Applied Thermal Engineering最新文献

Heat transfer tuning-oriented optimization and screening of triply periodic minimal surface structure-phase change material composites 面向传热调谐的三周期最小表面结构相变材料复合材料优化与筛选

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-04-01 Epub Date: 2026-02-23 DOI: 10.1016/j.applthermaleng.2026.130405

Kening Yan , Junfei Liang , Ranran Yu , Tingting Zhou , Yanhui Feng , Lin Qiu

Phase change materials (PCMs) are ideal candidates for thermal energy storage systems due to their high latent heat, small phase change temperature fluctuation and excellent thermal stability. However, low intrinsic thermal conductivity represents a critical limitation that severely restricts practical engineering applications. In this study, three triply periodic minimal surface (TPMS) configurations (Diamond, Primitive and Gyroid) were generated via the implicit function method. By adopting the numerical simulation method and taking solid-liquid interface evolution, temperature distribution, average convective heat transfer coefficient and total melting time as the key indices, the structural optimization of TPMS-PCM composite systems was conducted for TPMS configurations, porosity and pore gradients. The simulation results showed that the Diamond-type TPMS-PCM exhibited the optimal heat transfer performance, with its total melting time reduced by 8.7% and 3.8% vs. Gyroid and Primitive configurations, respectively. The positive pore gradient structure outperformed uniform and negative structures, with the average convective heat transfer coefficient enhanced by a maximum of 8.1%. Visual experiments indicated that pure paraffin had a total melting time of 2179 s, and TPMS-PCM exhibited a drastically enhanced melting rate due to the superior thermal conductivity of TPMS skeletons, with the Diamond-type TPMS-PCM achieving a total melting time of only 320 s, an 85.3% reduction relative to pure paraffin. Moreover, synergistic regulation of porosity and pore gradient further accelerated PCM melting, cutting the time to reach solid-liquid phase-change temperature by a maximum of 20.5%. The established TPMS thermal optimization method underpins porous PCM composite parameter optimization, guiding their engineering preparation and high-efficiency thermal management design.

相变材料具有潜热高、相变温度波动小、热稳定性好等优点，是热储能系统的理想候选材料。然而，低固有热导率是一个严重限制实际工程应用的关键限制。本文采用隐函数法生成了三种三周期极小曲面（Diamond、Primitive和Gyroid）构型。采用数值模拟方法，以固液界面演化、温度分布、平均对流换热系数和总熔融时间为关键指标，对TPMS- pcm复合体系的构型、孔隙率和孔隙梯度进行了结构优化。模拟结果表明，金刚石型TPMS-PCM具有最佳的传热性能，其总熔化时间比Gyroid和Primitive构型分别缩短了8.7%和3.8%。正孔梯度结构优于均匀孔梯度结构和负孔梯度结构，平均对流换热系数最大提高8.1%。目测结果表明，纯石蜡的总熔融时间为2179 s，而TPMS- pcm的熔融速度由于TPMS骨架的优异导热性而大大提高，其中金刚石型TPMS- pcm的总熔融时间仅为320 s，比纯石蜡减少了85.3%。此外，孔隙率和孔隙梯度的协同调节进一步加速了PCM的熔化，使达到固液相变温度的时间最多缩短了20.5%。所建立的TPMS热优化方法为多孔PCM复合材料的参数优化奠定了基础，指导了多孔PCM复合材料的工程制备和高效热管理设计。

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引用次数: 0

Predictive optimal dispatch for heterogeneous all-parallel chiller plant systems considering convex surrogate models and real-time operation constraints 考虑凸代理模型和实时运行约束的异构全并联冷水机组系统预测最优调度

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-04-01 Epub Date: 2026-02-20 DOI: 10.1016/j.applthermaleng.2026.130344

