International Journal of Thermal Sciences最新文献_第2页

Experimental investigations of the convective and radiative synergistic heat transfer enhancement in turbine blade internal cooling channel 涡轮叶片内冷却通道对流与辐射协同强化换热的实验研究

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-06-01 Epub Date: 2026-01-21 DOI: 10.1016/j.ijthermalsci.2026.110713

Jie Liu , Jiabing Wang , Kun Yang

Although plenty of techniques are employed to improve cooling performance of turbine blades, the improvement was mainly achieved by enhancing convective heat transfer, while radiative heat transfer was not utilized. Besides, most of the existing investigations on the cooling channel were conducted under low thermal load conditions. To bridge these research gaps, this study presents a novel experimental investigation of the convective-radiative synergistic heat transfer enhancement in cooling channels with radiation enhancement plate. The experiments under high thermal load conditions up to 25,000 W m⁻² are carried out. Two kinds of novel channel configurations are developed with smooth or ribbed radiation enhancement plate, which can expand cold surfaces to strengthen radiation. The research indicates that, comparing with the traditional channel configuration, growths of total Nusselt number ratio as well as comprehensive thermal performance are 69.70 % and 24.62 %, respectively, by employing the smooth radiation enhancement plate. When inclined ribs are arranged on the radiation enhancement plate, growths of total Nusselt number ratio as well as comprehensive thermal performance are 82.58 % and 9.23 %, respectively, because airflow disturbance in the core region is intensified. The total Nusselt number ratio drops as Reynolds number grows, while it increases as wall heat flux rises. Besides, the approximate analysis method and the fitting method are developed to predict the channel wall temperature and the cooling performance, which is beneficial to overcome the limitation of equipment and experimental conditions for high thermal loads. In addition, the decoupling of convective and radiative heat transfer is achieved. Influences of radiative heat transfer on the overall thermal performance are also quantitatively explored.

虽然采用了大量的技术来提高涡轮叶片的冷却性能，但主要是通过加强对流换热来实现的，而没有利用辐射换热。此外，现有的冷却通道研究大多是在低热负荷条件下进行的。为了弥补这些研究空白，本研究提出了一种新的实验研究方法，对辐射增强板在冷却通道中的对流-辐射协同换热进行了研究。在高达25000 W m−2的高热负荷条件下进行了实验。研究了两种新型通道结构，分别采用光滑和肋形辐射增强板，对冷表面进行膨胀以增强辐射。研究表明，与传统通道构型相比，采用光滑辐射增强板后，总努塞尔数比和综合热性能分别提高了69.70%和24.62%。当在辐射增强板上设置斜肋时，总努塞尔数比和综合热性能分别增长了82.58%和9.23%，这是由于核心区气流扰动加剧所致。总努塞尔数比随雷诺数的增大而减小，随壁面热流密度的增大而增大。此外，提出了近似分析方法和拟合方法来预测通道壁温度和冷却性能，这有利于克服设备和实验条件对高热负荷的限制。此外，还实现了对流换热与辐射换热的解耦。并定量探讨了辐射传热对整体热性能的影响。

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引用次数: 0

Effects of fouling deposition on CAP1400 steam generator thermal-hydraulic performance via a coupled fouling–thermal-hydraulic model 污垢沉积对CAP1400蒸汽发生器热工性能的影响

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-06-01 Epub Date: 2026-01-31 DOI: 10.1016/j.ijthermalsci.2026.110732

Lanqing Qiao , Jianyu Tan , Qingzhi Lai , Wei Zeng , Junming Zhao

During long-term service, the thermal–hydraulic performance of steam generators gradually deteriorates as unavoidable fouling builds up on the secondary side. However, systematic studies of fouling-driven thermal–hydraulic behavior in the CAP1400 steam generator (SG) are still lacking, partly because the unit is in its early stage of commercial operation. Moreover, because fouling deposition and thermal–hydraulic behavior are intrinsically coupled, the problem becomes even more challenging to study. Therefore, a fully three-dimensional coupled fouling–thermal-hydraulic model was developed for the CAP1400 SG on the primary side and the secondary side. A quasi-steady multi-time-step coupling framework is developed to balance computational efficiency and coupling fidelity. The model was used to assess secondary-side fouling patterns and their impacts on flow and heat transfer after 360 days of deposition. The results show that deposits preferentially accumulate in the hot-side boiling region, particularly the U-bend. These locations should be prioritized for water-chemistry optimization and outage cleaning to mitigate thermal degradation and reduce the risk of under-deposit corrosion. Although the non-uniform fouling distribution strengthens cold-side heat transfer, the overall heat duty decreases. At 360 days, the cumulative fouling mass reaches 2082.28 kg and the heat duty drops by 6.44 %. Meanwhile, fouling reduces the outlet steam mass flow rate and lowers the secondary-side pressure drop. During operation, timely monitoring of the secondary-circuit steam-pressure margin consumption is required to ensure reliable performance over the unit's lifetime. These findings clarify the evolution of fouling in the CAP1400 SG and its impact on thermal performance, providing a basis for trend assessment and operational evaluation in long-term service.

