International Journal of Heat and Mass Transfer最新文献_第9页

A comparative study on the effects of external and internal dry cooling zones on the performance of hybrid natural draft cooling towers 外冷区与内冷区对混合式自然通风冷却塔性能影响的比较研究

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-01-10 DOI: 10.1016/j.ijheatmasstransfer.2026.128354

Weipeng Deng , Zhufeng Lin , Huinan Yang , Fengzhong Sun , Huaqiang Chu

Due to the lack of quantitative evaluation methods for plumes, the design of plume control for large wet cooling towers still faces significant challenges. This study uses the outlet surface of cooling towers as the reference and proposes methods for calculating the plume area and the mass flow rate of the plume. Furthermore, a comparative analysis is conducted on the impact of internal (IN_DCZ) and external (EX_DCZ) dry cooling zones on the performance of hybrid cooling towers. Under wind conditions, the performance of IN_DCZ is better than that of EX_DCZ. Compared to EX_DCZ, the outlet water temperature of IN_DCZ reduces by 0.4 °C, the water-saving rate of IN_DCZ increases by 2.2%, and the area and mass flow rate of plume for IN_DCZ are reduced by 45.5 % (663.3 m²) and 50.3 % (6969.7 kg/s), respectively. When the inlet water ratio of the dry cooling zone exceeds 70 %, the plume control capability of IN_DCZ far exceeds that of EX_DCZ, reducing the plume area and mass flow rate by 98.2 % (1054.1 m²) and 98.7 % (9989.2 kg/s) compared to EX_DCZ. This study provides an application exploration for precise plume control in large wet cooling towers.

由于缺乏对羽流的定量评价方法，大型湿式冷却塔的羽流控制设计仍然面临着很大的挑战。本研究以冷却塔出口表面为参照，提出了羽流面积和羽流质量流量的计算方法。对比分析了内（IN_DCZ）和外（EX_DCZ）干冷区对混合式冷却塔性能的影响。在风力条件下，IN_DCZ的性能优于EX_DCZ。与EX_DCZ相比，IN_DCZ的出水温度降低了0.4℃，节水率提高了2.2%，羽流面积和质量流量分别减少45.5% （663.3 m2）和50.3% （6969.7 kg/s）。当干冷区进水比超过70%时，IN_DCZ的羽流控制能力远远超过EX_DCZ，羽流面积和质量流量比EX_DCZ分别减少98.2% （1054.1 m2）和98.7% （9989.2 kg/s）。本研究为大型湿式冷却塔羽流精确控制提供了应用探索。

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引用次数: 0

Boiling dynamics on well-ordered porous layers: A lattice Boltzmann simulation study 有序多孔层上的沸腾动力学：晶格玻尔兹曼模拟研究

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-01-10 DOI: 10.1016/j.ijheatmasstransfer.2026.128367

Hengyu Hu, Haibo Huang

This study investigates pool boiling enhanced by the well-ordered porous layers using direct numerical simulations based on a coupled lattice Boltzmann method (LBM) and finite difference method (FDM). The simulations capture the dynamic behavior of the vapor–liquid interface during boiling. A physical model is developed to establish a scaling law relating the thickness of porous layers

H

to critical boiling times. Specifically, the inception time

t_{i}

, phase change time

t_{p}

, and gross boiling time

t_{g}

all exhibit a quadratic dependence on

H

. Furthermore, the study shows that under certain conditions, boiling bypasses the nucleate and transition regimes and proceeds directly to film boiling, resulting in the absence of a critical heat flux (CHF). This phenomenon is explained using Rayleigh–Taylor instability theory, from which a criterion is derived to predict the existence of CHF based on the relationship between the critical instability wavelength and the spacing between nucleation sites. The findings offer new insight into boiling mechanisms on porous layers and provide theoretical guidance for designing thermally efficient porous structures.

