International Journal of Heat and Mass Transfer最新文献_第4页

Experimental and numerical investigation on the heat transfer and flow characteristics of airfoil-shaped twisted hexagonal tubes 翼型扭曲六方管传热与流动特性的实验与数值研究

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-11 DOI: 10.1016/j.ijheatmasstransfer.2026.128503

Dongyang Shao , Ailong Yuan , Hui Wan , Guofeng Guan , Jie Ma , Changsong Wang

As a critical component in energy transfer systems, heat exchangers play a vital role in achieving energy conservation and emission reduction. Building on previous studies of the heat transfer and flow behavior of twisted hexagonal tube heat exchangers, this study proposes six novel airfoil-inspired twisted hexagonal tube configurations, including outward convex non-deviated, outward convex left/right-deviated, inward concave non-deviated, and inward concave left/right-deviated airfoil-shaped designs. Numerical simulations employing the Realizable k-ε turbulence model were performed to systematically evaluate the heat transfer performance and flow characteristics of these configurations. The optimal configuration was identified, and the effects of key geometric parameters on thermo-hydraulic performance were systematically analyzed to guide structural optimization of the proposed designs. The results indicate that, under the synergistic interaction between the airfoil orientation and the tube twisting direction, vortex structures are induced near the airfoil regions, generating strong secondary flows. These flows significantly enhance momentum exchange and mixing between the hot and cold fluids across the boundary layer, thereby improving the convective heat transfer capability of the twisted tube. Compared with the conventional, the outward convex left-deflected airfoil-shaped twisted hexagonal tube exhibits the most favorable thermo-hydraulic performance. After optimization, the average Nusselt number increases by 45.94 %, with a maximum improvement of 49.53 %, while the average friction factor rises by 61.59 %. The overall performance evaluation criterion reaches a maximum value of 1.29, which indicates an overall thermo-hydraulic performance superior to that of several enhanced tube configurations reported in the open literature, such as elliptical twisted tubes, corrugated tubes, dimpled tapered tubes, and multi-start helical corrugated tubes. This study establishes a theoretical foundation for the design and optimization of high-efficiency twisted-tube heat exchangers.

换热器作为能量传递系统的关键部件，在实现节能减排方面起着至关重要的作用。基于以往对扭曲六角形管换热器传热和流动特性的研究，本研究提出了六种新型翼型启发的扭曲六角形管构型，包括外凸非偏、外凸左/右偏、内凹非偏和内凹左/右偏翼型设计。采用Realizable k-ε湍流模型进行了数值模拟，系统地评估了这些构型的传热性能和流动特性。确定了最优配置，系统分析了关键几何参数对热工性能的影响，指导了所提设计的结构优化。结果表明，在翼型方向和管扭方向的协同作用下，翼型区域附近会产生涡结构，产生强烈的二次流。这些流动显著增强了边界层上冷热流体的动量交换和混合，从而提高了扭管的对流换热能力。与常规管型相比，外凸左偏转翼型扭曲六角形管具有较好的热工性能。优化后，平均努塞尔数提高45.94%，最大提高49.53%，平均摩擦系数提高61.59%。综合性能评价指标达到最大值1.29，表明其综合热水力性能优于公开文献中报道的几种增强管构型，如椭圆扭管、波纹管、凹陷锥形管和多启动螺旋波纹管。该研究为高效扭管换热器的设计与优化奠定了理论基础。

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引用次数: 0

Effect of sintering temperature on the microstructure, composition, and heat transfer of the GaN/diamond interface 烧结温度对氮化镓/金刚石界面微观结构、成分和传热的影响

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-01-29 DOI: 10.1016/j.ijheatmasstransfer.2026.128447

Weishuai Sun , Xiaoqin Guo , Yabo Huang , Shengji Liu , Yuehan Yue , Xulei Wang , Shuai Tian , Xin Jia , Kang An , Zhengyi Zhang , Zhen Liu , Lin Gao