蒸汽发生器在长期使用过程中，由于二次侧不可避免的积垢，其热工性能逐渐恶化。然而，由于CAP1400蒸汽发生器（SG）尚处于商业运行的早期阶段，对其污垢驱动的热水力行为的系统研究仍然缺乏。此外，由于污垢沉积和热液行为是内在耦合的，这一问题的研究变得更具挑战性。为此，建立了CAP1400 SG主侧和次侧全三维污垢-热工-水力耦合模型。为了平衡计算效率和耦合保真度，提出了准稳态多时间步耦合框架。该模型用于评估沉积360天后二次侧结垢模式及其对流动和传热的影响。结果表明，沉积物优先积聚在热侧沸腾区，尤以u型弯道为主。这些位置应优先进行水化学优化和停机清洗，以减轻热降解并降低沉积下腐蚀的风险。虽然不均匀污垢分布加强了冷侧传热，但总体热负荷降低。在360 d时，累积结垢质量达到2082.28 kg，热负荷下降6.44%。同时，结垢降低了出口蒸汽质量流量，降低了二次侧压降。在运行过程中，需要及时监测二回路蒸汽压力余量消耗，以确保机组在使用寿命期间的可靠性能。这些研究结果阐明了CAP1400 SG中积垢的演变及其对热性能的影响，为长期服役的趋势评估和运行评价提供了依据。

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引用次数: 0

Invariant key-node DEIM based on adaptive mesh refinement for efficient prediction of transient thermo-mechanical behavior in valves 基于自适应网格细化的不变键节点DEIM阀门瞬态热力学行为有效预测

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-06-01 Epub Date: 2026-01-29 DOI: 10.1016/j.ijthermalsci.2026.110719

Chaohui Huang, Hongjiang Wang, Han Dong, Weizhe Wang, Yingzheng Liu

This paper presents a novel integrated computational framework combining adaptive mesh refinement (AMR) and a hyper-reduced-order model (HROM) to overcome the prohibitive computational cost of high-fidelity transient thermo-mechanical analysis for geometrically complex, nonlinear high-temperature components. Conventional finite-element methods exhibit major limitations in resolving the intricate coupling between rapidly evolving thermal fields and stress evolution, particularly under severe thermal transients. The proposed framework employs AMR to dynamically concentrate computational resources in regions exhibiting steep gradients. Concurrently, the HROM, which integrates proper orthogonal decomposition and the discrete empirical interpolation method, achieves extreme dimensionality reduction while preserving critical nonlinear dynamics. Validation based on a representative high-temperature component under demanding steam turbine startup conditions demonstrates the exceptional performance of the proposed model: 33.5 × faster computation, 89.8 % lower memory requirement, and a peak thermal stress prediction error below 6.1 % relative to full-order simulation. Crucially, this approach resolves multi-time-scale thermo-mechanical interactions with high precision, accurately capturing the localized stress concentrations and critical thermal gradients essential for failure prediction. This dual-resolution strategy enables unprecedentedly efficient simulation of large-scale thermo-mechanical behavior under rapid thermal loading. Thus, it establishes a foundation for constructing physics-informed digital twins and significantly advances design optimization and reliability assessment for safety-critical energy systems.

