International Journal of Multiphase Flow最新文献_第7页

Experimental study on multi-scale characteristics of cavitating flows with holographic imaging measurement 空化流多尺度特征的全息成像实验研究

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2026-02-01 Epub Date: 2025-12-04 DOI: 10.1016/j.ijmultiphaseflow.2025.105569

Beichen Tian, Yuntian Wang, Biao Huang, Chao Liu, Yue Wu

Cavitating flows are characterized by multi-phase and multi-scale features, with evolutionary processes involving coupled interactions between the convection evolution of macroscale vapor structures and the growth and motion of microbubbles. The quantitative information and intrinsic physical mechanism are poorly understood, due to limitations of traditional methods in quantitatively measuring the three-dimensional distribution of microbubbles within cavity structures. In the present work, an experimental study integrating high-speed imaging of macroscale cavity convection evolution and quantitative digital in-line holography (DIH) measurement of microbubbles is conducted to investigate multiscale characteristics of cavitating flows. Results demonstrate that cavitation morphology progresses through inception, sheet, and cloud stages with decreasing cavitation numbers, accompanied by gradual increases in maximum attached cavity length and significant growth in discrete bubble quantities. Mesoscale bubbles are predominantly distributed at vapor-liquid interfaces of macroscale cavities, surrounding shedding cloud cavities, and within wake regions of turbulent cavitating flows. Meanwhile, the Sauter mean diameter of microbubbles progressively decreases along the streamwise direction. As the cavitation number decreases, within the cavity-shedding region, shed cavities gradually manifest as large scale cavities, the time-averaged number density of discrete microbubbles first increases and then paradoxically decreases. In contrast, within the wake flow region, shed cavities undergo complete fragmentation into discrete bubbles, resulting in a persistent increase in detectable mesoscale discrete bubbles with decreasing cavitation number. Across all cavitation regimes and the holographic measurement zone, the number of discrete bubbles initially increased then decreased with increasing bubble diameter, with spectral peaks in bubble size distribution (BSD) at 30-40 μm. Turbulent flow structures significantly affect bubble dynamic evolution. Consequently, dual power-law scaling governs the microbubble size distribution, relative to the Hinze scale at approximately 55–65 μm. Sub-Hinze-scale bubbles follow a − 4/3 scaling exponent, whereas super-Hinze-scale bubbles obey a − 10/3 scaling law.

空化流动具有多阶段、多尺度的特征，其演化过程涉及宏观尺度蒸汽结构的对流演化与微泡的生长和运动之间的耦合相互作用。由于传统方法在定量测量微泡在空腔结构中的三维分布方面的局限性，人们对其定量信息和内在的物理机制知之甚少。为了研究空化流动的多尺度特征，将大尺度空化对流演化的高速成像与微气泡的定量数字直线全息测量相结合进行了实验研究。结果表明，空化形态在初始阶段、片状阶段和云状阶段发展，空化数量逐渐减少，最大附着空腔长度逐渐增加，离散气泡数量显著增加。中尺度气泡主要分布在大尺度空腔的气液界面、脱落云腔周围以及湍流空化流的尾迹区域。同时，微气泡的Sauter平均直径沿流方向逐渐减小。随着空化数的减少，在空穴脱落区域内，空穴逐渐表现为大尺度空腔，离散微泡的时间平均数密度先增大后减小。相比之下，在尾流区域内，脱落腔完全破碎成离散气泡，导致可探测的中尺度离散气泡随着空化次数的减少而持续增加。在所有空化区和全息测量区，随着气泡直径的增加，离散气泡的数量先增加后减少，气泡尺寸分布（BSD）的光谱峰位于30 ~ 40 μm。湍流结构对气泡的动态演化有显著影响。因此，相对于约55 ~ 65 μm的Hinze尺度，双幂律尺度控制了微泡的尺寸分布。次规模气泡遵循−4/3的标度指数，而超大规模气泡遵循−10/3的标度规律。