Shanshuo Xing , Zhiwei Li , Zhe Wang , Jili Zhang

The increasing scale and operational complexity of heterogeneous all-parallel chiller plants pose significant challenges for real-time optimal operation, especially when equipment on/off constraints and load-side evolution are considered. This study proposes a predictive optimal dispatch framework for heterogeneous chiller plant systems that explicitly incorporates minimum up/down time (MU/DT) constraints and multi-step load-side prediction. Input convex neural networks (ICNNs) are used to build convex surrogate models for chillers, chilled-water pumps, condenser-water pumps and cooling towers. They are employed for balancing model fidelity and computational tractability and enhancing the convergence and robustness of continuous optimization. On this basis, a four-step XGBoost predictor is developed for load-side forecasting of cooling load and chilled water return temperature. A bi-level optimization scheme is then formulated. Wherein an upper-level depth-first search (DFS) with engineering-informed pruning and filtering determines feasible on/off sequences, and a lower-level gradient-based solver with ICNN surrogate models optimizes continuous variables. A case study on a hospital chiller plant demonstrates that the proposed method achieves an average energy-saving ratio of 7.92% compared with the baseline of a rule-based strategy. The results demonstrate a prevention of the frequent cycling and power spikes that are observed in static optimization. Pruning and filtering strategies reduce the number of equivalent sequences from 2⁴⁸ (exhaustive search) to 4–384, and each relaxed subproblem is solved in about 0.96 s. Robustness tests under three typical load conditions demonstrate highly concentrated optimal values without outliers, indicating strong reproducibility of the proposed method. Overall, the proposed method provides an effective reference for practical engineering applications of predictive dispatch in heterogeneous all-parallel chiller plants.

异构全并联冷水机组的规模和运行复杂性不断增加，对实时优化运行提出了重大挑战，特别是在考虑设备开/关约束和负荷侧演变的情况下。本研究提出了一种针对异构冷水机组系统的预测优化调度框架，该框架明确地结合了最小启动/停机时间（MU/DT）约束和多步骤负载侧预测。输入凸神经网络（icnn）用于建立冷水机组、冷水泵、冷凝器水泵和冷却塔的凸代理模型。它们用于平衡模型保真度和计算可跟踪性，增强连续优化的收敛性和鲁棒性。在此基础上，开发了用于冷负荷和冷冻水回温负荷侧预测的四步XGBoost预测器。然后制定了双层优化方案。其中，具有工程信息修剪和滤波的上层深度优先搜索（DFS）确定可行的开/关序列，而具有ICNN代理模型的下层基于梯度的求解器优化连续变量。以某医院冷冻厂为例，与基于规则的策略相比，该方法的平均节能率为7.92%。结果表明，可以防止在静态优化中观察到的频繁循环和功率峰值。剪枝和过滤策略将等效序列的数量从248个（穷极搜索）减少到4-384个，每个松弛子问题的求解时间约为0.96 s。三种典型负载条件下的稳健性测试表明，最优值高度集中，无异常值，表明该方法具有较强的可重复性。该方法为异构全并联冷水机组预测调度的实际工程应用提供了有效的参考。

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引用次数: 0

Novel multi-condenser hybrid ground source heat pump system incorporated to vapour compressor refrigeration cycle with internal heat exchanger assessed with multi-objective genetic algorithm 采用多目标遗传算法对蒸汽压缩机制冷循环内换热器多冷凝器混合地源热泵系统进行了评价

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-04-01 Epub Date: 2026-02-26 DOI: 10.1016/j.applthermaleng.2026.130403

