International Communications in Heat and Mass Transfer最新文献

{"title":"Numerical study on mechanisms underlying the heat transfer enhancement of upward supercritical CO2 flow at low Reynolds numbers near the pseudo-critical region through a microtube","authors":"Ergin Bayrak ,&nbsp;Hojin Ahn","doi":"10.1016/j.icheatmasstransfer.2025.108995","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108995","url":null,"abstract":"<div><div>The buoyancy and thermal acceleration effects of supercritical CO₂ flow near the pseudo-critical region have been widely mentioned as the mechanism of heat transfer enhancement in the literature. However, most publications deal with turbulent flows and do not discuss the details of how these effects alter flow structure and enhance heat transfer. The present study numerically investigated mechanisms underlying the heat transfer enhancement of upward supercritical CO₂ flow through a microtube, 0.5 mm in diameter, at low Reynolds numbers. The heat transfer enhancement was closely associated with the appearance and disappearance of the M-shaped velocity profile. When the M-shaped profile started forming by the buoyancy effect, the first local maximum of the heat transfer coefficient appeared as the thermal acceleration of the boundary layer entrained fluid from the wall region. The fluid entrainment carried thermal energy from the wall toward the core, thus enhancing the heat transfer. When the M-shaped profile started disappearing due to the thermal acceleration in the core region, the second maximum appeared in some cases due to abrupt turbulence developed by two forces in the opposite direction: one force dragging the local maximum velocity in the M-shaped profile and the other force accelerating the core region.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"165 ","pages":"Article 108995"},"PeriodicalIF":6.4,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143887219","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":"Enhanced heat transfer on hollow hierarchical nanowired surface during transient spray cooling of liquid nitrogen","authors":"Yiming Fan ,&nbsp;Fengmin Su ,&nbsp;Jiahui Peng ,&nbsp;Letian Fan ,&nbsp;Chao Chang ,&nbsp;Yulong Ji ,&nbsp;Rongfu Wen ,&nbsp;Guoliang Zhu","doi":"10.1016/j.icheatmasstransfer.2025.108982","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108982","url":null,"abstract":"<div><div>The liquid spreading and replenishment has a key effect on the performance of transient spray cooling. In this study, we used liquid nitrogen as the working fluid and conducted transient spray cooling experiments on four modified copper surfaces, including superhydrophilic surface, hydrophilic surface, smooth copper surface, and hollow hierarchical nanowired surface. The results show that increasing the single-scale surface hydrophilicity of the copper surface can effectively increase the critical heat flux (CHF) of liquid nitrogen transient spray cooling, due to the effective enhancement of evaporation heat transfer coefficient <em>h</em>. The multi-scale hollow hierarchical structure surface can further enhance the heat transfer of liquid nitrogen transient spray cooling, its cooling rate is accelerated 1.3 times, the CHF is increased 1.2 times and the maximum <em>h</em>_<em>MAX</em> is increased 1.11 times that of the superhydrophilic surface. Through the calculation of the liquid film climb theory model, it was found that the liquid nitrogen film climbs at a speed of 48.10 m/s in the nanowired clusters. The ultrafast climb of liquid nitrogen film in hierarchical nanowires may be one of the main reasons for enhanced heat transfer. This study broadens the experimental database of hierarchical structure surfaces and new ideas on enhanced heat transfer during cryogenic spray cooling.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"165 ","pages":"Article 108982"},"PeriodicalIF":6.4,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143882430","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":"Transpiration cooling performance of carbon fiber oxidation-induced Mullite/Al2O3 porous ceramic composite for hypersonic vehicles","authors":"Andi Lin,&nbsp;Jie Huang,&nbsp;Buyue Zhao,&nbsp;Haiming Huang","doi":"10.1016/j.icheatmasstransfer.2025.108991","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108991","url":null,"abstract":"<div><div>As a candidate for active thermal protection in next-generation hypersonic vehicles, transpiration cooling technology has an excellent capacity to reduce heat. However, it remains constrained by material scarcity with simultaneously adapted permeability and high-temperature endurance. To address this critical bottleneck, we developed an innovative Mullite fiber reinforced Al₂O₃ (Mullite/Al₂O₃) porous ceramic through a carbon fiber oxidation-induced approach combined with grinding-mold pressing-sintering process. The comprehensive properties of the ceramic, such as permeability, pore size distribution, high-temperature resistance, and