International Journal of Multiphase Flow最新文献_第4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 : 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

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 : 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

Direct numerical simulation of a rising CO2 bubble dissolving in quiescent water at high Schmidt number 高施密特数下静水中上升CO2气泡溶解的直接数值模拟

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2025-12-03 DOI: 10.1016/j.ijmultiphaseflow.2025.105566

Yating Wang , Yohei Sato

Three-dimensional direct numerical simulation (DNS) was performed to investigate mass transfer at high Schmidt numbers, focusing on a rising, dissolving gas bubble in a liquid. The objectives are (i) to develop a numerical method based on the volume-of-fluid (VOF) approach for simulating a dissolving gas bubble and (ii) to determine the mesh resolution required to accurately capture the underlying physical phenomena. A sharp-interface phase-change model is employed, in which the species concentration gradient at the gas–liquid interface is calculated using an irregular stencil that accounts for the local interface geometry. The method was first validated against benchmark cases at low Schmidt numbers, and then applied to a 9 mm CO₂ bubble rising in quiescent water. The simulation was performed on grids ranging from 128³ to 2048³, with the finest case using 8192 cores over 15 days. The total simulated physical time was 1.2 s, including the grid-refinement stages up to the finest resolution. The grid-dependence study indicates that the evaluated grid resolutions remain outside the fully asymptotic regime; nevertheless, the 2048³ grid result underestimates the Sherwood number by only about 7 % relative to the empirical correlation. The CO₂ concentration isosurface from the 2048³ case reveals a complex wake structure with elongated filaments and rolled-up sheets, indicative of shear-induced vortices and strong entrainment. The grid-dependence study suggests that even finer grids (e.g., 4096³) may be necessary, highlighting the need for future exascale computing to fully resolve mass transfer at a high Schmidt number (∼530).

采用三维直接数值模拟（DNS）研究了高施密特数下的传质，重点研究了液体中一个上升的、溶解的气泡。目标是：(i)开发一种基于流体体积（VOF）方法的数值方法，用于模拟溶解的气泡；（ii）确定准确捕捉潜在物理现象所需的网格分辨率。采用锐界面相变模型，利用考虑局部界面几何形状的不规则模板计算气液界面处的物质浓度梯度。该方法首先在低施密特数的基准情况下进行了验证，然后应用于静水中上升的9毫米二氧化碳气泡。模拟在128³到2048³的网格上进行，最好的情况是在15天内使用了8192个内核。总模拟物理时间为1.2秒，包括网格细化阶段，直至最佳分辨率。网格依赖性研究表明，计算得到的网格分辨率仍然在完全渐近范围之外；然而，相对于经验相关性，2048³网格结果仅低估了约7%的舍伍德数。2048³的CO₂浓度等面显示了一个复杂的尾迹结构，具有细长的细丝和卷起的薄片，表明剪切诱导的涡和强夹带。网格依赖性研究表明，甚至更细的网格（例如4096³）可能是必要的，强调未来的百亿亿次计算需要在高施密特数（~ 530）下完全解决质量传递问题。

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引用次数: 0

Impact of variability in inlet operating conditions on CO2 transport in pipelines 进口操作条件变化对管道中CO2输送的影响

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2025-11-28 DOI: 10.1016/j.ijmultiphaseflow.2025.105556

Davide Picchi , Valentina Ciriello

The success of CCS technologies relies on the effectiveness and safety of the infrastructure for the transport of carbon dioxide in pressurized pipelines. Unlike natural gas networks, long-distance carbon dioxide transport presents critical design challenges, such as the need for repressurization to prevent two-phase flow conditions and potential freezing. To address this, we propose a comprehensive assessment framework that combines high-fidelity numerical simulations with a stochastic approach based on the Polynomial Chaos Expansion (PCE). Specifically, we employ the Homogeneous Equilibrium Model (HEM) to compute key quantities of interest (QoIs) — related to pressure drop and the maximum distance before repressurization is required — under a design scenario inspired by the Cortez pipeline (Colorado, USA). Based on PCE surrogates, we then perform global sensitivity analyses and uncertainty quantification to evaluate how variability in inlet parameters influences these QoIs, mapping results across a range of realistic operating conditions. Our results provide critical insight into the risks connected with CO₂ transport and support the optimal design of operating conditions. Moreover, the proposed methodology is general and easily applicable to other CO₂ transport facilities.