Abu Hena Toslim, Nafisa Riza Chowdhury, Md. Hasan Ali

Ground-source systems take advantage of the stability of the ground temperatures, allowing for performance levels higher than those of air-source systems. Nevertheless, in areas where cooling is the major requirement, the constant rejection of heat eventually depletes the ground's thermal capacity, gradually degrading the performance of ground-source systems. Internal heat exchangers also contribute to the problem by increasing the compressor's superheat, thereby accelerating the saturation of the ground. In addition, GSHPs suffer from thermal saturation during operation in hot climates. Therefore, there is a need for a heat-rejection system that minimizes heat transfer to the ground while maintaining GSHP performance. This study has proposed a multi-condenser vapour compression refrigeration system approach for solving the condenser load management problems in GSHPs using ground heat exchangers. The conventional GSHP has a reduced COP due to the integration of IHX. Furthermore, the VCR system integrated with the IHX has a greater load on the condenser. Therefore, three theoretical models are proposed and analyzed for the GSHP coupled with the GHE. The load management strategies for the GSHP are classified into air-assisted condenser (AAC) and ground heat exchanger-assisted condenser (GHEAC). Three models are developed for the GSHP coupled with the GHE. These include the baseline model coupled with the GHE, the conventional GSHP coupled with the IHX, and the conventional GSHP coupled with the GHE. The load management strategies for the GSHP are classified into air-assisted condenser (AAC) and ground heat exchanger-assisted condenser (GHEAC). The models are developed as permutations of the two condensers. The AAC model performs best under standard conditions, followed by the GHEAC model. For the AAC model, the amount of heat transferred to the ground is reduced by 63.44% relative to the baseline model. In addition, the exergy efficiency improves by 12.62%, while the COP decreases by 1.25%. In terms of COP, the baseline model performs best, followed by the model in which the ambient air is pre-cooled using the GHE before it is supplied to the condenser to cool the superheated refrigerant.

地源系统利用地面温度的稳定性，使其性能水平高于空气源系统。然而，在以冷却为主要需求的地区，不断排出热量最终会耗尽地面的热容量，逐渐降低地源系统的性能。内部热交换器通过增加压缩机的过热度，从而加速地面的饱和，也有助于解决这个问题。此外，地源热泵在炎热气候下运行时遭受热饱和。因此，需要一个散热系统，以尽量减少热量传递到地面，同时保持地源热泵的性能。针对地源热泵中冷凝器负荷管理问题，提出了一种多冷凝器蒸汽压缩制冷系统方案。由于集成了IHX，传统地源热泵的COP降低了。此外，与IHX集成的VCR系统在冷凝器上有更大的负载。为此，本文提出并分析了地源热泵与地源热泵耦合的三种理论模型。地源热泵负荷管理策略分为空气辅助冷凝器（AAC）和地面热交换器辅助冷凝器（GHEAC）。建立了地源热泵与地源热泵耦合的三个模型。这些包括与GHE耦合的基线模型，与IHX耦合的传统地源热泵，以及与GHE耦合的传统地源热泵。地源热泵负荷管理策略分为空气辅助冷凝器（AAC）和地面热交换器辅助冷凝器（GHEAC）。这些模型是作为两个冷凝器的排列而发展起来的。AAC模型在标准条件下表现最好，其次是GHEAC模型。对于AAC模型，传递给地面的热量相对于基线模型减少了63.44%。火用效率提高了12.62%，COP降低了1.25%。在COP方面，基线模型表现最好，其次是使用GHE对环境空气进行预冷，然后将其供应给冷凝器以冷却过热制冷剂的模型。

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引用次数: 0

Selection of high-performance phase change materials for enhanced building thermal management using hybrid multi-criteria decision-making 使用混合多标准决策选择高性能相变材料以增强建筑热管理

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-04-01 Epub Date: 2026-02-25 DOI: 10.1016/j.applthermaleng.2026.130393

Anas Azhar , Oumaima Imghoure , Zohir Younsi , Naoual Belouaggadia , Nassim Sebaibi

Phase change materials have attracted significant attention as highly effective and innovative solutions for thermal energy storage and temperature regulation. Due to their high latent heat capacity, PCMs can be incorporated into various applications to enhance thermal management, including walls, floors, bricks, gypsum, and insulation. However, selecting the most appropriate PCM remains a complex decision-making process due to the diversity of choices and multiple evaluation criteria.

The present research proposes a hybrid multi-criteria decision-making framework for the ranking and selection of optimal phase change materials for building applications. The evaluation criteria were weighted using a combination of objective and subjective methods. The final ranking of the alternatives was then determined using four multi-criteria decision-making techniques.

