.6 mm shortened melting time by 34.76 % and increased the stored energy by 1.54 %. These findings will provide essential data-driven insights and a robust theoretical foundation for the optimization of TSD performance.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110116"},"PeriodicalIF":4.9,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514210","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":"Optimizing high-concentrator photovoltaic efficiency: Numerical study of hybrid nanofluid and porous wavy walled mini channel heat sink","authors":"Saeed Rabiei ,&nbsp;Raouf Khosravi ,&nbsp;Farid Varasteh ,&nbsp;Amin Etminan","doi":"10.1016/j.ijthermalsci.2025.110103","DOIUrl":"10.1016/j.ijthermalsci.2025.110103","url":null,"abstract":"<div><div>This study investigates advanced thermal management for high-concentration photovoltaic (HCPV) systems through the combined use of hybrid nanofluids and wavy-walled mini-channel heat sinks. Numerical simulations of 36 configurations, examining wave amplitudes (100–300 μm), Reynolds numbers (300–500), and nanoparticle concentrations (0–0.1 %wt) under a concentration ratio of 1200 and 1000 W/m² irradiance, demonstrate significant performance improvements. The optimal configuration achieves 41.15 % electrical efficiency and 224 W power output (i.e., 26 % higher than comparable systems) while maintaining exceptionally low pumping power (i.e., 0.007 W). Integrating wavy-walled channels with porous inserts yields substantial heat transfer enhancement by disrupting the boundary layer, promoting secondary vortices, and intensifying fluid-solid thermal interactions. This combined approach boosts thermal performance while markedly lowering the required pumping power. Artificial neural networks and genetic algorithms, successfully optimize the system by balancing electrical efficiency, temperature non-uniformity, and energy consumption. These findings provide a practical framework for implementing efficient cooling solutions in high-performance HCPV applications, offering technical advancements and sustainable energy benefits.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110103"},"PeriodicalIF":4.9,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514208","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":"Optimization of thermal noise propagation and mechanical properties at composite material interfaces","authors":"Xiangyu Liu ,&nbsp;Meng Liu ,&nbsp;Jiazhe Xu ,&nbsp;Qing Ai ,&nbsp;Yong Shuai","doi":"10.1016/j.ijthermalsci.2025.110106","DOIUrl":"10.1016/j.ijthermalsci.2025.110106","url":null,"abstract":"<div><div>This study investigated the propagation of thermal noise in composite material interfaces and the optimization of mechanical properties, focusing on applications in gravitational wave detection systems. Gravitational wave detection requires extremely high sensitivity, imposing strict demands on the propagation of thermal noise and temperature fluctuations in materials. The study analyzed the multi-interface structure of composite materials and its crucial role in temperature control and thermal noise transport, particularly examining the impact mechanisms of interfacial thermal resistance and conductivity. Through molecular dynamics simulations, the study revealed the regulatory effect of branched structures with varying numbers of monomers on heat conduction paths, demonstrating that thermal conductivity increased from 0.00384 W/(m·K) to 0.01645 W/(m·K), a 3.28-fold improvement. Additionally, the study analyzed the effect of interfacial heat source input on temperature distribution, finding that with a 0.2 W/m² input, the temperature distribution difference was within 35 %, while with a 0.2 GW/m² input, the difference reduced to 20 %. The study also explored the effect of monomer count in branched structures on the mechanical properties of materials, such as Young's modulus and shear modulus. The results indicated that the Young's modulus of the interface in the Z-direction increased by 152.89 % when the monomer count in the branches reached 13. The findings suggest that the rational design of interface structures can significantly optimize the thermal transport and mechanical properties of composite materials.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110106"},"PeriodicalIF":4.9,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514209","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 heat and flow transfer in permeable textile ensemble in windy conditions","authors":"Lexi Tu ,&nbsp;Xuanlin Qu ,&nbsp;Chong Heng ,&nbsp;Xiaomeng Jiang ,&nbsp;Jilong Wang ,&nbsp;Fumei Wang ,&nbsp;Hua Shen","doi":"10.1016/j.ijthermalsci.2025.110105","DOIUrl":"10.1016/j.ijthermalsci.2025.110105","url":null,"abstract":"<div><div>A three-dimensional geometric model of cold protective clothing was proposed, which consisted of a thin windproof layer and a thick insulation layer. The heat transfer and airflow movement within textile ensembles under different various conditions were simulated using a computational fluid dynamic (CFD) method. The simulation process considered natural convection occurring within the environment and the textile, as well as forced convection induced by the infiltration of ambient air into the textile. The effects of wind velocity, outer-layer permeability and inner-layer penetrability on thermal insulation properties of the textile ensembles were investigated. In addition, temperature distribution and airflow streamlines were utilized to examine