International Communications in Heat and Mass Transfer最新文献_第7页

Experimental study on the influence of sub-millimeter copper foams on boiling heat transfer in vertical orientation 亚毫米级泡沫铜对垂直方向沸腾传热影响的实验研究

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-03-01 Epub Date: 2025-12-18 DOI: 10.1016/j.icheatmasstransfer.2025.110346

Hyun Jin Yong , Jaehyeok Yang , Yun Seok Choi , Il Woong Park , Sai Raja Gopal Vadlamudi , Uwe Hampel , Hyun Sun Park

Recent years have seen porous metal foams gaining research interest for boosting boiling heat transfer in sustainable energy systems because of their high surface area, nucleation sites, and thermal conductivity. To keep electronic devices compact, surface coatings must be thin to lower thermal resistance and optimize space, with components often placed vertically. Despite extensive research, most studies have focused on millimeter foams in horizontal orientations, leaving the pool boiling behavior of sub-millimeter foams in vertical configurations largely unexplored. In this work, the pool boiling performance of vertically oriented copper foams with thicknesses of 50, 100, and 200 μm and pore densities ranging from 90 to 130 PPI is investigated. The influence of foam thickness and pore size on boiling characteristics such as onset of nucleate boiling (ONB), heat transfer coefficient (HTC), and critical heat flux (CHF) is quantitatively analyzed. All copper foam surfaces exhibit enhanced CHF compared to the bare silicon surface, while HTC trends vary depending on foam thickness and pore density. Two distinct CHF and HTC trends are observed based on foam thickness, indicating two different mechanisms at work. In one case, at 200 μm cooper foam thickness, higher wall superheats and poor HTCs are seen, suggesting vapor sublayer dryout caused by coalescence of vapor channels induced by hydrodynamic instabilities. In the other case, at 50 μm, a non-monotonic CHF trend with lower superheats is observed, similar to micro-pillared surfaces, which results from dryout of the liquid sublayer beneath vapor bubbles. These findings on CHF trends in porous metal foams highlight the unique characteristics of microporous foam structures in a vertical orientation and guide future research aimed at optimizing foam designs for improved boiling heat transfer.

近年来，多孔金属泡沫因其高表面积、高成核位置和高导热性而在可持续能源系统中获得了促进沸腾传热的研究兴趣。为了保持电子设备的紧凑性，表面涂层必须薄，以降低热阻和优化空间，组件通常垂直放置。尽管进行了广泛的研究，但大多数研究都集中在水平方向的毫米泡沫上，而对垂直配置的亚毫米泡沫的池沸腾行为知之甚少。本文研究了厚度为50、100和200 μm、孔密度为90 ~ 130 PPI的垂直取向泡沫铜的池沸性能。定量分析了泡沫厚度和孔径对成核沸腾起始时间（ONB）、传热系数（HTC）和临界热流密度（CHF）等沸腾特性的影响。与裸硅表面相比，所有铜泡沫表面都表现出增强的CHF，而HTC的趋势取决于泡沫厚度和孔隙密度。根据泡沫厚度，观察到两种不同的CHF和HTC趋势，表明两种不同的机制在起作用。当铜泡沫厚度为200 μm时，出现了较高的壁面过热度和较差的HTCs，表明水动力不稳定性引起的蒸汽通道聚并导致了蒸汽亚层干化。在另一种情况下，在50 μm处，观察到具有较低过热度的非单调CHF趋势，类似于微柱状表面，这是由蒸汽泡下的液体亚层干燥引起的。这些关于多孔金属泡沫中CHF趋势的发现突出了微孔泡沫结构在垂直方向上的独特特征，并指导了未来旨在优化泡沫设计以改善沸腾传热的研究。

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引用次数: 0

Parametric design investigation of Vortex-based sweeping jet actuator for film cooling on high-pressure turbine vane 高压涡轮叶片气膜冷却旋涡型掠流射流执行器参数化设计研究

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-03-01 Epub Date: 2025-12-19 DOI: 10.1016/j.icheatmasstransfer.2025.110328

Arshad Farooq, Shaowen Chen (陈绍文), Pengcheng Yang (杨鹏骋), Yimin Zhang (张谊民)