基于晶格玻尔兹曼法（LBM）和有限差分法（FDM）的直接数值模拟研究了有序多孔层对池沸腾的促进作用。模拟捕获了沸腾过程中汽液界面的动态行为。建立了一个物理模型，建立了多孔层厚度H与临界沸腾时间之间的标度规律。具体而言，起始时间ti、相变时间tp和总沸腾时间tg均与h呈二次依赖关系。此外，研究表明，在某些条件下，沸腾绕过核态和过渡态，直接进入膜态沸腾，导致没有临界热流密度（CHF）。用瑞利-泰勒不稳定性理论解释了这一现象，并根据临界不稳定性波长与成核位间距之间的关系，导出了预测CHF存在的判据。研究结果为研究多孔层的沸腾机理提供了新的思路，并为设计热效率高的多孔结构提供了理论指导。

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引用次数: 0

Modeling on thermal conductivity of petroleum hydrocarbons-contaminated soils considering preferential invasion pores and connection patterns 考虑优先侵入孔隙和连接模式的石油烃污染土壤导热系数建模

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-01-10 DOI: 10.1016/j.ijheatmasstransfer.2026.128348

Jun Bi , Huiqi Xia , Sheng Yang , Shengnian Wang , Tingting Wei , Wansheng Pei

Petroleum hydrocarbons (PHs) are compounds containing the elements carbon and hydrogen. The leaks of PHs during the PHs exploration, transportation, refining, and storage process usually contaminate the site, disrupt ecological environment and threaten human health. Therefore, the in-situ thermal desorption technology has been widely used to heat the contaminated sites and remove the pollutants, but the contaminants removal efficiency is controlled by thermal conductivity (TC) in the contaminated site. In this study, a theoretical model was developed by using different preferential invasion pores (i.e., parallel and series pores) and connection patterns between air and liquid mixture of water and PHs (i.e., parallel and series connections). The new model was expressed as a function of porosity, temperature, degree of saturation of PHs, and degree of saturation of water. The theoretical model was evaluated with TC values of diesel-contaminated soils, and good agreements between estimated and measured TC values were obtained. Moreover, all the estimated TC values determined by the new model strictly fall within the Wiener bounds, and most estimated TC results fall within the Hashin-Shtrikman bounds. The theoretical TC model will contribute to the understanding of heat transfer process in the PHs-contaminated site during the remediation process.

石油碳氢化合物（PHs）是含有碳和氢元素的化合物。小灵通在勘探、运输、提炼和贮存过程中发生泄漏，污染场地，破坏生态环境，威胁人体健康。因此，原位热解吸技术已被广泛用于对污染场地进行加热和去除污染物，但污染物的去除效率受污染场地的导热系数（TC）的控制。本研究利用不同优先侵入孔隙（即并联和串联）以及水与ph气液混合物的连接方式（即并联和串联）建立了理论模型。新模型表示为孔隙度、温度、ph饱和度和水饱和度的函数。用柴油污染土壤的TC值对理论模型进行了评价，得到了较好的TC值估计值和实测值。此外，新模型确定的所有估计TC值都严格落在Wiener界内，大多数估计TC结果落在Hashin-Shtrikman界内。理论TC模型将有助于理解修复过程中ph污染场地的传热过程。

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引用次数: 0

Physics-informed neural networks for 2D-transient inverse heat conduction problem involving static and moving heat source 涉及静态和移动热源的二维瞬态反热传导问题的物理神经网络

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.ijheatmasstransfer.2026.128349

M.S. Bidou, J.-G. Bauzin, N. Laraqi

In thermal engineering, the effectiveness of diagnosis, monitoring, and control depends on accurately identifying material properties and locating internal heat sources from limited temperature measurements. This work advances a physics-based hybrid learning framework for 2D thermal conduction, which combines data and physical priors to stabilize inference under limited measurement conditions. We address two complementary objectives: (i) thermophysical identification within an orthotropic medium, estimating the in-plane conductivity tensor

Λ = diag (λ_{x}, λ_{y})

and the volumetric heat capacity

ρ C

(with diffusivity reported a posteriori); and (ii) internal volumetric heat-source identification in an isotropic medium, recovering the Gaussian source’s flux amplitude, spatial position, and spatial dispersion, for both fixed and mobile centers. A PINN-based sensitivity analysis guides sensor placement to enhance identifiability with few measurements. Performance is evaluated on noise-free data and under additive Gaussian sensor noise (0.1 K and 0.5 K). Across both settings, the approach delivers high accuracy for material parameters and source localization, and low errors for source flux, supporting robust thermal inverse diagnostics with minimal instrumentation.

