International Journal of Heat and Fluid Flow最新文献_第4页

Numerical investigations of jet A–hexane binary fuel droplet impact on a heated solid surface 射流a -己烷二元燃料液滴撞击加热固体表面的数值研究

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2026-01-07 DOI: 10.1016/j.ijheatfluidflow.2025.110223

Arghya Paul, Kanak Raj, Pratim Kumar

In the present work, the numerical study of Jet A Hexane-based binary fuel droplet impact dynamics on heated solid surfaces was conducted. This study is crucial for practical applications such as fuel injection in combustors and thermal management of engine components. The volume of fluid (VOF) method was used to analyse the impact dynamics, spreading behaviour, vaporisation, and heat transfer of n-hexane and Jet-A blended fuel droplets on heated stainless-steel surfaces. Droplet impact dynamics were investigated for two Weber numbers, i.e., 25 and 50, and surface temperatures ranging from 50 °C to 227 °C to capture transitions from gentle spreading to nucleate boiling and rebound phenomena. This work examines how fuel blending influences inertia, lamella formation, vapour recoil, and film boiling regimes. The results show that higher inertia in blended fuels enhances spreading but also triggers stronger vapour recoil at elevated temperatures, leading to droplet rebound. In contrast, pure hexane transitions to a stable film boiling regime at high surface temperatures, resulting in smoother heat flux decline. New correlations were developed linking Weber number, spreading ratio, and wall heat flux, offering predictive insights for real-world combustion scenarios. These findings advance the understanding of bi-component fuel droplet impacts on heated surfaces and provide a framework for designing efficient spray systems in combustors and thermal management in propulsion and power generation applications.

本文对Jet A型二元燃料液滴在加热固体表面上的碰撞动力学进行了数值研究。该研究对实际应用具有重要意义，如燃烧室燃油喷射和发动机部件的热管理。采用流体体积法（VOF）分析了正己烷和Jet-A混合燃料液滴在加热不锈钢表面上的冲击动力学、扩散行为、汽化和传热。研究了两个韦伯数（25和50）和表面温度（50 ~ 227℃）下液滴撞击动力学，以捕捉从温和扩散到成核沸腾和反弹现象的转变。这项工作考察了燃料混合如何影响惯性、薄片形成、蒸汽反冲和薄膜沸腾制度。结果表明，混合燃料中较大的惯性增强了扩散，但在高温下也引发了更强的蒸气反冲，导致液滴反弹。相比之下，纯己烷在高表面温度下转变为稳定的膜沸腾状态，导致热通量下降更平稳。研究人员开发了韦伯数、扩散比和壁面热流密度之间的新相关性，为实际燃烧场景提供了预测性见解。这些发现促进了对双组分燃料液滴在受热表面上的影响的理解，并为在燃烧器中设计有效的喷雾系统以及在推进和发电应用中的热管理提供了一个框架。

{"title":"Numerical investigations of jet A–hexane binary fuel droplet impact on a heated solid surface","authors":"Arghya Paul, Kanak Raj, Pratim Kumar","doi":"10.1016/j.ijheatfluidflow.2025.110223","DOIUrl":"10.1016/j.ijheatfluidflow.2025.110223","url":null,"abstract":"<div><div>In the present work, the numerical study of Jet A Hexane-based binary fuel droplet impact dynamics on heated solid surfaces was conducted. This study is crucial for practical applications such as fuel injection in combustors and thermal management of engine components. The volume of fluid (VOF) method was used to analyse the impact dynamics, spreading behaviour, vaporisation, and heat transfer of n-hexane and Jet-A blended fuel droplets on heated stainless-steel surfaces. Droplet impact dynamics were investigated for two Weber numbers, i.e., 25 and 50, and surface temperatures ranging from 50 °C to 227 °C to capture transitions from gentle spreading to nucleate boiling and rebound phenomena. This work examines how fuel blending influences inertia, lamella formation, vapour recoil, and film boiling regimes. The results show that higher inertia in blended fuels enhances spreading but also triggers stronger vapour recoil at elevated temperatures, leading to droplet rebound. In contrast, pure hexane transitions to a stable film boiling regime at high surface temperatures, resulting in smoother heat flux decline. New correlations were developed linking Weber number, spreading ratio, and wall heat flux, offering predictive insights for real-world combustion scenarios. These findings advance the understanding of bi-component fuel droplet impacts on heated surfaces and provide a framework for designing efficient spray systems in combustors and thermal management in propulsion and power generation applications.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110223"},"PeriodicalIF":2.6,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhancing mixed convection for effective thermal transport in a multi-lid-driven cavity with a heated obstacle 在有加热障碍物的多盖驱动腔中增强混合对流以实现有效的热传输

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2026-01-07 DOI: 10.1016/j.ijheatfluidflow.2026.110237

V. Navaneethakrishnan , S. Sridhar , Selvan Bellan , M. Muthtamilselvan

This study numerically explores the interaction between multi-lid shear and buoyancy forces in an air-filled square cavity containing a centrally placed heated obstacle of varying aspect ratio. Shear is imposed by driving all four cavity walls, with the vertical boundaries moving upward and the horizontal walls moving to the right, and is characterized by the Reynolds number (

R e

). Thermal forcing is introduced by maintaining the obstacle at a constant higher temperature relative to the cavity walls, quantified by the Grashof number (

G r

). The governing mass, momentum and energy equations, under the Boussinesq approximation, are solved using the finite volume method over a broad range of

R e

and

G r

, with mixed convection regimes defined by

G r / R e^{2} = 1

. Emphasis is placed on the influence of obstacle aspect ratio on the competition between shear-driven circulation, buoyancy-induced plumes, and their combined effects on thermal transport. Results reveal that the relative strength of

R e

and

G r

governs the dominant transport mechanism. For

R e ≪ G r^{1 / 2}

, buoyancy dominates with vertically ascending plumes, whereas higher

R e

produces diagonal circulations that enhance mixing. Thermal transport is strongly regime-dependent because tall obstacles are more effective in buoyancy-favored conditions, while moderately tall and wide obstacles yield higher thermal transport under shear-dominated, high-intensity conditions. The results have potential applications in enhancing convective thermal transport for efficient thermal regulation across industrial, environmental, and energy systems.