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引用次数: 0

Collision-induced breakup dynamics of binary equal-sized nanodroplets 二元等尺寸纳米液滴的碰撞诱导破碎动力学

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2026-02-01 Epub Date: 2025-12-24 DOI: 10.1016/j.ijmultiphaseflow.2025.105593

Zongjun Yin, Chengbin Zhang, Yongping Chen

The role of scale effects on binary nanodroplet collision dynamics is profound, as interfacial forces exhibit strong size dependence at the nanoscale. This study employs molecular dynamics simulations to investigate head-on collisions of equal-sized water nanodroplets, focusing on rupture mechanisms and interfacial dynamics at the nanoscale. The effect of disjoining pressure on nanoscale interfacial phenomena is elucidated, demonstrating a marked increase in surface energy density in thin films and nanodroplets. Four distinct outcomes are identified: regular coalescence, coalescence after perforation, limited splattering, and divergent splattering, and a regime map is constructed accordingly. The rupture instability of nanosheets formed during binary nanodroplet collisions is dictated by thermocapillary short-wave instabilities, which govern the selection of the critical wavenumber. These instabilities initiate perforation at the periphery of the spreading meniscus and subsequently propagate inward once a critical nanosheet thickness is reached. However, the relevant scaling arguments regarding the critical nanosheet thickness remain to be satisfactorily determined. Therefore, the critical nanosheet thickness is calculated semi-empirically to scale with the nanoscale critical wavelength, demonstrating that the critical thickness intriguingly becomes an invariant value for the range of Ohnesorge numbers considered. Based on the scaled critical nanosheet thickness for nanodroplet breakup, a theoretical model is developed for collision-induced breakup dynamics of binary equal-sized nanodroplets, explicitly incorporating nanoscale disjoining pressure effects. The proposed model is validated against extensive numerical simulations, and good agreement is achieved, demonstrating its predictive power for nanoscale free-flow dynamics where classical theories fail.

尺度效应对二元纳米液滴碰撞动力学的影响是深远的，因为界面力在纳米尺度上表现出强烈的尺寸依赖性。本研究采用分子动力学模拟来研究等大小的纳米水滴的正面碰撞，重点研究纳米尺度上的破裂机制和界面动力学。研究了分离压力对纳米级界面现象的影响，表明薄膜和纳米液滴的表面能密度显著增加。确定了四种不同的结果：规则聚结、穿孔后聚结、有限飞溅和发散飞溅，并据此构建了一个制度图。热毛细短波的不稳定性决定了二元纳米液滴碰撞形成的纳米片的破裂不稳定性，而热毛细短波的不稳定性决定了临界波数的选择。这些不稳定性在扩展的半月板外围引发穿孔，并随后向内传播，一旦达到临界纳米片厚度。然而，关于临界纳米片厚度的相关缩放参数仍有待确定。因此，临界纳米片厚度的计算是半经验的，与纳米尺度临界波长成比例，表明临界厚度在考虑的欧内格数范围内成为一个不变值。基于纳米液滴破碎的临界纳米片厚度，建立了二元等尺寸纳米液滴碰撞诱导破碎动力学的理论模型，明确地考虑了纳米尺度的分离压力效应。通过大量的数值模拟验证了该模型的有效性，并取得了良好的一致性，证明了该模型对纳米尺度自由流动动力学的预测能力。

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引用次数: 0

Impact boiling in real liquids under intense heating rates 在高加热速率下，真实液体的冲击沸腾

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2026-02-01 Epub Date: 2025-12-16 DOI: 10.1016/j.ijmultiphaseflow.2025.105581

