International Journal of Heat and Fluid Flow最新文献_第5页

Numerical analysis of rib shape effects on entransy and field synergy in a ribbed sinusoidal wavy microchannel 肋形对肋形正弦波微通道中能量和场协同效应影响的数值分析

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-30 DOI: 10.1016/j.ijheatfluidflow.2025.110222

Qifeng Zhu, He Zhao, Jingwei Zeng, Sen Zhang, Wenqiang He, Haoxin Deng, Zezhong Wang

Previous research has demonstrated that symmetric sinusoidal wavy (SSW) microchannel heat sinks with rectangular ribs enhance heat transfer compared to ribless SSW channels. To further clarify the role of rib geometry, we conduct numerical simulations to analyze the effects of rib cross-sectional shape on flow and heat transfer characteristics in SSW channels using entransy dissipation and field synergy theory. The channels are equipped with internal ribs of six cross-sectional shapes (airfoil, backward triangle, diamond, ellipse, forward triangle and rectangle). The results show that the addition of ribs significantly improved the heat transfer, with the rectangular rib configuration (SSW-RR) achieving the highest overall performance factor of 1.227 at Re = 600. Ribs reduce entransy dissipation in channel troughs while generating high dissipation near flow detachment points, and this effect intensifies at higher Reynolds numbers. SSW-RR exhibits the lowest entransy dissipation values (1.20 × 10¹⁰ to 6.76 × 10⁹), indicating optimal heat transfer performance. Flow field analysis reveals that reverse vortices and large-angle fluid deflection enhance heat transfer, with the forward triangular rib configuration (SSW-FTR) showing the best field synergy (83.58 at Re = 300).

先前的研究表明，与无肋的对称正弦波（SSW）微通道散热器相比，矩形肋的对称正弦波（SSW）微通道散热器的传热效果更好。为了进一步阐明肋形几何的作用，我们利用能量耗散和场协同理论进行数值模拟，分析肋形截面形状对SSW通道内流动和换热特性的影响。通道配备六种截面形状的内肋（翼型，后三角形，菱形，椭圆形，前三角形和矩形）。结果表明，肋板的加入显著改善了换热性能，其中矩形肋板构型（SSW-RR）在Re = 600时获得了最高的综合性能因子1.227。肋板减少了通道槽内的能量耗散，同时在流动分离点附近产生了高耗散，这种效应在高雷诺数时增强。SSW-RR具有最低的能量耗散值（1.20 × 1010 ~ 6.76 × 109），传热性能最佳。流场分析表明，反向涡和大角度流体偏转增强了换热，其中前三角肋结构（SSW-FTR）的场协同效果最好（Re = 300时为83.58）。

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引用次数: 0

Thermal-hydraulic and structural analysis of a liquid-cooled heat sink with rotating twisted tape inserts 带旋转扭带插片的液冷散热器的热水力和结构分析

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-29 DOI: 10.1016/j.ijheatfluidflow.2025.110225

Abdullah Masoud Ali , Mohammad Ismail , Aldo Rona , Audrius Bagdanavicius , Areej Masoud Ali

This study investigates advanced thermal management techniques for liquid-cooled electronics, aiming to enhance cooling efficiency through innovative rotating twisted tape inserts in the heat sink. A water-cooled heat sink is analysed at an inlet temperature of 300 K, with Reynolds numbers ranging from 100 to 400, and a heat flux of 180,000 W/m². Five configurations are examined: a base case, a stationary twisted tape (ω = 0 rpm), and rotating twisted tapes at 300, 600, and 900 rpm. Results show that both stationary and rotating twisted tapes significantly reduce the base plate temperature compared to the base case. At Re = 400, temperature drops of 10.73 K, 13.12 K, 15.36 K, and 16.24 K are observed with ω = 0, 300, 600, and 900 rpm, respectively, demonstrating improved thermal performance that can enhance the reliability and lifespan of cooled electronics. While stationary tapes increase the friction factor due to intensified fluid-wall interactions, rotating tapes decrease the axial pressure drop by increasing fluid momentum. Fluid-structure interaction analysis indicates minimal deformation in copper and aluminium tapes, with maximum displacement occurring axially. Aluminium shows slightly higher deformation (2.850 × 10⁻⁵ mm) than copper (1.605 × 10⁻⁵ mm). These findings offer valuable insights for optimising thermal–hydraulic performance and structural integrity in electronic cooling systems.