本研究用数值方法探讨了在一个充满空气的方形空腔中多盖剪切力和浮力之间的相互作用，该空腔中有一个中央放置的加热的变宽比障碍物。剪切是通过驱动所有四个腔壁来施加的，垂直边界向上移动，水平壁向右移动，其特征是雷诺数（Re）。热强迫是通过保持障碍物相对于腔壁处于恒定的较高温度来引入的，用格拉什夫数（Gr）来量化。在较宽的Re和Gr范围内，采用有限体积法求解了Boussinesq近似下的控制质量、动量和能量方程，其中混合对流区定义为Gr/Re2=1。重点研究了障碍物长径比对剪切驱动环流和浮力诱导羽流之间竞争的影响，以及它们对热输运的综合影响。结果表明，Re和Gr的相对强度决定了主要的输运机制。对于Re≪Gr1/2，浮力主导着垂直上升的羽流，而较高的Re产生对角线循环，增强了混合。热输运强烈依赖于状态，因为高障碍物在浮力有利的条件下更有效，而中等高和宽的障碍物在剪切主导的高强度条件下产生更高的热输运。研究结果在加强对流热传输以实现工业、环境和能源系统的高效热调节方面具有潜在的应用价值。

{"title":"Enhancing mixed convection for effective thermal transport in a multi-lid-driven cavity with a heated obstacle","authors":"V. Navaneethakrishnan , S. Sridhar , Selvan Bellan , M. Muthtamilselvan","doi":"10.1016/j.ijheatfluidflow.2026.110237","DOIUrl":"10.1016/j.ijheatfluidflow.2026.110237","url":null,"abstract":"<div><div>This study numerically explores the interaction between multi-lid shear and buoyancy forces in an air-filled square cavity containing a centrally placed heated obstacle of varying aspect ratio. Shear is imposed by driving all four cavity walls, with the vertical boundaries moving upward and the horizontal walls moving to the right, and is characterized by the Reynolds number (<span><math><mrow><mi>R</mi><mi>e</mi></mrow></math></span>). Thermal forcing is introduced by maintaining the obstacle at a constant higher temperature relative to the cavity walls, quantified by the Grashof number (<span><math><mrow><mi>G</mi><mi>r</mi></mrow></math></span>). The governing mass, momentum and energy equations, under the Boussinesq approximation, are solved using the finite volume method over a broad range of <span><math><mrow><mi>R</mi><mi>e</mi></mrow></math></span> and <span><math><mrow><mi>G</mi><mi>r</mi></mrow></math></span>, with mixed convection regimes defined by <span><math><mrow><mi>G</mi><mi>r</mi><mo>/</mo><mi>R</mi><msup><mrow><mi>e</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>=</mo><mn>1</mn></mrow></math></span>. Emphasis is placed on the influence of obstacle aspect ratio on the competition between shear-driven circulation, buoyancy-induced plumes, and their combined effects on thermal transport. Results reveal that the relative strength of <span><math><mrow><mi>R</mi><mi>e</mi></mrow></math></span> and <span><math><mrow><mi>G</mi><mi>r</mi></mrow></math></span> governs the dominant transport mechanism. For <span><math><mrow><mi>R</mi><mi>e</mi><mo>≪</mo><mi>G</mi><msup><mrow><mi>r</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msup></mrow></math></span>, buoyancy dominates with vertically ascending plumes, whereas higher <span><math><mrow><mi>R</mi><mi>e</mi></mrow></math></span> produces diagonal circulations that enhance mixing. Thermal transport is strongly regime-dependent because tall obstacles are more effective in buoyancy-favored conditions, while moderately tall and wide obstacles yield higher thermal transport under shear-dominated, high-intensity conditions. The results have potential applications in enhancing convective thermal transport for efficient thermal regulation across industrial, environmental, and energy systems.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110237"},"PeriodicalIF":2.6,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multi-scale analysis of solute dispersion in free and forced convection flow between two parallel plates filled with a porous medium 充满多孔介质的平行板间自由和强制对流流动中溶质弥散的多尺度分析

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2026-01-06 DOI: 10.1016/j.ijheatfluidflow.2025.110234

Aruna A, Swarup Barik

This study investigates the transverse concentration distribution of contaminant transport in free and forced convective flow within a parallel plate filled with a porous medium. The solute undergoes irreversible boundary reactions at the plates. Most previous studies explored similar configurations in free and forced convective flows by incorporating magnetic effects. However, our study introduces a porous medium, which more accurately reflects real-world scenarios, such as pores in particles within flowing rivers or other environments. We develop an analytical solution of the dispersion coefficient, mean and transverse concentration using a multi-scale technique. The present study examines the effects of Grashof number (

G

), porous parameter and relative viscosity in the presence of boundary absorptions on the solute dispersion. Higher porous parameter values reduce permeability, limit solute spreading, and maintain a peak in the mean concentration distribution. In porous media, a negative

G

enhances solute dispersion near the upper boundary, whereas a positive

G

influences dispersion when the lower boundary absorbs. The buoyancy forces dominate for

G > 0

or

G < 0

, driving the flow toward the heating or cooling plates and intensifying non-uniformity in the transverse concentration distribution. This effect becomes more significant with higher porosity and viscosity, as the porous medium reduces permeability and increases resistance to fluid motion. When boundary reactions are considered in the presence of a porous medium under free and forced convection, they cause uneven solute distribution as the walls absorb solute. A higher porous parameter increases resistance to fluid flow, which amplifies concentration gradients and enhances non-uniformity.