在热能工程中，诊断、监测和控制的有效性取决于准确识别材料特性和从有限的温度测量中定位内部热源。这项工作提出了一个基于物理的二维热传导混合学习框架，它结合了数据和物理先验，以稳定有限测量条件下的推断。我们解决了两个互补的目标：(i)在正交异性介质中进行热物理识别，估计平面内导热张量Λ=diag（Λ x， Λ y）和体积热容量ρC（后验报告扩散率）；（ii）在各向同性介质中进行内部体积热源识别，恢复固定和移动中心高斯源的通量振幅、空间位置和空间色散。基于pup的灵敏度分析指导传感器放置，以提高识别性与很少的测量。在无噪声数据和加性高斯传感器噪声（0.1 K和0.5 K）下评估性能。在这两种设置中，该方法提供了材料参数和源定位的高精度，并且源通量的误差很低，支持用最少的仪器进行强大的热逆诊断。

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引用次数: 0

Numerical investigation on flow instability of supercritical n-decane in a vertical upward tube with pyrolysis effects 超临界正癸烷在垂直向上管内流动不稳定性的数值研究

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.ijheatmasstransfer.2026.128342

Songbo Nan , Zeyuan Cheng , Xiang Li , Jingsong Huang , Jianqin Zhu

Flow instability of supercritical hydrocarbon fuels in regenerative cooling channels is a critical issue faced by scramjet engines. Existing research has largely overlooked the influence of pyrolysis on flow instability. This work numerically investigated the instability behaviors and mechanism of supercritical n-decane in a vertical tube, emphasizing the effects of inlet flow rate and pyrolysis. The instability boundaries under different pressures were also established. The results show that the pressure-drop curve exhibits a quintic behavior with two negative-slope regions, caused by sharp density variations in the pseudo-critical and pyrolysis temperature regions. At an inlet flow rate of 0.8 g/s, the fuel exhibits periodic density-wave oscillation at a frequency of 0.23 Hz. Density variation is the fundamental cause of instability, while buoyancy and pyrolysis act as key factors of the periodic oscillations. As the inlet mass flow rate increases from 0.41 g/s to 1.2 g/s, the instability evolves from flow drift coupled with density-wave oscillations to pure density-wave oscillations, and eventually to stable flow, with stability initially decreasing and then increasing. Pyrolysis transforms the pressure drop curve from a cubic to a quintic behavior, which in turn alters the mode of flow instability in the negative-slope regions of the pressure drop curve and shortens the oscillation period from 4.5 s to 4.3 s. The predicted flow instability boundaries under 2.5–4.0 MPa show a maximum deviation of 9.3 % from experimental data. These findings provide theoretical guidance for the safe and reliable design of regenerative cooling channels.

超临界碳氢燃料在再生冷却通道中的流动不稳定性是超燃冲压发动机面临的一个关键问题。现有研究在很大程度上忽略了热解对流动不稳定性的影响。本文对超临界正癸烷在垂直管内的不稳定行为和机理进行了数值研究，重点研究了入口流速和热解的影响。建立了不同压力下的不稳定边界。结果表明：由于准临界温度区和热解温度区密度的急剧变化，压降曲线呈现出具有两个负斜率区域的五次曲线特征；在进口流量为0.8 g/s时，燃料表现出频率为0.23 Hz的周期性密度波振荡。密度变化是不稳定的根本原因，而浮力和热解是周期性振荡的关键因素。当进口质量流量从0.41 g/s增加到1.2 g/s时，不稳定性从流动漂移耦合密度波振荡发展到纯密度波振荡，最终发展到稳定流动，稳定性先降低后增加。热解使压降曲线由三次行为转变为五次行为，从而改变了压降曲线负斜率区域的流动不稳定模式，振荡周期由4.5 s缩短至4.3 s。在2.5 ~ 4.0 MPa范围内，预测的流动不稳定边界与实验数据的最大偏差为9.3%。研究结果为安全可靠地设计蓄热式冷却通道提供了理论指导。

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引用次数: 0

Binary collisions between slurry droplets at different ambient temperatures 浆液液滴在不同环境温度下的二元碰撞

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.ijheatmasstransfer.2026.128327

Anastasia Islamova, Svetlana Kropotova, Andrey Klimenko, Stanislav Shulyaev

Understanding the specific aspects of binary interactions of coal-water slurry droplets is crucial for optimizing the transportation of this fuel and spraying in industrial applications. This research presents experimental findings for binary collisions of coal-water slurry droplets, when varying the ambient air temperature (from 25 to 200°C), concentration of solid coal particles (from 0.5 to 5%), and geometry of collisions. Using high-speed video recording, the following interaction regimes of droplets were recorded: bounce, coalescence, reflexive separation, and stretching separation. Droplet interaction regime maps were plotted to identify the boundaries between regimes depending on the solid phase concentration in the slurry and ambient temperature. The probability of occurrence of a regime was not significantly dependent on the coal concentration in the slurry in the considered range, but was very sensitive to the impact angle and velocity. It was hypothesized that the geometry of the lamella forming in off-center interaction determines the number of secondary fragments (child droplets) after its breakup. The inertial forces of droplets and thermophysical properties of the gas medium rather than the solid phase concentration in the liquid have a decisive effect on the droplet interaction outcome.

