International Communications in Heat and Mass Transfer最新文献

{"title":"Modeling and analysis of effective thermal conductivity during hydrate phase transitions","authors":"Shicai Sun,&nbsp;Linlin Gu,&nbsp;Wanxin Tian,&nbsp;Rundong Zhang,&nbsp;Yanping Zhao,&nbsp;Yonghao Yin,&nbsp;Guanru Gong","doi":"10.1016/j.icheatmasstransfer.2025.108872","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108872","url":null,"abstract":"<div><div>Heat transport and mass transfer happen in the hydrate phase transition, effecting variation of the effective thermal conductivity of the hydrate-water-gas-sediment system. The effective thermal conductivity of methane hydrate and of its sediment system was measured experimentally to propose the additional coefficient formula caused by phase transition. The experimental results show that the effective thermal conductivity of the two systems were 0.2284–2.9900 W·m⁻¹·K⁻¹ and 1.0020–1.5030 W·m⁻¹·K⁻¹, and the additional coefficients were 0.5129–4.8619 and 0.5979–1.2504, respectively. The porous media structure can suppress various disturbances in the system and reduces the additional coefficient. The additional coefficient is generally normal distribution or has a linear relationship with the variational hydrate content in the phase transition stage but shows a strong linear connection with temperature in the non-phase transition stage. Based on the relation of additional coefficient and hydrate content, a correction effective thermal conductivity model is proposed to predict the effective thermal conductivity of hydrate-bearing sediment system during hydrate phase transition. The experimental data consistently fall within the predictive bounds of the model, with optimal predictive accuracy observed when the hydrate content is below 0.6. These research findings not only enrich the thermal physical property database, but also provide support for heat transfer analysis in the formation and exploitation of hydrate resources.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"164 ","pages":"Article 108872"},"PeriodicalIF":6.4,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681413","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":"Effects of spatially and temporally varied heat generation on fusion behaviors of thermoplastic composites under local thermal non-equilibrium conditions","authors":"Yuyuan Yang,&nbsp;Yuhang Yuan,&nbsp;Zhenghua Rao,&nbsp;Tian Zhou","doi":"10.1016/j.icheatmasstransfer.2025.108884","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108884","url":null,"abstract":"<div><div>When thermally processing fiber reinforced thermoplastic (FRTP) composites, external fields are usually applied to generate spatially and temporally varied heat sources within composites, leading to complex local thermal non-equilibrium (LTNE) phenomena. To address this issue, a Lattice Boltzmann model is established to simulate the fusion behavior of FRTP composites at the scale of the representative elementary volume. The results show that LTNE effects on the fusion of FRTP composites are significant, especially when material has the low interfacial heat transfer coefficient. The increases in internal heat source power and matrix fraction can significantly accelerate melting rates, especially when considering LTNE effects. As compared to the situation where all parameters are at their minimum, the height of the melting region can be 15 times higher, and the height-to-width ratio of the melting region usually increases by 2–3 times. When fiber thermal conductivity increases, fusion and LTNE effects first increase and then weaken. When matrix fraction is low, increasing matrix fraction can increase temperature difference; but when it is high, it shows the opposite effect. This study provides a theoretical basis for the selection of thermal processing parameters of FRTP composites.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"164 ","pages":"Article 108884"},"PeriodicalIF":6.4,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681320","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 twisted tape-induced mixed convection for optimized thermofluidic performance in transitional flow regimes","authors":"Suvanjan Bhattacharyya ,&nbsp;Devendra Kumar Vishwakarma ,&nbsp;Manoj K. Soni","doi":"10.1016/j.icheatmasstransfer.2025.108865","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108865","url":null,"abstract":"<div><div>The current study aims to experimentally investigate the thermohydrodynamics coaction in a solar air heater tube equipped with twisted tape turbulators, specifically focusing on laminar and transitional flow regimes. This study uses air with Reynolds numbers (Re_a) from 563 to 10,240. Wall heat flux (q) is uniform on heat exchanger tube. On the tube surface, “2, 3, and 4” kW-m⁻² heat fluxes are used. Twisted tapes with twist ratios (y) “3, 4 and 5” were used as passive heat transfer enhancement devices. The results of heat transfer are presented in terms of Nusselt number (Nu_a) and Colburn j-factor (<em>j</em>) while the pressure drop is presented as friction factor (<em>f</em>). The results revealed changes in the transition boundary. For plain channel being subjected to uniform heat flux of 3 kW-m⁻², the transition begins at Re_a equals to 2595 and ends at Re_a 3833. For twisted tape having twist ratio 3 at 4 kW-m⁻² heat flux, the improvement in the heat transfer was highest. Similar results were obtained for <em>f</em>. Four empirical correlations were developed for predicting the Nusselt number (Nu_a) and friction factor (<em>f</em>), achieving deviations as low as ±0.75 % from experimental data. These correlations provide highly reliable guidance for optimizing heat exchanger design and performance.