本文研究了在一个充满多孔介质的平行板中，污染物在自由和强制对流中的横向浓度分布。溶质在板上发生不可逆的边界反应。大多数先前的研究通过结合磁效应探索了自由对流和强制对流中的类似结构。然而，我们的研究引入了一种多孔介质，它更准确地反映了现实世界的情况，例如流动的河流或其他环境中颗粒的孔隙。我们利用多尺度技术建立了色散系数、平均浓度和横向浓度的解析解。本研究考察了边界吸收存在时，格拉什夫数(G)、多孔参数和相对粘度对溶质弥散的影响。较高的孔隙参数值会降低渗透率，限制溶质扩散，并在平均浓度分布中保持峰值。在多孔介质中，负G增强靠近上界的溶质色散，而正G影响靠近下界吸收时的色散。在G>；0或G<；0时，浮力占主导地位，促使气流向加热板或冷却板流动，加剧了横向浓度分布的不均匀性。随着孔隙度和粘度的增加，这种影响变得更加明显，因为多孔介质降低了渗透率，增加了流体运动的阻力。当考虑在自由和强制对流下存在多孔介质时的边界反应时，由于壁面吸收溶质，它们会导致溶质分布不均匀。较高的孔隙参数增加了流体流动阻力，从而放大了浓度梯度，增强了非均匀性。

{"title":"Multi-scale analysis of solute dispersion in free and forced convection flow between two parallel plates filled with a porous medium","authors":"Aruna A, Swarup Barik","doi":"10.1016/j.ijheatfluidflow.2025.110234","DOIUrl":"10.1016/j.ijheatfluidflow.2025.110234","url":null,"abstract":"<div><div>This study investigates the transverse concentration distribution of contaminant transport in free and forced convective flow within a parallel plate filled with a porous medium. The solute undergoes irreversible boundary reactions at the plates. Most previous studies explored similar configurations in free and forced convective flows by incorporating magnetic effects. However, our study introduces a porous medium, which more accurately reflects real-world scenarios, such as pores in particles within flowing rivers or other environments. We develop an analytical solution of the dispersion coefficient, mean and transverse concentration using a multi-scale technique. The present study examines the effects of Grashof number (<span><math><mi>G</mi></math></span>), porous parameter and relative viscosity in the presence of boundary absorptions on the solute dispersion. Higher porous parameter values reduce permeability, limit solute spreading, and maintain a peak in the mean concentration distribution. In porous media, a negative <span><math><mi>G</mi></math></span> enhances solute dispersion near the upper boundary, whereas a positive <span><math><mi>G</mi></math></span> influences dispersion when the lower boundary absorbs. The buoyancy forces dominate for <span><math><mrow><mi>G</mi><mo>></mo><mn>0</mn></mrow></math></span> or <span><math><mrow><mi>G</mi><mo><</mo><mn>0</mn></mrow></math></span>, driving the flow toward the heating or cooling plates and intensifying non-uniformity in the transverse concentration distribution. This effect becomes more significant with higher porosity and viscosity, as the porous medium reduces permeability and increases resistance to fluid motion. When boundary reactions are considered in the presence of a porous medium under free and forced convection, they cause uneven solute distribution as the walls absorb solute. A higher porous parameter increases resistance to fluid flow, which amplifies concentration gradients and enhances non-uniformity.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110234"},"PeriodicalIF":2.6,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Heat transfer characteristics of nonlinearly graded metal foam in thermal storage tank: A novel framework model of BP neural network fused with tactical unit algorithm 储热罐内非线性梯度金属泡沫的传热特性：一种融合战术单元算法的BP神经网络框架模型

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2026-01-06 DOI: 10.1016/j.ijheatfluidflow.2026.110236

Jiayi Gao , Xinyu Gao , Yuanji Li , Xiaohu Yang , Ya-Ling He

Metal foams (MF) are widely used in phase change materials (PCMs) due to their high thermal conductivity, high porosity and large specific surface area. These characteristics jointly improve the thermal performance of PCMs. This study investigates the influence of porosity variation (ranging from 0.85 to 0.96) on the thermal behavior of a phase change thermal storage (PCTS) unit. The research finds that while the reduction of porosity significantly improves the heat storage efficiency, it concurrently reduces the overall storage capacity. Specifically, compared to a porosity of 0.96, a porosity of 0.85 leads to a 71.06% increase in efficiency but is accompanied by a 10.51% decrease in capacity. To further optimize the prediction performance, an improved Tactical Unit Algorithm (ITUA), incorporating elite retention, Lévy flight, and Gaussian mutation strategies, is proposed. Compared to conventional algorithms, ITUA exhibits markedly enhanced optimization performance. Furthermore, ITUA is integrated with a backpropagation artificial neural network (BP-ANN) to develop a model of liquid phase distribution during the melting process. To maintain heat storage capacity while enhancing efficiency, both linear and nonlinear porosity distributions are investigated. At an average porosity of 0.95, energy storage efficiency is increased by 58.46% and 68.95% for linear and nonlinear arrangements, respectively, relative to uniform porosity distribution. The proposed model provides valuable guidance for optimizing MF porosity configuration in PCTS systems.