本研究探讨了液冷电子产品的先进热管理技术，旨在通过在散热器中创新的旋转扭曲带插入来提高冷却效率。对进口温度为300 K、雷诺数为100 ~ 400、热流密度为180,000 W/m2的水冷式散热器进行了分析。测试了五种配置：基本情况，固定扭曲磁带（ω = 0 rpm）和旋转扭曲磁带（300,600和900 rpm）。结果表明，与基壳相比，固定和旋转扭带均能显著降低基板温度。在Re = 400时，当ω = 0,300, 600和900 rpm时，分别观察到温度下降10.73 K, 13.12 K， 15.36 K和16.24 K，这表明改进的热性能可以提高冷却电子设备的可靠性和寿命。固定带由于流体与壁面的相互作用加剧而增加了摩擦系数，而旋转带通过增加流体动量来减小轴向压降。流固耦合分析表明，铜和铝带的变形最小，轴向位移最大。铝的变形量（2.850 × 10−5mm）略高于铜（1.605 × 10−5mm）。这些发现为优化电子冷却系统的热工性能和结构完整性提供了有价值的见解。

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引用次数: 0

Influence of side jet orientation, stretching, and flow rate on thermal enhancement at the leading edge of a gas turbine blade 侧喷流方向、拉伸和流量对燃气轮机叶片前缘热增强的影响

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-29 DOI: 10.1016/j.ijheatfluidflow.2025.110194

Swati Prajapati, Amitesh Kumar

This study conducts a comprehensive numerical analysis of impingement cooling performance in a gas turbine blade leading-edge configuration, focusing on the effects of side jet orientation, jet stretching, and varying inlet velocities. The modified designs incorporating side jets are compared against a baseline case without side jets. Side jets are introduced at various inclination angles (5°, 22.5°, 45°, and 67.5°) and stretched to different heights (3 mm, 6 mm, and 12 mm) while preserving the same cross-sectional area as a circular nozzle. The influence of these parameters is evaluated for Reynolds numbers ranging from 11,790 to 21,220. The results indicate that side jet orientation notably influences the axial and circumferential Nusselt number distributions. Among the configurations, the 67.5° side jet provided the highest local cooling near upstream impingement zones due to enhanced recirculation and reduced jet spreading. Side jet stretching showed more pronounced effects at higher inclination angles, where the 12 mm side jet maintained stronger momentum and improved thermal performance compared to 3 mm side jets. Increasing the flow rate led to higher overall Nusselt numbers and lower friction factors, indicating enhanced thermal efficiency. Thermal–Hydraulic Performance (THP) analysis revealed that all the configurations achieved THP values greater than one, confirming the viability of the design modifications. The configuration with a 67.5° side jet inclination and 12 mm stretching consistently demonstrated the highest THP across all flow conditions, establishing it as one of the promising design concepts for enhancing heat transfer in the leading-edge region of gas turbine blades while maintaining acceptable pressure losses.