Film cooling is vital for the efficient operation and reliability of modern gas turbine engines. This paper investigates the aerodynamic and thermal performance of a vortex-based sweeping jet actuator (VSJA) implemented on the suction side of a high-pressure turbine stator vane, comparing a conventional sweeping jet actuator (CSJA), a parametrically optimized VSJA, and a baseline design. An unsteady RANS simulations accompanied by the k–ω SST turbulence model is used to evaluate film cooling effectiveness at blowing ratios of M = 0.52, 1.09, and 1.52. Experiments were conducted to analyze flow dynamics of both baseline and optimized VSJA configurations using surface oil flow visualization and dynamic pressure sensors to characterize unsteady jet behavior. Experiments showed that the optimized VSJA produced wider fan angles (∼100° vs. ∼70°), higher oscillation frequencies, and greater lateral jet spreading compared with the baseline configuration. URANS results further demonstrated that these characteristics strengthened coolant dispersion and wall interaction, leading to notable improvements in time-averaged adiabatic film cooling effectiveness (

\bar{η}

) At M = 1.52, the optimized VSJA provided 28.1 % and 60.3 % higher

\bar{η}

than CSJA and baseline, respectively. Time-averaged flow fields revealed more coherent anti-counter-rotating vortex pairs, enhancing coolant coverage. Aerodynamically, the optimized VSJA reduced total pressure loss to 8.00 %, compared with 10.27 % for the CSJA, achieving an improved balance between cooling effectiveness and flow efficiency, despite the baseline case yielding the lowest loss. Overall, the optimized VSJA demonstrates superior performance for advanced gas turbine cooling applications, effectively combining enhanced film cooling with reduced aerodynamic losses.

气膜冷却对于现代燃气涡轮发动机的高效运行和可靠性至关重要。本文研究了高压涡轮定子叶片吸力侧旋涡型掠流射流致动器（VSJA）的气动和热性能，并对常规掠流射流致动器（CSJA）、参数化优化的VSJA和基线设计进行了比较。采用非定常RANS模拟和k -ω SST湍流模型，对M = 0.52、1.09和1.52下的气膜冷却效果进行了评价。利用地面油流可视化和动态压力传感器，对基线和优化后的VSJA配置进行了流动动力学分析，以表征非定常射流行为。实验表明，与基线配置相比，优化后的VSJA产生了更宽的风扇角（~ 100°vs ~ 70°）、更高的振荡频率和更大的横向射流扩散。URANS结果进一步表明，这些特性增强了冷却剂的分散和壁面相互作用，导致时间平均绝热膜冷却效率（η¯）显著提高。在M = 1.52时，优化后的VSJA的η¯分别比CSJA和基线高28.1%和60.3%。时间平均流场显示出更连贯的反反向旋转涡对，增强了冷却剂的覆盖范围。在空气动力学方面，优化后的VSJA将总压损失降低至8.00%，而CSJA的总压损失为10.27%，在冷却效果和流动效率之间取得了更好的平衡，尽管基准情况下的损失最低。总体而言，优化后的VSJA在先进的燃气轮机冷却应用中表现出卓越的性能，有效地将增强的气膜冷却与减少的气动损失相结合。

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引用次数: 0

Boiling inversion induced heat transfer enhancement of copper heat-spreaders with electrodeposited dendritic-bush structures 电沉积枝状灌木结构铜散热器的沸腾转化强化传热研究

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-03-01 Epub Date: 2025-12-19 DOI: 10.1016/j.icheatmasstransfer.2025.110311

En-Chia Liu , Jie-Hau Liao , Heng-Chieh Chien , Jui-Cheng Yu , Chao-Yang Chiang , Po-Hsun He , Hsuan-Chi Weng , Ming-Ji Dai , Chien-Neng Liao

Nucleate pool boiling is highly effective for cooling high-power electronic devices and microsystems. In this work, a superhydrophilic dendritic-bush-shaped coating was electrodeposited on Cu substrates as boiling enhancement structures (BES). By varying H₂SO₄ and H₃BO₃ concentrations in the electrolyte, porous Cu films with different thicknesses and morphologies were obtained. Pool boiling experiments measured the critical heat flux (CHF) and heat transfer coefficient (HTC), while a contact angle analyzer and capillary rise tests evaluated the wettability and wicking properties. A distinct boiling inversion phenomenon was observed for porous Cu films with optimized structural parameters. High-speed imaging of bubble nucleation, growth, and departure revealed the link between surface architecture, bubble dynamics, and heat transfer performance. The optimized dendritic Cu structure achieved a CHF of 216 W/cm² and an HTC of 24.6 W/cm²K, corresponding to enhancements of 125 % and 473 % over flat Cu. These findings highlight the promise of electrodeposited dendritic-bush structures for heat dissipation enhancement through nucleate pool boiling.

