Applied Thermal Engineering最新文献_第6页

A coupled thermal-fluid-structure model and performance analysis of twin-screw vacuum pumps under high vacuum conditions 高真空条件下双螺杆真空泵的热流固耦合模型及性能分析

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.applthermaleng.2026.129978

Ruijie Hou , Lifan Xing , Jun Wang , Zengyao Li , Chunji Ren , Zengli Wang , Dong Cui

Twin-screw vacuum pumps (TSVPs) are key components in integrated circuit manufacturing processes that operate under high vacuum conditions. Accurately predicting the performance of TSVPs under rarefied gas and thermal deformation effects remains challenging. To address this challenge, this study proposes a coupled thermal-fluid-structure model that integrates a control chamber model, a rarefied gas leakage model, a thermal network model, and a variable thermal channel model. Unlike conventional approaches based on fixed channel dimensions or isothermal assumptions, the proposed model dynamically accounts for gas rarefaction, suction process, discharge backflow, heat transfer, and thermal deformation. This capability enables accurate performance prediction of TSVPs under both cold and thermal states. Temperature distributions and pumping characteristics of the TSVP were experimentally tested. Based on this model, influences of the inlet pressure, thermal and cold states, and channel dimensions on the thermodynamic characteristics and performance of TSVPs were systematically investigated. Results indicate that, as the inlet pressure decreases, an increasing number of chambers sequentially reach their specific ultimate pressure, from the discharge end to the suction end. Thermal deformation gradients, narrowing leakage channels and under-compression simultaneously occur after long-term operation. The leakage of the flat channel increases from 23% on the discharge side to 79% on the suction side. The leakage of the thin slit channel shows the opposite trend, dropping from 63% to 12%. Thin slit channel dimensions should be reduced in low pressure chambers, while flat plate channel dimensions should be reduced in high pressure chambers to optimize efficiency and power consumption.

双螺杆真空泵（TSVPs）是集成电路制造过程中在高真空条件下运行的关键部件。准确预测TSVPs在稀薄气体和热变形作用下的性能仍然是一个挑战。为了解决这一挑战，本研究提出了一个耦合的热流结构模型，该模型集成了控制室模型、稀薄气体泄漏模型、热网络模型和可变热通道模型。与传统的基于固定通道尺寸或等温假设的方法不同，该模型动态地考虑了气体稀薄、吸入过程、排放回流、传热和热变形。这种能力使tsvp在冷状态和热状态下都能准确地预测性能。实验测试了TSVP的温度分布和泵送特性。在此模型的基础上，系统研究了进口压力、冷热状态、通道尺寸对TSVPs热力学特性和性能的影响。结果表明，随着进口压力的降低，从排出端到吸入端达到特定极限压力的腔室数量依次增加；长期运行后，同时出现热变形梯度、泄漏通道变窄和欠压缩现象。平面通道的泄漏量从排出侧的23%增加到吸力侧的79%。细缝通道的渗漏率则呈现相反的趋势，从63%下降到12%。在低压室应减小细缝通道尺寸，而在高压室应减小平板通道尺寸，以优化效率和功耗。

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引用次数: 0

Dynamic occupancy-aware HVAC control in large office building using enhanced soft actor-critic with PV and thermal energy storage integration 基于光伏和热能存储集成的增强型软评价系统的大型办公大楼动态占用感知HVAC控制

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.applthermaleng.2026.129937

Bilal Ahmed , Ateeque Ahmed , Abdul Mujeeb , Hong-Na Zhang , Xiao-Bin Li , Kai-Yang Qu , Feng-Chen Li

Large office buildings face major challenges due to high energy demand, inefficient heating, ventilation and air conditioning (HVAC) operation, delayed thermal responses and persistent trade-offs between energy cost and thermal comfort. Existing reinforcement learning studies mainly focus on small to medium scale buildings, rely on instantaneous state representations and assume static occupancy based on fixed comfort setpoints. Moreover, the integration of on-site energy systems such as photovoltaic (PV) or thermal energy storage (TES) together with weather forecasts remains limited. To address these gaps, this study develops a deep reinforcement learning-based control framework using the Soft Actor-Critic algorithm to enhance energy flexibility in large office building. The framework introduces a dynamic occupancy-aware comfort strategy that adaptively adjusts indoor temperature bounds based on time-varying occupancy. It integrates PV and TES to enable load shifting and improved renewable energy utilization. Delayed thermal dynamics are addressed by augmenting instantaneous states with historical HVAC actions and zone temperature information, while weather forecasts enable anticipatory control. The framework is evaluated through EnergyPlus-Python co-simulation using real weather and electricity price data for Rome, Italy during summer 2022. Compared with a rule-based control strategy, the proposed approach reduces thermal discomfort by 12.55 h and achieves energy consumption and cost reductions of up to 12.95% and 14.55% over a one-month evaluation period. These results demonstrate the effectiveness of the proposed framework in enabling intelligent, anticipatory HVAC control to enhance energy flexibility and occupant thermal comfort in large office buildings.