</div></div><div><h3>Novelty</h3><div>This study explores the underexamined transitional flow regime in a solar air heater tube using twisted tape inserts, providing crucial insights into heat transfer and pressure drop. Unlike most works focusing on liquids, it uses air as the working fluid, relevant for solar and HVAC applications. The research identifies critical Reynolds numbers, achieving optimal heat transfer enhancement at a twist ratio of 3 and a heat flux of 4 kW/m². Novel empirical correlations for Nusselt number and friction factor are developed to guide heat exchanger design. The study also evaluates the economic viability of these enhancements, bridging a key knowledge gap in thermal optimization.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"164 ","pages":"Article 108865"},"PeriodicalIF":6.4,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681414","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 thermal management in a photovoltaic solar system with porous heat storage, parabolic reflector and self-cleaning coating","authors":"M. Sheikholeslami ,&nbsp;M.H. Alturaihi","doi":"10.1016/j.icheatmasstransfer.2025.108847","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108847","url":null,"abstract":"<div><div>This work aims to enhance the performance of concentrated photovoltaic-thermal (CPVT) solar systems by integrating a phase change material (PCM) layer to improve solar energy saving and utilization. A parabolic reflector focuses solar irradiation onto the CPVT system, while the discrete ordinates (DO) method is employed to analyze the heat flux distribution on the panel. To mitigate the negative impact of dust deposition on the glass surface, the nanoparticle-based self-cleaning coating is applied. The PCM layer is further optimized using porous foam to increase thermal storage capacity, and fins are added to improve overall system efficiency. Simulations indicated that neglecting buoyancy force effects is a reasonable assumption. Incorporating porous foam and fins in the storage system significantly enhances electrical performance, resulting in a 2.94 % improvement in electrical efficiency (η_el) at higher flow rates (Q), exceeding the PCM-only configuration by 2.66 %. The highest electrical efficiency achieved is 13.35 % with the PCM-Foam-Fins configuration. Additionally, the liquid fraction (LF) decreases significantly with increasing flow rates, showing reductions of 40.74 % without fins and 35.77 % with fins. Coating the glass cover with SiO₂ nanoparticles improves LF, particularly at lower flow rates.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"164 ","pages":"Article 108847"},"PeriodicalIF":6.4,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681416","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":"Moist air transfer and frost distribution characteristics in low-temperature refrigerator","authors":"Guixiang He ,&nbsp;Guoqiang Liu ,&nbsp;Tianyang Zhao ,&nbsp;Gang Yan ,&nbsp;Huawei Zhang","doi":"10.1016/j.icheatmasstransfer.2025.108875","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108875","url":null,"abstract":"<div><div>The application of low-temperature refrigerators set below −30 °C is increasing. Compared to conventional refrigerators set at 5 °C/−18 °C, these low-temperature units face more severe frost issues within their cabinets, which have received less attention. This study focuses on the frost issue in a low-temperature cabinet at −40 °C. Firstly, tracer gas technology and computational fluid dynamics (CFD) simulation were employed innovatively to obtain the moist air transfer rate. Based on this, the distribution ratio of frost between the cabinet walls and evaporator was analyzed. The results show that the moist air transfer rates entering the cabinet through the gasket, defrosting drainage tube, and door opening-closing process are 35.62 g·h⁻¹, 7.12 g·h⁻¹, and 295.7 g per opening. Among these, 67.5 % of the water vapor condenses into frost on the cabinet walls. This increases the difficulty in opening the door, affecting the user experience. Implementing −30 °C and −18 °C frost transfer modes can reduce the frost ratio on the cabinet walls to 52.7 % and 11.4 %. The average door opening force also decreased from 91.3 N to 70.6 N and 51.1 N. This study first explores laws of the moist air transfer rate and frosting distribution in −40 °C low-temperature refrigerator, establishes theoretical foundations to address the frosting issue within cabinet of such refrigerators.