核池沸腾对于大功率电子器件和微系统的冷却是非常有效的。在这项工作中，电沉积了一种超亲水性枝状灌木状涂层作为沸腾增强结构（BES）。通过改变电解液中H2SO4和H3BO3的浓度，可以得到不同厚度和形态的多孔Cu膜。池沸腾实验测量了临界热流密度（CHF）和传热系数（HTC），接触角分析仪和毛细上升测试评估了润湿性和排芯性能。优化结构参数后，多孔Cu膜出现明显的沸腾反转现象。气泡成核、生长和离开的高速成像揭示了表面结构、气泡动力学和传热性能之间的联系。优化后的枝晶Cu结构的CHF为216 W/cm2， HTC为24.6 W/cm2K，分别比平面Cu提高了125%和473%。这些发现突出了电沉积枝状灌木结构通过核池沸腾增强散热的前景。

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引用次数: 0

3D numerical study of hydrogen storage in nano-enhanced metal hydride reactor with branching type fins 分支型翅片纳米强化金属氢化物反应器储氢的三维数值研究

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-03-01 Epub Date: 2025-12-15 DOI: 10.1016/j.icheatmasstransfer.2025.110301

Fatih Selimefendigil , Gürel Şenol , Hakan F. Öztop

In this paper, 3D numerical study of hydrogen storage in a metal hydride (MH) reactor is examined by installing branching type fins and nano-enhanced MH. Titanium dioxide (TiO₂) is utilized as the nanomaterial to be used as an additive in the MH domain in terms of heat transfer enhancement during the absorption. The metal hydride used for the reactor is MgH₂ due its high volumetric and gravimetric capacity. Comparative studies are performed for the hydrogen storage system by using finite element-based solver. Number of branching fins used during the absorption is taken between 10and 50 while hydrogen supply pressure is considered between 5and 15atm. The coolant temperature is considered between 5

^{°} C

and 20

^{°} C

. Percentage weight (wt%) of absorbed hydrogen, and average MH bed temperatures are evaluated for each case and comparative results are presented. The best case is obtained with 50 branching fins, at supply pressure as 15atm and the coolant temperature as 5

^{°} C

. Using 50 fins results in reduction of sorption time by 22 % and the average bed temperature in the MH bed by 27 %. The coolant temperature at 5 °C reduces the absorption time and the average bed temperature by 34 % and 48 %, respectively, while the highest-pressure case results in a 48 % reduction in the sorption time compared to the lowest pressure case. Results are useful for the design and development of thermal management systems for hydrogen storage in MH reactors.

本文通过在金属氢化物（MH）反应器中安装分支型翅片和纳米增强MH，对氢的储氢进行了三维数值研究。利用二氧化钛（TiO2）作为纳米材料，在MH畴中作为添加剂，在吸收过程中增强传热。该反应器使用的金属氢化物是MgH2，因为它具有高的体积和重量容量。采用基于有限元的求解方法对储氢系统进行了对比研究。在吸收过程中使用的分支鳍数在10到50之间，而氢供应压力被认为在5到15atm之间。冷却液温度考虑在5℃~ 20℃之间。对每一种情况下吸收氢的重量百分比（wt%）和平均MH床温度进行了评估，并给出了比较结果。在供应压力为15atm，冷却剂温度为5°C的情况下，获得50个分支鳍的最佳情况。使用50片翅片可使吸附时间缩短22%，MH床的平均床温降低27%。冷却剂温度为5°C时，吸附时间和平均床层温度分别减少了34%和48%，而最高压力情况下的吸附时间比最低压力情况下减少了48%。研究结果对氢离子反应器储氢热管理系统的设计和开发具有指导意义。

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引用次数: 0

Closed-form solution to radial diffusion via a time-aware series approximation for the reciprocal of the Hankel-function modulus in s-domain 通过s域汉克尔函数模的倒数的时间感知序列逼近的径向扩散的封闭形式解