由于能源需求高、供暖、通风和空调（HVAC）运行效率低、热响应延迟以及能源成本和热舒适之间的持续权衡，大型办公建筑面临着重大挑战。现有的强化学习研究主要集中在中小型建筑上，依赖于瞬时状态表征，并基于固定的舒适设定值假设静态占用。此外，光伏（PV）或热能储存（TES）等现场能源系统与天气预报的整合仍然有限。为了解决这些差距，本研究开发了一个基于深度强化学习的控制框架，使用软行为者-批评家算法来提高大型办公大楼的能源灵活性。该框架引入了一个动态的占用感知舒适策略，该策略可以根据时间变化的占用情况自适应地调整室内温度界限。它集成了光伏和TES，以实现负荷转移和提高可再生能源的利用率。通过增加历史HVAC动作和区域温度信息的瞬时状态来解决延迟的热动力学问题，而天气预报可以实现预期控制。该框架通过EnergyPlus-Python联合模拟进行评估，使用2022年夏季意大利罗马的真实天气和电价数据。与基于规则的控制策略相比，该方法减少了12.55 h的热不适，在一个月的评估期内，能耗和成本分别降低了12.95%和14.55%。这些结果证明了所提出的框架在实现智能、预期的暖通空调控制方面的有效性，以提高大型办公大楼的能源灵活性和居住者的热舒适性。

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引用次数: 0

Dynamic performance evaluation of coal-fired power units coupled with molten-salt thermal energy storage: a quasi-steady-state approach 结合熔盐储能的燃煤发电机组动态性能评价：准稳态方法

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.applthermaleng.2026.129967

Fengyongkang Wu, Xiang Liu, Jiale Zhang, Huaan Li, Lijia Wei, Yajie Wu, Hao Zhou

High-penetration wind and photovoltaic integration has intensified the need for rapid and deep load regulation from coal-fired power units. Coupling these units with molten-salt thermal energy storage is considered an effective pathway to enhance operational flexibility. However, existing studies predominantly rely on steady-state analyses, which cannot capture the transient coupling among steam extraction, reinjection, and molten-salt charging. To address this methodological gap, this study develops a quasi-steady-state dynamic modeling framework based on MATLAB-Aspen Plus co-simulation. The framework discretizes the entire peak-shaving process into sequential steady-state steps through bidirectional ActiveX data exchange, and incorporates a support vector regression model to predict turbine stage parameters, thereby improving the transient accuracy of the quasi-steady approach. A charging-time-based description of reinjection delay is further proposed to quantify how the extraction-reinjection sequence influences short-term power deviation. Results reveal that transient flow mismatches can induce power oscillations, while applying upper-bound safety constraints effectively suppresses the positive-feedback-driven instability. Systematic evaluation of multiple charging and discharging strategies identifies the optimal combination-reheated-steam extraction paired with reheater-end reinjection-which achieves a maximum round-trip efficiency of 46.35%. The proposed modeling framework provides a practical and engineering-oriented tool for analyzing flexibility retrofits of coal-fired units under high-renewable energy conditions.