Gallium nitride (GaN) and a chemical vapour deposition (CVD) diamond were bonded using a semisolid nano-silver paste under low-temperature, pressure-assisted conditions. The effect of sintering temperature on the microstructure and mechanical properties of the GaN/diamond interface was investigated. The results showed that the solder morphology gradually evolved from point-like to sheet-like as the sintering temperature increased. Scanning electron microscopy observations of the GaN/diamond interface revealed that the thickness of the Ag sintering layer was approximately 40 μm. Moreover, elemental analysis of the GaN/diamond side of the sintered interface indicated a diffusion tendency of Ag. A well-defined planar interface at the nanoscale between Ag and GaN was further observed through transmission electron microscopy. The X-ray diffraction peak intensity of the Ag (111) crystal plane increased with increasing sintering temperature, while the full width at half maximum of the Ag (111) diffraction peak decreased, indicating improved nano-silver crystal quality at higher temperatures. The highest shear strength, 12.5 MPa, was obtained for samples sintered at 250°C. Interfacial solder uniformity was evaluated by monitoring the surface temperature of the heated GaN/diamond assembly, with a minimum average temperature difference of only 1.38 °C. The maximum thermal conductivity of the GaN/diamond structure reached 156.4 W/(m·K) at 250 °C. This study provides valuable insights into the heat dissipation of gallium nitride devices.

在低温、压力辅助条件下，采用半固态纳米银浆料将氮化镓（GaN）与化学气相沉积（CVD）金刚石结合。研究了烧结温度对氮化镓/金刚石界面微观结构和力学性能的影响。结果表明：随着烧结温度的升高，钎料形貌由点状逐渐演变为片状；扫描电镜观察发现，Ag烧结层厚度约为40 μm。此外，对烧结界面的氮化镓/金刚石侧进行元素分析，发现Ag有扩散趋势。通过透射电镜进一步观察到银和氮化镓之间在纳米尺度上有一个明确的平面界面。随着烧结温度的升高，Ag（111）晶面x射线衍射峰强度增大，而Ag（111）衍射峰半峰全宽减小，表明在较高温度下纳米银晶体质量得到改善。在250℃烧结时，试样的抗剪强度最高，为12.5 MPa。通过监测加热的GaN/金刚石组件的表面温度来评估界面焊料均匀性，最小平均温差仅为1.38°C。在250℃时，GaN/金刚石结构的最大导热系数达到156.4 W/（m·K）。本研究为氮化镓器件的散热提供了有价值的见解。

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引用次数: 0

Influence of thermal contact resistance and membrane electrode assembly deformation on heat and mass transfer in proton exchange membrane fuel cell with interdigitated flow fields 接触热阻和膜电极组件变形对交叉流场质子交换膜燃料电池传热传质的影响

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-01-23 DOI: 10.1016/j.ijheatmasstransfer.2026.128418

Ben-Xi Zhang , Run-Ze Niu , Kai-Qi Zhu , Yan-Ru Yang , Xiao-Dong Wang

This study establishes a three-dimensional, two-phase, non-isothermal proton exchange membrane fuel cell (PEMFC) model incorporating thermal contact resistance (TCR) and membrane electrode assembly (MEA) deformation induced by 0–30 kPa pressure differences. Using an interdigitated flow field, we systematically investigate the coupled effects of TCR thickness (0–3 µm) and pressure differential on heat transfer, oxygen transport, and water management. The results show that increasing TCR raises internal MEA temperature, reduces membrane water content, and decreases oxygen molar concentration at the gas diffusion layer (GDL)–catalyst layer (CL) interface. A moderate pressure difference (20 kPa) enhances lateral convection and evaporative cooling, mitigating temperature rise and improving oxygen availability. Polarization and power density curves indicate that performance degradation due to increased TCR can be partially offset by applying a 20 kPa pressure difference. The findings highlight the interplay between TCR and pressure difference in governing multiphase transport and electrochemical performance, offering guidance for thermal management and flow field design in PEMFC with curved MEA

本研究建立了一个三维、两相、非等温质子交换膜燃料电池（PEMFC）模型，该模型考虑了0-30 kPa压力差引起的热接触电阻（TCR）和膜电极组件（MEA）变形。利用交叉流场，我们系统地研究了TCR厚度（0-3µm）和压差对传热、氧输送和水管理的耦合影响。结果表明：TCR的增加会提高内部MEA温度，降低膜含水量，降低气体扩散层(GDL) -催化剂层（CL）界面的氧摩尔浓度；适度的压差（20 kPa）增强了侧向对流和蒸发冷却，减缓了温度升高，提高了氧气的可用性。极化和功率密度曲线表明，施加20 kPa的压差可以部分抵消TCR增加导致的性能下降。研究结果强调了TCR和压差在控制多相输运和电化学性能方面的相互作用，为弯曲MEA的PEMFC的热管理和流场设计提供了指导