本文提出了一种结合自适应网格细化（AMR）和超降阶模型（HROM）的新型集成计算框架，以克服几何复杂、非线性高温部件的高保真瞬态热力学分析的高昂计算成本。传统的有限元方法在解决快速发展的热场和应力演化之间的复杂耦合方面存在很大的局限性，特别是在严重的热瞬态下。该框架使用AMR动态地将计算资源集中在具有陡峭梯度的区域。同时，HROM将适当的正交分解和离散经验插值方法相结合，在保持临界非线性动力学的同时实现了极端降维。基于典型高温部件在汽轮机苛刻启动条件下的验证表明，所提出的模型具有优异的性能：与全阶模拟相比，计算速度提高了33.5倍，内存需求降低了89.8%，峰值热应力预测误差低于6.1%。至关重要的是，该方法高精度地解决了多时间尺度的热-机械相互作用，准确地捕获了失效预测所必需的局部应力集中和临界热梯度。这种双分辨率策略能够前所未有地高效模拟快速热载荷下的大规模热力学行为。因此，它为构建物理信息的数字孪生奠定了基础，并显著推进了安全关键能源系统的设计优化和可靠性评估。

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引用次数: 0

A pyro-piezo-phototronic regulation strategy for carrier modulation in a GaN PN junction GaN - PN结中载流子调制的热-压电-光电子调节策略

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-06-01 Epub Date: 2026-01-10 DOI: 10.1016/j.ijthermalsci.2026.110670

Mingkai Guo , Guoshuai Qin , Chunsheng Lu , Cuiying Fan , Minghao Zhao

The regulation of carrier distributions in piezoelectric semiconductors through piezo-phototronic and pyro-phototronic effects offers a promising pathway for developing tunable optoelectronic devices. In this paper, we propose a nonlinear pyro-piezo-phototronic model that accounts for the combined influences of ultraviolet radiation and externally applied mechanical stress. Unlike previous approaches that consider only piezoelectric or photoexcitation effects, this work extends the perturbation method to include pyroelectric contributions, enabling a comprehensive analysis of electromechanical field distributions under multi-field coupling. Our findings reveal that the polarity and direction of polarization charges at both ends of a GaN PN junction can be reversibly modulated by adjusting ultraviolet irradiation and mechanical loading. This controllable switching of polarized charges highlights a new avenue for functional regulation in piezoelectric semiconductors and expands their potential applications in next-generation optoelectronic and multifunctional devices.

压电半导体中载流子分布通过压电光电子效应和热光电子效应的调控为开发可调谐光电器件提供了一条有前途的途径。在本文中，我们提出了一个非线性的热-压电-光电子模型，该模型考虑了紫外线辐射和外部机械应力的综合影响。与之前只考虑压电或光激发效应的方法不同，这项工作将微扰方法扩展到包括热释电贡献，从而能够全面分析多场耦合下的机电场分布。我们的研究结果表明，GaN - PN结两端极化电荷的极性和方向可以通过调节紫外线照射和机械负载来可逆地调节。这种极化电荷的可控开关为压电半导体的功能调节提供了新的途径，并扩大了其在下一代光电和多功能器件中的潜在应用。

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引用次数: 0

Pore-scale analysis of non-ideal joint effect at foam-wall interface on the thermal performance of foam-filled channel 泡沫-壁界面非理想节理效应对泡沫填充通道热工性能的孔尺度分析

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-06-01 Epub Date: 2026-01-15 DOI: 10.1016/j.ijthermalsci.2026.110700

Bin Yin , Shibo Cheng , Xue Chen , Chuang Sun , Haifeng Sun

Flow and heat transfer in a foam-filled channel is investigated by a pore-scale simulation with special concern on the non-ideal joint effect between foam matrix and heating wall. The reticulated foam structures are constructed and represented based on the Weaire-Phelan model. The finite volume method is employed to solve the governing equations of mass, momentum, and energy, thereby determining the conjugate flow and thermal fields for the forced air convection within open-cell foams. The influences of non-contact location, ratio, and distribution regarding the global thermal behavior are systematically investigated. According to the results, non-contact between the foam and the base surface is a primary factor in the performance degradation of metal foam-based heat exchangers. Compared with complete contact, heat transfer is nearly weakened by 92 % under complete non-contact case with a negligible pressure drop change. The wall temperature difference exhibits a visible increment for different non-contact regions, especially at exit region (up to 73.28 K). The non-contact has at entrance region poses the greatest impact on the thermal performance. A significant link is revealed between the extent of non-contact area and the system's thermal performance, which significantly decreases with the increasing non-contact area ratio. The results demonstrate that joint integrity between the foam skeleton and the heating wall is crucial for heat transfer performance in practical engineering applications.