本文对燃气轮机叶片前缘结构的冲击冷却性能进行了全面的数值分析，重点研究了侧向射流方向、射流拉伸和不同进口速度对冲击冷却性能的影响。结合侧喷流的改进设计与没有侧喷流的基线情况进行了比较。侧射流以不同的倾角（5°，22.5°，45°和67.5°）引入，并拉伸到不同的高度（3毫米，6毫米和12毫米），同时保持与圆形喷嘴相同的横截面积。在雷诺数从11790到21220的范围内，对这些参数的影响进行了评估。结果表明，射流方向对轴向和周向努塞尔数分布有显著影响。在这些配置中，67.5°侧射流由于增强了再循环和减少了射流扩散，在上游撞击区附近提供了最高的局部冷却。侧喷流拉伸在倾角较大时效果更明显，与3 mm侧喷流相比，12 mm侧喷流保持了更强的动量，并改善了热性能。增加流量导致整体努塞尔数增加，摩擦系数降低，表明热效率提高。热水力性能（THP）分析显示，所有配置的THP值都大于1，证实了设计修改的可行性。在所有流动条件下，具有67.5°侧射流倾角和12 mm拉伸的配置始终显示出最高的THP，将其确立为有前途的设计概念之一，用于增强燃气轮机叶片前缘区域的传热，同时保持可接受的压力损失。

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引用次数: 0

Mathematical regulation of Gyroid-type TPMS structures for enhanced convective heat transfer 螺旋型TPMS结构强化对流换热的数学规律

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-27 DOI: 10.1016/j.ijheatfluidflow.2025.110227

Kaiwen Qin , Si Yang , Tingxiang Lv , Xijun Zhao , Xiaobin Tang

Triply periodic minimal surface (TPMS) structures have demonstrated significant potential for enhanced heat transfer owing to their compact structural design and excellent effective thermophysical properties. To further improve their convective heat transfer performance, precise control over their morphology has become a focus in current studies. In this study, a Gyroid-type TPMS structure was selected as the research subject, and three functional improvement methods—amplitude control, periodicity control, and phase control—were proposed. The effects of different control strategies on the morphological characteristics of the Gyroid structure were analyzed, and the flow and heat transfer characteristics of the improved Gyroid structure were calculated by numerical simulation and experimental measurement. The results show that with increasing values of the through-hole control factor (α), the peak temperature (T_max) of the Gyroid structure decreases by 19.0–33.6 K, while the convective heat transfer coefficient (h) increases by 29.4–33.7 %. Similarly, with increasing values of the wrinkle control factor (β), T_max decreases by 7.3–8.8 K, h increases by 5.4–7.9 %. The proposed methods not only provide a novel idea for further enhancing the heat transfer performance of Gyroid structures, but also offer valuable reference and theoretical support for the optimal design of other TPMS structures.

三周期最小表面（TPMS）结构由于其紧凑的结构设计和优异的有效热物理性能，在强化传热方面表现出了显著的潜力。为了进一步提高其对流换热性能，对其形态的精确控制已成为当前研究的热点。本研究以陀螺型TPMS结构为研究对象，提出了幅度控制、周期控制和相位控制三种功能改进方法。分析了不同控制策略对旋翼结构形态特性的影响，并通过数值模拟和实验测量计算了改进后的旋翼结构的流动和传热特性。结果表明：随着通孔控制因子（α）的增大，陀螺结构的峰值温度（Tmax）降低19.0 ~ 33.6 K，对流换热系数(h)增加29.4 ~ 33.7%；同样，随着皱纹控制因子（β）的增加，Tmax降低7.3 ~ 8.8 K， h增加5.4 ~ 7.9%。所提出的方法不仅为进一步提高陀螺结构的传热性能提供了新的思路，也为其他TPMS结构的优化设计提供了有价值的参考和理论支持。

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引用次数: 0

Porous-medium modelling and thermo-hydraulic characteristics of multi-stage perforated plate arrangement 多级穿孔板布置的多孔介质模拟及热水力特性

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-27 DOI: 10.1016/j.ijheatfluidflow.2025.110217