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引用次数: 0

Assessment and improvement of conjugate heat transfer CFD code models of wall condensation from a gas–vapour mixture in a vertical channel 垂直通道内气-蒸汽混合物壁面凝结耦合传热CFD代码模型的评价与改进

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-07 DOI: 10.1016/j.ijheatmasstransfer.2026.128489

Patrick R. Gareau , Bronwyn Rempel , Geoffrey S. Gray , Scott J. Ormiston , Abdelouahab Dehbi

Predicting wall condensation in the presence of a non-condensable gas is of vital importance in the design of processes for refrigeration systems and in modelling passive containment cooling systems of nuclear reactors. The non-condensable gas causes a significant reduction in condensation rate and heat transfer. No consensus exists, however, on which CFD modelling approach should be used for this application.

To address this, fully conjugate heat transfer models are developed and assessed for condensation from a downward turbulent steam–air mixture flow in a primary vertical channel separated by a metal plate from a turbulent water counterflow in a secondary channel, and compared in a benchmark study. Two wall condensation modelling approaches are used in each of the commercial codes STAR-CCM+ and Fluent: (1) a sub-grid film model, which solves simplified versions of the liquid film governing equations; and (2) a user-defined wall-adjacent volumetric source term model, which neglects the fluid film. Grid-independent results for the CONAN separate effects test experiment were obtained.

A new improvement to the energy source term in the second modelling approach is presented that prevents non-physical predictions for the conjugate analysis. The Fluent custom wall-adjacent source term model reaches grid-based convergence fastest. Similar computational effort is required by all models. Model accuracies varied case-by-case, with total condensation rate maximum errors ranging from 4 to 28%. Analysis of the non-dimensional boundary layers indicate

y^{+} ≲ 1

is required to prevent excessive error. New results for the local heat transfer coefficient in the cooling channel are also presented.

不可凝性气体存在时的壁冷凝预测在制冷系统过程设计和核反应堆被动安全壳冷却系统建模中具有重要意义。不可冷凝气体导致冷凝速率和传热显著降低。然而，对于该应用哪种CFD建模方法，目前还没有达成共识。为了解决这个问题，我们开发了完全共轭传热模型，并对由金属板隔开的初级垂直通道中向下湍流的蒸汽-空气混合物流动和次级通道中湍流的水逆流的冷凝进行了评估，并在基准研究中进行了比较。商业代码STAR-CCM+和Fluent分别采用了两种壁面凝结建模方法：(1)求解简化版液膜控制方程的子网格膜模型；(2)用户定义的忽略流体膜的邻壁体积源项模型。得到了与网格无关的CONAN分离效应试验结果。对第二种建模方法中的能源项进行了新的改进，以防止共轭分析的非物理预测。Fluent自定义邻墙源项模型达到基于网格的收敛速度最快。所有模型都需要类似的计算量。模型的精度因情况而异，总凝结率的最大误差在4%到28%之间。对无量纲边界层的分析表明，为了防止过大的误差，需要y+ > 1。文中还给出了冷却通道局部换热系数的新结果。

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引用次数: 0

A novel manifold microchannel heat sink with thermal-responsive deformable fins for adaptive cooling 一种具有热响应可变形翅片的新型流形微通道散热器，用于自适应冷却

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-10 DOI: 10.1016/j.ijheatmasstransfer.2026.128481

Hang-ye Zhang , Yu-wei Wang , Zhe-hui Ma , Chuang Liu , Long Huang , Dong-yu Chen , Jin-yuan Qian