金属泡沫材料因其高导热性、高孔隙率和大比表面积而被广泛应用于相变材料中。这些特性共同提高了pcm的热性能。本文研究了孔隙度变化（0.85 ~ 0.96）对相变储热（PCTS）装置热行为的影响。研究发现，孔隙率的降低在显著提高储热效率的同时，也降低了整体储热容量。具体来说，与孔隙度为0.96相比，孔隙度为0.85时，效率提高了71.06%，但产能降低了10.51%。为了进一步优化预测性能，提出了一种改进的战术单元算法（ITUA），该算法结合了精英保留、lsamvy飞行和高斯突变策略。与传统算法相比，ITUA的优化性能显著提高。此外，将ITUA与反向传播人工神经网络（BP-ANN）相结合，建立了熔化过程中液相分布的模型。为了在保持储热能力的同时提高储热效率，研究了孔隙率的线性和非线性分布。在平均孔隙度为0.95时，线性排列和非线性排列的储能效率分别比均匀孔隙度分布提高了58.46%和68.95%。所提出的模型为优化PCTS系统中MF孔隙度配置提供了有价值的指导。

{"title":"Heat transfer characteristics of nonlinearly graded metal foam in thermal storage tank: A novel framework model of BP neural network fused with tactical unit algorithm","authors":"Jiayi Gao , Xinyu Gao , Yuanji Li , Xiaohu Yang , Ya-Ling He","doi":"10.1016/j.ijheatfluidflow.2026.110236","DOIUrl":"10.1016/j.ijheatfluidflow.2026.110236","url":null,"abstract":"<div><div>Metal foams (MF) are widely used in phase change materials (PCMs) due to their high thermal conductivity, high porosity and large specific surface area. These characteristics jointly improve the thermal performance of PCMs. This study investigates the influence of porosity variation (ranging from 0.85 to 0.96) on the thermal behavior of a phase change thermal storage (PCTS) unit. The research finds that while the reduction of porosity significantly improves the heat storage efficiency, it concurrently reduces the overall storage capacity. Specifically, compared to a porosity of 0.96, a porosity of 0.85 leads to a 71.06% increase in efficiency but is accompanied by a 10.51% decrease in capacity. To further optimize the prediction performance, an improved Tactical Unit Algorithm (ITUA), incorporating elite retention, Lévy flight, and Gaussian mutation strategies, is proposed. Compared to conventional algorithms, ITUA exhibits markedly enhanced optimization performance. Furthermore, ITUA is integrated with a backpropagation artificial neural network (BP-ANN) to develop a model of liquid phase distribution during the melting process. To maintain heat storage capacity while enhancing efficiency, both linear and nonlinear porosity distributions are investigated. At an average porosity of 0.95, energy storage efficiency is increased by 58.46% and 68.95% for linear and nonlinear arrangements, respectively, relative to uniform porosity distribution. The proposed model provides valuable guidance for optimizing MF porosity configuration in PCTS systems.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110236"},"PeriodicalIF":2.6,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Research progress of film cooling on turbine blades with different profiles 不同叶型涡轮叶片气膜冷却研究进展

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2026-01-06 DOI: 10.1016/j.ijheatfluidflow.2026.110245

Jialin Liu , Guoqing Li , Chenfeng Wang , Xiaohui Bai , Yanfeng Zhang , Xingen Lu

Film cooling is a commonly used method to solve the high turbine inlet temperature for aero-engines. In recent decades, many studies on film cooling have been conducted based on various blade profiles. In order to summarize the film cooling performance of different blade profiles and provide help for subsequent film cooling design, an overview is conducted in this paper that highlights the effects of different blade profiles. Due to variations in secondary flow structures within the blade passages of different profiles, a comparative analysis is provided on the influence of secondary flow on film cooling performance. Through comparing film cooling performance of different profiles, local regions of high heat flux are formed in different parts of the blade surface under the influence of the passage vortex, leakage vortex, and inlet swirl. The size and location of these high heat flux regions are related to the profile geometry. Further research on film cooling could be conducted based on more complex bowed and twist blades, with precise and targeted design for high heat flux areas on the blade surface.

气膜冷却是解决航空发动机进气温度过高的常用方法。近几十年来，人们对不同叶片型线的气膜冷却进行了大量研究。为了总结不同叶型的气膜冷却性能，为后续的气膜冷却设计提供帮助，本文对不同叶型的效果进行了概述。由于不同叶型通道内二次流结构的差异，对比分析了二次流对气膜冷却性能的影响。通过对比不同叶型的气膜冷却性能，在通道涡、泄漏涡和进口涡的影响下，叶片表面不同部位形成了局部高热流密度区域。这些高热流区的大小和位置与剖面几何形状有关。进一步的气膜冷却研究可以基于更复杂的弯曲和扭曲叶片，对叶片表面的高热流密度区域进行精确和有针对性的设计。