the internal heat transfer and airflow movement mechanisms in windy conditions, with a particular focus on the interaction between multi-layer permeability and airflow. The finding indicated that reducing the permeability of the outer layer was found to advantageously minimize internal air movement and forced convection heat loss. In addition, in windy conditions, the thermal insulation of textiles with higher outer-layer permeability was dependent on the penetrability of the inner layer. Notably, combination textiles with a lower inner-layer permeability exhibited better thermal insulation performance compared to combination textiles with higher permeability. The obtained research findings offer a fresh perspective on cold protective clothing design, providing a theoretical foundation for optimizing clothing thermal performance by considering the interaction between different layers' permeability.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110105"},"PeriodicalIF":4.9,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144501229","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":"Development and experimental validation of a two-dimensional CFD model for narrow rectangular channel simulations","authors":"Hongquan Liu ,&nbsp;Yingwei Wu ,&nbsp;Chuan Lu ,&nbsp;Zhendong He ,&nbsp;Yanan He ,&nbsp;Wenxi Tian ,&nbsp;Suizheng Qiu","doi":"10.1016/j.ijthermalsci.2025.110114","DOIUrl":"10.1016/j.ijthermalsci.2025.110114","url":null,"abstract":"<div><div>The coolant flowing through the narrow rectangular channel delivers efficient cooling for the plate-type nuclear fuel assembly. These narrow rectangular channels are typically closed and differ significantly from the coolant channel geometry in conventional fuel rod assemblies. To accurately model the coolant behavior within these channels, a computational fluid dynamics (CFD) model was developed and validated in this paper. A two-dimensional (2D) mesh was employed to approximate the three-dimensional (3D) coolant flow, thereby reducing computational complexity. Conservation equations were formulated, and a void fraction model was incorporated as an auxiliary component. The model was validated by comparing calculation results with experimental data from the literature. In addition, to further investigate the coolant flow distribution, a multi-channel experiment was conducted to obtain additional validation data in this study. The verification results for the heat transfer, coolant flow, and void fraction models demonstrated satisfactory accuracy. The maximum absolute error of the coolant temperature was 3.1 K, and the pressure drop had a maximum relative error of 1.81 %. Under conditions of supercooled boiling at atmospheric pressure, the average relative error in void fraction was 18.24 %. Based on the multi-channel experimental data, the maximum relative error in flow distribution was 14.03 %. In multi-channel simulations, neglecting the heat conduction of steel partitions was identified as a significant source of error. Therefore, accurately modeling the coupled heat transfer between the steel partitions and the coolant is essential for improving simulation accuracy in future research.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110114"},"PeriodicalIF":4.9,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144501228","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":"Rapid non-invasive measurement of the time-dependent heat flux and temperature distribution in participating medium under non-Gaussian noise","authors":"Yang Hong,&nbsp;Yicheng Ma,&nbsp;Yifeng Wu,&nbsp;Shuangcheng Sun,&nbsp;Shuang Wen,&nbsp;Zhiqiang Sun","doi":"10.1016/j.ijthermalsci.2025.110112","DOIUrl":"10.1016/j.ijthermalsci.2025.110112","url":null,"abstract":"<div><div>The particle filter (PF) and extended particle filter (EPF) techniques are proposed to resolve the real-time estimated of the aerothermal heat flux and temperature fields of the thermal protection system (TPS) for the hypersonic vehicle. The TPS is regarded as a typical participating medium. The radiation heat transfer in the participating medium is computed by the Rosseland diffusion model. The finite volume method is utilized to solve the energy equation to obtain measurement temperature. Based on the measurement temperature signal, the Particle filtering technique is applied to reconstruct the surface heat flux and inner temperature field of the TPS. Four typical non-Gaussian noises are added to the simulated temperature signal to investigate the tracking ability and stability of the proposed algorithms. The influence of the measured noise, measured noised covariance, process noise covariance, time step, and number of the particle on the estimated results are discussed in detail. The calculated results indicate that even though the actual time-dependent heat flux measured by NASA is considered, an acceptable estimated result can still be obtained based on the EPF and PF techniques. The normalized root mean square errors of the actual heat flux reconstructed by PF and EPF are 5.45 % and 2.55 %, and the average relative errors of the reconstructed temperature field are 0.1 % and 0.043 %, respectively. All the estimation results illustrate that EPF technique has better tracking ability and robustness compare with the PF method.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110112"},"PeriodicalIF":4.9,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144491954","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}