Random hotspots pose a critical threat to the thermal safety of high-flux electronic devices. The existing solutions of adaptive cooling face limitations in both regulation precision and design predictability. To address the issues, this study proposes a novel manifold microchannel (MMC) heat sink integrated with thermal-responsive deformable fin (TRDF). It leverages the inherently discrete unit of MMC heat sink to enable pixel-level cooling adjustment at targeted hotspots. The sinusoidal TRDF, constructed from a shape memory alloy (SMA) beam and elastic wrapping, is proposed for temperature-responsive deformation. When the original length of SMA beam varies, the span and height of TRDF changes differently upon heating. Thus, the thermal-hydraulic profile (THP) of unit is established, characterizing the coupled effects of inlet velocity and TRDF geometry on heat transfer coefficient and flow resistance. This THP-based methodology, combined with the flow distribution model of MMC heat sink, can identify effective deformation paths that yield significant heat dissipation adaptivity to hotspots. The results show that the horizontal configuration of TRDF can achieve stable adaptive performance, increasing the effective heat transfer coefficient by up to 14.4% under hotspot conditions. Its heat transfer coefficient also exceeds 32,700 W/m²·K. Altogether, the novel design and methodology establish a rational framework for developing predictable adaptive cooling systems of high performance.

随机热点对高通量电子器件的热安全构成严重威胁。现有的自适应冷却方案在调节精度和设计可预测性方面都存在局限性。为了解决这些问题，本研究提出了一种新型的集成了热响应可变形翅片（TRDF）的流形微通道（MMC）散热器。它利用MMC散热器固有的离散单元来实现目标热点的像素级冷却调整。正弦TRDF由形状记忆合金（SMA）梁和弹性包裹构成，提出了温度响应变形。当SMA梁的原始长度不同时，TRDF的跨度和高度随加热的变化也不同。因此，建立了机组的热-水力剖面（THP），表征了进口速度和后挡板几何形状对换热系数和流动阻力的耦合影响。这种基于thp的方法，结合MMC散热器的流动分布模型，可以识别出有效的变形路径，从而对热点产生显著的散热适应性。结果表明：在热点条件下，TRDF的水平配置可获得稳定的自适应性能，有效换热系数可提高14.4%。换热系数也超过32,700 W/m²·K。总之，新颖的设计和方法为开发可预测的高性能自适应冷却系统建立了合理的框架。

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引用次数: 0

Quantifying two-phase fluid quality through an optical supervised machine learning technique 通过光学监督机器学习技术量化两相流体质量

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-02 DOI: 10.1016/j.ijheatmasstransfer.2026.128462

Angad Panesar, William Gentry, Ian Kemp

Accurately quantifying two-phase fluid quality is essential for enhancing the efficiency and reliability of thermofluidic energy systems. This research presents a novel, non-intrusive approach to empirically estimate steam quality, using shadowgraphy imaging, combined with an innovative supervised machine learning segmentation technique. This contribution is original in adapting supervised pixel-level classification, traditionally applied in biomedical imaging, to two-phase flows, representing a cross-disciplinary methodology. The technique uniquely enables thresholding of complex steam flow interactions, including a ‘discontinuous’ annular flow. A dedicated experimental test facility enabled repeatable steam quality measurements, verified by a condensate trap, yielding a standard deviation of only 0.02. A Photron SA4 camera, operated with lower specification settings, captured 2D images through a 20 mm internal sight glass at 30 kg/h and 1.2 to 1.4 BarA. Two image segmentation approaches were evaluated for the varying compositions: an individual-trained method, where separate classifiers were developed for each quality (5 images out of 200), and a multi-condition trained method, where a generalised classifier was developed using training samples from multiple quality conditions (2 images each at 3 qualities). Using supervised machine learning tools within FIJI, steam quality estimations for both methodologies showed strong agreement with the condensate trap measurements, achieving a good accuracy within +0.02 to -0.04 over the quality range of x = 0.77 to x = 0.9. These findings demonstrate that this unique method can be integrated into real-time flow measurements, combining optical diagnostics with automated segmentation to enable accurate monitoring of flow regimes under industrial constraints.

准确地定量两相流体质量对于提高热流体能源系统的效率和可靠性至关重要。本研究提出了一种新颖的，非侵入性的方法来经验估计蒸汽质量，使用阴影成像，结合创新的监督机器学习分割技术。这一贡献是原创的适应监督像素级分类，传统上应用于生物医学成像，两相流，代表一个跨学科的方法。该技术独特地实现了复杂蒸汽流相互作用的阈值设定，包括“不连续”环空流动。专用的实验测试设备可实现可重复的蒸汽质量测量，通过冷凝水疏水阀进行验证，标准偏差仅为0.02。Photron SA4相机在较低的规格设置下工作，以30 kg/h和1.2 - 1.4 BarA的速度通过20 mm的内部瞄准镜捕获2D图像。针对不同的组合评估了两种图像分割方法：一种是单独训练的方法，其中为每个质量（200张图像中的5张）开发单独的分类器，另一种是多条件训练的方法，其中使用来自多个质量条件的训练样本开发广义分类器（每个图像在3个质量中各2张图像）。使用斐济的监督机器学习工具，两种方法的蒸汽质量估计与冷凝水疏水阀测量结果非常吻合，在x = 0.77至x = 0.9的质量范围内，达到了+0.02至-0.04的良好精度。这些发现表明，这种独特的方法可以集成到实时流量测量中，将光学诊断与自动分割相结合，从而能够在工业限制下精确监测流量状况。