thermal shock resistance, were systematically investigated. The results showed that the Mullite/Al₂O₃ porous ceramic features low density (1.35 g/cm³), good permeability (1.79 × 10⁻¹³ m²), uniform pore size distributions (3.6–10.3 μm), and excellent temperature resistance (&gt;1500 °C). After 10 thermal shock cycles (1500 °C to 20 °C quenching), the ceramic retained 65.9 % of its initial compressive strength (31.08 MPa) and 52.0 % of its initial flexural strength (13.25 MPa). In addition, oxyacetylene flame tests on nose cones demonstrated remarkable transpiration cooling efficiency under 5.3 MW/m² heat flux. This study demonstrates the effectiveness of the synergistic fabrication strategy integrating carbon fiber oxidation-induced pore generation with mullite fiber reinforced architecture, validating the exceptional performance and thermal protection capacity under extreme aerodynamic heating conditions, providing a viable solution for hypersonic thermal protection systems.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"165 ","pages":"Article 108991"},"PeriodicalIF":6.4,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143882428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of particles deposition on film-cooled leading edge with transverse trenches and convex structures by experimental simulations","authors":"Zhengang Liu ,&nbsp;Yixuan Zhang ,&nbsp;Xinyan Xu ,&nbsp;Long Cheng ,&nbsp;Yaguo Lyu ,&nbsp;Fei Zhang","doi":"10.1016/j.icheatmasstransfer.2025.108986","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108986","url":null,"abstract":"<div><div>The leading edge of turbine vane usually suffers severe particles deposition. An experiment at ambient temperature is designed to simulate particles deposition on film-cooled leading edges with transverse trenches and micro convex structures, aiming to investigate their effects on the deposition and cooling effectiveness on the leading edge. The results show that the trenches could make the deposition distribution more uniform along the row of film cooling holes and the micro convex structures have a little similar effect. As the trench depth increases from 0.0<em>D</em> to 1.0<em>D</em>, the deposition rate is reduced and not changed remarkably by further increasing the depth. The micro convex structures could further reduce the deposition but only remarkably for the models with shallow trenches. As blowing ratio increases, the deposition rate increases and could be reduced by the trenches and micro convex structures. The trenches have better robust for reducing the deposition and could reduce the cooling effectiveness loss due to the deposition. The micro convex structures only could increase slightly the cooling effectiveness near film cooling holes for the reference model. The results may be helpful for designing film cooling configuration on the leading edge of turbine vane to reduce the damage of deposition.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"165 ","pages":"Article 108986"},"PeriodicalIF":6.4,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143882429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The discrete unified gas kinetic scheme with constant Neumann boundary condition for flow and heat transfer","authors":"Yutao Huo ,&nbsp;Xiuli Cheng ,&nbsp;Meng Wang ,&nbsp;Siqi Wang ,&nbsp;Zhonghao Rao","doi":"10.1016/j.icheatmasstransfer.2025.108981","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108981","url":null,"abstract":"<div><div>In this paper, a new Neumann boundary condition is proposed for the discrete unified gas kinetics scheme (DUGKS) in this paper. The boundary has been verified by solving several flow and heat transfer problems, such as heat transfer between two concentric circles, lid-driven in a cavity heated by constant heat flux and Natural convection around a heated circular object. The results showed that the DUGKS with proposed Neumann boundary possesses second-order accuracy by comparing with the analytical solution of the one-dimensional temperature field. Furthermore, the unstructured mesh can be used to obtain the results of velocity and temperature, where the relative errors are both less than 2 %, compared with ANSYS FLUENT using the same mesh system. The results show that Neumann boundary constructed in this paper can accurately solve the flow field and temperature field.