Sixteen PCMs with melting temperatures in the human comfort range (18–28 °C) were evaluated based on 16 criteria covering thermophysical, kinetic, economic, and environmental aspects. The results showed that A28 ranked first (260 kJ.kg⁻¹), followed by A26 (230 kJ.kg⁻¹) and PureTemp27 (202 kJ.kg⁻¹). The superior thermal behavior of these PCMs was further validated through building energy simulations in three different climate zones, highlighting their effectiveness in regulating temperature and enhancing thermal management.

相变材料作为一种高效、创新的热能储存和温度调节解决方案受到了广泛关注。由于其高潜热容量，pcm可以纳入各种应用，以加强热管理，包括墙壁，地板，砖，石膏和绝缘。然而，由于选择的多样性和多种评价标准，选择最合适的PCM仍然是一个复杂的决策过程。本研究提出了一种混合多标准决策框架，用于建筑应用中最优相变材料的排序和选择。采用客观和主观相结合的方法对评价标准进行加权。然后使用四种多标准决策技术确定备选方案的最终排名。根据热物理、动力学、经济和环境方面的16项标准，对熔融温度在人体舒适范围内（18-28°C）的16种pcm进行了评估。结果表明，A28以260 kJ的最高效率位居首位。kg−1)，其次是A26 （230 kJ）。PureTemp27 （202 kg .kg−1）。通过三种不同气候带的建筑能源模拟，进一步验证了这些相变材料优越的热性能，突出了它们在调节温度和加强热管理方面的有效性。

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引用次数: 0

A techno-economic design framework and analysis for active solar heating systems in cold climates: A case study in Russia 寒冷气候下主动式太阳能供暖系统的技术经济设计框架与分析：以俄罗斯为例

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-04-01 Epub Date: 2026-02-24 DOI: 10.1016/j.applthermaleng.2026.130311

Zahra Pezeshki , Ildar Sultanguzin , Yury V. Yavorovsky , Eugene Krinitsky , Glazov Vasily

In this article, The viability of installing solar heating systems in Russia, in Ashukino, an urban locality (urban-type settlement) in Pushkinsky District of Moscow, is evaluated. Utilizing T*SOL software, the study examined a distinct solar collector system based on SK YaSolar and compared it with Apricus, Eraslan, and Thermital collectors. The SK YaSolar systems were selected based on their size, type of collector (flat plate or evacuated tube), and collector closed loop. Additionally, the effects of changing the hot water storage tank’s dimensions were examined. The goal is to find an techno-economical solution for a logical design that minimizes CO₂ emissions, lowers initial and ongoing costs, and maximizes energy efficiency. According to the analysis findings, for the case study, the electrical energy from solar for heating usage is 1029 kWh, of which 1024 kWh for a 500-liter domestic water tank and 5 kWh for 44-liter buffer tank and heating the space. To achieve long-term operational stability, the operational feasibility using the quantitative and qualitative data outputs of four collector systems, both closed-loop ETC and FPC, was done. Based on analyses, it was discovered that the larger gross surface and aperture area play an important role in meeting increasing energy demand; however, for smaller spaces with smaller water storage tanks, smaller collectors are more suitable, but small tanks, because they have higher standby losses per unit volume and reaches its maximum temperature faster, shutting off the collector, potentially does not allow the tank buffer to heat up and hence collects less solar energy. Based on findings from the geographical sensitivity analysis for various regions with different exposure level of solar radiation received in Russia, it is projected that from 0.002 to 0.069 million Ton of CO₂ emissions can be averted annually. So, solar heating systems provide a cost-effective and environmentally friendly energy solution by doing away with the requirement for an electrical water heater and saving a significant amount of energy.