{"title":"Research progress of film cooling on turbine blades with different profiles","authors":"Jialin Liu , Guoqing Li , Chenfeng Wang , Xiaohui Bai , Yanfeng Zhang , Xingen Lu","doi":"10.1016/j.ijheatfluidflow.2026.110245","DOIUrl":"10.1016/j.ijheatfluidflow.2026.110245","url":null,"abstract":"<div><div>Film cooling is a commonly used method to solve the high turbine inlet temperature for aero-engines. In recent decades, many studies on film cooling have been conducted based on various blade profiles. In order to summarize the film cooling performance of different blade profiles and provide help for subsequent film cooling design, an overview is conducted in this paper that highlights the effects of different blade profiles. Due to variations in secondary flow structures within the blade passages of different profiles, a comparative analysis is provided on the influence of secondary flow on film cooling performance. Through comparing film cooling performance of different profiles, local regions of high heat flux are formed in different parts of the blade surface under the influence of the passage vortex, leakage vortex, and inlet swirl. The size and location of these high heat flux regions are related to the profile geometry. Further research on film cooling could be conducted based on more complex bowed and twist blades, with precise and targeted design for high heat flux areas on the blade surface.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110245"},"PeriodicalIF":2.6,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cross scale study on the evaporation process of wet metallic wire mesh layer and its heat dissipation performance analysis 湿金属丝网层蒸发过程的交叉尺度研究及其散热性能分析

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2026-01-03 DOI: 10.1016/j.ijheatfluidflow.2025.110232

Zhongtao Bai, Xiaoyu Jia, Haoran Zhao, Jian Yang, Mei Lin, Qiuwang Wang

The surface microstructure of a copper mesh was first etched and modified to fabricate an ultra‑thin, hydrophilic wicking core capable of delivering liquid water while dissipating heat through evaporation. At the interfacial scale, a “stepwise wetting” process was for the first time revealed by high‑speed microscopic observation: liquid bridges were observed to nucleate at warp‑weft intersections and subsequently propagate across the mesh node by node, with the subsequent drying stage likewise dominated by the behavior of liquid bridges. The wetting rate of the mesh was found to accelerate with increasing mesh number, while the evaporation process was observed to intensify at higher mesh counts. At the macroscopic scale, a coupled heat‑and‑mass‑transfer model was established, demonstrating that the unsaturated evaporation process can be clearly divided into an externally controlled constant‑rate period (approximately 500 s) and an internally limited falling‑rate period. Evaporation efficiency was effectively enhanced by adopting a graded structure with finer pores at the bottom and coarser pores at the top, combined with reduced layer thickness. For saturated evaporation, the evaporative heat‑transfer coefficient was maintained stable above 30 W· m⁻²· K⁻¹ and conductive thermal resistance was minimized by keeping the stacked structure in a fully saturated state; under such conditions, the overall heat‑transfer coefficient was primarily governed by airflow conditions and structural thickness. Through interfacial‑scale visualization experiments and macroscopic‑scale numerical modeling, a cross‑scale systematic investigation of the evaporation process in moist wire‑mesh thin layers was achieved. Important guidance for the performance optimization of plate‑type heat sinks in transformers is provided by these findings.

首先蚀刻和修改铜网的表面微观结构，以制造超薄的亲水芯芯，能够输送液态水，同时通过蒸发散热。在界面尺度上，高速显微观察首次揭示了“逐步润湿”过程：观察到液体桥在经纬交叉处成核，随后在网格上一个节点一个节点地传播，随后的干燥阶段同样由液体桥的行为主导。网格的润湿速率随着网格数的增加而加快，而蒸发过程随着网格数的增加而加剧。在宏观尺度上，建立了传热传质耦合模型，表明非饱和蒸发过程可以明确地分为外部控制的恒速率周期（约500 s）和内部限制的降速率周期。采用底部细孔、顶部粗孔的梯度结构，并减小层厚，可有效提高蒸发效率。对于饱和蒸发，通过保持层叠结构处于完全饱和状态，蒸发换热系数稳定在30 W·m−2·K−1以上，传导热阻最小；在这种情况下，总体换热系数主要受气流条件和结构厚度的影响。通过界面尺度的可视化实验和宏观尺度的数值模拟，对湿丝网薄层中的蒸发过程进行了跨尺度的系统研究。这些发现为变压器板式散热器的性能优化提供了重要的指导。

{"title":"Cross scale study on the evaporation process of wet metallic wire mesh layer and its heat dissipation performance analysis","authors":"Zhongtao Bai, Xiaoyu Jia, Haoran Zhao, Jian Yang, Mei Lin, Qiuwang Wang","doi":"10.1016/j.ijheatfluidflow.2025.110232","DOIUrl":"10.1016/j.ijheatfluidflow.2025.110232","url":null,"abstract":"<div><div>The surface microstructure of a copper mesh was first etched and modified to fabricate an ultra‑thin, hydrophilic wicking core capable of delivering liquid water while dissipating heat through evaporation. At the interfacial scale, a “stepwise wetting” process was for the first time revealed by high‑speed microscopic observation: liquid bridges were observed to nucleate at warp‑weft intersections and subsequently propagate across the mesh node by node, with the subsequent drying stage likewise dominated by the behavior of liquid bridges. The wetting rate of the mesh was found to accelerate with increasing mesh number, while the evaporation process was observed to intensify at higher mesh counts. At the macroscopic scale, a coupled heat‑and‑mass‑transfer model was established, demonstrating that the unsaturated evaporation process can be clearly divided into an externally controlled constant‑rate period (approximately 500 s) and an internally limited falling‑rate period. Evaporation efficiency was effectively enhanced by adopting a graded structure with finer pores at the bottom and coarser pores at the top, combined with reduced layer thickness. For saturated evaporation, the evaporative heat‑transfer coefficient was maintained stable above 30 W· m<sup>−2</sup>· K<sup>−1</sup> and conductive thermal resistance was minimized by keeping the stacked structure in a fully saturated state; under such conditions, the overall heat‑transfer coefficient was primarily governed by airflow conditions and structural thickness. Through interfacial‑scale visualization experiments and macroscopic‑scale numerical modeling, a cross‑scale systematic investigation of the evaporation process in moist wire‑mesh thin layers was achieved. Important guidance for the performance optimization of plate‑type heat sinks in transformers is provided by these findings.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"119 ","pages":"Article 110232"},"PeriodicalIF":2.6,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electroosmotic transport and thermal management of hybrid nanofluids in microchannels for transportation cooling systems 输送冷却系统微通道中混合纳米流体的电渗透输送和热管理