了解水煤浆液滴二元相互作用的具体方面对于优化这种燃料的运输和工业应用中的喷涂至关重要。本文研究了不同环境空气温度（25 ~ 200℃）、固体煤颗粒浓度（0.5 ~ 5%）和碰撞几何形状对水煤浆液滴二元碰撞的实验结果。采用高速录像技术，记录了液滴的弹跳、聚并、反射分离、拉伸分离等相互作用过程。根据浆液中固相浓度和环境温度，绘制了液滴相互作用状态图，以确定状态之间的边界。在考虑的范围内，一种状态发生的概率与浆体中煤的浓度无关，但对冲击角和冲击速度非常敏感。据推测，在离中心相互作用中形成的薄片的几何形状决定了其破裂后的次级碎片（子液滴）的数量。液滴的惯性力和气体介质的热物理性质，而不是液体中固相浓度，对液滴相互作用的结果有决定性的影响。

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引用次数: 0

Interface and structure effects on thermal properties and phase-change characteristics of chloride-based CPCMs toward sustainable thermal storage 界面和结构对氯基cpcm热性能和相变特性的影响

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.ijheatmasstransfer.2026.128333

Youping Li , Yue Kuang , Shuang Ma , Xuxia Sun , Zheng Jiang , Han Jiang , Qirong Yang

ZnCl₂-NaCl-KCl eutectic salt is considered a promising latent heat phase change material (PCM) that exhibits significant potential for development and application in thermal energy storage systems. However, given its strong corrosiveness and high propensity for leakage, it is typically encapsulated within porous framework materials to enhance stability and safety during practical applications. Different pore structures and framework types can significantly impact the thermal behavior and phase change characteristics in composite phase change materials (CPCMs) through interfacial interactions and structural configurations. However, research on the structure and interface effects of chloride-based salts remains scarce, and their underlying mechanisms on these effects within CPCMs are not yet fully elucidated. In this study, interfacial effects on thermal behavior and phase change characteristics of ZnCl₂-NaCl-KCl eutectic salts were systematically explored by integrating the molecular dynamics (MD) simulation with experimental analyses. Additionally, the structural effects on thermal behavior and phase-change characteristics of ternary chloride salts mixture were explored using MD simulations. The results indicate that the interfacial and structural effects are primarily influenced by the ionic structure and interfacial binding energy. Among various interfacial composite models, the salt on Al₂O₃ composite material exhibits the highest thermal conductivity, specific heat capacity, and latent heat of phase change. Among various structural composite models, the ink-bottle shaped CPCMs achieve higher thermal conductivity than that of the pure chloride salts and other CPCM structures. The specific heat capacity follows a similar trend to the thermal conductivity. The ink-bottle shaped pore structure of the Al₂O₃ framework is identified as the most appropriate configuration for accommodating the ZnCl₂-NaCl-KCl eutectic salt.

ZnCl2-NaCl-KCl共晶盐被认为是一种很有前途的潜热相变材料（PCM），在热能储存系统中具有重要的开发和应用潜力。然而，由于其强腐蚀性和高泄漏倾向，通常将其封装在多孔框架材料中，以提高实际应用中的稳定性和安全性。不同的孔隙结构和骨架类型可以通过界面相互作用和结构构型显著影响复合相变材料的热行为和相变特性。然而，关于氯基盐的结构和界面效应的研究仍然很少，并且它们在cpcm中对这些效应的潜在机制尚未完全阐明。本研究采用分子动力学模拟与实验分析相结合的方法，系统探讨了界面效应对ZnCl2-NaCl-KCl共晶盐热行为和相变特性的影响。此外，还研究了结构对三元氯化物混合物热行为和相变特性的影响。结果表明，离子结构和界面结合能是影响界面和结构效应的主要因素。在各种界面复合模型中，Al2O3上盐复合材料的导热系数、比热容和相变潜热最高。在多种结构复合模型中，墨水瓶型CPCM比纯氯盐和其他CPCM结构具有更高的导热性。比热容的变化趋势与导热系数的变化趋势相似。Al2O3骨架的墨水瓶状孔结构是容纳ZnCl2-NaCl-KCl共晶盐最合适的结构。