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引用次数: 0

Vaporization of acoustically levitated alcohol/water droplets in humid air 在潮湿空气中声学悬浮酒精/水滴的汽化

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-03 DOI: 10.1016/j.ijheatmasstransfer.2026.128402

Guillaume Castanet , Minghao Wang , Mehdi Stiti

The evaporation of droplets composed of water and light alcohols (ethanol, 2-propanol, and 1-propanol) is investigated using acoustically levitated droplets, combined with simultaneous measurements of droplet size and chemical composition. Droplet evolution is influenced by the relative volatility of the components, ambient humidity, and temperature. Ethanol and 2-propanol droplets consistently evolve toward pure water due to rapid alcohol evaporation and condensation of water from the surrounding air. In contrast, 1-propanol droplets can either lose most of their alcohol or retain a significant fraction, depending on the initial composition and environmental conditions. The combined experiments and modeling reveal the existence of stable final compositions under given conditions, toward which droplets naturally evolve, forming what can be described as a “composition attractor.” This attractor arises from the balance between evaporation, water absorption, and non-ideal mixture effects. Similar behavior may occur for other liquid mixtures with moderate differences in volatility. These findings provide new insight into the complex dynamics of multicomponent droplet evaporation and highlight the role of environmental conditions in determining the final composition.

利用声悬浮液滴，结合液滴大小和化学成分的同时测量，研究了由水和轻醇（乙醇、2-丙醇和1-丙醇）组成的液滴的蒸发。液滴的演化受组分的相对挥发性、环境湿度和温度的影响。由于酒精的快速蒸发和周围空气中的水的冷凝，乙醇和2-丙醇液滴不断地向纯水演变。相比之下，1-丙醇液滴要么失去大部分酒精，要么保留相当一部分，这取决于初始成分和环境条件。实验和模型的结合揭示了在给定条件下稳定的最终成分的存在，液滴自然地向其进化，形成了可以被描述为“成分吸引子”的东西。这个吸引子产生于蒸发、吸水和非理想混合效应之间的平衡。在挥发性有中等差异的其他液体混合物中也可能出现类似的行为。这些发现为多组分液滴蒸发的复杂动力学提供了新的见解，并强调了环境条件在决定最终组成中的作用。

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引用次数: 0

Thermal Management Strategies for Electronic Systems 电子系统的热管理策略

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-05 DOI: 10.1016/j.ijheatmasstransfer.2026.128463

Kambiz Vafai , Vincenzo Bianco , Kun Yang , Sainan Lu

引用次数: 0

Experimental study of macroscopic characteristics of sprays formed by impinging jets under flash-boiling conditions 闪沸条件下撞击射流形成的喷雾宏观特性的实验研究

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-02-03 DOI: 10.1016/j.ijheatmasstransfer.2026.128439

Bartosz Grzegorz Kaźmierski, Łukasz Jan Kapusta

Liquid jets impinging on each other have been widely used in rocket engines to atomise the fuel and oxidiser. In the upper rocket stages, vacuum conditions occurring before the engine ignition evoke flash-boiling effects on the injected liquids. Consequently, the character of the interactions between the two colliding liquid jets changes significantly and impacts the atomisation process.

This study examined the flash-boiling effects on symmetrical impinging water jets and resultant sprays. Two synchronised cameras were used to observe the spray simultaneously from two perpendicular directions - normal and parallel to the plane of the colliding jets.