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-31 DOI: 10.1016/j.ijheatfluidflow.2025.110229

Haleem Afsar , Jinping Guan , Ali Alshamrani

This study examines the coupled transport and thermal behavior of peristaltic electroosmotic flow in an asymmetric microchannel motivated by the need for precise fluid manipulation in emerging microscale technologies. The model accounts for electrokinetic forces, externally applied electric and magnetic fields, Hall currents, Joule heating and slip boundary effects, while the electrostatic potential is approximated using the Debye–Hückel formulation. The governing nonlinear equations are reduced through the lubrication approximation and solved numerically using a shooting method. The results show that stronger electromagnetic interactions enhance wall heat transfer, whereas higher Hartmann numbers and Helmholtz Smoluchowski velocities suppress velocity profiles and lower pressure gradients. Furthermore, the combined action of electroosmotic forcing and peristaltic pumping offers flexible control over heat and momentum transport. These insights clarify how multiple physical effects shape microscale flow behavior and may inform practical microsystem designs, such as compact thermal management units or controlled transport modules in advanced engineering applications.

这项研究考察了不对称微通道中蠕动电渗透流动的耦合传输和热行为，这是由新兴微尺度技术对精确流体操纵的需求所驱动的。该模型考虑了电动势、外加电场和磁场、霍尔电流、焦耳加热和滑移边界效应，而静电势则使用debye - h ckel公式进行近似。通过润滑近似简化控制非线性方程，并采用射击法进行数值求解。结果表明，较强的电磁相互作用增强了壁面换热，而较高的Hartmann数和Helmholtz Smoluchowski速度抑制了速度分布和较低的压力梯度。此外，电渗透强迫和蠕动泵的联合作用提供了对热量和动量传输的灵活控制。这些见解阐明了多种物理效应如何形成微尺度流动行为，并可能为实际的微系统设计提供信息，例如高级工程应用中的紧凑型热管理单元或受控传输模块。

{"title":"Electroosmotic transport and thermal management of hybrid nanofluids in microchannels for transportation cooling systems","authors":"Haleem Afsar , Jinping Guan , Ali Alshamrani","doi":"10.1016/j.ijheatfluidflow.2025.110229","DOIUrl":"10.1016/j.ijheatfluidflow.2025.110229","url":null,"abstract":"<div><div>This study examines the coupled transport and thermal behavior of peristaltic electroosmotic flow in an asymmetric microchannel motivated by the need for precise fluid manipulation in emerging microscale technologies. The model accounts for electrokinetic forces, externally applied electric and magnetic fields, Hall currents, Joule heating and slip boundary effects, while the electrostatic potential is approximated using the Debye–Hückel formulation. The governing nonlinear equations are reduced through the lubrication approximation and solved numerically using a shooting method. The results show that stronger electromagnetic interactions enhance wall heat transfer, whereas higher Hartmann numbers and Helmholtz Smoluchowski velocities suppress velocity profiles and lower pressure gradients. Furthermore, the combined action of electroosmotic forcing and peristaltic pumping offers flexible control over heat and momentum transport. These insights clarify how multiple physical effects shape microscale flow behavior and may inform practical microsystem designs, such as compact thermal management units or controlled transport modules in advanced engineering applications.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"118 ","pages":"Article 110229"},"PeriodicalIF":2.6,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Theoretical study on leakage characteristics of an oil-injected single screw CO2 compressor 喷油单螺杆CO2压缩机泄漏特性的理论研究

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-31 DOI: 10.1016/j.ijheatfluidflow.2025.110230

Qingchun Zhang , Junling Yang , Yanan Li , Zhentao Zhang , Hualin Yang , Yanchang Song , Yan He

Single Screw CO₂ Compressor (SSCC) is an essential component for utilizing CO₂ as working fluid. The miscibility of lubricating oil and CO₂ makes it more complicated to determine leaks in compressors. To investigate the leakage characteristics of the SSCC, a mathematical model for its operating process is developed. This model integrates an oil and gas two-phase leakage model, which considers the solubility of oil and CO₂. The study examined SSCC leakage and performance across varying clearances, speeds, and suction/discharge pressures. Results show that, under constant operating conditions, only indirect leakage of CO₂ dissolved in the oil occurs at smaller clearances. However, as the clearance increases, direct leakage of CO₂ is observed. An increase in clearance results in greater leakage and a decrease in volume and adiabatic efficiency. In addition, the effect of the fitting clearance on leakage is significantly more pronounced than meshing clearance. At the same speed, an increase in the suction pressure or a decrease in the discharge pressure increases the compressor’s volumetric efficiency. As the suction or discharge pressure increases, the adiabatic efficiency first increases and subsequently decreases. The optimum suction and discharge pressures for achieving maximum adiabatic efficiency at varied rotational speeds differ.