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"165 ","pages":"Article 108981"},"PeriodicalIF":6.4,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143878620","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 and numerical study on the burning and opposed flame spread behaviors over PMMA under different flow conditions","authors":"Kun Zhao,&nbsp;Yanming Zhou,&nbsp;Situo Li,&nbsp;Ziming Lin","doi":"10.1016/j.icheatmasstransfer.2025.108989","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108989","url":null,"abstract":"<div><div>Opposed flame spread over PMMA under different flow velocities (<span><math><msub><mi>u</mi><mo>∞</mo></msub></math></span>) and temperatures (<span><math><msub><mi>T</mi><mo>∞</mo></msub></math></span>) was studied experimentally and numerically. By comparing the local flame standoff distance and burning rate from simulations with theoretical derivation, it was found that the normalized flame standoff distance varies inversely with the square root of the local Reynolds number. The valley effect on the local burning rate increases with <span><math><msub><mi>u</mi><mo>∞</mo></msub></math></span> and an effective B-number is about 0.88. Flame spread rate is less sensitive to <span><math><msub><mi>u</mi><mo>∞</mo></msub></math></span> at <span><math><msub><mi>u</mi><mo>∞</mo></msub></math></span>≤1 m/s due to the counteracting effect of flow velocity on the heat feedback to the preheating region through solid and gas phases. At higher flow velocities, the dominance of reduced gas-phase heat feedback leads to a decreased flame spread rate. In addition, an increase in <span><math><msub><mi>T</mi><mo>∞</mo></msub></math></span> increases the thermal penetration depth, resulting in a greater role played by solid-phase heat conduction. As a result, the critical criterion for the thermally-thick decreases at larger flow temperatures. Based on the theoretical analysis, <span><math><msub><mi>L</mi><mi>p</mi></msub></math></span> was found to be proportional to <span><math><msub><mi>V</mi><mi>f</mi></msub></math></span> and sample thickness with an exponent of 0.66, <span><math><msub><mi>L</mi><mi>p</mi></msub></math></span>=10,913 <span><math><msup><mfenced><mfrac><mrow><msup><msub><mi>V</mi><mi>f</mi></msub><mn>2</mn></msup><msup><mi>δ</mi><mn>2</mn></msup></mrow><mrow><msub><mi>u</mi><mo>∞</mo></msub><msub><mi>μ</mi><mo>∞</mo></msub><msub><mi>ρ</mi><mo>∞</mo></msub></mrow></mfrac></mfenced><mn>0.66</mn></msup></math></span>. <span><math><msub><mi>L</mi><mi>f</mi></msub></math></span> is independent of the flow properties and depends on <span><math><msub><mi>L</mi><mi>p</mi></msub></math></span> for laminar flames, <span><math><msub><mi>L</mi><mi>f</mi></msub><mo>=</mo><mn>4.45</mn><msub><mi>L</mi><mi>p</mi></msub></math></span>. For transient or turbulent flames, <span><math><msub><mi>L</mi><mi>f</mi></msub></math></span> shows less dependence on <span><math><msub><mi>L</mi><mi>p</mi></msub></math></span>, <span><math><msub><mi>L</mi><mi>f</mi></msub><mo>=</mo><mn>0.87</mn><msup><msub><mi>L</mi><mi>p</mi></msub><mrow><mn>2</mn><mo>/</mo><mn>3</mn></mrow></msup></math></span>.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"165 ","pages":"Article 108989"},"PeriodicalIF":6.4,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143878622","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":"Harnessing transfer learning for achieving superior thermal-hydraulic performance in heterogeneous pin-fin arrays","authors":"Evan M. Mihalko,&nbsp;Amrita Basak","doi":"10.1016/j.icheatmasstransfer.2025.108968","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108968","url":null,"abstract":"<div><div>In gas turbines, achieving greater fuel efficiency and increased thrust demands higher operating temperatures, which require advanced cooling mechanisms to prevent thermo-mechanical failures. Pin-fin arrays, traditionally designed with uniform circular pin-fins, have played a crucial role in cooling the trailing edge of turbine blades. However, the conventional approach of uniform pin-fin size and spacing fails to fully capitalize on the complex and evolving flow field within the domain, potentially limiting the effectiveness of the cooling system. In this paper, a transfer learning framework, which combines Bayesian optimization with computational fluid dynamics, is used to optimize three complex heterogeneous pin-fin array configurations on a large-scale domain which would otherwise be computationally expensive. This framework leverages a small-scale domain which preserves the flow-thermal behavior, allowing for high-throughput evaluations on a high-dimensional input design space, creating robust surrogate models and enabling efficient optimization. The small-scale optimized design is then transferred to the large-scale domain as a starting point for further optimization, reducing computational costs by up to 60 %. It is found that increasing the heterogeneity of pin-fin arrays leads to increases in heat transfer up to 6.8 % and reductions in pressure drop up to 76.7 % when compared to a traditional circular pin-fin array.