CCS技术的成功依赖于加压管道中二氧化碳运输基础设施的有效性和安全性。与天然气管网不同，长距离二氧化碳输送在设计上面临着严峻的挑战，例如需要再增压以防止两相流状况和潜在的冻结。为了解决这个问题，我们提出了一个综合评估框架，该框架结合了高保真数值模拟和基于多项式混沌展开（PCE）的随机方法。具体来说，我们采用均匀平衡模型（HEM）来计算关键感兴趣量（QoIs）——与压降和需要再加压前的最大距离相关——设计方案灵感来自Cortez管道（美国科罗拉多州）。基于PCE替代品，我们进行了全局敏感性分析和不确定性量化，以评估进气道参数的可变性如何影响这些质量指标，并在一系列实际操作条件下绘制结果。我们的研究结果为与二氧化碳运输相关的风险提供了关键的见解，并为操作条件的优化设计提供了支持。此外，建议的方法是通用的，很容易适用于其他二氧化碳运输设施。

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引用次数: 0

A weakly-compressible DEM–CFD framework for dense gas–solid multiphase flows: Foundations consistent with reactive coupling 致密气固多相流弱可压缩DEM-CFD框架：符合反应耦合的基础

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2025-11-27 DOI: 10.1016/j.ijmultiphaseflow.2025.105558

Yuki Yakata , Kimiaki Washino , Masaya Muto , Ryoichi Kurose , Takuya Tsuji

The design of large-scale multiphase reactors, such as fluidized beds for methanation, requires numerical methods that are both computationally efficient and physically accurate. This study addresses the limitations of existing approaches, where traditional DEM–CFD solvers are often computationally expensive and computationally less expensive methods typically fail to capture crucial physical phenomena such as finite-speed acoustic waves. We present a novel DEM–CFD framework for low-Mach number flows that couples the Discrete Element Method (DEM) with a non-iterative, weakly-compressible fractional-step method for the gas phase. This approach combines the particle-scale accuracy of DEM with a gas solver that efficiently handles both density variations and acoustic wave propagation. As a fundamental step before simulating reactive flows, this paper validates the framework’s hydrodynamic and acoustic capabilities using non-reactive test cases. First, simulations of pressure drop across a fixed bed show excellent agreement with the Ergun equation, validating the momentum exchange model. Second, the complex dynamics of a spout-fluidized bed are shown to reproduce experimental trends, while also highlighting the simulation’s sensitivity to particle contact parameters like restitution and friction coefficients. Finally, speed of sound measurements in various gases (Dry Air, CO

_{2}

, H

_{2}

) within a particle bed confirm the framework’s ability to accurately capture finite sound speed and species-dependent properties, with results aligning well with pure-gas theory. The framework’s flexibility was further demonstrated by successfully reproducing an alternative ”frozen” two-phase sound speed. These comprehensive validations demonstrate the framework’s capability as a robust and efficient tool for investigating complex reactive multiphase flows.

大型多相反应器（如甲烷化流化床）的设计需要计算效率高、物理精度高的数值方法。该研究解决了现有方法的局限性，传统的DEM-CFD求解器通常计算成本昂贵，而计算成本较低的方法通常无法捕获关键的物理现象，如有限速度声波。我们提出了一种新的低马赫数流动的DEM - cfd框架，该框架将离散元法（DEM）与气相的非迭代、弱可压缩分步法相结合。该方法将DEM的粒子尺度精度与气体求解器相结合，有效地处理密度变化和声波传播。作为模拟反应性流之前的基本步骤，本文使用非反应性测试用例验证了框架的水动力和声学能力。首先，固定床上压降的模拟结果与Ergun方程非常吻合，验证了动量交换模型。其次，喷流化床的复杂动力学可以再现实验趋势，同时也突出了模拟对颗粒接触参数（如恢复和摩擦系数）的敏感性。最后，对颗粒床内不同气体（干燥空气、二氧化碳、氢气）的声速进行测量，证实了该框架能够准确捕捉有限声速和物种相关特性，结果与纯气体理论非常吻合。通过成功再现另一种“冻结”两相声速，进一步证明了该框架的灵活性。这些全面的验证证明了该框架作为研究复杂反应多相流的强大而有效的工具的能力。

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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 : 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

Enhancement of pool boiling heat transfer using eco-hybrid nanofluids 生态混合纳米流体增强池沸腾传热

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2025-11-24 DOI: 10.1016/j.ijmultiphaseflow.2025.105559

Raju Kumar , Pravin Pranav , Rinku Kumar Gouda , Akash Priy , Manabendra Pathak , Mohd. Kaleem Khan , Md. Shamim Shah

This draft explores an experimental investigation into improving pool boiling heat transfer through the use of eco-friendly hybrid nanofluids. The proposed eco-friendly hybrid nanofluids have been prepared using Rhamnolipid surfactant particles, Magnesium Oxide (MgO), and water. Four samples of hybrid nanofluids have been prepared by keeping Rhamnolipid surfactant at the critical micelles concentration and by varying the MgO concentrations as 0.5g/l, 0.05g/l, 0.005g/l, and 0.0005 g/l in deionized water. The detailed characterization and stability analysis of the hybrid nanofluids were performed. Roughness and wettability of fresh and post-boiling surfaces have been analyzed to check their influence on the heat transfer process. The hybrid nanofluid has a thermal conductivity of 4-9 % greater than DI water, where its surface tensions are 43 % - 53 % lower than those of pure DI water. The investigations were carried out on a smooth copper surface and at atmospheric conditions. The developed hybrid nanofluid enhances both the heat transfer rate and the critical heat flux (CHF) compared to pure water. The heat transfer coefficient (HTC) is observed to increase by 1.16 to 1.79 times, and the CHF is increased by 1.41 to 1.61 times. The result for improved heat transfer in eco-hybrid nanofluids is due to the decrease in surface tension, which has initiated more nucleation sites than pure water, increase in porosity and surface roughness due to the deposition of nanoparticles and surfactant monomers, improved surface wettability, and better rewetting phenomena.