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-03-01 Epub Date: 2025-12-30 DOI: 10.1016/j.icheatmasstransfer.2025.110432

Zehui Sun, Zhe Qian, Lijian Wu, Qixu Chen, Qunjing Wang

The exact solution to radial diffusion in semi-infinite media under Dirichlet boundary conditions is provided as a Jaeger integral, which has long remained unsolved. The primary obstacle is the intractable integrand factor

N (s) = s^{- 1} {[J_{0}^{2} (s) + Y_{0}^{2} (s)]}^{- 1}

. This paper overcome this long-standing challenge by developing a time-aware, asymptotics-preserving series representation of

N (s)

. This representation seamlessly bridges the small- and large-

s

asymptotics of

N (s)

and maintains the approximation errors in the intermediate

s

-regime uniformly small upon transforming into the time domain. The series representation of

N (s)

enables the first-ever analytical evaluation of this Jaeger integral, yielding a closed-form approximate solution uniformly valid over the whole time domain for the radial diffusion problem. The solution is compactly presented in terms of hypergeometric functions and precisely replicates the asymptotic behaviors of the original Jaeger integral solution. As direct corollaries, this paper also derives several closed-form formulas for quantities of practical interest, such as the boundary flux, the cumulative transfer across the boundary, and the time evolution of the diffusion front. The solution and its corollaries provide a robust tool for solving inverse problems of radial diffusion under Dirichlet boundary conditions, which are prevalent in fields such as geothermal energy and hydrogeology. Moreover, the proposed time-aware, asymptotics-preserving methodology provides a distinct alternative to traditional numerical inverse Laplace transforms and complements the Laplace method workflow commonly used to reduce partial differential equations of heat and mass transfer.

给出了半无限介质中径向扩散在Dirichlet边界条件下的精确解，这是一个长期未解的Jaeger积分。主要障碍是棘手的积分因子N(s)=s−1[J02(s)+Y02(s)]−1。本文通过开发N(s)的时间感知、渐近保持级数表示克服了这一长期存在的挑战。这种表示无缝地连接了N(s)的小s和大s渐近性，并在转换到时域后保持中间s区域的近似误差一致小。N(s)的级数表示使得首次解析计算Jaeger积分成为可能，从而得到在整个时域内径向扩散问题一致有效的闭形式近似解。该解以超几何函数的形式简洁地呈现出来，并精确地复制了原Jaeger积分解的渐近行为。作为直接推论，本文还导出了一些实际量的封闭公式，如边界通量、跨边界累积转移和扩散锋的时间演化。该解及其推论为求解Dirichlet边界条件下径向扩散反问题提供了一个强大的工具，这些问题在地热能和水文地质等领域非常普遍。此外，所提出的时间感知、渐近保持方法为传统的数值拉普拉斯逆变换提供了一种独特的替代方案，并补充了通常用于减少热量和质量传递偏微分方程的拉普拉斯方法工作流。

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引用次数: 0

Vascularized networks for two-phase flow evaporative cooling. How hierarchical flow distribution reduces friction losses 两相流蒸发冷却的血管化网络。分级流分布如何减少摩擦损失

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-03-01 Epub Date: 2025-12-31 DOI: 10.1016/j.icheatmasstransfer.2025.110438

Sylvie Lorente

Data centers require thermal solutions allowing to dissipate always higher heat loads with minimal pumping power. This work presents a methodology to design vascularized hierarchical flow networks for two-phase evaporative cooling, searching for minimum friction losses in flow distribution and collection networks. Two network configurations are considered: a ladder configuration, in which inlet and outlet channels are located on the same side, and a canopy-to-canopy configuration, with inlet and outlet on opposite sides of the network. The theoretical framework developed allows to determine optimal diameter ratios along hierarchical branches under constant refrigerant volume. The results demonstrate that a hierarchical diameter distribution reduces significantly the total pressure losses compared to single-diameter networks. In addition, we show that the reduction in friction losses depends strongly on the vapor quality, with the maximum improvement obtained between 0.50 and 0.60. Finally, the canopy-to-canopy network achieves the lowest overall friction losses and exhibits less sensitivity to the thermodynamic quality, making it the most efficient architecture for two-phase evaporative cooling applications.