Arijit Das, Tripti Sekhar Datta, Tapas Kumar Nandi

This study proposes a novel porous-medium modelling of multi-stage perforated plate arrangements to investigate their thermo-hydraulic performance while significantly reducing the computational cost of resolving small perforations. In this approach, the Darcy-Forchheimer equation is introduced as a source term in the Navier-Stokes momentum equation to represent the pressure losses induced by perforations, while the heat transfer between the fluid and plates is captured using the local thermal non-equilibrium(LTNE) formulation. However, the model requires values of permeability, Forchheimer coefficient, pressure loss coefficient, and Colburn factor. These parameters are determined by numerical simulations of a single and two-stage perforated plate arrangements with fully resolved perforated plate. The numerical model was validated with available experimental data. Using the simulated data for aligned and misaligned-holes configurations, correlations are developed over porosities of 0.2–0.3 and pore-scale Reynolds numbers (Re) of 10–4000. A comparison between fully resolved perforated plates and their porous-medium counterparts shows that the porous model offers substantial reductions in the number of mesh elements and computational time, while maintaining a good accuracy. Parametric studies are conducted to evaluate the effects of geometrical parameters and Re on pressure drop and heat transfer. The results show that heat transfer increases with porosity, thickness-to-perforation diameter (t/d) ratio, and Re, whereas pressure drop decreases with porosity but increases with both t/d ratio and Re. Increasing stage distance raises both heat transfer and pressure drop for aligned-holes, while misaligned-holes show the opposite trend. Overall, this work will be useful in modelling devices consists of multi-stage perforated plate arrangement.

本研究提出了一种新的多孔介质模型，用于研究多级穿孔板布置的热水力性能，同时显著降低求解小穿孔的计算成本。在这种方法中，Darcy-Forchheimer方程作为源项引入到Navier-Stokes动量方程中，以表示穿孔引起的压力损失，而流体和板之间的传热则使用局部热非平衡（LTNE）公式进行捕获。然而，该模型需要渗透率、Forchheimer系数、压力损失系数和Colburn因子的值。这些参数是通过数值模拟确定的单级和两级穿孔板布置与完全分解穿孔板。用已有的实验数据对数值模型进行了验证。利用对准孔和不对准孔的模拟数据，在孔隙度为0.2-0.3和孔隙尺度雷诺数（Re）为10-4000时建立了相关关系。完全解析的多孔板与多孔介质模型的对比表明，多孔模型在保持良好精度的同时，大大减少了网格单元的数量和计算时间。对几何参数和Re对压降和传热的影响进行了参数化研究。结果表明：换热随孔隙度、孔厚/射孔直径（t/d）比和Re增大而增大，压降随孔隙度减小而增大，但随t/d比和Re增大而增大。准直孔的换热和压降随级距增大而增大，准直孔则相反。总的来说，这项工作将有助于模拟由多级穿孔板排列组成的装置。

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引用次数: 0

Regression analysis of heat transfer in twin slot jet impingement with computational fluid dynamics and machine learning techniques 基于计算流体力学和机器学习技术的双狭缝射流冲击传热回归分析

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-26 DOI: 10.1016/j.ijheatfluidflow.2025.110220

Homin Kim , Tae Hee Lee , Sanghoon Kim , Sang Lee , Jung-Wuk Hong

This study proposes a hybrid methodology coupling computational fluid dynamics (CFD) and machine learning to analyze the heat transfer characteristics of unconfined twin slot jets impinging on a heated wall. We develop an accurate numerical model, apply machine learning to identify the key parameters, and subsequently perform a regression analysis across a wide range of operating conditions. Specifically, a high-fidelity two-dimensional CFD model is developed, and the solutions are obtained using the

k

–

ɛ

turbulence model. The model is validated by comparing the simulated Nusselt number distributions with experimental results on the impingement surface. A large dataset of 1575 simulations is constructed by systematically varying four operating conditions of the jet: jet velocity, nozzle spacing, wall temperature, and jet height. This study employs machine learning for objective feature selection to facilitate the development of interpretable regression models. Four machine learning algorithms, including multi-layer perceptron, random forest, gradient boosting, and support vector regression, are applied to the dataset, identifying jet velocity and jet height as the key parameters governing heat transfer. Focusing on these key parameters, we identify a critical flow transition at a threshold jet height of 12 times the nozzle width, which separates the flow behavior into near- and far-field regimes. For each regime, separate polynomial and power-law regression models are obtained to calculate the average and maximum Nusselt numbers. This methodological approach effectively bridges the gap between data-driven analysis and practical engineering design, providing accurate and effective predictive tools for thermal analysis.

