Measurement: Energy最新文献

Oxygen enrichment studies in hydrogen-natural gas burner: A pilot-scale study on emissions and thermal performance 氢-天然气燃烧器的富氧研究：排放物和热性能的中试研究

Measurement: Energy

Pub Date : 2026-01-02 DOI: 10.1016/j.meaene.2026.100085

Nidhin Thekkedath Madhu , Martin Adendorff , Kristina Mabic , Esin Iplik , Sven Eckart , Hartmut Krause

Decarbonising high-temperature industrial furnaces requires efficient and low-emission combustion strategies. Hydrogen and oxygen enhanced combustion (OEC) are promising alternatives to conventional air-fuel systems, but their combined impact on heat transfer, efficiency, and NOx emissions under practical operating conditions remains underexplored. This study explores the combustion behaviour of a commercial 200 kW burner operating with hydrogen, natural gas, and their blend under varying oxidizer oxygen concentrations, ranging from air-fuel combustion (21 % O₂) to pure oxyfuel combustion (100 % O₂). Conducted at pilot-scale, the research aims to understand how fuel composition and oxygen enrichment influence NOx emissions, heat transfer, wall temperature distribution, and flue gas energy losses. The results reveal that oxygen enrichment plays a dominant role in shaping combustion performance, while the choice of fuel (whether hydrogen, natural gas, or a blend) has a comparatively minor effect. Oxygen enrichment significantly improved heat transfer and reduced flue gas losses, resulting in thermal efficiency increase from ∼45 % in air-fuel to ∼80 % in oxyfuel combustion. Burner configuration such as delayed combustion and flameless combustion strongly influenced temperature uniformity and NOx emissions, where flameless configuration resulted in enhanced mixing, reduced thermal stratification and lower NOx compared to simple delayed combustion. Under delayed and flameless oxyfuel conditions, NOx emissions dropped below 2 mg/MJ for both fuels. With this study, a reduction of ∼90 % in NOx emission while moving from air-fuel to oxyfuel condition was observed for natural gas and hydrogen. Interestingly, at flameless combustion operation, hydrogen showed lower NOx emission than natural gas. Constant-temperature studies confirmed that nitrogen availability, rather than flame temperature, dominated NOx formation under flameless conditions. These findings highlight the potential of oxyfuel and OEC to deliver cleaner and more energy-efficient operation in industrial furnaces, regardless of fuel composition. The insights gained are particularly relevant for industries transitioning toward hydrogen-based energy systems and seeking to meet decarbonisation, NOx emission and efficiency targets.

高温工业炉脱碳需要高效、低排放的燃烧策略。氢和氧增强燃烧（OEC）是传统空气燃料系统的有前途的替代品，但在实际操作条件下，它们对传热、效率和氮氧化物排放的综合影响仍未得到充分研究。本研究探讨了商用200千瓦燃烧器在不同氧化氧浓度下的燃烧行为，从空气燃料燃烧（21% O2）到纯氧燃料燃烧（100% O2）。该研究在中试规模进行，旨在了解燃料成分和氧富集如何影响NOx排放、传热、壁面温度分布和烟气能量损失。结果表明，氧富集在塑造燃烧性能方面起着主导作用，而燃料的选择（无论是氢气、天然气还是混合燃料）的影响相对较小。富氧显著改善了传热并减少了烟气损失，使空气燃料燃烧的热效率从45%提高到80%。延迟燃烧和无焰燃烧等燃烧器配置强烈影响温度均匀性和氮氧化物排放，与简单的延迟燃烧相比，无焰配置增强了混合，减少了热分层，降低了氮氧化物。在延迟和无焰氧燃料条件下，两种燃料的NOx排放量均降至2 mg/MJ以下。在这项研究中，观察到天然气和氢气从空气燃料转变为氧燃料状态时，NOx排放量减少了约90%。有趣的是，在无焰燃烧操作下，氢气的NOx排放量低于天然气。恒温研究证实，在无焰条件下，氮气的可用性，而不是火焰温度，主导了NOx的形成。这些发现突出了含氧燃料和OEC在工业炉中提供更清洁、更节能运行的潜力，无论燃料成分如何。所获得的见解对于向氢基能源系统过渡并寻求实现脱碳、氮氧化物排放和效率目标的行业尤为重要。