数据中心需要热解决方案，以最小的泵送功率消散始终较高的热负荷。这项工作提出了一种方法来设计两相蒸发冷却的血管化分层流动网络，在流动分配和收集网络中寻找最小的摩擦损失。考虑了两种网络配置：一种是梯子配置，其中入口和出口通道位于同一侧；另一种是天篷对天篷配置，入口和出口位于网络的两侧。所开发的理论框架允许确定在恒定制冷剂体积下沿分层分支的最佳直径比。结果表明，与单直径网络相比，分层直径分布显著降低了总压损失。此外，我们表明摩擦损失的减少在很大程度上取决于蒸汽质量，在0.50和0.60之间获得最大的改善。最后，冠层到冠层的网络实现了最低的整体摩擦损失，对热力学质量的敏感性较低，使其成为两相蒸发冷却应用中最有效的结构。

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引用次数: 0

Heat transfer and flow dynamics of power-law fluids in a lid-driven cavity with a flexible flow modulator 带柔性流量调节器的盖驱动腔内幂律流体的传热与流动动力学

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-03-01 Epub Date: 2025-12-29 DOI: 10.1016/j.icheatmasstransfer.2025.110389

Fahim Tanfeez Mahmood, Mohammad Nasim Hasan

This research computationally investigates heat transfer characteristics within a lid-driven square cavity containing non-Newtonian Power-law fluids. An adiabatic flexible flow modulator, fastened centrally on the heated bottom wall, deforms dynamically under hydrodynamic forces. The coupled fluid-structure interaction (FSI) is solved using an Arbitrary Lagrangian-Eulerian (ALE) formulation, while the Galerkin finite element approach resolves the coupled mass, momentum, energy, and structural equations. The system's hydrodynamics is represented by the alteration of the power-law index (0.6 ≤ n ≤ 1.4), Richardson number (0.1 ≤ Ri ≤ 10.0), and Prandtl number (1 ≤ Pr ≤ 50), whereas the structural response is governed by the Cauchy number (10⁻⁷ ≤ Ca ≤ 10⁻⁴). The outcomes are analyzed through the assessment of streamlines and isotherm distribution, spatially and time-averaged Nusselt number variations, modulator tip deflection, and Power Spectrum Analysis. Findings unravel that the system's thermal efficacy is significantly influenced by the fluid rheology (n), convection regime (Ri), and momentum diffusivity (Pr), while the modulator's elasticity (Ca) has minimal effect. At stronger hydrodynamic conditions (Ri = 10 and Pr = 10), the flow modulator exhibits periodic fluttering, which ceases upon its rigidification. Under optimal thermal conditions (n = 0.6, Ri = 10, Pr = 50, and Ca = 10⁻⁴), the heat transfer enhancement reaches 77 %, with a peak time-averaged Nusselt number of Nu_avg = 62.8. Shear-thinning fluids consistently outperform Newtonian and shear-thickening fluids in absolute heat transfer, whereas shear-thickening fluids offer maximum thermal enhancement (up to 12.38 %) when modulation effects are compared. These insights can be instrumental to augment heat removal in systems processing non-Newtonian fluids, including chemical heat exchangers, food-processing equipment, and wastewater treatment plants, employing deformable inserts.

本研究计算研究了包含非牛顿幂律流体的盖驱动方形腔内的传热特性。一个绝热柔性流量调节器，固定在加热的底壁上，在水动力作用下动态变形。耦合流固耦合（FSI）采用任意拉格朗日-欧拉（ALE）公式求解，而伽辽金有限元方法求解耦合的质量、动量、能量和结构方程。系统的流体力学由幂律指数（0.6≤n≤1.4）、理查德森数（0.1≤Ri≤10.0）和普朗特数（1≤Pr≤50）的变化来表示，而结构响应则由柯西数（10−7≤Ca≤10−4）来控制。通过流线和等温线分布、空间和时间平均努塞尔数变化、调制器尖端偏转和功率谱分析来分析结果。研究结果表明，系统的热效率受流体流变学(n)、对流状态（Ri）和动量扩散率（Pr）的显著影响，而调制器的弹性（Ca）的影响最小。在较强的水动力条件下（Ri = 10和Pr = 10），流量调节器表现出周期性的颤振，并在其硬化后停止颤振。在最优热条件（n = 0.6, Ri = 10, Pr = 50, Ca = 10−4）下，材料的换热强化达到77%，峰值时间平均努塞尔数Nuavg = 62.8。剪切减薄流体在绝对传热方面始终优于牛顿流体和剪切增稠流体，而剪切增稠流体在调制效应比较时提供最大的热增强（高达12.38%）。这些见解可以帮助增加非牛顿流体处理系统的热量去除，包括化学热交换器，食品加工设备和废水处理厂，采用可变形插入。