H.D. Haustein , E. Elias

This study examines the phenomenon of impact boiling in a uniformly heated liquid containing nucleation sites. This extreme phenomenon may occur in applications with intense heating, as is encountered in lasers and nuclear reactors. Present theoretical analysis couples the energy equation with a non-equilibrium vapor formation model, to describe the crucial competition between rapid volumetric heating and thermal relaxation by latent heat absorption. The pre-existence of nucleation sites limits the heat-up rates to 10⁶ [K/s], and to the thermal bubble growth regime. This balance then yields a criterion for maximum achievable liquid superheat, expressed as a function of the ratio of heating rate to the density of existing vapor embryos. Exceeding this threshold triggers unwanted explosive boiling, characterized by intense vapor generation driven by homogeneous nucleation. The model’s dimensionless formulation allows for generalization to other liquids, beyond water and methanol examined here.

本研究考察了在含有成核点的均匀加热液体中的冲击沸腾现象。这种极端现象可能发生在强加热的应用中，如在激光和核反应堆中遇到的情况。目前的理论分析将能量方程与非平衡蒸汽形成模型相结合，以描述快速体积加热和潜热吸收热松弛之间的关键竞争。成核位置的预先存在限制了升温速率为106 [K/s]，并限制了热泡生长状态。这个平衡然后产生了最大可达到的液体过热的标准，表示为加热速率与现有蒸汽胚密度之比的函数。超过这个阈值会引发不必要的爆炸性沸腾，其特征是由均匀成核驱动的强烈蒸汽产生。该模型的无量纲公式允许推广到其他液体，除了这里检查的水和甲醇。

引用次数: 0

Numerical study of particle rolling entrainment in wall turbulence on rough bed 粗糙床壁面湍流中颗粒滚动夹带的数值研究

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2026-02-01 Epub Date: 2025-11-17 DOI: 10.1016/j.ijmultiphaseflow.2025.105548

Yicong Zhu, Yan Zhang, Ping Wang

The transport of sediment particles in turbulent flow is widespread in nature. The entrainment of bed particle represents the first step in forming and developing multiphase flow. According to the observed fact that the duration of fluid force acting on the particles is equally significant as its magnitude, event-based entrainment criterions have been developed to analyze the dynamical interactions between the particles and turbulence. However, these models, mainly based on wind tunnel or water channel experiments, only focus on the fluid forces and particle motions in two-dimensional plane (streamwise and vertical). Recent studies highlight the importance of spanwise fluid action, which depends on particle bed arrangement. In this work, the semi-resolved particle Lagrangian tracking method and direct numerical simulation of wall turbulence four-way coupled with particles are employed to simulate the rolling entrainment of individual particles for different bed arrangement and various Shields numbers. The simulation results illustrate that on specific bed arrangement, the spanwise fluid effect cannot be neglected and will lead to none-streamwise rolling entrainment. The fluid structures surrounding the particles during the entrainment process were analyzed, revealing that at lower Shields numbers, sweep events are the primary driving force for particle entrainment. Furthermore, for particles initiating motion in the spanwise direction, the conditional surrounding spanwise velocity field is asymmetrical and the spanwise structures are according the direction of motion. After simplifying the complex three-dimensional force/torque analysis by a projection method, a three-dimensional impulse criterion for particle entrainment was developed and validated by the numerical simulation results.

湍流中泥沙颗粒的输运在自然界中是普遍存在的。床层颗粒的夹带是多相流形成和发展的第一步。根据观察到的作用在粒子上的流体力的持续时间与其大小同等重要的事实，建立了基于事件的夹带准则来分析粒子与湍流之间的动力学相互作用。然而，这些模型主要基于风洞或水道实验，只关注二维平面（流向和垂直）的流体力和粒子运动。最近的研究强调了横向流体作用的重要性，这取决于颗粒床的排列。本文采用半分辨粒子拉格朗日跟踪法和粒子耦合壁面湍流四向直接数值模拟，模拟了不同床层布置和不同屏蔽数下单个粒子的滚动夹带。模拟结果表明，在特定的床层布置下，展向流体效应不可忽视，将导致非流向滚动夹带。分析了颗粒在夹带过程中周围的流体结构，揭示了在较低的屏蔽数下，扫描事件是颗粒夹带的主要驱动力。此外，对于沿展向运动的粒子，条件环绕的展向速度场是不对称的，展向结构是符合运动方向的。采用投影法简化了复杂的三维力/力矩分析，建立了粒子夹带的三维冲量判据，并通过数值模拟结果进行了验证。