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"164 ","pages":"Article 108875"},"PeriodicalIF":6.4,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681412","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 study on the flow and thermal characteristics of a two-phase closed thermosyphon filled with low surface tension working fluid under various wettability","authors":"Wandong Min,&nbsp;Wei Zhong,&nbsp;Lin Wang,&nbsp;Yanping Yuan,&nbsp;Xiaoling Cao","doi":"10.1016/j.icheatmasstransfer.2025.108848","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108848","url":null,"abstract":"<div><div>Although two-phase closed thermosyphons (TPCTs) with low surface tension fluids are increasingly being applied in various fields, existing studies mainly focus on TPCTs with water as the working fluid under different wettability, and there is a lack of research on the condensation dynamics of low surface tension fluids in TPCTs under varying wettability. This paper addresses this gap by presenting a novel CFD model that integrates a dynamic condensation mass transfer time relaxation parameter into the Lee model and couples it with the contact angle model. The results indicate that the numerical model is more accurate in simulating the formation of a liquid film when the liquid phase is set for the primary phase and the density model of the vapor phase is used as an incompressible ideal gas. When low surface tension working fluids, such as methanol and ethanol, are used in TPCTs, the size of bubbles and boiling intensity in the evaporator are lower compared to when water is used as the working fluid. Surface tension and gravity induce the formation of a fluctuating condensate film on the condenser of a methanol-TPCT. The liquid film in the condenser of the ethanol-TPCT is approximately 1.5 times thicker than that of the methanol-TPCT. As the contact angle increases, the thickness of the liquid film on the wall decreases, leading to the phenomenon of temperature rise on the upper wall of the evaporator. These advancements provide a design tool for next-generation TPCTs in applications like data center cooling and hyperloop systems.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"164 ","pages":"Article 108848"},"PeriodicalIF":6.4,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645005","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":"Dynamics of vapor bubble train in flow boiling heat transfer in microchannels","authors":"Odumuyiwa A. Odumosu ,&nbsp;Tianyou Wang ,&nbsp;Zhizhao Che","doi":"10.1016/j.icheatmasstransfer.2025.108859","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108859","url":null,"abstract":"<div><div>Microchannel flow boiling is a promising technique for micro-device thermal management, and understanding the bubble dynamics in microchannel flow boiling is important for the applications. Previous studies only focused on single, isolated bubbles, but the bubbles in microchannel flow boiling applications often exist as bubble trains, in which the bubbles interact with each other. Here, we investigate numerically vapor bubble trains in microchannel flow boiling by adopting the flow-focusing technique to form monodispersed bubbles in the upstream of the microchannel. With increasing the initial vapor–liquid volume ratio, the bubble frequency increases while the growth rate of the bubbles decreases because of the reduced bubble size. With increasing the heat flux on the wall or reducing the latent heat of the working fluid, the bubble train growth rate increases because of the increased vaporization rate. The vaporization of the fluid in the upstream causes the bubble expansion and accelerates the bubble movement in the downstream. The wall temperature and the Nusselt number fluctuate because of the periodic pass-through of bubbles.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"164 ","pages":"Article 108859"},"PeriodicalIF":6.4,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645006","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 novel hybrid deep learning algorithm for estimating temperature-dependent thermal conductivity in transient heat conduction problems","authors":"Wenkai Qiu,&nbsp;Haolong Chen,&nbsp;Huanlin Zhou","doi":"10.1016/j.icheatmasstransfer.2025.108871","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108871","url":null,"abstract":"<div><div>Thermal conductivity is a fundamental parameter in heat transfer, and effectively identifying the thermal conductivity property of materials is crucial for engineering applications. A novel deep learning framework combining bidirectional long short-term memory (Bi-LSTM) networks and multi-head self-attention (MSA) mechanisms is proposed to estimate temperature-dependent thermal conductivity for transient inverse heat conduction problems. The training data is obtained through finite element method (FEM). The temperature fields are utilized as inputs to train the network, enabling it to predict unknown thermal conductivity. A dynamic learning rate decay adjustment strategy is adopted to improve the performance of the model. In the proposed novel hybrid models, Bi-LSTM captures both forward and backward dependencies in the input data, while MSA enhances the learning ability of the model in complex nonlinear relationships by processing input sequences in parallel with different attention weights. Numerical examples analyze the effects of noise and the proportion of training samples on the prediction results, and the results show that the proposed network is less sensitive to noise. Moreover, comparison with other deep learning models highlights the superiority of the proposed framework. It demonstrates accuracy and effectiveness of the proposed method in identifying temperature-dependent thermal conductivity in 2D and 3D models.