在这篇文章中，在俄罗斯安装太阳能供暖系统的可行性进行了评估，在阿舒基诺，在莫斯科普希金斯基区的一个城市地区（城市型定居点）。利用T*SOL软件，研究了一种基于SK YaSolar的独特太阳能集热器系统，并将其与Apricus、Eraslan和Thermital集热器进行了比较。SK YaSolar系统是根据其尺寸、集热器类型（平板或真空管）和集热器闭环进行选择的。此外，还考察了改变储热水箱的尺寸对保温效果的影响。我们的目标是找到一种技术经济的解决方案，使逻辑设计最大限度地减少二氧化碳排放，降低初始和持续成本，并最大限度地提高能源效率。根据分析结果，在案例研究中，用于供暖的太阳能电能为1029千瓦时，其中1024千瓦时用于500升的生活水箱，5千瓦时用于44升的缓冲水箱并加热空间。为了实现长期稳定运行，利用闭环ETC和FPC四种集热器系统的定量和定性数据输出进行了运行可行性分析。通过分析发现，更大的总表面积和孔径面积对满足日益增长的能源需求起着重要作用；然而，对于更小的空间和更小的储水箱，更小的集热器更合适，但是小的水箱，因为他们有更高的待机损失每单位体积和达到最高温度更快，关闭集热器，潜在地不允许水箱缓冲加热，因此收集更少的太阳能。根据对俄罗斯接受不同太阳辐射暴露水平的各个地区的地理敏感性分析结果，预计每年可避免0.002至0.069万吨的二氧化碳排放。因此，太阳能供暖系统提供了一种既经济又环保的能源解决方案，因为它不需要电热水器，节省了大量的能源。

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引用次数: 0

Optimization of spiral-baffle thermocline tanks under varying conditions in solar Kalina cycles 太阳能Kalina循环中不同工况下螺旋挡板温跃层储罐的优化设计

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-04-01 Epub Date: 2026-02-23 DOI: 10.1016/j.applthermaleng.2026.130381

Kaiyuan Huang , Junye Hua , Baolian Niu , Gui Li , Xianan Zeng , Xinmin Liu , Hai Lan , Keyi Sang , Huiyan Liu

The Kalina cycle, which is well suited for low- and medium-temperature heat sources, exhibits strong coupling potential with solar thermal power generation systems. Thermocline thermal energy storage tanks, owing to their simple structure and reliable operation, are widely used in solar thermal plants. In this study, a spiral baffle is introduced into an inclined thermocline storage tank with the aim of improving thermal stratification behavior through geometric and operating parameter adjustment. Transient three-dimensional numerical simulations are conducted to investigate the combined effects of height-to-diameter ratio and incline angle, as well as operating conditions including inlet molten salt temperature, on the charging and discharging characteristics. Within the investigated parameter ranges, the results indicate that favourable discharging performance occurs when the inclination angle is between 10° and 20° and the height-to-diameter ratio is between 3.2 and 3.4, with a maximum simulated discharging efficiency of 93.36%. Increasing inlet temperature tends to destabilize the flow field, and relatively better performance is observed within a moderate temperature range. When the inlet temperature is between 473 K and 573 K, the simulated charging and discharging efficiencies reach 93.0% and 92.8%, respectively. In addition, numerical comparison with a conventional storage tank under the same modeling assumptions suggests that the spiral-baffle configuration can shorten the charging and discharging durations by 37.1% and 35.5%, respectively, and increase the discharging efficiency from 88.37% to 90.84%. These findings reflect trends observed within the present numerical framework and parameter space, rather than general optimization results.