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引用次数: 0

Segmenting the complex and irregular in two-phase flows: A real-world empirical Study with SAM2 两相流中复杂和不规则的分割：基于SAM2的现实世界实证研究

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2026-02-01 Epub Date: 2025-11-25 DOI: 10.1016/j.ijmultiphaseflow.2025.105557

Semanur Küçük, Cosimo Della Santina, Angeliki Laskari

Segmenting gas bubbles in multiphase flows is a critical yet unsolved challenge in numerous industrial settings, from metallurgical processing to maritime drag reduction. Traditional approaches — and most recent learning-based methods — assume near-spherical shapes, limiting their effectiveness in regimes where bubbles undergo deformation, coalescence, or breakup. This complexity is particularly evident in air lubrication systems, where coalesced bubbles form amorphous and topologically diverse patches. In this work, we revisit the problem through the lens of modern vision foundation models. We cast the task as a transfer learning problem and demonstrate, for the first time, that a fine-tuned Segment Anything Model (SAM v2.1) can accurately segment highly non-convex, irregular bubble structures using as few as 100 annotated images.

在许多工业环境中，从冶金加工到海上减阻，多相流中的气泡分割是一个关键但尚未解决的挑战。传统的方法——以及最近的基于学习的方法——假设接近球形，限制了它们在气泡变形、合并或破裂的情况下的有效性。这种复杂性在空气润滑系统中尤为明显，在空气润滑系统中，气泡会形成无定形的、拓扑结构多样的斑块。在这项工作中，我们通过现代视觉基础模型的镜头重新审视这个问题。我们将该任务作为一个迁移学习问题，并首次证明了微调的分割任意模型（SAM v2.1）可以使用少至100个注释图像准确分割高度非凸、不规则的气泡结构。

引用次数: 0

Data-Free physics-informed neural networks for modeling compressible multiphase flows 模拟可压缩多相流的无数据物理信息神经网络

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2026-02-01 Epub Date: 2025-12-22 DOI: 10.1016/j.ijmultiphaseflow.2025.105589

Rui Liu , Zitong Zhao , Jili Rong

Physics-informed neural networks (PINNs), which formulate loss functions based on the residuals of governing equations, have gained increasing attention for modeling fluid mechanics. However, in compressible flows, the differential form of hyperbolic conservation laws breaks down near discontinuities due to the absence of derivatives. This limitation presents a significant challenge for data-free PINN frameworks. The challenge is further intensified in multiphase flows, where contact discontinuities exhibit more complex structures and interactions, and relevant studies remain limited. To address these challenges, this study proposes a multiphase PINN model incorporating an encoder-decoder convolutional long short-term memory (ConvLSTM) deep learning framework to enable deep feature extraction and global residual computation. A multiphase Godunov-type finite volume method (FVM) loss function is developed based on a highly robust five-equation model. By employing a Godunov-type discretization derived from the weak form of the conservation laws, the framework circumvents the limits associated with strong-form discontinuities. This approach ensures entropy consistency while achieving high-resolution shock capturing in discontinuous regions. Due to the inherent dissipation of the modeling approach, the interface thickness tends to increase over time during flow evolution, which degrades the prediction accuracy of the model. To address this limitation, an improved loss function with interface anti-diffusion properties is proposed to effectively suppress interface smearing and enhance prediction fidelity. Through training and extrapolative prediction on various one-dimensional Riemann problems and high-dimensional shock cases, the proposed multiphase PINN model demonstrates accurate interface tracking and high precision in discontinuous regions. The multiphase PINN model developed in this study offers a novel predictive framework for a broad range of compressible multiphase flow problems.