单螺杆CO2压缩机（SSCC）是利用CO2作为工作流体的重要部件。润滑油和二氧化碳的混溶性使得确定压缩机的泄漏变得更加复杂。为了研究SSCC的泄漏特性，建立了SSCC运行过程的数学模型。该模型集成了油气两相泄漏模型，考虑了油和CO2的溶解度。该研究测试了SSCC在不同间隙、速度和吸入/排出压力下的泄漏和性能。结果表明，在一定的运行条件下，在较小的间隙下，溶解在油中的CO2只发生间接泄漏。然而，随着间隙的增加，观察到二氧化碳的直接泄漏。间隙的增加导致更大的泄漏和体积和绝热效率的降低。此外，配合间隙对泄漏的影响明显比啮合间隙更明显。在相同的速度下，增加吸入压力或降低排出压力会增加压缩机的容积效率。随着吸、排气压力的增大，绝热效率先增大后减小。在不同转速下达到最大绝热效率的最佳吸入和排出压力是不同的。

{"title":"Theoretical study on leakage characteristics of an oil-injected single screw CO2 compressor","authors":"Qingchun Zhang , Junling Yang , Yanan Li , Zhentao Zhang , Hualin Yang , Yanchang Song , Yan He","doi":"10.1016/j.ijheatfluidflow.2025.110230","DOIUrl":"10.1016/j.ijheatfluidflow.2025.110230","url":null,"abstract":"<div><div>Single Screw CO<sub>2</sub> Compressor (SSCC) is an essential component for utilizing CO<sub>2</sub> as working fluid. The miscibility of lubricating oil and CO<sub>2</sub> makes it more complicated to determine leaks in compressors. To investigate the leakage characteristics of the SSCC, a mathematical model for its operating process is developed. This model integrates an oil and gas two-phase leakage model, which considers the solubility of oil and CO<sub>2</sub>. The study examined SSCC leakage and performance across varying clearances, speeds, and suction/discharge pressures. Results show that, under constant operating conditions, only indirect leakage of CO<sub>2</sub> dissolved in the oil occurs at smaller clearances. However, as the clearance increases, direct leakage of CO<sub>2</sub> is observed. An increase in clearance results in greater leakage and a decrease in volume and adiabatic efficiency. In addition, the effect of the fitting clearance on leakage is significantly more pronounced than meshing clearance. At the same speed, an increase in the suction pressure or a decrease in the discharge pressure increases the compressor’s volumetric efficiency. As the suction or discharge pressure increases, the adiabatic efficiency first increases and subsequently decreases. The optimum suction and discharge pressures for achieving maximum adiabatic efficiency at varied rotational speeds differ.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"118 ","pages":"Article 110230"},"PeriodicalIF":2.6,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Performance analysis and structural optimization of the microchannel heat sink for high power multi-chip heat dissipation 大功率多芯片散热微通道散热片的性能分析与结构优化

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-31 DOI: 10.1016/j.ijheatfluidflow.2025.110231

Yue Hu , Mingpeng Liu , Qinghua Lv , Yucheng Yao , Hui Lv , Saffa Riffat

As power densities in electronic devices rise significantly, effective thermal dissipation is crucial for high power system safety and performance. This challenge is particularly severe in multi-chip applications, where simultaneous temperature uniformity and efficient heat dissipation are required. To address this, a novel microchannel heat sink featuring three key innovations is proposed: contracted the longitudinal main channel to balance the distribution of coolant within the chip, inclined transversal main channels to optimize inter-chip flow allocation, and temperature adaptive rib arrays with graded density to further improve thermal uniformity. A three dimensional numerical model was developed using ANSYS, with performance evaluated through temperature difference, maximum temperature, and pressure drop metrics. The optimized design demonstrates significant performance improvements, achieving 70.37 % enhancement in temperature uniformity and 41 % reduction in thermal resistance at 0.8 m/s flow velocity compared to the baseline configuration. The proposed microchannel heat sink maintains the maximum temperature below 358.15 K under extreme heat flux conditions of 370 W/cm² while constraining temperature difference within 4 K. These results validate the proposed microchannel heat sink as an effective thermal management solution for high power multi-chip devices, offering simultaneous enhancement of temperature uniformity and heat dissipation capability through its multi-scale structural innovations.

随着电子器件中功率密度的显著提高，有效的散热对大功率系统的安全和性能至关重要。这一挑战在多芯片应用中尤为严峻，因为多芯片需要同时保持温度均匀性和高效散热。为了解决这一问题，本文提出了一种新型微通道散热器，该散热器具有三个关键创新：收缩纵向主通道以平衡冷却剂在芯片内的分布；倾斜横向主通道以优化芯片间的流动分配；梯度密度的温度自适应肋阵列以进一步提高热均匀性。利用ANSYS建立了三维数值模型，并通过温差、最高温度和压降指标对性能进行了评估。与基准配置相比，优化后的设计显著提高了性能，在0.8 m/s流速下，温度均匀性提高了70.37%，热阻降低了41%。在370 W/cm2的极端热通量条件下，微通道散热片的最高温度保持在358.15 K以下，同时将温差限制在4 K以内。这些结果验证了所提出的微通道散热器作为高功率多芯片器件的有效热管理解决方案，通过其多尺度结构创新提供同时增强温度均匀性和散热能力。