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引用次数: 0

A modular conjugate heat transfer optimization framework for thermal management of electric aircraft 面向电动飞机热管理的模块化共轭传热优化框架

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.ijheatmasstransfer.2026.128345

Christian Psenica , Lean Fang , Seth Zoppelt , Mark Leader , Ping He

Conjugate heat transfer (CHT) analysis and optimization is a powerful method for improving thermal management as it simultaneously resolves the temperature distribution in both fluid and solid domains. This paper presents a modular, discrete adjoint-based CHT optimization capability integrated within the OpenMDAO/MPhys framework. A unique feature of the proposed framework is its flexibility to extend to multidisciplinary optimization, including aero-structural-thermal applications. The fluid domain is modeled using a finite-volume Computational Fluid Dynamics (CFD) solver, and the solid domain with a conduction heat transfer solver. A mixed Neumann-Dirichlet boundary condition is developed to enable full submersion of the solid geometry within the fluid domain, while ensuring consistent temperature and heat flux coupling at the CHT interface. Gradient-based optimization is performed; the gradients are efficiently computed using the discrete adjoint solvers implemented in DAFoam. To demonstrate the method, this paper considers two cases related to electric aircraft thermal management: a U-bend heat exchanger and an actively cooled battery pack. The U-bend case aims to minimize pressure loss while maximizing heat flux by changing the pipe geometry. The optimized design reduces pressure loss by 52.7% and increases total heat flux by 2.3%. In the battery pack case, a 3-by-3 cell configuration is cooled by ambient airflow, with constant heat generation prescribed in the cells. The battery casing shape serves as the design variable, and the objective function is a weighted sum of pressure loss and pack weight, subject to a maximum temperature constraint. The optimized design achieves a 44.6% reduction in pressure loss and a 1.5% reduction in weight, while satisfying the thermal constraint. To ensure the reliability of the optimized designs, this study validates coarse-mesh, steady-state predictions against fine-mesh unsteady simulations, demonstrating consistency within acceptable errors. This work demonstrates the potential of the developed framework to enable rapid, high-fidelity design of thermal management systems for electric aircraft.

共轭传热（CHT）分析和优化是一种有效的热管理方法，因为它同时解决了流体和固体领域的温度分布。本文提出了一种集成在OpenMDAO/MPhys框架中的模块化的、离散的、基于伴随的CHT优化能力。所提出的框架的一个独特之处在于其扩展到多学科优化的灵活性，包括空气-结构-热应用。流体领域采用有限体积计算流体动力学（CFD）求解器，固体领域采用传导传热求解器。提出了一种混合诺伊曼-狄利克雷边界条件，使固体几何结构完全浸入流体域中，同时确保在CHT界面处温度和热流耦合一致。进行基于梯度的优化；利用DAFoam实现的离散伴随解算器有效地计算了梯度。为了演示该方法，本文考虑了与电动飞机热管理相关的两个案例：u型换热器和主动冷却电池组。u型套管的目的是通过改变管道的几何形状来最大限度地减少压力损失，同时最大化热通量。优化后的压力损失降低了52.7%，总热流密度提高了2.3%。在电池组的情况下，一个3 × 3的电池配置由环境气流冷却，在电池中规定恒定的热量产生。电池外壳形状作为设计变量，目标函数是压力损失和包重的加权和，受最高温度约束。优化后的设计在满足热约束的情况下，压力损失降低44.6%，重量减轻1.5%。为了确保优化设计的可靠性，本研究验证了粗网格、稳态预测和细网格非定常模拟，在可接受的误差范围内证明了一致性。这项工作证明了开发框架的潜力，可以实现电动飞机热管理系统的快速、高保真设计。

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引用次数: 0

Reduced integration coupled with Monte Carlo ratios method for radiative heat transfer in cylindrical participating media 圆柱形参与介质中辐射传热的简化积分耦合蒙特卡罗比值法

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.ijheatmasstransfer.2026.128329

Amin Song , Zhi Yi , Wenchao Ji , Xin Zhang , Xin Guo , Shuangcheng Sun , Linyang Wei , Guojun Li