基于物理信息的神经网络（pinn）基于控制方程的残差制定损失函数，在模拟流体力学方面受到越来越多的关注。然而，在可压缩流动中，由于缺乏导数，双曲守恒定律的微分形式在不连续点附近失效。这一限制对无数据PINN框架提出了重大挑战。在多相流中，接触不连续面表现出更复杂的结构和相互作用，这一挑战进一步加剧，相关研究仍然有限。为了解决这些挑战，本研究提出了一个包含编码器-解码器卷积长短期记忆（ConvLSTM）深度学习框架的多相PINN模型，以实现深度特征提取和全局残差计算。基于高鲁棒五方程模型，建立了多相godunov型有限体积法（FVM）损失函数。通过采用由守恒律的弱形式导出的godunov型离散化，该框架绕过了与强形式不连续相关联的限制。这种方法确保了熵的一致性，同时实现了在不连续区域的高分辨率冲击捕获。由于建模方法固有的耗散，在流动演化过程中界面厚度随时间的增加而增加，从而降低了模型的预测精度。为了解决这一问题，提出了一种具有界面抗扩散特性的改进损失函数，以有效抑制界面涂抹，提高预测保真度。通过对各种一维黎曼问题和高维激波情况的训练和外推预测，所提出的多相PINN模型在不连续区域具有准确的界面跟踪和较高的精度。本研究建立的多相PINN模型为广泛的可压缩多相流问题提供了一个新的预测框架。

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引用次数: 0

Hybrid Eulerian–Lagrangian approach for direct numerical simulations of elastic turbulence 弹性湍流直接数值模拟的欧拉-拉格朗日混合方法

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2026-02-01 Epub Date: 2025-12-22 DOI: 10.1016/j.ijmultiphaseflow.2025.105587

F. Serafini

Direct Numerical Simulation (DNS) is a fundamental tool for studying elastic turbulence (ET), as the polymer stresses that trigger ET are not directly accessible experimentally. We discuss a hybrid Eulerian–Lagrangian approach for DNS, and we show that the main ET features can be consistently observed in a wide range of concentrations and Weissenberg numbers. The hybrid approach does not require a larger resolution compared to fully Eulerian simulations, with the advantage of more accurate predictions of the polymer stress, and a clear link between model parameters and real polymer properties. Furthermore, a Lagrangian description of the polymer phase allows to explore the limiting, but realistic, conditions of small concentration and large Weissenberg number.

直接数值模拟（DNS）是研究弹性湍流（ET）的基本工具，因为触发ET的聚合物应力无法通过实验直接获得。我们讨论了一种用于DNS的欧拉-拉格朗日混合方法，并且我们表明，在广泛的浓度和Weissenberg数范围内，可以一致地观察到主要的ET特征。与全欧拉模拟相比，混合方法不需要更大的分辨率，其优点是更准确地预测聚合物应力，并且模型参数与实际聚合物性质之间有明确的联系。此外，拉格朗日描述的聚合物相允许探索限制，但现实的条件下，小浓度和大的Weissenberg数。

引用次数: 0

Free-spray characteristics and spray-wall interactions of methanol on a gasoline direct injector under flash-boiling and non-flash-boiling conditions 快沸和非快沸条件下甲醇在汽油直喷器上的自由喷雾特性及喷壁相互作用

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2026-02-01 Epub Date: 2025-12-04 DOI: 10.1016/j.ijmultiphaseflow.2025.105562

Hao-Pin Lien , Rafael Clemente-Mallada , Meghna Dhanji , Roberto Torelli , Lyle M. Pickett