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引用次数: 0

Hydrothermal performance and entropy production rate in distilled H2O flowing in a converging corrugated pipe with increasing corrugation parameters 随着波纹参数的增大，蒸馏水在波纹管中的水热性能和熵产率

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-03-01 Epub Date: 2026-01-07 DOI: 10.1016/j.icheatmasstransfer.2025.110457

Olatomide Gbenga Fadodun , Odunayo Olawuyi Fadodun , Amr Kaood

<div><div>This study examined the turbulent hydrothermal performance of distilled H<sub>2</sub>O flow in converging corrugated pipes (CCPs), whose corrugation parameters (amplitude and width of the corrugation) vary along the direction of flow from the first and second thermodynamic perspectives. The Reynolds average Navier-Stokes turbulence model <span><math><mfenced><mrow><mi>SST</mi><mspace></mspace><mi>k</mi><mo>−</mo><mi>ω</mi></mrow></mfenced></math></span> was used to simulate the flow inside the pipe. The influences of the Reynolds number <span><math><mfenced><mrow><mn>5</mn><mo>×</mo><msup><mn>10</mn><mn>3</mn></msup><mo>≤</mo><mi>Re</mi><mo>≤</mo><mn>2.5</mn><mo>×</mo><msup><mn>10</mn><mn>4</mn></msup></mrow></mfenced></math></span>, diameter ratio <span><math><mfenced><mrow><mn>1</mn><mo>≤</mo><mi>DR</mi><mo>≤</mo><mn>1.5</mn></mrow></mfenced></math></span>, amplitude ratio <span><math><mfenced><mrow><mn>1</mn><mo>≤</mo><msup><mi>GR</mi><mi>e</mi></msup><mo>≤</mo><mn>1.07</mn></mrow></mfenced></math></span>, and width ratio <span><math><mfenced><mrow><mn>1</mn><mo>≤</mo><msup><mi>GR</mi><mi>w</mi></msup><mo>≤</mo><mn>1.07</mn></mrow></mfenced></math></span> on the average Nusselt number <span><math><mfenced><mi>Nu</mi></mfenced></math></span>, Poiseuille number (<em>f Re</em>), performance evaluation criterion (<em>PEC</em>), and the average volumetry entropy production rate <span><math><mfenced><msub><mi>S</mi><mi>gen</mi></msub></mfenced></math></span>were thoroughly examined. The findings revealed that <em>Nu</em>, <em>f Re</em>, <em>PEC</em>, and <span><math><mfenced><msub><mi>S</mi><mi>gen</mi></msub></mfenced></math></span> are more sensitive to <span><math><msup><mi>GR</mi><mi>e</mi></msup></math></span> and DR than are <span><math><msup><mi>GR</mi><mi>w</mi></msup></math></span>. For example, at <span><math><mi>Re</mi><mo>=</mo><mn>2.0</mn><mo>×</mo><msup><mn>10</mn><mn>4</mn></msup></math></span>, <span><math><msup><mi>GR</mi><mi>w</mi></msup><mo>=</mo><mn>1</mn></math></span> and <span><math><mi>DR</mi><mo>=</mo><mn>1</mn></math></span>, the values of <em>Nu</em>, <em>f Re</em>, <em>PEC</em>, and <span><math><mfenced><msub><mi>S</mi><mi>gen</mi></msub></mfenced></math></span> across the range of <span><math><msup><mi>GR</mi><mi>e</mi></msup></math></span> are considered to change by a factor of <span><math><mfenced><mn>1.17</mn><mn>2.16</mn><mn>0.91</mn><mrow><mtext>and</mtext><mspace></mspace><mn>0.82</mn></mrow></mfenced></math></span>. The corresponding values across the range of <span><math><msup><mi>GR</mi><mi>w</mi></msup></math></span> considered are <span><math><mfenced><mn>0.911</mn><mn>0.929</mn><mn>0.933</mn><mrow><mtext>and</mtext><mspace></mspace><mn>1.11</mn></mrow></mfenced></math></span>. For<span><math><mspace></mspace><mi>Re</mi><mo>=</mo><mn>2.0</mn><mo>×</mo><msup><mn>10</mn><mn>4</mn></msup></math></span>, <span><math><msup><mi>GR</mi><mi>w</mi></msup><mo>=</mo><mn>1</mn></math></span> & <span><math><