Kalina循环非常适合中低温热源，与太阳能热发电系统具有很强的耦合潜力。温跃层蓄热罐由于结构简单、运行可靠，在太阳能热电厂中得到了广泛的应用。本研究在斜斜温跃层储罐中引入螺旋挡板，通过几何和操作参数的调整来改善热分层行为。通过瞬态三维数值模拟研究了高径比、倾斜角以及入口熔盐温度等工况对充放电特性的综合影响。结果表明，在试验参数范围内，当倾角在10°~ 20°之间，高径比在3.2 ~ 3.4之间时，放电效果较好，模拟放电效率最高可达93.36%；提高进口温度会使流场不稳定，在中等温度范围内表现出相对较好的性能。当进口温度为473 ~ 573 K时，模拟的充放电效率分别达到93.0%和92.8%。与传统储罐在相同建模条件下的数值对比表明，采用螺旋挡板结构的储罐，充、放电时间分别缩短37.1%和35.5%，放电效率由88.37%提高到90.84%。这些发现反映了在当前数值框架和参数空间内观察到的趋势，而不是一般的优化结果。

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引用次数: 0

A thermodynamics-based turbocharger matching method for large-displacement methanol engines considering in-cylinder air state and exhaust composition 考虑缸内空气状态和排气成分的大排量甲醇发动机增压器热力学匹配方法

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-04-01 Epub Date: 2026-02-19 DOI: 10.1016/j.applthermaleng.2026.130180

Xianyu Jia , Yongfeng Liu , Lifeng Ma , Qisheng Zhang , Xiqing Zhang

Methanol has attracted increasing attention for internal combustion engines due to its clean combustion characteristics and carbon-neutral potential. Most existing methanol engines are converted from natural gas or diesel engines. However, their performance is constrained by methanol's low heating value and lean-burn characteristics, which demand a larger intake air mass under high-power conditions. This challenge is further complicated by the high water content and relatively low temperature of the exhaust gas, which hinder efficient exhaust energy recovery. Consequently, turbochargers originally matched for fossil-fuel engines often fall short in meeting the needs of methanol engines, making dedicated re-matching of the turbocharging system necessary. In this study, a thermodynamics-based turbocharger matching method is proposed to improve engine performance by accounting for the in-cylinder air state and the effects of exhaust composition, thereby achieving thermodynamic synergistic matching among the engine, compressor, and turbine. The method was validated experimentally across a range of engine speeds and throttle openings, with the deviation between the measured and calculated values remaining within 5%. Finally, a well-matched turbocharger for a 14.5 L methanol engine is selected according to the method, achieving a maximum power of 481.82 kW and a maximum torque of 2880.17 N·m, representing improvements of 23.52% and 9.20%, respectively, compared with the original turbocharger. The proposed method directly determines key turbocharger performance parameters for given engine targets, enabling rapid turbocharger–engine matching and accelerating methanol engine development.

甲醇因其清洁燃烧特性和碳中和潜力而越来越受到内燃机领域的关注。大多数现有的甲醇发动机都是由天然气或柴油发动机改装而来的。然而，它们的性能受到甲醇的低热值和稀燃特性的限制，在大功率条件下需要更大的进气质量。废气的高含水量和相对较低的温度使这一挑战进一步复杂化，这阻碍了有效的废气能量回收。因此，最初用于化石燃料发动机的涡轮增压器往往无法满足甲醇发动机的需求，因此有必要专门重新匹配涡轮增压系统。本研究提出了一种基于热力学的增压器匹配方法，通过考虑缸内空气状态和排气成分的影响来提高发动机性能，从而实现发动机、压气机和涡轮的热力学协同匹配。该方法在发动机转速和油门开度范围内进行了实验验证，测量值与计算值之间的偏差保持在5%以内。最后根据该方法选择了一款匹配良好的14.5 L甲醇发动机涡轮增压器，最大功率为481.82 kW，最大扭矩为2880.17 N·m，比原涡轮增压器分别提高了23.52%和9.20%。该方法直接确定了给定发动机目标的关键涡轮增压器性能参数，实现了涡轮增压器与发动机的快速匹配，加速了甲醇发动机的发展。

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引用次数: 0

Gyroid-based PCM-water compact heat exchangers 基于陀螺的pcm -水紧凑型热交换器

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-04-01 Epub Date: 2026-02-20 DOI: 10.1016/j.applthermaleng.2026.130352