本文提出了一种结合计算流体力学（CFD）和机器学习的混合方法来分析无约束双缝射流撞击加热壁面的传热特性。我们开发了一个精确的数值模型，应用机器学习来识别关键参数，随后在广泛的操作条件下进行回归分析。具体而言，建立了高保真二维CFD模型，并采用k - ε湍流模型求解。将模拟的努塞尔数分布与撞击表面的实验结果进行了比较，验证了模型的有效性。通过系统地改变射流的四种运行条件：射流速度、喷嘴间距、壁面温度和射流高度，构建了1575个大型模拟数据集。本研究采用机器学习进行客观特征选择，以促进可解释回归模型的发展。将多层感知器、随机森林、梯度增强和支持向量回归等四种机器学习算法应用于数据集，确定了射流速度和射流高度作为控制传热的关键参数。针对这些关键参数，我们确定了阈值射流高度为喷嘴宽度的12倍时的临界流动过渡，该过渡将流动行为分为近场和远场。对于每个区域，分别获得多项式和幂律回归模型来计算平均和最大努塞尔数。这种方法有效地弥合了数据驱动分析与实际工程设计之间的差距，为热分析提供了准确有效的预测工具。

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引用次数: 0

Influence of turbulence inflow conditions on aeroacoustics of wall-bounded flows 湍流入流条件对壁面流动气动声学的影响

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-26 DOI: 10.1016/j.ijheatfluidflow.2025.110216

Ronith Stanly , Eman Bagheri , Timofey Mukha , Philipp Schlatter

A scale-resolving simulation of a turbulent boundary layer (TBL) requires an inflow condition that introduces turbulence into the domain. The boundary values must accurately approximate real turbulent structures in order to minimize the inflow adaption and to allow for sustained growth of the TBL. In practice, all inflow conditions incur an error on the flow field directly downstream. This error is typically quantified as the distance from the inlet at which the velocity statistics recover correct values. However, this measure is insufficient for simulations where evaluating acoustic pressure is an important outcome, necessitating a quantification of the error in the pressure field. This aspect of inflow generation is currently not addressed in the literature and constitutes the main topic of this article. We show that violation of the continuity equation near the inflow region generates spurious pressure fluctuations over the entire domain, leading to poor sound prediction results in low Mach number regimes. In particular, we look at three known inflow generation methods (namely, precursor simulations, the synthetic eddy method, and recycling using an upstream open channel flow) and evaluate how silent they are. For evaluation, the sensitive case of a TBL developing over a flat plate is used as the test case. The recycling method satisfies the divergence-free condition and introduces the least amount of spurious numerical noise to the sound field while giving reasonably good agreement in terms of the overall development of the TBL.

湍流边界层（TBL）的尺度解析模拟需要引入湍流进入区域的入流条件。边界值必须精确地近似真实的湍流结构，以便最小化流入适应并允许TBL的持续增长。实际上，所有入流条件都会对下游流场产生误差。这个误差通常被量化为从入口到速度统计恢复正确值的距离。然而，这种方法在模拟中是不够的，因为评估声压是一个重要的结果，需要对压力场的误差进行量化。流入产生的这一方面目前尚未在文献中得到解决，并构成本文的主要主题。我们表明，在流入区域附近的连续性方程的破坏会在整个区域产生虚假的压力波动，导致低马赫数区域的声音预测结果不佳。特别地，我们研究了三种已知的流入生成方法（即前体模拟、合成涡流法和利用上游明渠流的回收），并评估了它们的沉默程度。为了评估，TBL在平板上发展的敏感情况被用作测试用例。该方法满足无散度条件，对声场引入了最少的伪数值噪声，同时在TBL的整体发展方面给出了相当好的一致性。