The Zone Method (ZM) known for high accuracy plays a critical role in solving the radiative heat transfer (RHT) in the high-temperature industrial fields. However, this method still faces challenges in handling high-dimensional integrals for direct exchange areas (DEAs), while having limitations in solving total exchange areas (TEAs) for anisotropic scattering media based on traditional integration method (IM). To address this issue, a reduced integration coupled with Monte Carlo ratios method (RIMCR) is developed to solve the RHT in cylindrical participating media in this study. In this method, the reduced integration scheme (RIS) is used to reduce dimension of DEAs integral formulation for cylindrical geometry, and the proportionality coefficients derived from the DEAs are employed to solve the TEAs iteratively, in which the iterative ratios of gas micro-elements within anisotropic scattering media are determined via tracking the path of energy beams by Monte Carlo method (MCM). A series of cases in two-dimensional axisymmetric configurations with uniform medium properties demonstrates the RIMCR not only has high accuracy, but also significantly improves computational efficiency in solving the two-dimensional cylindrical RHT. Notably, RIMCR achieves a computational efficiency improvement exceeding 75 % compared to the IM. Therefore, RIMCR is a reliable method for effective and accurate solution of the RHT in participating media.

区域法（ZM）以其高精度而闻名，在高温工业领域的辐射传热求解中起着至关重要的作用。然而，该方法在处理直接交换面积（dea）的高维积分时仍然存在挑战，而在求解各向异性散射介质的总交换面积（TEAs）时，基于传统积分法（IM）存在局限性。为了解决这一问题，本研究开发了一种简化积分耦合蒙特卡罗比率法（RIMCR）来求解圆柱形参与介质中的RHT。该方法采用降阶积分格式（RIS）对圆柱几何的DEAs积分公式进行降维，利用DEAs得到的比例系数进行迭代求解，通过蒙特卡罗方法（MCM）跟踪能量束的路径来确定各向异性散射介质中气体微量元素的迭代比。一系列具有均匀介质性质的二维轴对称构型的算例表明，RIMCR不仅具有较高的精度，而且显著提高了求解二维圆柱形RHT的计算效率。值得注意的是，与IM相比，RIMCR的计算效率提高了75%以上。因此，RIMCR是有效、准确地解决参与介质中RHT的可靠方法。

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引用次数: 0

Experimental and numerical studies on the heat transfer enhancement of the bifurcation windward bend structure 分岔迎风弯结构强化传热的实验与数值研究

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-01-09 DOI: 10.1016/j.ijheatmasstransfer.2026.128338

Benchi Liu , Jing Wang , Akira Nakayama , Zihao Zheng

In this study, a systematic three-dimensional numerical study and experimental study were conducted for forced convection in a series of isothermally heated bifurcation windward bend structures. The numerical experiment was based on an in-house computer program with the Semi-implicit Method for Pressure-linked Equation (SIMPLE algorithm) and Finite Volume Method (FVM) to solve the continuity equation, Navier-Stokes equation, and energy equation of the fluid phase and solid phase. The heat transfer performance of various bifurcation windward bend structures was investigated by using experimental method and compared the results with numerical simulation. It shows numerical results and experimental results match well, the error between these two is less than 10%. A set of Nusselt numbers under equal Reynolds numbers and pumping powers were calculated to investigate the impact of structural optimization on enhancing heat transfer performance. The results point out the bifurcated windward bend structure with

θ = 30^{\circ}

that provides the best heat transfer performance. This structure exhibits excellent heat transfer performance due to its high thermal dispersion and low flow resistance. This numerical study provides evidence that the bifurcation design strategy is an effective method to design and optimize heat exchanger systems.

本文对一系列等温加热分岔迎风弯结构中的强迫对流进行了系统的三维数值研究和实验研究。数值实验基于内部编制的计算机程序，采用压力链接方程半隐式方法（SIMPLE算法）和有限体积法（FVM）求解流体相和固相的连续性方程、Navier-Stokes方程和能量方程。采用实验方法研究了不同分岔迎风弯结构的换热性能，并与数值模拟结果进行了比较。结果表明，数值结果与实验结果吻合较好，两者误差小于10%。计算了等雷诺数和泵浦功率下的一组努塞尔数，研究了结构优化对提高传热性能的影响。结果表明，θ=30°的分叉迎风弯曲结构具有最佳的传热性能。该结构具有高的热分散和低的流动阻力，具有优良的传热性能。数值研究表明，分岔设计策略是换热器系统设计和优化的有效方法。

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引用次数: 0