Federico Torri , Fabio Berni , Youssef Aider , Prashant Singh

Triply periodic minimal surface structures are investigated in heat exchanger configuration with phase change material and water as participating media. Gyroid-based monolith heat exchangers are additively manufactured via selective laser melting AlSi10Mg at three different porosities of 0.7, 0.75 and 0.8. Transient heat transfer experiments are conducted for a wide range of water flow rates to understand the effect of porosity and water flow conditions on the phase change material solidification. Besides experimental characterization, a computational fluid dynamics methodology is proposed to investigate the performance of the tested exchangers and is validated against experiments. This study shows that the lowest-porosity structure provides the best thermal performance in terms of total time required for phase change material solidification, with a reduction of nearly 40% compared to the highest porosity one. This performance is the result of higher convective heat transfer coefficient and effective thermal conductivity due to higher metal content. The highest-porosity specimen exhibits greater latent heat storage capability and lower water pressure drop, reducing the required pumping power to 40% of that associated with the lowest porosity structure. The total solidification time is found to be less sensitive to water flow rate for a given Gyroid porosity. In comparison with a conventional offset strip fins topology, the Gyroid structure exhibits higher performance evaluation criterion, thus offering higher global thermo-hydraulic efficiency.

研究了以相变材料和水为参与介质的换热器三周期最小表面结构。采用选择性激光熔化AlSi10Mg，以0.7、0.75和0.8三种不同的孔隙率制备了基于陀螺的整体热交换器。为了解孔隙率和水流条件对相变材料凝固的影响，进行了大范围水流速率下的瞬态传热实验。除了实验表征外，还提出了一种计算流体动力学方法来研究所测试的交换器的性能，并通过实验进行了验证。本研究表明，就相变材料凝固所需的总时间而言，孔隙率最低的组织具有最佳的热性能，与孔隙率最高的组织相比，相变材料凝固所需的总时间减少了近40%。这种性能是由于较高的金属含量而产生较高的对流换热系数和有效导热系数的结果。孔隙度最高的试样具有更大的潜热储存能力和更小的水压降，将所需的泵送功率降低到最低孔隙度结构的40%。发现在给定的旋流孔隙率下，总凝固时间对水流速率不太敏感。与传统的偏置带状翅片拓扑结构相比，该结构具有更高的性能评价标准，从而具有更高的全局热水效率。

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引用次数: 0

Vertical-finned microchannel heat exchangers: Fin geometry effects on thermal–hydraulic performance under dry and frosting conditions 垂直翅片微通道热交换器：翅片几何形状对干燥和结霜条件下热工性能的影响

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-04-01 Epub Date: 2026-03-02 DOI: 10.1016/j.applthermaleng.2026.130473

Yuzhao Luo , Meng Lu , Chen Zheng , Jiedong Ye , Jianxun Huang , Kewei Shi , Feng Li , Bao Yue , Bin Luo

Optimizing fin geometry is crucial for mitigating frost-related degradation of vertical-finned microchannel heat exchangers (VMHXs) in air-source heat pumps, yet trade-offs between dry, frosting, and drainage performance remain unclear. This study experimentally compares wavy/louvered fins (1.3 mm/1.5 mm spacings) under standard dry (35/24 °C) and frosting (2/1 °C) conditions. At Re

\approx

568 (dry), louvered fins enhance Colburn

j

-factor by 54.9% but double the friction factor, with 1.5 mm spacing showing higher thermo-hydraulic efficiency (PEC) than 1.3 mm. Under frosting (484 m³ h⁻¹), louvered fins achieve higher peak heat transfer (520.5 W vs. 500.7 W) but accumulate twice the total frost mass by cycle end, leading to faster performance decay. Wavy fins (1.3 mm) exhibit superior frost resilience, 45% shorter drainage time (107.4 s vs. 195.9 s), and 24% lower water retention. All tested configurations feature a hydrophilic coating and identical core dimensions. A climate-adaptive guideline is proposed: wavy fins (1.3 mm) for high-humidity/frost-prone regions, louvered fins (1.5 mm) for dry climates, and hybrid fins for mixed conditions. This work provides practical insights for optimizing VMHX energy efficiency and operational stability in next-generation HVAC systems.

