International Journal of Thermal Sciences最新文献_第7页

Thermal effectiveness and entropy-exergy estimation in a tube with punched double V-winglets 双v形小翼冲孔管的热效率和熵耗估算

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-01-08 DOI: 10.1016/j.ijthermalsci.2026.110668

Nuthvipa Jayranaiwachira , Somchai Sripattanapipat , Pongjet Promvonge , Mahdi Erfanian Nakhchi , Sompol Skullong

Vortex generators are effective devices for enhancing heat transfer rates in heating or cooling systems with minimal frictional losses via the production of streamwise vortices. This research effort presents the perforated double V-winglet (P-DVW) and looks at how it affects heat transmission and friction when mounted inside a heat exchange tube that is consistently heated for producing multiple vortices whereas its flow is turbulent. Optimizing thermal performance for increased energy savings and maximizing the Nusselt number (Nu) to minimize heat exchanger size are the major goals. Thermal characteristics, including generated entropy and exergy efficiency, are explored in depth. A Reynolds number (Re) that varies from 4760 to 29,270 is employed to explore the friction and thermal features of the tube. The P-DVW parameters encompass attack angles of α₂ = 15° and α₁ = 30°, four porosity ratios (A_h/A_w = 0, 0.0188, 0.0523, and 0.1026), and three pitch ratios, P_R, (0.75, 1, and 1.25), while maintaining a constant winglet height. At P_R = 0.75 and A_h/A_w = 0, the P-DVW exhibits peak f and Nu values around 23.83 and 5.31 times bigger than those of the plain tube, accordingly. Further, under the specified conditions, it yields minimal entropy production, while the optimal exergy efficiency is roughly 0.9829. The thermal effectiveness of P-DVW is anticipated to reach its maximum at 2.55 with Nu_R = 4.54 at A_h/A_w = 0.0523 and P_R = 0.75 to reveal its actual benefits. Furthermore, the correlations of f, Nu, and TEF were determined for the examined range of values.

涡旋发生器是一种有效的装置，通过产生流向涡旋，在加热或冷却系统中以最小的摩擦损失提高传热率。本研究展示了穿孔双v型小翼（P-DVW），并研究了当安装在热交换管内时，它是如何影响传热和摩擦的，热交换管持续加热以产生多个涡流，而其流动是湍流的。优化热性能以增加节能和最大化努塞尔数（Nu）以最小化热交换器尺寸是主要目标。热特性，包括产生的熵和火用效率，深入探讨。雷诺数（Re）从4760到29,270不等，用于研究管的摩擦和热特性。在保持小翼高度不变的情况下，P-DVW参数包括攻角α2 = 15°和α1 = 30°，孔隙比Ah/Aw = 0、0.0188、0.0523和0.1026，节距比PR分别为0.75、1和1.25。在PR = 0.75和Ah/Aw = 0时，P-DVW的峰f和Nu值分别是普通管的23.83倍和5.31倍左右。在一定条件下，熵产最小，最优火用效率约为0.9829。在Ah/Aw = 0.0523, PR = 0.75时，P-DVW的热效率预计在2.55时达到最大值，NuR = 4.54，以显示其实际效益。此外，f， Nu和TEF的相关性被确定为所检查的值范围。

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引用次数: 0

A simplified null-point method for high resolution contact temperature measurement by means of micro-thermocouples in vacuum conditions 真空条件下微热电偶高分辨率接触测温的简化零点法

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-01-08 DOI: 10.1016/j.ijthermalsci.2026.110667

L. Thiery, J.Y. Rauch, S. Euphrasie, B. Cretin

We report on the possibility to measure the temperature of micro-devices by means of a micro-thermocouple in active mode with a simplified procedure of null-point method. Contrary to other reported procedures, there is no need of multiple scans at different distances to the sample surface. A single out of contact power calibration is required prior to the contact-point measurements. For them, only two successive measurements at different Joule heating powers of the thermocouple are necessary to deduce the actual surface temperature. We only used a low frequency voltage generator and high precision voltmeters without specific electronics except a low-pass RC filter. The reliability of the method is demonstrated with a platinum wire as a calibration tool.