Results showed that the impingement of continuous liquid jets occurring in the subcooled regime transitioned into a collision between atomised sprays under strong flash-boiling conditions. For the first time, it was demonstrated that the post-impingement sprays generated by the two impinging flash-atomised jets are entirely different from those formed by interacting jets from multi-nozzle injectors with diverging nozzle axes. Moreover, these sprays resembled those formed by crossing gaseous jets, indicating that despite the disintegration of the jets before reaching the impingement point, momentum was effectively exchanged between the intersecting spray clouds. The resultant spray expanded primarily in the direction perpendicular to the plane of the colliding plumes, demonstrating an increase in the relevant spray angle from approximately 12° to 40° under fully developed flash-boiling conditions. These observations imply the primary significance of flash-evaporated liquid in the interaction process of two jets under flash-boiling conditions.

相互碰撞的液体射流被广泛应用于火箭发动机，使燃料和氧化剂雾化。在火箭的上一级，发动机点火前的真空条件会对注入的液体产生闪沸效应。因此，两个碰撞液体射流之间的相互作用特性发生了显著的变化，并影响了雾化过程。本文研究了对称冲击水射流和由此产生的喷雾对闪沸的影响。两台同步相机被用来同时从两个垂直的方向——法线和平行于碰撞射流平面——观察喷射。结果表明，在强闪沸条件下，发生在过冷状态下的连续液体射流撞击转变为雾化喷雾之间的碰撞。首次证明了两种撞击式闪光雾化射流产生的撞击后射流与喷嘴轴向分散的多喷嘴射流相互作用形成的射流完全不同。此外，这些喷雾与穿过气体射流形成的喷雾相似，这表明尽管射流在到达撞击点之前解体，但在相交的喷雾云之间有效地交换了动量。由此产生的喷雾主要在垂直于碰撞羽流平面的方向上扩展，表明在充分发展的闪沸条件下，相关喷雾角度从大约12°增加到40°。这些观测结果表明，闪蒸液体在闪沸条件下两射流相互作用过程中具有重要意义。

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引用次数: 0

Study of an immersion battery thermal management system based on hydrofluoroether fluid 基于氢氟醚流体的浸没式电池热管理系统研究

IF 5.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Heat and Mass Transfer

Pub Date : 2026-06-01 Epub Date: 2026-01-24 DOI: 10.1016/j.ijheatmasstransfer.2026.128422

Yuhao Luo , Ruitian Zhou , Chuanle Zhu , Shuangfeng Wang

This study investigates an immersion battery thermal management system based on hydrofluoroether fluid, with a focus on the impact of fluid flow on battery temperature under varying flow rates and discharge conditions. Experimental results show that the optimal volumetric flow rate for horizontally and vertically placed batteries is 50 mL/min and 60 mL/min, respectively, under a 3C discharge rate. At these flow rates, the maximum battery temperatures are 39.55°C and 39.84°C, respectively, demonstrating efficient temperature control. Further increases in flow rate lead to a diminishing effect on temperature reduction, indicating the presence of a saturation effect. Additionally, the study reveals that the vertically placed battery exhibits larger temperature differences and greater temperature nonuniformity compared to the horizontally placed battery under high discharge rates. Specifically, the maximum temperature difference for the vertically placed battery reaches 4.65°C, while it is only 3.87°C for the horizontally placed one. The study also highlights the critical role of both natural and forced convection in the heat transfer process, with mixed convection showing varying effectiveness depending on the battery orientation and flow conditions. This research provides valuable theoretical insights and practical guidance for optimizing IBTMS design, ensuring safe and stable battery operation under high-power discharge conditions.

研究了一种基于氢氟醚流体的浸没式电池热管理系统，重点研究了不同流量和放电条件下流体流动对电池温度的影响。实验结果表明，在3C放电速率下，水平放置和垂直放置电池的最佳体积流量分别为50 mL/min和60 mL/min。在这些流量下，电池的最高温度分别为39.55°C和39.84°C，显示出有效的温度控制。流量的进一步增加导致温度降低的效果减弱，表明存在饱和效应。此外，研究表明，在高放电速率下，垂直放置的电池比水平放置的电池表现出更大的温差和更大的温度不均匀性。其中，垂直放置的电池最大温差为4.65℃，水平放置的电池最大温差仅为3.87℃。该研究还强调了自然对流和强制对流在传热过程中的关键作用，混合对流根据电池的方向和流动条件表现出不同的效果。本研究为优化IBTMS设计，确保电池在大功率放电条件下安全稳定运行提供了有价值的理论见解和实践指导。

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引用次数: 0