采用孔尺度模拟方法研究了泡沫填充通道内的流动和换热，特别关注了泡沫基质与加热壁之间的非理想联合效应。基于Weaire-Phelan模型构造了网状泡沫结构并进行了表征。采用有限体积法求解了质量、动量和能量的控制方程，从而确定了开孔泡沫内强迫空气对流的共轭流场和热场。系统地研究了非接触位置、比例和分布对整体热行为的影响。结果表明，泡沫与基面不接触是导致金属泡沫换热器性能下降的主要因素。与完全接触情况相比，完全非接触情况下的传热几乎减弱了92%，压降变化可以忽略不计。在不同的非接触区域壁面温差有明显的增加，特别是在出口区域（高达73.28 K）。入口区域的非接触对热工性能影响最大。非接触面积的大小与系统的热性能之间存在着显著的联系，随着非接触面积比的增加，系统的热性能显著降低。结果表明，在实际工程应用中，泡沫骨架与加热壁之间的连接完整性对传热性能至关重要。

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引用次数: 0

Spreading dynamics, heat transfer, and solidification behaviour of a single molten droplet impinging on a solid surface of different inclinations 单个熔滴撞击不同倾斜度固体表面时的扩散动力学、传热和凝固行为

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-06-01 Epub Date: 2026-01-17 DOI: 10.1016/j.ijthermalsci.2026.110692

Raju Chowdhury , Geoffrey Evans , Tom Honeyands , Brian J. Monaghan , David Scimone , Subhasish Mitra

Molten metal droplet-solid substrate interaction is an important physical phenomenon in diverse industrial applications from thermal spray coating to refractory wear remediation in basic oxygen steelmaking furnace. The process involves small spatio-temporal dynamics of competing inertia, surface tension and viscous force along with heat transfer and phase change. In this study, a 3D computational fluid dynamics (CFD) model was developed based on an interface-capturing volume of fluid (VOF) approach to simulate the spreading, and solidification behaviour of a molten droplet impinging (Weber number <150) on a low thermal conductivity surface (glass) oriented at different angles (0 < φ ≤ 90°). The solidification process involving conduction heat transfer at the solid surface as well as the liquid to solid phase change was modelled using the enthalpy-porosity method. The CFD model was validated by experiment involving high-speed imaging with good agreement. Two parameters - mushy zone constant and the thermal contact resistance were noted to play a significant role in correctly predicting the molten droplet spreading dynamics. It was noted although the droplet spread area increased with increasing Weber number in the normal impact case (zero-surface inclination), a decreasing trend was prominent when surface inclination was increased (oblique impact) at a fixed Weber number due to increasing effect of gravity in the tangential direction. The droplet cooling and subsequent solidification process was directly correlated to the spread area which increased at higher Weber number due to greater heat transfer at solid-liquid interface. Droplet cooling was noted to significantly decrease by the increase of surface inclination; however, solidification behaviour was rather less affected.

熔融金属液滴-固体基体相互作用是一种重要的物理现象，从热喷涂到碱性氧炼钢炉耐火材料磨损修复等多种工业应用中都有应用。这一过程涉及到小的时空动力学的竞争惯性，表面张力和粘性力，以及传热和相变。在本研究中，基于界面捕获流体体积（VOF）方法建立了三维计算流体动力学（CFD）模型，以模拟熔融液滴（Weber数<；150）在不同角度（0 < φ≤90°）取向的低导热表面（玻璃）上的扩散和凝固行为。采用焓孔法模拟了固体表面导热和液固相变的凝固过程。通过高速成像实验对CFD模型进行了验证，结果吻合较好。浆糊区常数和热接触电阻两个参数在正确预测熔滴扩散动力学方面起着重要作用。结果表明，在正常撞击情况下（零表面倾角），液滴扩散面积随韦伯数的增加而增加，但在固定韦伯数下，当表面倾角增加时（斜撞击），由于重力在切向上的作用增加，液滴扩散面积减小趋势明显。随着韦伯数的增加，固液界面处的热传递增大，液滴的冷却和凝固过程与扩散面积的增大有直接关系。液滴冷却随表面倾角的增加而显著降低；然而，凝固行为受到的影响较小。

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引用次数: 0

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 : 2026-06-01 Epub 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

Effective thermal conductivity of open-cell foams: Numerical study in structures composed of the space-filling Kelvin's tetrakaidekahedron 开孔泡沫的有效热导率：由空间填充开尔文四面体组成的结构的数值研究