高渗透的风能和光伏一体化加剧了对燃煤发电机组快速和深度负荷调节的需求。将这些装置与熔盐热能储存相结合被认为是提高操作灵活性的有效途径。然而，现有的研究主要依赖于稳态分析，无法捕捉汽抽、回注和熔盐充注之间的瞬态耦合。为了解决这一方法上的差距，本研究开发了一个基于MATLAB-Aspen Plus联合仿真的准稳态动态建模框架。该框架通过双向ActiveX数据交换将整个调峰过程离散为连续的稳态步骤，并结合支持向量回归模型预测水轮机级参数，从而提高了准稳态方法的暂态精度。进一步提出了一种基于充电时间的回注延迟描述，以量化提取-回注顺序对短期功率偏差的影响。结果表明，暂态流失配会引起功率振荡，而采用上界安全约束能有效抑制正反馈驱动的不稳定性。通过对多种进料和排放策略的系统评价，确定了再热-蒸汽抽汽与再热器-末端回注相结合的最优组合，最大往返效率为46.35%。所提出的建模框架为分析高可再生能源条件下燃煤机组的柔性改造提供了一个实用的、面向工程的工具。

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引用次数: 0

Numerical study on the effects of furnace flue gas extraction on ultra-low-load combustion characteristics of a 350 MW coal-fired boiler with flue-gas-molten-salt thermal storage system 炉膛烟气抽提对350mw烟气熔盐蓄热系统燃煤锅炉超低负荷燃烧特性影响的数值研究

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.applthermaleng.2026.129984

Bingyi Jiang , Huanbao Fan , Mengxiang Jiang , Hengyi Zhu , Jie Gao , Jingze Yu , Weilai Wang , Longzhou Qi , Tian Qiu , Zhengwei Shi , Da Kang , Hongmin Sun , Qinghua Wang

The growing share of renewable energy highly requires deep peak shaving of coal-fired power units, forcing utility boilers to operate at ultra-low loads. There has been no research on combustion performance at 15% THA (turbine heat acceptance) of a tower boiler. This study explored combustion characteristics of a newly-built 350 MW corner-tangentially coal-fired tower boiler at loads from BMCR (boiler maximum continuous rating) to 15% THA. To further enhance flexibility, that coal-fired power unit will be integrated with a novel molten-salt thermal storage system driven by flue gas extracted from furnace. Thus, the effects of extraction rates were also evaluated. The maximum temperature drops by 121 K as load decreases. The high temperature regions exceeding 1700 K and the diameter of imaginary tangential circles continuously contract. When the load drops to 30% THA and especially 15% THA, the symmetry of temperature and velocity fields are weakened. NO emission increases to 560.05 mg/m³ (O₂ = 6%) at 15% THA load. With flue gas extraction, the tangential annular region of high temperature and velocity expands outward and their distributions gradually deviate unilaterally, increasing the risk of flame and airflow scouring on furnace walls. At 75% and 50% THA, the maximum extraction proportion is 40%. At 30% THA, even 5% will affects combustion behaviors. Finally, specific ranges of heat provided to thermal storage were obtained. This study contributes to the understanding of ultra-low load operation and provides performance evidence for future development of flue-gas thermal storage or potential utilization of flue gas.

可再生能源份额的不断增长对燃煤发电机组的深度调峰提出了很高的要求，迫使公用事业锅炉在超低负荷下运行。目前还没有对塔式锅炉在15%涡轮热接受时的燃烧性能进行研究。研究了新建350mw切角燃煤塔式锅炉在BMCR（锅炉最大连续额定值）至15%负荷下的燃烧特性。为了进一步提高灵活性，该燃煤发电机组将与一种新型的熔盐储热系统集成，该系统由炉中提取的烟气驱动。因此，也评价了提取率的影响。随着负载的减小，最高温度下降了12k。超过1700 K的高温区域和虚切圆直径不断收缩。当载荷降至30%，特别是15%时，温度场和速度场的对称性减弱。在15% THA负荷下，NO排放量增加到560.05 mg/m3 （O2 = 6%）。随着烟气抽提，高温高速切向环形区域向外扩展，其分布逐渐单边偏离，增加了火焰和气流冲刷炉壁的风险。在75% THA和50% THA时，最大萃取比例为40%。在30% THA时，即使5%也会影响燃烧行为。最后，得到了提供给蓄热器的具体热量范围。该研究有助于对超低负荷运行的理解，并为未来的烟气蓄热开发或烟气的潜在利用提供性能依据。

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引用次数: 0

Development of delayed neutron precursor and decay heat models for molten salt reactors using runge–kutta discontinuous Galerkin methods 用龙格-库塔不连续伽辽金方法建立熔盐堆延迟中子前驱体和衰变热模型

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.applthermaleng.2026.129983

Liaojie Deng , Dalin Zhang , Xinyu Li , Yiwen Chen , Lei Zhou , Wenxi Tian , Suizheng Qiu , Guanghui Su