{"title":"Performance analysis and structural optimization of the microchannel heat sink for high power multi-chip heat dissipation","authors":"Yue Hu , Mingpeng Liu , Qinghua Lv , Yucheng Yao , Hui Lv , Saffa Riffat","doi":"10.1016/j.ijheatfluidflow.2025.110231","DOIUrl":"10.1016/j.ijheatfluidflow.2025.110231","url":null,"abstract":"<div><div>As power densities in electronic devices rise significantly, effective thermal dissipation is crucial for high power system safety and performance. This challenge is particularly severe in multi-chip applications, where simultaneous temperature uniformity and efficient heat dissipation are required. To address this, a novel microchannel heat sink featuring three key innovations is proposed: contracted the longitudinal main channel to balance the distribution of coolant within the chip, inclined transversal main channels to optimize inter-chip flow allocation, and temperature adaptive rib arrays with graded density to further improve thermal uniformity. A three dimensional numerical model was developed using ANSYS, with performance evaluated through temperature difference, maximum temperature, and pressure drop metrics. The optimized design demonstrates significant performance improvements, achieving 70.37 % enhancement in temperature uniformity and 41 % reduction in thermal resistance at 0.8 m/s flow velocity compared to the baseline configuration. The proposed microchannel heat sink maintains the maximum temperature below 358.15 K under extreme heat flux conditions of 370 W/cm<sup>2</sup> while constraining temperature difference within 4 K. These results validate the proposed microchannel heat sink as an effective thermal management solution for high power multi-chip devices, offering simultaneous enhancement of temperature uniformity and heat dissipation capability through its multi-scale structural innovations.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"118 ","pages":"Article 110231"},"PeriodicalIF":2.6,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental and numerical studies on the characteristics and mechanisms of convective heat transfer in gas–liquid two-phase flows 气液两相流对流换热特性及机理的实验与数值研究

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-31 DOI: 10.1016/j.ijheatfluidflow.2025.110209

Wenchao Lv , Maye Shi , Peihong Chen , Jiayi Dai , Hongbin Chen

The generation of air bubbles during the actual production process often results in complex two-phase gas–liquid flows. However, the mechanisms and characteristics of heat transfer in gas–liquid two-phase flows are not yet fully understood, restricting the heat transfer efficiency in the production process. In this study, the convective heat transfer coefficients in gas–liquid two-phase flows were measured using a two-phase flow experimental apparatus. The results reveal that two-phase gas–liquid flows significantly outperformed single-liquid flows in terms of heat transfer efficiency. Notably, the heat transfer coefficients in the slug flows are higher than those in the bubble flows and the churn flows. The distributions of characteristic parameters in the flow field were investigated using numerical methods. It can be found that the gas bubbles can enhance the turbulence in liquid media, increasing the local temperature gradient and heat flux density, thereby significantly improving the heat transfer efficiency. The flow of Taylor bubbles, which comprises the slug flow, generates greater turbulence in the liquid-phase medium, resulting in improved heat transfer efficiency. The regularities and mechanisms of heat transfer in gas–liquid flows uncovered in this study may provide assistance to improve the heat transfer efficiency for industrial production.

实际生产过程中气泡的产生往往导致复杂的气液两相流动。然而，气液两相流的换热机理和特性尚未完全了解，制约了生产过程的换热效率。本文采用气液两相流实验装置，对气液两相流的对流换热系数进行了测量。结果表明，两相气液流动的换热效率明显优于单液流动。值得注意的是，段塞流的换热系数高于气泡流和搅拌流。用数值方法研究了流场中特征参数的分布。可以发现，气泡可以增强液体介质中的湍流，增加局部温度梯度和热流密度，从而显著提高传热效率。泰勒气泡的流动包括段塞流，在液相介质中产生更大的湍流，从而提高了传热效率。研究揭示了气液流动的传热规律和机理，为提高工业生产的传热效率提供了依据。

{"title":"Experimental and numerical studies on the characteristics and mechanisms of convective heat transfer in gas–liquid two-phase flows","authors":"Wenchao Lv , Maye Shi , Peihong Chen , Jiayi Dai , Hongbin Chen","doi":"10.1016/j.ijheatfluidflow.2025.110209","DOIUrl":"10.1016/j.ijheatfluidflow.2025.110209","url":null,"abstract":"<div><div>The generation of air bubbles during the actual production process often results in complex two-phase gas–liquid flows. However, the mechanisms and characteristics of heat transfer in gas–liquid two-phase flows are not yet fully understood, restricting the heat transfer efficiency in the production process. In this study, the convective heat transfer coefficients in gas–liquid two-phase flows were measured using a two-phase flow experimental apparatus. The results reveal that two-phase gas–liquid flows significantly outperformed single-liquid flows in terms of heat transfer efficiency. Notably, the heat transfer coefficients in the slug flows are higher than those in the bubble flows and the churn flows. The distributions of characteristic parameters in the flow field were investigated using numerical methods. It can be found that the gas bubbles can enhance the turbulence in liquid media, increasing the local temperature gradient and heat flux density, thereby significantly improving the heat transfer efficiency. The flow of Taylor bubbles, which comprises the slug flow, generates greater turbulence in the liquid-phase medium, resulting in improved heat transfer efficiency. The regularities and mechanisms of heat transfer in gas–liquid flows uncovered in this study may provide assistance to improve the heat transfer efficiency for industrial production.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"118 ","pages":"Article 110209"},"PeriodicalIF":2.6,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0