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引用次数: 0

Direct numerical simulation of installation effects on airfoil noise 安装对翼型噪声影响的直接数值模拟

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-26 DOI: 10.1016/j.ijheatfluidflow.2025.110207

Ziyang Zhou , Stéphane Moreau , Marlène Sanjosé

To evaluate installation effects on velocity statistics and its influence on farfield noise, three Direct Numerical Simulations (DNS) have been run using the Lattice-Boltzmann Method with the PowerFLOW software on the Controlled-Diffusion (CD) airfoil at a Reynolds number of 150 000 and 8 degrees angle of attack installed in the Universite de Sherbrooke (UdeS) wind tunnel. Differences in setup between these DNS simulations are the addition of voxel refinements and turbulent trips to the simulation setup for better capturing of the jet shear layer downstream of the wind tunnel nozzle lip. Results show that the airfoil boundary layer displacement thickness, momentum thickness and shape factor are slightly increased after jet shear layer refinement due to an increase in mean angle of attack caused by a change in shear layer state. Despite these changes caused by the mixing layer state, maximum Reynolds stress magnitude near the trailing edge of the airfoil was changed by only 6%. This indicates that adjustments to the wall pressure statistics which are relevant to trailing edge noise generation was only marginal. As such, changes to boundary layer statistics had limited impact on far-field noise in the mid-frequency range in this operating state.

为了评估安装对速度统计的影响及其对远场噪声的影响，采用格点-玻尔兹曼方法和PowerFLOW软件对安装在雪布鲁克大学（UdeS）风洞中的受控扩散（CD）翼型进行了3次直接数值模拟（DNS），雷诺数为15万，迎角为8度。这些DNS模拟设置的不同之处在于，为了更好地捕捉风洞喷嘴唇部下游的射流剪切层，在模拟设置中增加了体素细化和湍流行程。结果表明：射流剪切层细化后翼型边界层位移厚度、动量厚度和形状因子均略有增加，这是由于剪切层状态改变导致平均迎角增大所致。尽管这些变化是由混合层状态引起的，但翼型后缘附近的最大雷诺应力值仅变化了6%。这表明对与后缘噪声产生相关的壁面压力统计数据的调整只是微不足道的。因此，在这种工作状态下，边界层统计量的变化对中频范围内远场噪声的影响有限。

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引用次数: 0

Increasing bushing temperature via a heating tube for performance enhancement of ion implanters 通过加热管提高套管温度以提高离子注入器的性能

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-24 DOI: 10.1016/j.ijheatfluidflow.2025.110214

Yoon Hoo Shin , Hyo Jun Sim , Jong Jin Hwang , Seung Jae Moon

This study aims to enhance the performance of an ion implanter by improving temperature control through a heating tube integrated within the bushing. In an ion implanter, gases such as PH₃, AsH₃, BF₃, and GeF₄ are ionized by applying high voltages of up to 80 kV. Consequently, an ion beam is extracted from the electrode. However, residual gases are deposited inside the bushing under relatively low operating temperatures. Consequently, a leakage current flows through the bushing due to the deposited residual gas layer. This results in arcing from the potential differences across the bushing. To address this issue, this study designs and implements a heating tube within the bushing and circulates a heating fluid via the tube to increase the bushing’s temperature. The proposed heating system prevents gas deposition and enhances the efficiency of the deposition process. The optimal condition—defined as achieving a bushing wall temperature of 60°C with minimal energy input—was determined as a FC-3283 flow rate of 24 LPM with an inlet temperature of 100°C. The effectiveness of this solution is evaluated through a combination of experiments and computational fluid dynamics simulations. The experimental results corroborate the simulation outcomes. This integrated experimental–simulation approach is expected to significantly enhance deposition process efficiency. These findings offer valuable insights for optimizing ion implantation performance and reducing the frequency of bushing replacements.