Molten salt reactors, characterized by circulating liquid fuel, exhibit neutronic and thermal–hydraulic behaviors that differ fundamentally from those of solid-fueled reactors. Accurately modeling the convection-driven transport of delayed neutron precursors and its impact on reactor reactivity remains a challenge for system-level analysis codes. Capturing the spatial distribution of decay heat in the primary loop is another key challenge. To overcome these limitations, a high-fidelity kinetics analysis module is developed based on the Reactor Excursion and Leak Analysis Program (RELAP5/MOD3.2) code. The one-dimensional delayed neutron precursor transport equation is solved using a third-order Runge–Kutta discontinuous Galerkin method, which effectively reduces numerical diffusion and improves spatial resolution in convection-dominated problems. In addition, a simplified decay heat model is established to compute the decay power distribution within the primary loop and is solved consistently with the delayed neutron precursor equation. The developed code is validated against startup, coastdown, and reactivity insertion experiments from the Molten Salt Reactor Experiment. The results show good agreement with experimental measurements and accurately predict delayed neutron precursor migration and transient power behavior. Further analysis of the Molten Salt Breeding Reactor based on the validated model indicates weak negative feedback and high sensitivity to flow perturbations. Under an unprotected loss of heat sink accident, the reactor shows a slow shutdown response. These results demonstrate that the proposed approach provides a reliable tool for the safety analysis of molten salt reactors.

熔盐反应堆的特点是循环液体燃料，表现出与固体燃料反应堆根本不同的中子和热工行为。准确模拟延迟中子前体的对流驱动输运及其对反应堆反应性的影响仍然是系统级分析代码的一个挑战。捕获主回路中衰变热的空间分布是另一个关键挑战。为了克服这些限制，基于反应器偏移和泄漏分析程序（RELAP5/MOD3.2）代码开发了高保真动力学分析模块。采用三阶龙格-库塔不连续伽辽金方法求解一维延迟中子前驱体输运方程，有效地减少了数值扩散，提高了对流占优问题的空间分辨率。此外，建立了简化的衰变热模型，计算了主回路内的衰变功率分布，并与延迟中子前体方程进行了一致的求解。所开发的代码通过熔盐堆实验的启动、滑行和反应性插入实验进行了验证。计算结果与实验结果吻合较好，能准确预测中子前体延迟迁移和瞬态功率行为。基于验证模型的熔盐增殖堆进一步分析表明，该模型的负反馈较弱，对流动扰动具有较高的敏感性。在无保护的热沉损失事故下，反应堆表现出缓慢的关闭反应。结果表明，该方法为熔盐堆的安全性分析提供了可靠的工具。

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引用次数: 0

Pilot-scale fluidized melting combustion of coal gasification slag with a novel combustion organization 新型燃烧组织的煤气化渣流态化熔融燃烧中试研究

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.applthermaleng.2026.129986

Neng Fang , Shuai Guo , Yingjie Wang , Chen Liang , Zhiyong Chen , Shaobo Yang , Wei Li , Yunlei Cui , Qiangqiang Ren

The resource utilization of coal gasification slag presents a bottleneck issue in the green recycling of coal. Traditional combustion technologies struggle to maintain stable combustion, and conventional combustion organization (downstream mode) results in high pollution and carbon emissions. A novel combustion organization of staged air distribution coupled with a reverse flow mode of flue gas and molten slag is proposed. However, the combustion characteristics and the intrinsic emission behaviors of nitrogen and sulfur pollutants, remain unclear. Resolving this challenge will provide valuable insights for the development of high-temperature thermal conversion technologies for flame-retardant fuels. In this study, a kiloton-per-year pilot-scale fluidized melting combustion test was conducted using coal gasification slag from a Texaco entrained-flow gasifier, with the burnout air ratio (λ_b) set at 0, 0.17, and 0.31 as the variable parameter. Experimental results indicate that the fluidized melting combustion system operates stably and enables continuous molten slag discharge. The carbon content of the molten slag is found to be less than 1.5%, while that of the fly ash is approximately 7%. As the burnout air ratio increases, the conversion rate of fuel sulfur to fly ash decreases, whereas the proportion released into the gas phase rises. Additionally, the proportion of fuel nitrogen oxidized to NO_x decreases significantly from 25.4% to 7.3%. Notably, when λ_b is 0.17, the slag capture rate and combustion efficiency reach their maximum values of 87.6% and 98.0%, respectively. Under the identical burnout air ratio, the NO emission of the novel combustion organization is 66%–75% of that in the conventional downstream mode, thus broadening the technical pathways for efficient slag capture and denitrification.