优化翅片几何形状对于减轻空气源热泵中垂直翅片微通道热交换器（VMHXs）的霜冻相关退化至关重要，但干燥、结霜和排水性能之间的权衡仍不清楚。本研究在标准干燥（35/24°C）和结霜（2/1°C）条件下实验比较波浪/百叶翅片（1.3 mm/1.5 mm间距）。在Re≈568（干）时，百叶翅片使Colburn j系数提高了54.9%，但摩擦系数提高了一倍，1.5 mm间距比1.3 mm间距显示出更高的热压效率（PEC）。在结霜（484 m3 h−1）下，百叶翅片实现更高的峰值换热（520.5 W vs 500.7 W），但在循环结束时累积的霜质量是总霜质量的两倍，导致性能衰减更快。波浪翅片（1.3 mm）具有较好的抗冻性，排水时间缩短45% (107.4 s vs. 195.9 s)，保水率降低24%。所有测试的配置都具有亲水性涂层和相同的芯尺寸。提出了一种气候适应指南：波浪鳍（1.3毫米）适用于高湿度/易霜冻地区，百叶鳍（1.5毫米）适用于干燥气候，混合鳍适用于混合条件。这项工作为优化下一代暖通空调系统的VMHX能源效率和运行稳定性提供了实际见解。

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引用次数: 0

Data-driven multi-fidelity topology design for enhancing the cooling performance of embedded liquid-cooled microchannels 提高嵌入式液冷微通道冷却性能的数据驱动多保真度拓扑设计

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-04-01 Epub Date: 2026-01-26 DOI: 10.1016/j.applthermaleng.2026.129831

Jian Zhang, Pan Cui, Zexin He, Zhichun Liu, Wei Liu

Embedded microchannel heat sinks (MCHS) represent a critical technology for mitigating thermal bottlenecks within chips, and their structural optimization and heat transfer enhancement have become central research themes in this domain. This study applies a data-driven multifidelity topology optimization framework to the design of liquid-cooled microchannels. Compared to existing literature, the latent space dimensionality of the variational autoencoder (VAE) is extended to 64 to capture higher-order topological features; the VAE serves dual functions of cross-fidelity sampling and design space exploration within the framework. Furthermore, a crossover–mutation strategy balancing elitism preservation and diversity enhancement is proposed, which maintains offspring structural diversity. The high-fidelity tier of the multi-fidelity framework employs a realizable k–ε turbulence model, while the low-fidelity tier is based on a pseudo-three-dimensional laminar topology-simplified model. Under identical Reynolds number constraints, the comprehensive performance evaluation coefficient (PEC) of the optimized structure is increased by up to 56% relative to conventional rectangular pin-fin arrays. The findings demonstrate that the data-driven multi-fidelity topology optimization approach holds potential for enhancing flow and heat transfer performance in embedded liquid-cooled microchannel design.

嵌入式微通道散热器（MCHS）是缓解芯片内部热瓶颈的关键技术，其结构优化和传热增强已成为该领域的核心研究课题。本研究将数据驱动的多保真度拓扑优化框架应用于液冷微通道的设计。与现有文献相比，将变分自编码器（VAE）的潜在空间维数扩展到64，以捕获高阶拓扑特征；VAE在框架内具有交叉保真采样和设计空间探索的双重功能。此外，提出了一种平衡精英保留和多样性增强的交叉突变策略，以保持后代的结构多样性。多保真度框架的高保真层采用可实现的k -ε湍流模型，低保真层采用伪三维层流拓扑简化模型。在相同雷诺数约束条件下，优化后的结构的综合性能评价系数（PEC）比传统的矩形翅片阵列提高了56%。研究结果表明，数据驱动的多保真度拓扑优化方法在嵌入式液冷微通道设计中具有提高流动和传热性能的潜力。

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引用次数: 0