本研究旨在通过集成在套管内的加热管改善温度控制来提高离子注入器的性能。在离子注入器中，通过施加高达80kv的高压使PH3、AsH3、BF3和GeF4等气体电离。因此，从电极中提取出离子束。然而，在相对较低的工作温度下，残余气体沉积在衬套内。因此，由于沉积的残余气体层，泄漏电流流过套管。这导致电弧从电位差横跨衬套。为了解决这一问题，本研究在套管内设计并实现了一个加热管，并通过加热管循环加热流体来提高套管的温度。所提出的加热系统可以防止气体沉积，提高沉积过程的效率。最优条件为FC-3283的流量为24 LPM，进口温度为100℃，以最小的能量输入实现60℃的衬套壁温度。通过实验和计算流体力学模拟相结合的方法对该方法的有效性进行了评价。实验结果与仿真结果相吻合。这种集成的实验模拟方法有望显著提高沉积过程的效率。这些发现为优化植入性能和减少套管更换频率提供了有价值的见解。

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引用次数: 0

Optimization of the cooling performance of ribbed channels by combining neural networks and genetic algorithms 结合神经网络和遗传算法优化肋形通道的冷却性能

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow

Pub Date : 2025-12-24 DOI: 10.1016/j.ijheatfluidflow.2025.110224

Shao-Fei Zheng , Jia-Xing Meng , Hua-Dong Shi , Yi-Feng Wang , Shu-Rong Gao , Yan-Ru Yang , Bo Gao , Xiao-Dong Wang

In gas turbine engines, efficient heat transfer following less friction loss is extremely preferable for the cooling of turbine blades, because of the limited supply of the cooling air. To maximize the cooling effect of the commonly utilized ribbed channel, the back propagation neural network (BPNN) model and the genetic algorithm (GA) are combined to construct an optimization tool by exactly modeling the complex nonlinear relationship between the influencing factors and cooling performance. The coupling influences of the channel aspect ratio (W/H = 0.5 ∼ 4.0), the pitch ratio of ribs (P/e = 20 ∼ 5), and the Reynolds number (Re = 20, 000 ∼ 100, 000) are comprehensively analyzed using the Nusselt number and overall performance factor as the target function. The results state that using the Nusselt number as the target function, the relatively large aspect ratio and small pitch ratio are recommended due to the heat transfer enhancement of the flow impingement effect with the rib-induced flow separation. Considering both the heat transfer enhancement and the increased friction loss, the overall performance factor presents a highly nonlinear relationship with those influencing parameters, and the relatively small aspect ratio and large pitch ratio are suggested to improve the comprehensive cooling performance. Using the GA-BPNN optimization method, a great increase of 16.98 %∼30.67 % is achieved for the overall performance factor in the current operating conditions. Finally, the GA-BPNN method is demonstrated as powerful and efficient for improving the ribbed cooling channel.

在燃气涡轮发动机中，由于冷却空气的供应有限，在摩擦损失较小的情况下，高效的传热对于涡轮叶片的冷却是极其可取的。为了使常用的肋形通道冷却效果最大化，将反向传播神经网络（BPNN）模型与遗传算法（GA）相结合，通过精确建模影响因素与冷却性能之间复杂的非线性关系，构建了优化工具。耦合通道宽高比的影响(0.5 W / H =  ∼ 4.0),肋骨的螺距比(P / e = 20 ∼ 5),和雷诺数(Re = 000 ∼ 100年,000年)进行了全面分析使用努塞尔特数和整体性能因素作为目标函数。结果表明，以Nusselt数为目标函数，由于肋诱导流动分离强化了流动冲击效应的传热，建议采用较大的展弦比和较小的节距比。考虑到传热增强和摩擦损失的增加，综合性能因子与这些影响参数呈高度非线性关系，建议采用较小的展弦比和较大的节距比来提高综合冷却性能。使用GA-BPNN优化方法，在当前运行条件下，总体性能因子实现了16.98 % ~ 30.67 %的大幅提高。最后，验证了GA-BPNN方法对肋形冷却通道的改进效果。

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引用次数: 0