Methanol is considered a promising alternative fuel for internal combustion engines (ICEs) due to its high-octane number, fast laminar flame speed, and elevated latent heat of vaporization, all of which support higher compression ratios and improved thermal efficiency. However, its substantial latent heat of vaporization also poses cold-start challenges, such as misfire and fuel film deposition. This study aims to investigate methanol spray morphology and spray-wall interaction using the Spray M injector from the Engine Combustion Network within a constant-pressure flow vessel. A recently developed unified numerical framework capable of modeling both flash and non-flash boiling sprays is validated against experimental liquid volume fraction data acquired via 3-D computed tomography. The results reveal that flash boiling significantly alters the spray morphology, leading to smaller droplets and spray collapse due to enhanced air-entrainment-induced turbulence. Quantitative agreement between experiments and simulations confirms this behavior. Coupled 0-D equilibrium and 3-D computational fluid dynamics analyses show that flash boiling accelerates evaporation and reduces fuel residence time, while non-flash conditions maintain a persistent liquid core more susceptible to wall wetting. Wall temperature diagnostics reveal that spray collapse alters heat transfer patterns by shifting cooling effects. Mixture fraction analysis indicates that evaporation is primarily governed by shear-layer turbulence, though deviations from adiabatic equilibrium mixing emerge under low-turbulence conditions. Finally, increasing fuel, ambient, and wall temperatures reduces wall wetting and film thickness, mitigating cold-start risks. These findings enhance the understanding of methanol sprays’ behavior and support its adoption as a viable, alternative fuel for ICEs.

甲醇被认为是一种很有前途的内燃机替代燃料，因为它的辛烷值高，层流火焰速度快，汽化潜热高，所有这些都支持更高的压缩比和提高的热效率。然而，其巨大的汽化潜热也带来了冷启动的挑战，如失火和燃料膜沉积。本研究旨在利用恒压流容器内发动机燃烧网络的spray M喷油器，研究甲醇喷雾形态和喷雾壁的相互作用。最近开发了一个统一的数值框架，能够模拟闪蒸和非闪蒸沸腾喷雾，并通过三维计算机断层扫描获得实验液体体积分数数据进行验证。结果表明，闪速沸腾显著改变了喷雾的形态，导致液滴变小，并且由于气流引起的湍流增强而导致喷雾崩溃。实验和模拟之间的定量一致证实了这一行为。耦合0-D平衡和3-D计算流体动力学分析表明，闪蒸加速了蒸发，缩短了燃料停留时间，而非闪蒸条件保持了持久的液心，更容易受到壁润湿的影响。壁面温度诊断显示，通过改变冷却效果，喷雾崩塌改变了传热模式。混合分数分析表明，蒸发主要受剪切层湍流控制，尽管在低湍流条件下会出现对绝热平衡混合的偏离。最后，增加燃料、环境温度和管壁温度可以减少管壁湿润和膜厚度，从而降低冷启动风险。这些发现增强了对甲醇喷雾行为的理解，并支持将其作为内燃机可行的替代燃料。

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引用次数: 0

Numerical study of spray cooling: The effect of nozzle arrangement on heat transfer performance 喷雾冷却的数值研究：喷嘴布置对传热性能的影响

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2026-02-01 Epub Date: 2025-11-24 DOI: 10.1016/j.ijmultiphaseflow.2025.105561

Qingshan Chen , Qinrui Zhang , Cong Wang , Kailun Guo , Mingjun Wang , Xiaoyan Wang , Wenxi Tian , Suizheng Qiu , Guanghui Su