本文报道了利用微热电偶在有源模式下用简化的零点法测量微器件温度的可能性。与其他报道的方法相反，不需要在不同距离的样品表面进行多次扫描。在接触点测量之前，需要进行一次非接触功率校准。对他们来说，只需要在热电偶的不同焦耳加热功率下连续两次测量就可以推断出实际的表面温度。我们只使用了一个低频电压发生器和高精度电压表，没有特定的电子设备，除了一个低通RC滤波器。用铂丝作为标定工具，验证了该方法的可靠性。

引用次数: 0

Experimental investigation on HFE-7100 flow boiling in aluminum open microchannels heat sink HFE-7100在铝开口微通道散热器内流动沸腾的实验研究

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-01-08 DOI: 10.1016/j.ijthermalsci.2026.110672

Liaofei Yin , Tianjun Qin , Wenhao Ma , Yi Ding , Yawei Xu

For thermal management of large heat-generating devices, aluminum heat sinks exhibit promising application prospects owing to their lightweight and corrosion-resistant properties. This research presents an experimental study of HFE-7100 flow boiling within an aluminum heat sink with large heating area featuring open microchannels. By incorporating visualizations of bubble dynamics and flow regime transitions, the heat transfer mechanisms in large-area open microchannels heat sink were elucidated. The study revealed that increasing the mass flux simultaneously enhanced both the average heat transfer coefficient (HTC) and the critical heat flux (CHF), while elevated inlet temperatures significantly improved heat removal capability under moderate to high heat flux conditions. Notably, a previously unreported two-phase flow regime was identified, characterized by wave-like periodic features, and was termed “surge flow”. The flow boiling regime underwent longitudinally a sequential evolution from bubbly flow to plug flow and finally to surge flow along the flow direction. Examining the localized thermal performance across various regions of the heat sink revealed that the HTC of the surge flow regime exceeded those of bubbly and plug flow patterns by as much as 117.1 % and 58.7 %, respectively. Furthermore, the CHF was observed when the surge flow occupied approximately 65.0 %–70.0 % of the flow passage in the heat sink.

在大型发热设备的热管理中，铝制散热片具有轻质、耐腐蚀的特点，具有广阔的应用前景。本研究对HFE-7100在具有开放微通道的大加热面积铝散热器内流动沸腾进行了实验研究。结合气泡动力学和流态转变的可视化，阐明了大面积开口微通道散热器的传热机理。研究表明，提高质量通量可以同时提高平均换热系数（HTC）和临界热流密度（CHF），而提高进口温度可以显著提高中高热流密度条件下的换热能力。值得注意的是，研究人员发现了一种以前未报道过的两相流，其特征是波浪状的周期性特征，并被称为“喘振流”。沿流动方向，流动沸腾型经历了从气泡流到塞流再到涌浪流的纵向顺序演化。通过对散热器各区域局部热性能的研究表明，浪涌流模式的HTC分别比气泡流模式和塞流模式高117.1%和58.7%。此外，当喘振流约占散热器流道的65.0% ~ 70.0%时，可以观察到CHF。

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引用次数: 0

Numerical investigation on heat transfer and flow characteristics of triply periodic minimal surface in transpiration cooling 蒸腾冷却中三周期极小面传热与流动特性的数值研究

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-01-08 DOI: 10.1016/j.ijthermalsci.2026.110666

Zeyu Zhang , Yong Song , Zhi Tao , Liming Song , Jun Li

Transpiration cooling has been proved to act as the next generation cooling technology. The Triply Periodic Minimal Surface (TPMS) structures are the newly developed porous medium with superior mechanical and thermal properties. However, an in-depth understanding of the TPMS applied in the transpiration cooling remains insufficient. In this work, a numerical investigation is established to extract the detailed information of the aerodynamic and thermal mechanisms. Four commonly used TPMS structures, P, W, G and D are compared comprehensively in terms of cooling efficiency, temperature uniformity and pressure cost. The effect of blowing ratios ranging from 0.45 % to 3.3 % and solid porosities from 0.3 to 0.5 on different structures is also investigated. The result turns out that the average cooling efficiency increases monotonously from around 0.43 to 0.96 with blowing ratio with a gradually slowing rate. The cooling behavior usually improves with decreased porosity because of better protection of coolant film. The integrated cooling performance combined with pressure cost is also discussed and found to get good grades with high blowing ratio and porosity. The structure G and D achieves superior cooling performance because of the continuous protective film attachment and highly distorted inner surface. The P structure ensures excellent temperature uniformity attributes to the minimum heat conduction resistance and velocity uniformity. But the intense vortex derived from fluid expansion and contraction causes high pressure cost and dissipation. By integrating these results, this study reveals the underlying thermofluidic mechanisms and establishes performance trends that can inform the preliminary selection of different structures.