本文从第一和第二热力学角度考察了波纹管中波纹参数（波纹振幅和波纹宽度）沿流动方向变化的蒸馏水湍流热液性能。采用Reynolds平均Navier-Stokes湍流模型SSTk−ω模拟管内流动。考察了雷诺数5×103≤Re≤2.5×104、直径比1≤DR≤1.5、幅值比1≤GRe≤1.07、宽比1≤GRw≤1.07对平均努塞尔数Nu、普塞耶数（f Re）、性能评价标准（PEC）和平均体积熵产率sgen2的影响。结果显示Nu、fre、PEC和Sgen对GRe和DR的敏感性高于GRw。例如，在Re=2.0×104, GRw=1， DR=1时，认为在GRe范围内Nu， f Re， PEC， Sgen的值以1.172.160.91和0.82的因子变化。在考虑的GRw范围内对应的值为0.9110.9290.933和1.11。对于re =2.0×104, GRw=1 & GRe=1，考虑的DR范围内对应的值为{1.15,7.11,0.601,0.834}。此外，研究还表明，DR的降低会增加PEC值，例如，当DR = 1、1.25和1.50时，波纹参数分别为1.091、0.812和0.656的ccp的PEC值。此外，基于响应面法（RSM）建立了Nu、PEC、fRe和Sgen之间新的相关性。最后，通过多目标优化技术（MOOT）对Nu、fre和PEC同时进行优化。优化结果（Pareto front）表明，Nu和fRe同时达到最优值，而PEC在低Nu和fRe值时达到最大值。因此，所提出的设计通过改善传热和最小化压降损失，提供了显著的节能潜力，使其适用于紧凑型热交换器，催化反应器，电子冷却系统和其他相关应用。

引用次数: 0

Multi-objective optimization design and sensitivity analysis of proton exchange membrane fuel cell flow channel under assembly force 装配力作用下质子交换膜燃料电池流道的多目标优化设计及灵敏度分析

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-03-01 Epub Date: 2026-01-07 DOI: 10.1016/j.icheatmasstransfer.2026.110490

Xiuxiu Sun, Weituo Feng, Qian Zhang, Guoxi Jing, Teng Ma

The optimal design of flow channel can enhance proton exchange membrane fuel cell (PEMFC) operational efficiency by improving reactant distribution and mass transfer characteristics. This study adopted channel width, height, rib width, and turning angle as optimization variables, targeting enhanced power density, reduced channel pressure drop, and improved PEMFC current density distribution uniformity. The optimum solution set for the flow field structure emerged from integrating Latin hypercube sampling, artificial neural networks, and multi-objective gray wolf algorithm. The flow field's optimal configuration was determined by calculating the PEMFC's composite score via the entropy weight method, with validation through numerical simulation and experimentation. The results demonstrated that optimal PEMFC performance was achieved under the geometric configuration of 1.1 mm channel width, 1.2 mm channel height, 0.6 mm rib width, and 50 % turning angle. The experimental data shows that the optimized performance at 0.95 A cm⁻² revealed a 4.51 % power density increase, with channel pressure drop and PEMFC current density uniformity index declining by 37.91 % and 23.43 % respectively. Furthermore, the optimized flow channel significantly enhances heat and mass transfer, leading to improved temperature uniformity and reactant distribution, which collectively contribute to the overall performance enhancement of the PEMFC.