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引用次数: 0

Near-nozzle atomization characteristics of GTL-Jet A-1 fuel blends at combustor relevant conditions using shadowgraph measurements GTL-Jet A-1混合燃料在燃烧室相关条件下的近喷嘴雾化特性

Measurement: Energy

Pub Date : 2025-12-26 DOI: 10.1016/j.meaene.2025.100084

Kumaran Kannaiyan

To achieve the goal of sustainable aviation, the aviation industry is considering blends of conventional and alternative jet fuels to achieve clean combustion. To this end, it is essential to understand the atomization characteristics of jet fuel blends better to gain additional insights into their ignition and combustion phenomena. Thus, this study explores the atomization characteristics of alternative-conventional jet fuel blends, i.e., blends of jet fuel derived from natural gas (Gas-To-Liquid, GTL) with Jet A-1 fuels at varying proportions (0, 50 %, 75%, and 100%) under non-reacting conditions at elevated ambient pressures (100 and 500 kPa) and ambient temperatures (300 and 350 K). Towards this goal, a simplex atomizer is used to experimentally investigate the macroscopic atomization characteristics, such as spray cone angle, sheet dynamics and breakup distance, and axial velocity variation at two pressure differentials across the atomizer (300 and 900 kPa). The results demonstrate that the influence of elevated ambient temperature has a stronger correlation with the near-nozzle atomization characteristics. For the type of nozzle studied, the far-field cone angle of jet fuel blends decreased from 70 ° to 60 ° with the increase in ambient gas pressure from 100 to 500 kPa. Under the conditions studied, the blend of 50% GTL-50%Jet A-1 exhibited an earlier onset of liquid-sheet instability, characterized using the second-order statistical moment, when compared to GTL and Jet A-1 fuels. Furthermore, the 50% GTL-50%Jet A-1 blend exhibited shorter liquid-sheet breakup distance than that of 75% GTL-25%Jet A-1 blend. The results presented here will assist in gaining additional insights into their ignition and combustion performance at relevant conditions.

为了实现可持续航空的目标，航空业正在考虑将传统和替代喷气燃料混合使用，以实现清洁燃烧。为此，有必要更好地了解喷气燃料混合物的雾化特性，以获得对其点火和燃烧现象的额外见解。因此，本研究探索了替代传统喷气燃料混合物的雾化特性，即在非反应条件下，在升高的环境压力（100和500 kPa）和环境温度（300和350 K）下，以不同比例（0、50%、75%和100%）从天然气中提取的喷气燃料（气转液，GTL）与jet A-1燃料的混合物。为此，利用单形雾化器实验研究了雾化器两端压差（300和900 kPa）下的宏观雾化特性，如喷雾锥角、片材动力学和破碎距离以及轴向速度变化。结果表明，环境温度升高对近喷嘴雾化特性的影响有较强的相关性。对于所研究的喷嘴类型，随着环境气体压力从100 kPa增加到500 kPa，喷气燃料混合物的远场锥角从70°减小到60°。在研究条件下，与GTL和Jet A-1燃料相比，50% GTL-50%Jet A-1的混合物表现出更早的液片不稳定性，并使用二阶统计矩进行表征。此外，50% GTL-50%Jet A-1共混物比75% GTL-25%Jet A-1共混物的液-片破碎距离更短。这里提出的结果将有助于获得更多的见解，他们的点火和燃烧性能在相关条件下。

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引用次数: 0

Heat transfer and emission characteristics of hydrogen-enriched natural gas in flameless air/oxyfuel combustion in a semi-industrial furnace 富氢天然气在半工业炉无焰空气/富氧燃烧中的传热与排放特性

Measurement: Energy

Pub Date : 2025-12-10 DOI: 10.1016/j.meaene.2025.100083

Kristina Mabic , Martin Adendorff , Nidhin Thekkedath Madhu , Esin Iplik , Tomas Ekman , Ioanna Aslanidou , Konstantinos Kyprianidis