蒸腾冷却已被证明是下一代冷却技术。三周期最小表面（TPMS）结构是近年来发展起来的具有优异力学性能和热性能的多孔介质。然而，对TPMS在蒸腾冷却中的应用还缺乏深入的了解。在这项工作中，建立了一个数值研究，以提取空气动力和热机制的详细信息。从冷却效率、温度均匀性和压力成本等方面对P、W、G、D四种常用TPMS结构进行了综合比较。研究了吹气率为0.45% ~ 3.3%，固体孔隙率为0.3 ~ 0.5对不同结构的影响。结果表明：随着吹气比的增加，平均冷却效率从0.43左右单调增加到0.96，且速度逐渐减慢；由于冷却液膜得到更好的保护，孔隙率越低，冷却性能越好。并结合压力成本对综合冷却性能进行了讨论，发现高吹风比、高气孔率可以获得良好的性能。结构G和D由于连续的保护膜附着和高度变形的内表面而具有优越的冷却性能。P结构确保了优异的温度均匀性，这归功于最小的导热电阻和速度均匀性。但由于流体膨胀和收缩而产生的强烈涡流造成了很高的压力代价和耗散。通过整合这些结果，本研究揭示了潜在的热流体机制，并建立了性能趋势，可以为不同结构的初步选择提供信息。

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引用次数: 0

A nongray-wall Weighted-Sum-of-Gray-Gases method based on Full-Spectrum Correlated-K distribution for aero-engine combustors and afterburners 基于全谱相关k分布的航空发动机燃烧室和加力燃烧室非灰壁加权和方法

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-01-07 DOI: 10.1016/j.ijthermalsci.2026.110661

Jinyu Zhu, Yuying Liu, Guanghai Liu

Thermal radiation greatly affects the performance of combustors and afterburners of aero-engines, thus, it is needed to predict the radiative heat transfer accurately and efficiently. In order to accommodate the nongray radiative property of the wall and the wide variation of pressure in combustors and afterburners, a nongray-wall WSGG with pressure varying continuously from sub-atmospheric to super-atmospheric conditions (ngWSGG-P) is proposed based on the Full-Spectrum Correlated-K distribution (FSCK), which can be employed to arbitrary wall materials and CO₂-H₂O mixtures with a temperature of 300 K–2800 K, a pressure of 0.4 atm–50 atm, and a mole fraction ratio of H₂O to CO₂ of 0.05–4.0. Two 1D flames with different pressures and length scales, and two 3D swirling and bluff-body flames with various pressures are simulated to evaluate the accuracy and efficiency of ngWSGG-P. The results show that ngWSGG-P demonstrates pretty good accuracy as compared to the benchmarks Line-By-Line and Narrow-Band Correlated-K methods, and its accuracy is close to 32-Points FSCK and better than other 3 typical WSGG methods. The computational time of ngWSGG-P is 13.7 % of that of FSCK, and close to other WSGG methods due to approximately the same number of gray gases.

热辐射对航空发动机燃烧室和加力燃烧室的性能影响很大，因此需要对其辐射传热进行准确、高效的预测。为了适应壁面非灰辐射特性和燃烧室和加力燃烧室压力变化大的特点，基于全谱相关K分布（FSCK），提出了一种压力从亚大气到超大气连续变化的非灰壁面WSGG (ngWSGG-P)，可用于温度为300 K ~ 2800 K、压力为0.4 atm ~ 50 atm的任意壁面材料和CO2-H2O混合物。H2O与CO2的摩尔分数比为0.05-4.0。模拟了两种不同压力和长度尺度的一维火焰，以及两种不同压力的三维旋流和崖体火焰，以评估ngWSGG-P的精度和效率。结果表明，与基准的Line-By-Line和窄带相关k方法相比，ngWSGG-P具有较好的精度，其精度接近32点FSCK，优于其他3种典型的WSGG方法。ngWSGG-P的计算时间是FSCK的13.7%，由于灰气体数量大致相同，与其他WSGG方法接近。