煤气化渣资源化利用是煤炭绿色循环利用的瓶颈问题。传统的燃烧技术很难保持稳定的燃烧，传统的燃烧组织（下游模式）导致高污染和碳排放。提出了一种烟气与熔渣反向流动相结合的新型分级配风燃烧组织。然而，氮和硫污染物的燃烧特性和本征排放行为尚不清楚。解决这一挑战将为阻燃燃料的高温热转化技术的发展提供有价值的见解。本研究以德士古夹带流气化炉的煤气化渣为原料，将燃尽空气比（λb）分别设置为0、0.17和0.31，进行了千吨/年的中试流化熔融燃烧试验。实验结果表明，流态化熔融燃烧系统运行稳定，熔渣连续排出。熔渣含碳量小于1.5%，粉煤灰含碳量约为7%。随着燃尽空气比的增加，燃料硫与飞灰的转化率降低，而释放到气相的比例上升。此外，燃料氮氧化为NOx的比例从25.4%显著下降到7.3%。当λb = 0.17时，捕渣率和燃烧效率分别达到最大值87.6%和98.0%。在相同燃尽空气比下，新型燃烧组织的NO排放量是传统下游模式的66%-75%，从而拓宽了高效捕渣脱硝的技术途径。

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引用次数: 0

Thermodynamic and initial investment analysis of a novel double-helix borehole heat exchanger wrapped with shape-stabilized phase change material 形状稳定相变材料包裹的新型双螺旋钻孔换热器热力学及初始投资分析

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.applthermaleng.2026.129976

Zhuo Zhou , Yong Wang , Yao Tao , Zhenguo Lin , Gang Wu , Chunyi Yu , Weilan Wu

The integration of advanced geometries with phase change materials (PCMs) offers a promising pathway to enhance borehole heat exchanger (BHE) performance, yet a comprehensive evaluation combining thermodynamic and economic perspectives is lacking. To bridge this gap, this study proposes a novel double-helix BHE wrapped with shape-stable PCM (SSPCM). A three-dimensional transient numerical model was developed and experimentally validated. A comprehensive comparison assessed the thermo-hydraulic performance, thermodynamic irreversibility, and economic feasibility of the proposed design against conventional U-tube, SSPCM-enhanced U-tube, and single-helix configurations. Results show that the double-helix SSPCM design improves the heat exchange rate per unit depth by 80–99% while effectively reducing local entropy generation near the pipe wall. Entropy analysis reveals the trade-off between diminished local irreversibility (due to enhanced heat extraction) and increased total system entropy. Although the initial investment rises by approximately 72.5%, the double-helix BHE demonstrates excellent cost-effectiveness owing to its significantly higher specific performance, which can reduce the required drilling depth. This work is the first to holistically evaluate a double-helix SSPCM-BHE through integrated 3D CFD simulation, second-law thermodynamic analysis, and economic assessment, establishing valuable benchmarks for designing high-performance and sustainable shallow geothermal systems.

将先进的几何形状与相变材料（pcm）相结合，为提高井下热交换器（BHE）的性能提供了一条有希望的途径，但目前还缺乏结合热力学和经济角度的综合评估。为了弥补这一差距，本研究提出了一种新的双螺旋BHE包裹形状稳定的PCM （SSPCM）。建立了三维瞬态数值模型，并进行了实验验证。综合比较了该设计与传统u型管、sscm增强型u型管和单螺旋结构的热水力性能、热力学不可逆性和经济可行性。结果表明，双螺旋SSPCM设计可将单位深度换热率提高80-99%，同时有效减少管壁附近的局部熵产。熵分析揭示了局部不可逆性减少（由于热量提取增强）和系统总熵增加之间的权衡。虽然初始投资增加了约72.5%，但双螺旋BHE由于具有更高的比性能，可以降低所需的钻井深度，因此具有出色的成本效益。这项工作首次通过集成的3D CFD模拟、第二定律热力学分析和经济评估对双螺旋SSPCM-BHE进行了全面评估，为设计高性能和可持续的浅层地热系统建立了有价值的基准。

