International Journal of Thermal Sciences最新文献

{"title":"Transport phenomena during solidification and melting of water: Experimental and numerical studies","authors":"Radhika Sarawagi,&nbsp;Abhishek Kumar Singh,&nbsp;Virkeshwar Kumar","doi":"10.1016/j.ijthermalsci.2025.110119","DOIUrl":"10.1016/j.ijthermalsci.2025.110119","url":null,"abstract":"<div><div>Understanding water solidification and melting is crucial for optimizing water-based thermal energy storage systems and designing containers that accommodate ice expansion without structural damage. This study uses experiments and numerical simulations to investigate the shape of the solid-liquid interface, thermal history, velocity distribution, and solid fraction of water during successive solidification and melting processes. PIV (Particle image velocimetry), shadowgraph, and DSLR imaging are used to capture the flow pattern and solid-liquid interface during the phase change process. Eight thermocouples were placed inside the cuboidal cell to collect temperature data, which was subsequently compared with results from Fluent simulations.</div><div>Based on thermal data, the solidification process is divided into three distinct regimes: convective dominant, constant temperature, and solidifying. Flow behaviors are analyzed using the simulation velocity field, experimental velocity field, and thermal Rayleigh number. The simulation reported the maximum height of ice during expansion for different aspect ratios. The melting process revealed complex convective flow patterns, including side convection, Rayleigh-Bénard convection near the bottom region, air convection in the upper sections, and ice toppling, causing temperature fluctuations in a zig-zag pattern through experiments. Numerical simulations showed similar trends to experimental results but differed in specific temperature values and behaviors, particularly during melting. The simulation indicated that melting occurs through convective flows, while experimental observations highlighted additional factors such as mixing, melting water, ice movement, and varying convective patterns. This research provides a comprehensive understanding of water's solidification and melting behavior using experiments and numerical simulations, which shows the role of convection.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"218 ","pages":"Article 110119"},"PeriodicalIF":4.9,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522900","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":"An inverse prediction and experimental study for the internal insulator boundary conditions of solid rocket motor","authors":"Shashi Liu ,&nbsp;Wenbin Li ,&nbsp;Xuefan Hao ,&nbsp;Xiao Hou ,&nbsp;Xiping Feng","doi":"10.1016/j.ijthermalsci.2025.110096","DOIUrl":"10.1016/j.ijthermalsci.2025.110096","url":null,"abstract":"<div><div>This paper primarily estimates the boundary conditions of the ablative insulation structure within a solid rocket motor and proposes a non-contact measurement method to mitigate the impact of thermal perturbations and slag deposition on measurement results. The thermal boundary conditions in the combustion chamber severely restrict the refined design of insulation structures. Due to the strong nonlinearity of the heat conduction system caused by the harsh thermal environment, reducing the ill-posedness of the nonlinear inverse problem in non-contact boundary condition measurement has always been a challenge. In this study, a model for solving the nonlinear inverse problem is developed using Physics-Informed Neural Networks (PINNs) and automatic differentiation. Compared to regularization methods, the proposed algorithm reduces the condition number to its square root. Numerical simulations and quartz lamp heating tests show that the algorithm remains stable and robust against noise pollution from thermocouples and data acquisition systems. The method is applied to high overload conditions of a solid rocket motor, successfully measuring the boundary conditions inside the combustion chamber. The obtained data is validated and analyzed through comparison with contact method and numerical simulations to ensure its reliability and rationality.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"218 ","pages":"Article 110096"},"PeriodicalIF":4.9,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522899","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":"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":"Beyond single-pipe paradigm: conjugate heat transfer modeling reveals developed heat transfer correlation for concentric-pipe in artificial ground freezing","authors":"Wang Wu ,&nbsp;Qixiang Yan ,&nbsp;Junchen Zhang ,&nbsp;Zhaowei Ding","doi":"10.1016/j.ijthermalsci.2025.110123","DOIUrl":"10.1016/j.ijthermalsci.2025.110123","url":null,"abstract":"<div><div>The artificial ground freezing (AGF) method is an effective reinforcement technique in water-rich and weak strata. In the numerical simulation of AGF temperature fields, scholars typically assume convection heat transfer or fixed temperature boundaries at the surface of the freezing pipe. This simplification reduces modeling complexity by eliminating the need to simulate brine flow, thereby enhancing computational efficiency. For single-pipe, single-phase forced convection heat transfer, several well-established heat transfer correlations exist. However, in AGF applications, freezing pipes are often composed of two concentric pipes. Consequently, it is crucial to propose heat transfer correlations applicable within these concentric pipes. In this study, based on single-pipe heat transfer correlations, a convective heat transfer model is established to validate the single-pipe conjugate heat transfer model. Subsequently, a conjugate heat transfer model for concentric pipes is also developed. Results indicate that the single-pipe heat transfer correlation is not suitable for concentric pipes, with 7 points exhibiting temperature differences exceeding 0.6 °C, among which the maximum reached 0.86 °C. Based on classical heat transfer correlations, a new correlation for the annular space is proposed, demonstrating excellent agreement with most temperature differences controlled within 0.2 °C. Further comparison with the model tests shows that the results are also in good agreement under different flow rates, freezing pipe sizes, and freezing durations. This study provides significant reference value for more accurate investigations of the AGF process using numerical simulation methods.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"217 ","pages":"Article 110123"},"PeriodicalIF":4.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144523675","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}