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引用次数: 0

Oscillation characteristics of cooling system with macro- and microchannel evaporators 大、微通道蒸发器冷却系统振荡特性研究

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-01-05 DOI: 10.1016/j.ijthermalsci.2026.110662

Qi Jin , Fang Wang , Jia-yi Zheng , Si-yu Liu

This study investigated the dynamics of a pumped liquid cycle system, highlighting the impact of integrating a microchannel evaporator alongside macro-channel components. Without a microchannel evaporator in the system, the pressure drop in the macro-channel evaporator exhibit some variation but remain relatively stable. However, the integration of microchannels induces periodic oscillations in mass flow rate and pressure drops even without active heating. Detailed investigations under various operating conditions reveal the oscillation characteristics. Decreasing pump speed results in reduced amplitude of mass flow rate oscillations, while their frequency increases, indicating more rapid variations. For instance, when

Q_{macro}

= 150 W,

Q_{micro}

= 0 W, as the speed decreases from 450 rpm to 250 rpm, the oscillation amplitude of wall temperature decreases from 1.51 °C to 1.39 °C and the frequency increases from 0.33 Hz to 0.44 Hz. The frequency of macro-channel pressure drop oscillations increases at lower pump speeds. Similar trends are observed in microchannel pressure drop oscillations, with amplitude tending to decrease as pump speed decreases and higher pump speeds resulting in larger amplitudes. This study highlights the system's sensitivity to the existence of the microchannel evaporator. These findings provide valuable insights for the optimization and control of pumped liquid cycle, contributing to enhanced performance and efficiency.

本研究调查了泵送液体循环系统的动力学，强调了将微通道蒸发器与宏通道组件集成在一起的影响。当系统中没有微通道蒸发器时，大通道蒸发器的压降会发生一定的变化，但保持相对稳定。然而，即使没有主动加热，微通道的集成也会引起质量流量和压降的周期性振荡。在各种工作条件下的详细研究揭示了振荡特性。泵转速降低，质量流量振荡幅度减小，频率增加，变化速度加快。例如，当Qmacro = 150 W, Qmicro = 0 W时，随着转速从450转/分降低到250转/分，壁面温度的振荡幅度从1.51°C减小到1.39°C，频率从0.33 Hz增加到0.44 Hz。泵转速越低，宏观通道压降振荡频率越高。在微通道压降振荡中也观察到类似的趋势，随着泵速的降低，振幅趋于减小，泵速越高，振幅越大。该研究突出了系统对微通道蒸发器存在的敏感性。这些发现为泵送液循环的优化和控制提供了有价值的见解，有助于提高性能和效率。

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引用次数: 0

Establishment of thermo-elastic-fluid coupling model of with considering structural thermal expansion and lubricating performances study of air foil thrust bearing 建立了考虑结构热膨胀的空气箔型推力轴承热弹流耦合模型及润滑性能研究

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-01-05 DOI: 10.1016/j.ijthermalsci.2025.110633

Shuang-min Li, Yang Wu, Cong-peng Shao, Qi An

This paper investigates air foil thrust bearings of circumferentially distributed bumps, employing non-isothermal Reynolds equation and 3D energy equation to describe the pressure distribution, thickness distribution, and temperature distribution of the air film, respectively. A 3D thermo-elastic-fluid coupling model of AFTBs is established using elasticity theory and the finite element method. This model comprehensively accounts for thermal expansion of the foil structures and thrust disc, centrifugal deformation of the rotor-thrust disc, heat transfer between bearing structures, and thermal resistance of the air gap in the contact areas. The reliability of the theoretical model is verified by comparing numerical results with experimental results. Furthermore, the results predicted in this paper are consistent with those obtained from existing THD models in the literature. The results indicate that the TEHD model is more precise than THD model when the initial clearance decreases and rotational speed increases. On this basis, a specific example is studied and obtains the air film pressure, air film thickness, air film temperature distributions, and deformation and temperature distribution of structures considering structural thermal expansion. The two TEHD models that considers structural thermal expansion and ignores structural thermal expansion are compared by analyzing the effects of rotational speed and load on the lubricating performances of the bearing. Finally, the influences of foils structural parameters on the load capacity and the maximum temperature of all structures are also investigated to provide practical engineering reference value for bearing design.