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引用次数: 0

An experimental investigation on hydraulic and thermal performance of SLM-printed Mini channels using different printing parameters 采用不同的打印参数对slm打印的微型通道的水力和热性能进行了实验研究

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-26 DOI: 10.1016/j.applthermaleng.2026.129914

Jia Hang Chen , Yi Fan Yang , Lap Mou Tam , Afshin J. Ghajar

Additive manufacturing (AM), particularly selective laser melting (SLM), has brought revolutionary degrees of freedom to the design of compact heat exchangers. The previous studies on pressure drop and heat transfer characteristics of AM heat exchangers primarily concentrated on numerical simulation, with surface morphology and porosity conditions typically based on idealized assumptions. However, variations in empirical printing parameters among different AM manufacturers lead to unignorable differences in the hydraulic and thermal performance of the SLM-printed heat exchangers with the same geometric structure. This study experimentally investigates the pressure drop and heat transfer characteristics of circular SLM-printed horizontal mini channels fabricated by three different sets of printing parameters commonly used by AM manufacturers. Additionally, the experimental results were also compared with the pressure drop and heat transfer data of traditional cold-rolled stainless steel tubes. The experimental results demonstrate that the different combination of printing parameters (such as laser power, layer thickness, laser spot, etc.) results in notable differences in surface roughness and internal porosity of the printed samples, which directly affects the hydraulic and thermal performance. The SLM-printed channel with the best performance showed a 30.62% improvement in the efficiency index

(\frac{j}{j_{p}} / \frac{f}{f_{p}})

compared to the channel with the worst performance across the entire flow regime. Hence, the findings of this study not only reveal that the selection of printing parameters had a significant effect on hydraulic and thermal performance but also provide a reference for thermal engineers in designing and developing SLM-printed heat exchangers and thermal management devices.

增材制造（AM），特别是选择性激光熔化（SLM），为紧凑型热交换器的设计带来了革命性的自由度。以往对增材制造换热器压降和换热特性的研究主要集中在数值模拟上，表面形貌和孔隙条件通常基于理想化的假设。然而，不同AM制造商的经验打印参数的差异导致相同几何结构的slm打印热交换器的水力和热性能存在不可忽视的差异。本研究通过实验研究了三种常用的增材制造厂商的打印参数制备的圆形slm打印水平微型通道的压降和传热特性。此外，还将实验结果与传统冷轧不锈钢管的压降和传热数据进行了比较。实验结果表明，不同的打印参数组合（如激光功率、层厚、激光光斑等）会导致打印样品的表面粗糙度和内部孔隙率存在显著差异，从而直接影响其水力和热性能。在整个流态中，性能最好的slm打印通道的效率指数jjp/ffp比性能最差的通道提高了30.62%。因此，本研究结果不仅揭示了打印参数的选择对液力和热性能的显著影响，而且为热工程师设计和开发slm打印换热器和热管理装置提供了参考。

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引用次数: 0

Genetic algorithms and Pearson correlation analysis synergy optimizes thermodynamic performance in multi-dephlegmation auto-cascade refrigeration cycle 遗传算法和Pearson相关分析协同优化了多重脱痰自级联制冷循环的热力学性能

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-25 DOI: 10.1016/j.applthermaleng.2026.129944

Xiuzhen Li, Sen Chen, Ziyun Song, Yingying Tan, Weixuan Niu, Xiwen Zhou, Lin Wang

To address the limitations of traditional auto-cascade refrigeration cycles (TACR) regarding low-temperature efficiency and refrigeration temperature limits, this study proposes a two-stage dephlegmation auto-cascade refrigeration cycle (TDACR), which enhances the purity of low-boiling-point composition by utilizing multi-temperature-level cooling capacities. A thermodynamic mathematical model has been developed using R1150/R600a as the refrigerant. The impact of various operating parameters, including the composition ratio, compression ratio, and dephlegmation temperature, on the thermodynamic performance of the cycle has been analyzed using the controlled variable method. A genetic algorithm is employed for global optimization, and Pearson correlation coefficients are used to evaluate parameter interactions. The results indicate that the TDACR increases the R1150 mass fraction in the evaporator refrigerant by 33.65%. Additionally, the R1150 mass fraction in the evaporator refrigerant exhibits a strongly positive correlation with the coefficient of performance (COP) at 0.77. When the condensation temperature ranges from 30 °C to 40 °C, the refrigeration capacity of the TDACR increases by 7.37%–28.68% compared to the TACR. Furthermore, at evaporation temperatures ranging from −70 °C to −90 °C, the COP of the TDACR improves by 54.55%–258.73% relative to the TACR.