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-06-01 Epub Date: 2026-01-10 DOI: 10.1016/j.ijthermalsci.2026.110687

Ioannis Psihias, Eustathios S. Kikkinides, Stergios G. Yiantsios

We consider the issue of the effective thermal conductivity of open-cell foams. Spatially periodic structures based on the space-filling Kelvin's tetrakaidecahedron are examined over a range of porosities from 0.88 to 0.99, and a range of solid to fluid thermal conductivity ratios from 10 to 8200. The heat conduction problem is analyzed numerically employing the finite element and the front-tracking method. The attractive characteristic of the methods is that simple, fixed, structured numerical grids may be employed, despite the complicated two-phase geometries involved. The numerical results obtained are in satisfactory agreement with the extensive and widely acknowledged experimental data of Calmidi and Mahajan [J. Heat Transfer 121 (1999), 466–471] and with established models in the literature. Interestingly, the results are also in excellent agreement with theoretical relations based on effective medium theories and cluster expansion techniques for low density random dispersions, suggesting that these relations may be very useful for quantitative predictions of effective properties in open-cell foams.

我们考虑了开孔泡沫的有效导热系数问题。基于空间填充开尔文四面体的空间周期结构在孔隙率为0.88至0.99，固体与流体导热系数为10至8200的范围内进行了研究。采用有限元法和前沿跟踪法对热传导问题进行了数值分析。这些方法吸引人的特点是，尽管涉及复杂的两相几何形状，但可以采用简单、固定、结构化的数值网格。所得到的数值结果与Calmidi和Mahajan的广泛和广泛认可的实验数据吻合得很好[J]。热传递121(1999)，466-471]和文献中已建立的模型。有趣的是，结果也与基于有效介质理论和低密度随机分散的团簇扩展技术的理论关系非常一致，这表明这些关系可能对开孔泡沫的有效性质的定量预测非常有用。

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引用次数: 0

A sensitivity analysis and computational assessment of topology optimization heat sink channel using a power law model 基于幂律模型的拓扑优化散热器通道灵敏度分析与计算评估

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-06-01 Epub Date: 2026-01-22 DOI: 10.1016/j.ijthermalsci.2026.110707

Amjid Rashid , Tenglong Cong , Hanyang Gu

In order to guarantee that electronics modules function at their design temperature for enhanced production and duration, thermal management is essential. The quantity of heat that needs to be dissipated per area rises in parallel with the compactness and power density of modern electronic equipment. The design of heat sinks that can sustain a low operational temperature and a small packing environment is therefore required. The geometric flexibility offered by topology optimization makes it a valuable tool for creating passive heat sinks that can reject as much heat as feasible in a constrained area. Convective heat transference problem established on the power law type non-Newtonian fluid is subjected to topology optimization. By optimizing non-Newtonian cooling device topology utilizing a material distribution-based optimization approach, a heat transfer maximization problem is investigated. Expending a design variable, specifically the “material density” to distinguish between the fluid and solid domains, is the methods core principle. An adjoint-based analysis procedure is used to update it depending on the gradient information. A numerical investigation is conducted into the non-Newtonian effect on the ideal arrangements of thermal devices. Our findings demonstrate that as the pressure differential or heat generation rises, extra branching flow channels are seen in the ideal designs. As compared to previous results, the current finding shows that the best arrangement is dependent on the power law index, and an advanced power law index can lead to lower flow rates and more complicated setups. Furthermore, the flow distribution design might offer the lowest hydrodynamic resistance, while the heat transfer increase design can reduce thermal resistance. Under the same conditions, the optimum design of the maximum power index problem performs significantly well in terms of heat transmission than the low index one. Our research could provide a mechanism for non-Newtonian fluid-based TO thermal devices, such as non-Newtonian heat sinks. The suggested design approach can be applied as a tool to offer cooling solutions for electronic components having a large heat flow thermal management.