流动通道的优化设计可以通过改善反应物分布和传质特性来提高质子交换膜燃料电池（PEMFC）的运行效率。本研究以通道宽度、高度、肋宽、转弯角度为优化变量，以提高功率密度、减小通道压降、改善PEMFC电流密度分布均匀性为目标。将拉丁超立方采样、人工神经网络和多目标灰狼算法相结合，得到了流场结构的最优解集。通过熵权法计算PEMFC的综合得分，确定流场的最优构型，并通过数值模拟和实验验证。结果表明，在通道宽度为1.1 mm、通道高度为1.2 mm、肋宽为0.6 mm、转角为50%的几何构型下，PEMFC的性能最优。实验数据表明，优化后的PEMFC在0.95 A cm−2下的功率密度提高了4.51%，通道压降和电流密度均匀性指数分别下降了37.91%和23.43%。此外，优化后的流道显著增强了传热传质，从而改善了温度均匀性和反应物分布，这些都有助于提高PEMFC的整体性能。

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引用次数: 0

Performance analysis of a novel inclined baffle heat exchanger with drainage plates for high efficiency and low resistance 新型高效低阻斜折流板换热器性能分析

IF 6.4 2区工程技术 Q1 MECHANICS

International Communications in Heat and Mass Transfer

Pub Date : 2026-03-01 Epub Date: 2026-01-31 DOI: 10.1016/j.icheatmasstransfer.2026.110636

Zilong Wang , Yongfa Yang , Yang Fu , Xiubai Hu , Cong Dong , Chenyu Zhu

To resolve the thermal-hydraulic trade-off in conventional baffle exchangers, an efficient low-resistance inclined baffle heat exchanger (IBHE) is proposed by integrating a drainage plate and an overflow orifice. Three configurations: an inclined baffle heat exchanger with drainage plates (DPX-IBHE), an inclined baffle heat exchanger without drainage plates (NDP-IBHE), and a reference segmental baffle heat exchanger (SGHE), were simulated using 3D CFD methodology. A structural flow field analysis method was employed to evaluate and compare the thermal-hydraulic performance of the heat exchanger with and without the drainage plates. The drainage influence factor (DIF) and energy economic coefficient (EEC) metrics were introduced to evaluate flow and heat transfer mechanisms through temperature, pressure, and flow field analyses. Results indicate that drainage plates amplify both secondary vortices and tube bundle scouring. With average and peak DIF gains of 97.59% and 138.97%, the 10 mm plate (DP10-IBHE) outperformed other DPX-IBHE designs, reaching a maximum DIF of 2.37. The synergistic interaction among the inclined baffle, drainage plate, and overflow orifice eliminated dead zones and induced secondary vortices, increasing average shell-side velocity by 53.94% and 49.46% versus NDP-IBHE and SGHE. With 36.5% lower pressure drop and 55.35% higher (ρ·h_o·η_N)/(∆P·G_o) versus SGHE, DP10-IBHE demonstrates how drainage plates balance heat transfer and pressure drop. The positive flow design outperformed the reverse in EEC by 6.42% to 9.50% under identical flow conditions. The DP10-IBHE offers an efficient, low-resistance solution for applications like waste heat recovery, outperforming conventional segmental baffle designs in energy and economic metrics.

为了解决传统折流板换热器的热-液平衡问题，提出了一种高效的低阻力斜折流板换热器（IBHE），该换热器将排水板和溢流孔集成在一起。采用三维CFD方法，对带排水板的倾斜折流板换热器（dx - ibhe）、不带排水板的倾斜折流板换热器（NDP-IBHE）和参考节段折流板换热器（SGHE）三种配置进行了数值模拟。采用结构流场分析方法对带排水板和不带排水板换热器的热工性能进行了评价和比较。引入排水影响因子（DIF）和能量经济系数（EEC）指标，通过温度、压力和流场分析来评价流动和换热机制。结果表明，排水板对二次涡和管束冲刷均有增强作用。10 mm板（DP10-IBHE）的平均DIF增益为97.59%，峰值DIF增益为138.97%，优于其他dx - ibhe设计，最大DIF为2.37。倾斜挡板、排水板和溢流孔之间的协同作用消除了死区，诱导了二次涡，平均壳侧速度比NDP-IBHE和SGHE分别提高了53.94%和49.46%。与SGHE相比，DP10-IBHE的压降降低了36.5%,ρ·ho·ηN /（∆P·Go）提高了55.35%，DP10-IBHE展示了排水板如何平衡传热和压降。在相同的流量条件下，正流设计比反流设计在EEC中的性能好6.42% ~ 9.50%。DP10-IBHE为废热回收等应用提供了高效、低阻力的解决方案，在能源和经济指标方面优于传统的分段式挡板设计。

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引用次数: 0