Hydrogen combustion is seen as a promising carbon-free alternative for generating process heat in industrial processes requiring high temperatures and large amounts of energy, such as metal melting and reheating. The transition from natural gas to hydrogen in high-temperature furnaces raises concerns about heat transfer efficiency due to the altered flue gas composition. This study examines the influence of hydrogen enrichment of natural gas on thermal performance and emissions in a semi-industrial box furnace equipped with a flameless burner operating in oxyfuel and air-fuel modes at 200 kW. The burner is primarily designed for the aluminum industry, where oxyfuel mode is used for rapid melting and air-fuel mode during holding periods. Seven different NG/H₂ fuel cases, ranging from natural gas to pure hydrogen, in both burner configurations, are compared experimentally in terms of temperature and energy distribution, gas emissivity, radiative heat flux, and NOx emissions. Additional heating trials on aluminum with hydrogen and natural gas are conducted to quantify the radiative and convective contributions using a combined experimental and numerical approach. Results show that under oxyfuel conditions, hydrogen addition has minimal impact on furnace temperature, flue gas losses, and radiative heat flux. In contrast, air-fuel operation exhibited continuous temperature rise and radiative heat flux, along with reduced flue gas losses. NOx emissions remained below 5 mg/MJ for oxyfuel and 12 mg/MJ for air-fuel combustion, with pure hydrogen achieving lower values than natural gas due to the elimination of prompt NOx. Aluminum heating trials revealed a 6 % improvement in heat flux with hydrogen under oxyfuel and 19 % under air-fuel conditions. These findings confirm that hydrogen can be effectively integrated into flameless combustion without compromising combustion performance, with oxyfuel technology offering greater potential for efficiency gains and NOx mitigation.

氢燃烧被视为在需要高温和大量能源的工业过程中产生过程热的一种有前途的无碳替代方案，例如金属熔化和再加热。高温炉中从天然气到氢气的转变引起了人们对传热效率的关注，因为烟气成分发生了变化。本研究考察了天然气富氢对半工业箱式炉热力性能和排放的影响，箱式炉配有无焰燃烧器，在200千瓦的氧燃料和空气燃料模式下运行。燃烧器主要是为铝工业设计的，其中氧燃料模式用于快速熔化，空气燃料模式用于保温期间。从天然气到纯氢，在两种燃烧器配置下，对7种不同的NG/H2燃料进行了温度和能量分布、气体发射率、辐射热通量和NOx排放的实验比较。采用实验和数值相结合的方法，对铝进行了氢和天然气加热试验，以量化辐射和对流的贡献。结果表明，在含氧燃料条件下，加氢对炉温、烟气损失和辐射热流密度的影响最小。相比之下，空气燃料运行表现出持续的温度上升和辐射热流密度，同时减少了烟气损失。氧燃料的氮氧化物排放量保持在5 mg/MJ以下，空气燃料燃烧的氮氧化物排放量保持在12 mg/MJ以下，由于消除了迅速产生的氮氧化物，纯氢的数值低于天然气。铝加热试验表明，氢在氧燃料条件下的热流密度提高了6%，在空气燃料条件下的热流密度提高了19%。这些发现证实，氢可以有效地整合到无焰燃烧中，而不会影响燃烧性能，含氧燃料技术提供了更大的效率提升和减少氮氧化物的潜力。

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引用次数: 0

Optimized SVM and feature selection for fault detection and classification in GFM-IBR system 优化支持向量机和特征选择在ggm - ibr系统故障检测与分类中的应用

Measurement: Energy

Pub Date : 2025-11-27 DOI: 10.1016/j.meaene.2025.100081

Armin Ahmadi Bouzandani , Behrooz Taheri , Seyed Amir Hosseini

Due to the increasing integration of new energy sources and the critical need for power grid stability, accurate fault detection and classification in power systems has become paramount. Therefore, this paper presents a new, optimized framework for fault detection in Grid-Forming Inverter-Based Resource (GFM-IBR) power systems. This framework is based on frequency feature extraction using the Fast Fourier Transform (FFT) and a Support Vector Machine (SVM) model. First, we sample the voltage and current signals from the IBR side. Then, the angle and phase values of these signals are extracted using FFT. The average angle and phase values obtained within the 10-ms period after a fault in each phase are then designated as the main features. The distinctive aspect of this study is its dual optimization approach. This involves both adjusting the parameters of the SVM model and optimally selecting features using several evolutionary and metaheuristic algorithms, specifically HHO, PSO, GA, GWO, WOA, GOA, DO, and AEO. The method presented in this paper was tested on a power system connected to a GFM-IBR, simulated in PSCAD software. The data generated in PSCAD was then transferred to a Google Colab environment for feature extraction and SVM model training.