为了保证电子模块在设计温度下工作，以提高产量和使用寿命，热管理是必不可少的。随着现代电子设备的紧凑性和功率密度的提高，每面积需要耗散的热量也在增加。因此，需要能够维持低工作温度和小包装环境的散热器设计。拓扑优化提供的几何灵活性使其成为制造被动散热器的宝贵工具，可以在受限区域内尽可能多地排除热量。建立在幂律型非牛顿流体上的对流换热问题进行了拓扑优化。利用基于材料分布的优化方法对非牛顿冷却装置拓扑结构进行优化，研究了传热最大化问题。使用设计变量，特别是“材料密度”来区分流体和固体域，是该方法的核心原理。采用基于伴随的分析方法，根据梯度信息对其进行更新。数值研究了非牛顿效应对热器件理想布置的影响。我们的研究结果表明，随着压差或热量产生的增加，在理想的设计中可以看到额外的分支流动通道。与以往的结果相比，目前的研究结果表明，最佳布置取决于幂律指数，而更高的幂律指数可能导致更低的流量和更复杂的设置。此外，流量分布设计可以提供最低的水动力阻力，而传热增加设计可以降低热阻力。在相同条件下，最大功率指数优化设计的传热性能明显优于低指数优化设计。我们的研究可以为非牛顿流体基TO热器件（如非牛顿散热器）提供一种机制。建议的设计方法可以作为一种工具，为具有大热流热管理的电子元件提供冷却解决方案。

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引用次数: 0

Numerical investigation of heat transfer characteristics in a turbine multistage sealing system based on fluid–solid coupling approach 基于流固耦合的涡轮多级密封系统传热特性数值研究

IF 5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Thermal Sciences

Pub Date : 2026-06-01 Epub Date: 2026-01-17 DOI: 10.1016/j.ijthermalsci.2026.110699

Yulong Yao , Jiawei Fan , Bo Hu , Chuan Wang

This study develops a high-fidelity fluid–solid thermal coupling model for a turbine multistage honeycomb labyrinth sealing system to systematically investigate the heat transfer mechanisms in critical regions. A hybrid meshing strategy with shared fluid–solid interface nodes and temperature-dependent solid material properties is employed to accurately capture convective heat transfer in the fluid domain and conductive heat diffusion in the solid domain. The analysis focuses on two honeycomb labyrinth seal (HLS) sections, the rotor and stator coupling interfaces, and the intermediate cavity, considering varying pressure ratios and rotational Reynolds numbers. Model reliability is confirmed through validation against published experimental and numerical benchmark data. Results reveal pronounced regional differences in heat transfer: the upstream HLS1 exhibits significantly higher heat transfer intensity than the downstream HLS2, with rotor-stator interface temperature rises of 4.14 % and 5.10 % in HLS1 compared to only 0.28 % and 0.43 % in HLS2 at a pressure ratio of 14.75. Local heat transfer coefficients show strong spatial fluctuations due to intensified turbulence and flow impingement. In the intermediate cavity, combined jet impingement and rotor-induced swirling flow generate a pronounced thermal boundary layer, with temperature variations reaching 21.33 % at y = 20 mm, while the left side shows only 1.33 %. The influence of rotation is more significant in HLS1 than in HLS2, leading to heterogeneous turbulence enhancement and heat transfer. Overall, this study quantitatively demonstrates localized and asymmetric heat transfer behaviors in multistage sealing systems, elucidating the coupled effects of pressure ratio and rotational motion, and providing a theoretical foundation for optimizing thermal management and structural design in high-efficiency turbine sealing applications.

本文建立了涡轮多级蜂窝迷宫密封系统的高保真流固耦合模型，系统地研究了关键区域的传热机理。采用共享流固界面节点和温度相关固体材料特性的混合网格策略，精确捕捉流体域的对流换热和固体域的导热扩散。考虑不同的压力比和旋转雷诺数，重点分析了两个蜂窝迷宫密封（HLS）截面、转子和定子耦合界面以及中间腔。通过对已发表的实验和数值基准数据的验证，验证了模型的可靠性。结果显示了明显的区域传热差异：上游HLS1的传热强度明显高于下游HLS2，在压力比为14.75时，HLS1的动静界面温度上升了4.14%和5.10%，而HLS2的动静界面温度仅上升了0.28%和0.43%。局部换热系数由于湍流和流动冲击的加剧而表现出强烈的空间波动。在中间空腔内，射流撞击和旋涡联合形成了明显的热边界层，在y = 20 mm处温度变化达到21.33%，而左侧仅为1.33%。旋转对HLS1的影响比HLS2更大，导致非均质湍流增强和换热。总体而言，本研究定量展示了多级密封系统的局部和非对称传热行为，阐明了压力比和旋转运动的耦合效应，为高效涡轮密封应用中的热管理和结构设计优化提供了理论基础。

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