本草案探讨了通过使用生态友好型混合纳米流体改善池沸腾传热的实验研究。采用鼠李糖脂表面活性剂颗粒、氧化镁（MgO）和水制备了环保型混合纳米流体。将鼠李糖脂表面活性剂保持在临界胶束浓度，在去离子水中MgO浓度分别为0.5g/l、0.05g/l、0.00g /l和0.0005 g/l，制备了4种杂化纳米流体样品。对混合纳米流体进行了详细的表征和稳定性分析。分析了新鲜表面和沸腾后表面的粗糙度和润湿性，以检查它们对传热过程的影响。混合纳米流体的导热系数比去离子水高4- 9%，其表面张力比纯去离子水低43% - 53%。研究是在光滑的铜表面和大气条件下进行的。与纯水相比，混合纳米流体的传热速率和临界热流密度均有所提高。传热系数（HTC）增加了1.16 ~ 1.79倍，CHF增加了1.41 ~ 1.61倍。生态杂化纳米流体传热改善的结果是由于表面张力的降低（与纯水相比，表面张力产生了更多的成核位点）、纳米颗粒和表面活性剂单体的沉积增加了孔隙度和表面粗糙度、表面润湿性的改善以及更好的再润湿现象。

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引用次数: 0

Beyond the Cassie–Baxter model: New insights for predicting imbibition in complex systems 超越Cassie-Baxter模型：预测复杂系统渗吸的新见解

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2025-11-24 DOI: 10.1016/j.ijmultiphaseflow.2025.105560

Mathis Fricke , Lisanne Gossel , Joël De Coninck

We revisit the classical problem of liquid imbibition in a single tube with spatially varying wettability. Starting from the Lucas–Washburn equation, we derive analytical solutions for the imbibition time (crossing time) in systems where wettability alternates between different materials. For ordered arrangements, we demonstrate that the imbibition speed depends non-trivially on the spatial distribution, with the ”more hydrophobic-first” configuration being optimal. For disordered systems, where segment lengths follow a Gaussian distribution, we show that the classical Cassie–Baxter contact angle, originally derived for static wetting, fails to predict the dynamics of capillary-driven flow. To address this, we propose a new weighted harmonic averaging method for the contact angle, which accurately describes the viscous crossing time in such heterogeneous systems. Our findings reveal fundamental insights into the role of wettability heterogeneity in capillary-driven flow, offering a basis for understanding imbibition dynamics in complex heterogeneous systems.

The research data and the software supporting this study are openly available at DOI:10.5281/zenodo.14537452.

我们重新审视了具有空间变化润湿性的单管中液体吸吮的经典问题。从Lucas-Washburn方程出发，我们推导出了不同材料之间润湿性交替的系统中吸胀时间（穿越时间）的解析解。对于有序排列，我们证明了吸胀速度与空间分布有很大关系，“更疏水优先”的配置是最优的。对于片段长度服从高斯分布的无序系统，我们表明，最初为静态润湿导出的经典Cassie-Baxter接触角无法预测毛细管驱动流动的动力学。为了解决这个问题，我们提出了一种新的加权谐波平均接触角方法，该方法可以准确地描述这种非均质系统中的粘性穿越时间。我们的研究结果揭示了润湿性非均质性在毛细管驱动流体中的作用，为理解复杂非均质系统中的吸胀动力学提供了基础。研究数据和支持本研究的软件可在DOI:10.5281/zenodo.14537452上公开获取。

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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 : 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

Particle-laden gravity currents: The lock-release slumping regime at the laboratory scale 满载粒子的重力流：实验室尺度下的锁释塌缩状态

IF 3.8 2区工程技术 Q1 MECHANICS

International Journal of Multiphase Flow

Pub Date : 2025-11-20 DOI: 10.1016/j.ijmultiphaseflow.2025.105539

C. Gadal , J. Schneider , C. Bonamy , J. Chauchat , Y. Dossmann , S. Kiesgen de Richter , M.J. Mercier , F. Naaim-Bouvet , M. Rastello , L. Lacaze

This study investigates the early slumping regime of particle-laden gravity currents from full-depth dam-break releases, combining laboratory experiments and two-fluid simulations. By systematically exploring the parameter space, it highlights the influence of the bottom slope, particle volume fraction and particle settling velocity on the flow dynamics.

本研究结合实验室实验和双流体模拟，研究了全深度溃坝释放中载重粒子重力流的早期滑塌状态。通过系统地探索参数空间，突出了底部坡度、颗粒体积分数和颗粒沉降速度对流动动力学的影响。

引用次数: 0