Spray cooling technology, known for its high heat transfer efficiency, is widely applied in high heat flux scenarios. However, existing studies often lack efficient model transition strategies for simulating droplet impingement, liquid film formation, and evaporative heat and mass transfer processes, resulting in high computational costs and limited applicability to large-scale fields. This study proposes an innovative numerical spray cooling method called DPM-VOF-LEE. It integrates Volume of Fluid (VOF) and Discrete Phase Model (DPM) with an evaporative heat transfer model through a transition strategy. The DPM model is employed for efficient droplet tracking in the far-field region. In contrast, the VOF model is applied near the wall to resolve liquid film morphology and heat transfer accurately. This model transition method significantly reduces mesh requirements and improves scalability. It is especially suitable for large-area or multi-nozzle spray cooling systems. Results indicate that vertical single-nozzle spraying exhibits the best cooling performance. In dual-nozzle configurations, interference regions enhance heat transfer. Cooling efficiency increases by more than 78 % compared with non-interference cases. For triple-nozzle configurations, the staggered layout achieves faster average temperature reduction on aluminum plates, with cooling efficiency 8.32 % higher than the inline layout.

喷雾冷却技术以其高传热效率而闻名，广泛应用于高热流密度的场合。然而，现有研究往往缺乏有效的模型转换策略来模拟液滴撞击、液膜形成和蒸发传热传质过程，导致计算成本高，对大尺度领域的适用性有限。本研究提出一种创新的数值喷雾冷却方法DPM-VOF-LEE。它通过转换策略将流体体积（VOF）和离散相模型（DPM）与蒸发传热模型相结合。采用DPM模型对液滴进行远场跟踪。而在壁面附近采用VOF模型可以准确地解析液膜形态和传热。这种模型转换方法显著降低了网格需求，提高了可扩展性。特别适用于大面积或多喷嘴喷雾冷却系统。结果表明，垂直单喷嘴喷射冷却效果最好。在双喷嘴结构中，干涉区增强了传热。与无干扰情况相比，冷却效率提高了78%以上。对于三喷嘴配置，交错布局可以更快地降低铝板的平均温度，冷却效率比直线布局高8.32%。

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引用次数: 0

Experimental study of pressure effect on the evolution of slug/pseudo slug flow characteristics in a large diameter slightly upward inclined pipe 压力对大直径微上斜管内段塞/伪段塞流动特性演化的影响实验研究

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2026-02-01 Epub Date: 2025-12-18 DOI: 10.1016/j.ijmultiphaseflow.2025.105583

Ahmed A. Aql , G. Soto-Cortes , E. Al-Safran , E. Pereyra , C. Sarica

This study experimentally investigates the effect of pressure on slug evolution along an 85 m long, 0.156 m ID, and +2° inclined pipe, operated at pressures under 200 and 400 psi, using advanced tracking sensors and topology instruments. The results show that slugs form earlier at lower pressures of 200 psi and undergo more pronounced growth and dissipation cycles, attributed to greater gas compressibility caused by the lower gas-to-liquid density ratio. Additionally, at a pressure of 200 psi, slugs grow more rapidly along the pipe compared to 400 psi. In contrast, results reveal that at higher pressure conditions of 400 psi, the transition from pseudo slug to fully developed slug is delayed due to wave crest breakage. Additionally, mean slug and film lengths grow with distance but exhibit cyclic fluctuations. At the low pressure, these lengths are relatively greater. Additionally, slug frequency decreases more rapidly with distance at low pressure than at high pressure, reflecting a higher rate of slug and wave coalescence.

本研究利用先进的跟踪传感器和拓扑仪器，实验研究了压力对85 m长、0.156 m内径、+2°倾斜管段塞演化的影响，该管段在200和400 psi压力下作业。结果表明，在较低的200 psi压力下，段塞形成得更早，并且经历了更明显的生长和耗散循环，这是由于较低的气液密度比导致了更高的气体压缩性。此外，与400psi压力相比，在200psi压力下，段塞沿着管道生长得更快。相反，结果表明，在400psi的高压条件下，由于波峰破碎，从伪段塞流到完全发育的段塞流的过渡被延迟。此外，平均段塞和膜的长度随距离增长，但表现出周期性波动。在低压下，这些长度相对较大。此外，在低压条件下，段塞流频率随距离的下降速度比高压条件下更快，这反映出段塞流与波的结合速度更快。

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引用次数: 0