采用非等温雷诺方程和三维能量方程分别描述气膜的压力分布、厚度分布和温度分布，研究了周向分布凸起的空气箔型止推轴承。利用弹性力学理论和有限元方法，建立了AFTBs的三维热弹流耦合模型。该模型综合考虑了箔片结构与推力盘的热膨胀、转子-推力盘的离心变形、轴承结构之间的传热以及接触区域气隙的热阻。通过与实验结果的比较，验证了理论模型的可靠性。此外，本文的预测结果与文献中已有的THD模型的预测结果一致。结果表明，当初始间隙减小、转速增大时，TEHD模型比THD模型精度更高。在此基础上，通过具体算例进行了研究，得到了考虑结构热膨胀的结构的气膜压力、气膜厚度、气膜温度分布和变形温度分布。通过分析转速和载荷对轴承润滑性能的影响，比较了考虑结构热膨胀和忽略结构热膨胀的两种TEHD模型。最后，研究了箔片结构参数对各结构承载能力和最高温度的影响，为轴承设计提供了实际的工程参考价值。

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引用次数: 0

High-efficiency heat sink design via SLM-processed diamond TPMS CuCrZr alloy: Optimizing thermal-fluid performance through volume fraction control 采用slm加工的金刚石TPMS CuCrZr合金设计高效散热器：通过体积分数控制优化热流体性能

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-01-05 DOI: 10.1016/j.ijthermalsci.2026.110657

Yaoxian Zhang , Yaqin Yang , Xueli Chen , Bin Liu , Xiaoqing Yang , Yuan Gao , Zhuoran Zhang , Delin Kong , Donghua Lei , Zezhou Kuai , Zhonghua Li , Rui Wang

The thermal management of next-generation electronic and aerospace devices demands advanced heat dissipation solutions. While fin-type heat sinks enhance thermal conduction through extended surface areas, their performance is becoming inadequate for modern applications. Triply Periodic Minimal Surface (TPMS) structures, particularly the Diamond topology, offer superior heat transfer capabilities due to their high specific surface area and permeability. However, existing studies predominantly focus on aluminum alloys or titanium alloys, with limited research on copper-based TPMS structures. Here, we investigate Selective Laser Melting (SLM)-fabricated CuCrZr Diamond structures, a promising material for aerospace thermal management due to its exceptional thermal/mechanical properties. Through numerical simulations and experimental validation, we analyze the effects of pore size and convective area on thermal performance, benchmarking against conventional fin structures. Results demonstrate that increasing relative density enhances convective heat transfer but elevates pressure drop. At 0.4 m/s inflow velocity, the 50 %-porosity Diamond-Sheet variant achieves a peak average convection coefficient of 112,714.4 W/(m²·K) – 176 % and 209 % higher than Fin and Diamond-Solid structures, respectively, with a performance evaluation criterion (PEC) of 1.55.

下一代电子和航空航天设备的热管理需要先进的散热解决方案。虽然翅片式散热器通过扩大表面积来增强热传导，但其性能已不适合现代应用。三周期最小表面（TPMS）结构，特别是金刚石结构，由于其高比表面积和渗透性，提供了优越的传热能力。然而，现有的研究主要集中在铝合金或钛合金上，对铜基TPMS结构的研究很少。在这里，我们研究了选择性激光熔化（SLM）制造的CuCrZr金刚石结构，由于其优异的热/机械性能，它是一种很有前途的航空航天热管理材料。通过数值模拟和实验验证，分析了孔径和对流面积对翅片热性能的影响，并与传统翅片结构进行了对比。结果表明：相对密度的增大有利于对流换热，但增大了压降。在0.4 m/s入流速度下，50%孔隙率的金刚石-片结构的峰值平均对流系数为112,714.4 W/(m2·K)，分别比鳍状结构和金刚石-固体结构高176%和209%，性能评价标准（PEC）为1.55。

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引用次数: 0

Thermal Marangoni convection patterns and heat transfer characteristics in evaporating pendant droplets 蒸发垂坠液滴的热马兰戈尼对流模式和传热特性

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-01-05 DOI: 10.1016/j.ijthermalsci.2025.110655