随着新能源集成度的不断提高和对电网稳定性的迫切需求，电力系统的准确故障检测和分类变得至关重要。因此，本文提出了一种新的、优化的基于并网逆变器资源（ggm - ibr）电力系统故障检测框架。该框架基于使用快速傅里叶变换（FFT）和支持向量机（SVM）模型的频率特征提取。首先，我们对IBR侧的电压和电流信号进行采样。然后，利用FFT提取这些信号的角度和相位值。然后将故障发生后10毫秒内的平均角度和相位值作为主要特征。本研究的独特之处在于其双重优化方法。这既包括调整SVM模型的参数，也包括使用几种进化和元启发式算法（特别是HHO、PSO、GA、GWO、WOA、GOA、DO和AEO）优化选择特征。本文所提出的方法在一个与ggm - ibr相连的电力系统上进行了测试，并在PSCAD软件中进行了仿真。然后将PSCAD生成的数据传输到谷歌Colab环境中进行特征提取和SVM模型训练。

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引用次数: 0

Evaluation of the efficiency of a low voltage autotransformer 一种低压自耦变压器的效率评价

Measurement: Energy

Pub Date : 2025-11-26 DOI: 10.1016/j.meaene.2025.100080

Edwin Garabitos-Lara , José Miguel Mateo-Beltré , Jesús Manuel Silva-García

In many developing countries, low-voltage autotransformers are commonly used in residential settings to compensate for persistent voltage irregularities in the electrical distribution network. Despite their widespread use, few studies have systematically evaluated their performance and efficiency under typical operating conditions. This study presents the design, construction, and experimental evaluation of a low-voltage autotransformer rated at 1580 VA. The design equations were derived from Faraday's Law, and the equivalent circuit parameters were obtained through open-circuit and short-circuit tests. The efficiency was measured using a power network analyzer under resistive and non-resistive loads and compared with values calculated analytically from the equivalent circuit. The study also incorporated uncertainty analysis in both experimental and analytical procedures. Results showed that the autotransformer reached an efficiency of 98.0 % under nominal load and exceeded 90.0 % efficiency at just 10.7 % of the demand coefficient. Furthermore, the all-day efficiency remained stable between 96.5 % and 96.8 % across real residential demand profiles, confirming consistent energy performance under variable load conditions. The differences between measured and calculated efficiencies were below 1 percentage point in all cases, and validation was confirmed using uncertainty propagation, mean absolute error (MAE), and root mean square error (RMSE). These findings reinforce the reliability of the analytical model and highlight the high efficiency of these devices as voltage-regulating elements when properly designed.

在许多发展中国家，低压自耦变压器通常用于住宅环境，以补偿配电网络中持续的电压不正常。尽管它们被广泛使用，但很少有研究系统地评估它们在典型操作条件下的性能和效率。本文介绍了一种额定电压为1580 VA的低压自耦变压器的设计、构造和实验评估，根据法拉第定律推导了设计方程，并通过开路和短路试验获得了等效电路参数。利用电网分析仪在电阻性和非电阻性负载下测量了效率，并与等效电路的解析计算值进行了比较。该研究还在实验和分析过程中纳入了不确定度分析。结果表明，自耦变压器在额定负载下效率达到98.0%，在需求系数仅为10.7%时效率超过90%。此外，在实际住宅需求曲线中，全天效率保持稳定在96.5%至96.8%之间，确认了在可变负载条件下的一致能源性能。在所有情况下，测量和计算效率之间的差异都低于1个百分点，并且使用不确定性传播、平均绝对误差（MAE）和均方根误差（RMSE）来确认有效性。这些发现加强了分析模型的可靠性，并突出了这些器件在适当设计时作为电压调节元件的高效率。

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引用次数: 0

A dimensionless criterion system for energy efficiency evaluation in steel rolling reheating furnaces 轧钢加热炉能效评价的无量纲标准体系