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"164 ","pages":"Article 108871"},"PeriodicalIF":6.4,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645003","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 investigations on convective heat transfer characteristics of sCO2 in a 10 mm horizontal pipe","authors":"Ziqi Li ,&nbsp;Yulin Chen ,&nbsp;Yingjuan Shao ,&nbsp;Wenqi Zhong","doi":"10.1016/j.icheatmasstransfer.2025.108800","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108800","url":null,"abstract":"<div><div>This study examines heat transfer characteristics of sCO₂ in horizontal tubes with an inner diameter of 10 mm on a self-built experimental system. The effects of operating parameters on heat transfer were investigated. The results indicate that elevating the mass flow rate significantly improves sCO₂ heat transfer efficiency and mitigates heat transfer deterioration (HTD). Conversely, higher inlet temperatures, pressures, and heat flow densities intensify wall temperatures, exacerbating HTD. Moreover, a novel parameter have been mentioned for sCO₂ in the horizontal tube, as the critical heat-to-mass ratio ((q/G)_max).The overall heat transfer performance of sCO₂ will be optimized when the q/G is adjusted to 0.17. Deviation from this value (0.17) may result in HTD. The mechanism of HTD in the horizontal tube was investigated through analysis of thermophysical properties velocity, distribution and turbulent kinetic energy of sCO₂. Finally, new convective heat transfer correlations were proposed by considering the effect of buoyancy force, with more than 90 % of heat transfer coefficient predictions falling within ±20 % relative error. This model can provide insights for the design and operational safety of heat exchange equipment in Brayton cycle coal-fired power generation systems.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"164 ","pages":"Article 108800"},"PeriodicalIF":6.4,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645004","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 analytical inverse model for predicting the critical thickness of the protective bank inside a cylindrical smelting furnace","authors":"Ahmed El-Hassnaoui,&nbsp;Marcel Lacroix","doi":"10.1016/j.icheatmasstransfer.2025.108874","DOIUrl":"10.1016/j.icheatmasstransfer.2025.108874","url":null,"abstract":"<div><div>A protective bank is essential for ensuring the integrity and the energy efficiency of high temperature electric ilmenite smelting furnaces. If the thickness of the protective bank is insufficient or unstable, the refractory walls are directly exposed to molten materials, extreme thermal loads and chemical interactions, accelerating degradation and increasing heat losses. Conventional inverse models rely on iterative processes with high computational costs, limiting real-time capabilities. To overcome this limitation, an analytical inverse model is developed, enabling real-time assessment of furnace integrity based on sensor measurements.</div><div>In this paper, a direct numerical model is first developed and validated to simulate the thermal behavior of a cylindrical smelting furnace. This 2D axisymmetric model accounts for the presence of two superimposed melted layers, iron and slag, while incorporating phase change and endothermic chemical reactions. Next, a 1D analytical inverse model is introduced to predict the critical thickness of the protective bank. Sensor placement is analyzed, demonstrating that deep insertion into the refractory wall enhances measurement accuracy.</div><div>The proposed inverse model successfully determines the critical bank thickness and is further extended to reconstruct its profile by integrating multiple sensors along the furnace height. To account for 2D heat transfer effects in the iron and slag layers, a model correction is introduced, significantly improving prediction accuracy. The results confirm the effectiveness of the proposed approach. Additionally, a measurement error analysis highlights the model's robustness, reinforcing its potential for real-time monitoring and control of high-temperature smelting furnaces.</div></div>","PeriodicalId":332,"journal":{"name":"International Communications in Heat and Mass Transfer","volume":"164 ","pages":"Article 108874"},"PeriodicalIF":6.4,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681410","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}