Jun-Meng Hou, Wan-Yuan Shi

Pendant droplets widely exit in various engineering technologies such as spray cooling and medical diagnostics whereas thermal Marangoni convection in pendant droplets is lack of clearly understanding. The present paper aims to the dynamic behaviors and heat transfer characteristics of thermal Marangoni convection in pendant droplets during evaporation. The results found that three types of Marangoni convection patterns successively occurred in droplet with evaporation, i.e., they were unsteady thermocapillary convection, longitudinal rolls, and BM convection. Their surface temperature patterns and internal flow fields were carefully analyzed and the critical conditions for incipience of Marangoni convection instabilities were determined. Their Nusselt numbers and evaporation rates were measured and the influences of substrate temperature on them were investigated. These findings will be helpful for realizing Marangoni convection instabilities of pendant droplets.

悬垂液滴广泛存在于喷雾冷却、医学诊断等工程技术中，而悬垂液滴中的马兰戈尼热对流却缺乏明确的认识。本文研究了悬垂液滴蒸发过程中马兰戈尼热对流的动力学行为和传热特性。结果发现，液滴蒸发过程中先后出现了三种类型的Marangoni对流，即非定常热毛细对流、纵向涡旋对流和BM对流。仔细分析了它们的表面温度分布和内部流场，确定了马兰戈尼对流不稳定发生的临界条件。测定了它们的努塞尔数和蒸发速率，并研究了衬底温度对它们的影响。这些研究结果将有助于实现悬垂液滴的马兰戈尼对流不稳定性。

引用次数: 0

Performance optimization of aluminum slit fin-and-tube heat exchangers based on orthogonal experiments and response surface modeling 基于正交试验和响应面建模的铝狭缝翅片管换热器性能优化

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-01-05 DOI: 10.1016/j.ijthermalsci.2026.110659

Fang Wang , JiCheng Li , Guyao Zhang , Hong Liu , Xiaohan Zhang , Xianfei Liu , Bingjin Sun , Jialin Xu , Wei Guo

Aluminum slit fin-and-tube heat exchangers have garnered widespread attention owing to their unique economic and structural advantages. This study established a hierarchical optimization framework comprising orthogonal screening, analysis of variance (ANOVA) identification, and response surface modeling (RSM) optimization to enhance the overall performance evaluation coefficient (PEC) of heat exchangers under stable Re conditions. First, an orthogonal experimental design and ANOVA were employed to identify significant factors, which were then validated through experiments. Subsequently, RSM was conducted based on the significant factors to systematically evaluate the interactions among factors and implement continuous optimization. Under the PEC definition employed in this study, high-PEC regions typically correspond to combinations of high Nu and moderate f. The order of parameter significance is

P_{l} > P_{t} ≫ δ_{f} \approx S_{L} > S_{w} > S_{h}

, where the

P_{l}

and

P_{t}

distance parameters dominate the overall performance. The optimal parameter combination resulted in an average PEC that was 34.11 % higher than the original design and 1.99 % higher than the optimal combination obtained solely through orthogonal screening. The proposed two-stage Taguchi orthogonal-array screening + BBD–RSM refinement addresses the limitations of single-method/single-factor optimization by enabling Nu–f–PEC synergistic optimization with a small number of CFD runs, thereby providing robust quantitative guidance for geometric design of aluminum slit fin-and-tube heat exchangers.

铝缝翅片管换热器以其独特的经济和结构优势而受到广泛关注。为了提高换热器在稳定Re工况下的综合性能评价系数（PEC），建立了正交筛选、方差分析（ANOVA）识别和响应面模型（RSM）优化的层次优化框架。首先采用正交试验设计和方差分析确定显著性因素，然后通过实验进行验证。随后，基于显著因素进行RSM，系统评价各因素之间的相互作用，实现持续优化。在本文所采用的PEC定义下，高PEC区域通常对应于高Nu和中等f的组合。参数显著性的顺序为Pl>；Pt > δf≈SL>Sw>Sh，其中Pl和Pt距离参数主导了整体性能。优化后的最佳组合比原设计的平均PEC提高34.11%，比单正交筛选的最佳组合提高1.99%。提出的两阶段Taguchi正交阵列筛选+ BBD-RSM精细化方法，通过少量CFD运行实现nuf - pec协同优化，解决了单方法/单因素优化的局限性，从而为铝狭缝翅片管换热器的几何设计提供了可靠的定量指导。

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引用次数: 0