为了解决传统自串级制冷循环（TACR）在低温效率和制冷温度限制方面的局限性，本研究提出了一种两级除湿自串级制冷循环（TDACR），该循环利用多温度级别的冷却能力来提高低沸点组分的纯度。建立了以R1150/R600a为制冷剂的热力学数学模型。采用控制变量法分析了组分比、压缩比、脱痰温度等操作参数对循环热力学性能的影响。采用遗传算法进行全局优化，采用Pearson相关系数评价参数间的相互作用。结果表明，TDACR使蒸发器制冷剂中的R1150质量分数提高了33.65%。此外，蒸发器制冷剂中的R1150质量分数与性能系数（COP）呈强正相关，为0.77。当冷凝温度为30℃~ 40℃时，TDACR制冷量较TACR提高7.37% ~ 28.68%。在−70℃~−90℃的蒸发温度范围内，TDACR的COP比TACR提高了54.55% ~ 258.73%。

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引用次数: 0

Bio-inspired heat exchanger fabricated using additive manufacturing: Numerical and experimental investigation 利用增材制造制造生物热交换器：数值和实验研究

IF 6.9 2区工程技术 Q2 ENERGY & FUELS

Applied Thermal Engineering

Pub Date : 2026-01-25 DOI: 10.1016/j.applthermaleng.2026.129968

Yasser Aljuhani, Ahmet Guner, Adel Abdelwahab, Khamis Essa

Bio-inspired heat exchange architectures translate natural branching logics into engineered flow networks that intensify mixing while maintaining compactness. This study presents develop and validate a vascular-inspired air side heat exchanger fabricated in AlSi10Mg by laser powder bed fusion (LPBF). A structured design of experiments (DoE) explores four geometric controls tube diameter (d), branch angle (θ), height (l), and wall thickness (t) to quantify their effects on the air side heat transfer coefficient and pressure drop. Steady conjugate CFD is coupled with a user-defined function that imposes the measured ±5 °C inlet temperature variability, and results are benchmarked against experimental work over

\dot{m_{a}}

= 0.002–0.040 kg/s. The DoE indicates that dimeter, thickness, and angle are the principal determinants of air side heat transfer coefficient , whereas dimeter and height dominate pressure drop, with significant (l × d), (d × θ), and (d × t) interactions shaping response surfaces. Measurements show heat transfer coefficient increasing monotonically from around 30 to 220 W/m²·K, over 0.002–0.010 kg/s. These results demonstrate that hierarchical branching can enhance air side heat transfer performance with an inevitable hydraulic penalty, positioning LPBF enabled bio-inspired designs as promising candidates for compact thermal management applications where the thermo–hydraulic trade-off can be quantified and managed.

以生物为灵感的热交换架构将自然分支逻辑转化为工程流动网络，在保持紧凑性的同时加强混合。本研究提出并验证了一种用激光粉末床熔合（LPBF）制备AlSi10Mg材料的血管式空气侧热交换器。实验的结构设计（DoE）探索了四种几何控制管径(d)、分支角（θ）、高度(l)和壁厚(t)，以量化它们对空气侧传热系数和压降的影响。稳态共轭CFD与用户定义的函数相结合，该函数施加测量的±5°C入口温度变化，结果与实验工作的基准相匹配，误差为0.002-0.040 kg/s。DoE表明，直径、厚度和角度是空气侧换热系数的主要决定因素，而直径和高度则是压降的主要决定因素，并具有显著的（l × d）、（d × θ）和（d × t）相互作用，形成响应面。测量结果表明，传热系数在0.002-0.010 kg/s范围内从30 W/m2·K单调增加到220 W/m2·K。这些结果表明，分层分支可以在不可避免的水力损失的情况下提高空气侧传热性能，使LPBF生物启发设计成为紧凑型热管理应用的有希望的候选者，在这种应用中，热-水力权衡可以量化和管理。

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引用次数: 0