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"165 ","pages":"Article 108968"},"PeriodicalIF":6.4,"publicationDate":"2025-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143877533","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":"Investigation of heat generation and flow of viscous electron fluid in rectangular conductors","authors":"Andriy A. Avramenko,&nbsp;Andrii I. Tyrinov,&nbsp;Yulia Y. Kovetska,&nbsp;Andrii S. Kobzar","doi":"10.1016/j.icheatmasstransfer.2025.108988","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108988","url":null,"abstract":"<div><div>The study presents, for the first time, results on the flow of viscous electron liquids in conductors with a rectangular cross-section. Analytical results for the current carrier velocity were obtained using a Series solution (Fourier method). The problem was also solved numerically using the Lattice Boltzmann Method (LBM). Comparison of velocity profiles showed good agreement. A dimensionless criterion for the realization of ballistic and hydrodynamic regimes was obtained. An evaluation of heat release was provided as a function of a dimensionless parameter characterizing the conductor's size, as well as the time and mean free path length. It was shown that in the hydrodynamic regime, a reduction in the number of collisions leads to a decrease in heat release intensity.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"165 ","pages":"Article 108988"},"PeriodicalIF":6.4,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874102","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":"Coupled radiative-electromagnetic-thermal modeling and multi-parameter optimization for enhancing heat transfer uniformity in radio frequency pulsed vacuum drying","authors":"Dengwen Lei ,&nbsp;Chao Xu ,&nbsp;Yanhong Liu ,&nbsp;Yongkang Xie ,&nbsp;Xiaoyu Zhang","doi":"10.1016/j.icheatmasstransfer.2025.108970","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108970","url":null,"abstract":"<div><div>In this study, the effects of tray shape, loading thickness, electrode gap, vacuum level, and vacuum pulsation ratio on the heating performance during radio frequency pulsed vacuum drying (RFPVD) were systematically investigated. First, based on the established RF heating model, the radiative heat transfer equation was coupled to improve the accuracy of heat transfer simulation under vacuum conditions. Simulation results showed that the temperature uniformity index (TUI) in RF heating stage was reduced to 0.13 by suppressing the edge aggregation effect of the electric field with circular tray. Additionally, single-layer stacking and increased loading thickness effectively improved the heating rate; however, the resulting enhancement of edge aggregation resulted in the TUI increased to 0.31. When a loading thickness of 45 mm was applied, adjusting the electrode gap to 95 mm increased the heating rate and avoided the localized overheating during the heating stage. At a defined drying temperature, an appropriate vacuum level modulated the moisture evaporation rate to optimize the temperature distribution. The RFPVD experiments verified that ideal temperature distribution uniformity (TUI &lt; 0.112) and post-drying moisture content consistency (coefficient of variation&lt;5 %) could be obtained using multi-parameter optimization guided by simulation results. This study provides a theoretical basis and process optimization strategy for improving heating uniformity in RFPVD drying of granular materials.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"165 ","pages":"Article 108970"},"PeriodicalIF":6.4,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143877532","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":"Flow field characteristics of lignite explosion and inhibitory effect of inert powder NaCl, K2CO3, and KH2PO4","authors":"Tianqi Liu","doi":"10.1016/j.icheatmasstransfer.2025.108987","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108987","url":null,"abstract":"<div><div>The damage caused by coal dust explosions to safety production and public property is incalculable. To reveal the lignite explosion process and suppression, experimental and simulation studies are conducted. The results indicate that energy is released at an accelerated rate within 0.38 s after explosion, at a slowed rate within 0.38–0.62 s, and rapidly dissipated within 0.62–1 s. The explosion consumed a large amount of volatile from lignite particles, followed by moisture and fixed carbon. The error of the simulated pressure is 2.35 %, which proves the high consistency between the simulation and experimental results. The simulation found that before ignition, the lignite particles are evenly dispersed within 100 ms. After the explosion, the high temperature in the flow field spreads outwards in a circular pattern. The impact airflow is blocked by the inner wall, after the energy release is terminated, a vortex of airflow appears near the explosion source. KH₂PO₄ has a better inhibitory effect on lignite explosion than K₂CO₃, and K₂CO₃ has a better inhibitory effect than NaCl. Due to the interaction between carbonate and phosphate ions, the best inhibitory effect is achieved by mixing K₂CO₃ and KH₂PO₄. The synergistic effect of the two is of great significance for promoting industrial explosion prevention.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"165 ","pages":"Article 108987"},"PeriodicalIF":6.4,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874101","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}