Measurement: Energy

Pub Date : 2025-11-26 DOI: 10.1016/j.meaene.2025.100078

Yi Duan, Guang Chen, Xiangjun Bao, Lu Zhang, Xiaojing Yang

As a key high-energy-consuming equipment in steel production, the energy efficiency optimization of steel rolling reheating furnaces (SRRF) has long been constrained by three core contradictions: "energy consumption-temperature matching, rolling rhythm-quality coordination, and billet shape-energy efficiency differentiation". In this study, a "general-subdivision" two-layer criterion system is established. The general criterion (N_E) quantifies global energy consumption redundancy by means of the ratio of actual energy consumption to theoretical heat demand. The shape-corrected criterion (N_{E, M}), meanwhile, incorporates a correction term for the width-to-thickness ratio (W/H) to distinguish between shape-induced inherent losses and operationally controllable losses. Verification using 1515 sets of industrial data demonstrates that N_E can effectively assess the energy consumption-temperature matching degree for SRRF—exhibiting a negative correlation coefficient of −0.61 with temperature difference, while N_{E, M} enables accurate identification of the heat transfer characteristics of wide billets, with a negative correlation coefficient of −0.45 with W/H, confirming that wider billets exhibit lower shape-corrected energy redundancy. Analysis of the high-gradient region reveals that although wide billets in SRRF experience higher energy consumption due to extended heat conduction paths, their thermal efficiency outperforms that of narrow billets; optimization in this regard can be achieved through regulating rolling rhythm and furnace temperature. This system serves as a quantitative tool for SRRF to transition from empirical regulation to data-driven optimization. Theoretically, it breaks through the single-factor limitation of traditional methods; practically, it provides support for energy efficiency benchmarking and dynamic regulation of SRRF.

轧钢加热炉作为钢铁生产中关键的高耗能设备，其能效优化长期以来受到“能耗-温度匹配、轧制节奏-质量协调、钢坯形状-能效差异化”三大核心矛盾的制约。本研究建立了“通用细分”两层判据体系。通用准则（NE）通过实际能耗与理论热需求的比值来量化全球能耗冗余。同时，形状校正判据（NE， M）包含了宽度与厚度比（W/H）的校正项，以区分形状引起的固有损失和操作可控损失。1515组工业数据的验证表明，NE可以有效评估srrf的能量消耗-温度匹配度，与温差的负相关系数为- 0.61，而NE， M可以准确识别宽坯的传热特性，与W/H的负相关系数为- 0.45，证实了宽坯具有较低的形状校正能量冗余。对高梯度区域的分析表明，尽管宽坯在SRRF中由于热传导路径的延长而消耗了更高的能量，但其热效率优于窄坯；这方面的优化可以通过调节轧制节奏和炉温来实现。该系统是SRRF从经验调控向数据驱动优化过渡的定量工具。在理论上突破了传统方法单一因素的局限；实际上，它为SRRF的能效基准和动态调节提供了支持。

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引用次数: 0

ADAPTIVE AI scheduling of building HVAC to charge phase change thermal batteries with elevator regenerative braking heat 建筑暖通空调利用电梯制动蓄热给相变热电池充电的自适应AI调度

Measurement: Energy

Pub Date : 2025-11-21 DOI: 10.1016/j.meaene.2025.100079

Rajagopal M , Shashank R , Shreeshanth R

High-rise buildings consume significant energy due to intensive HVAC and elevator operations. This study proposes an adaptive energy management framework that captures regenerative braking heat from elevators to charge Phase-Change Thermal Batteries (PCTBs), which are subsequently used to assist HVAC operations. A hybrid co-simulation platform integrating TRNSYS, MATLAB/Simulink, and Python (TensorFlow) was developed to couple building thermal dynamics, elevator regenerative heat recovery, and AI-based HVAC scheduling. The proposed reinforcement learning (RL)–driven scheduler dynamically coordinates HVAC power modulation, PCTB charging/discharging cycles, and occupancy-based thermal demand in response to real-time weather and elevator activity. Simulation results demonstrate that the adaptive AI scheduler reduces HVAC energy consumption by up to 18 % and peak load by 12 %, while maintaining indoor comfort within ASHRAE-55 standards. Regenerative heat utilization efficiency exceeded 75 %, confirming effective capture and reuse of elevator braking energy. Extended seven-day simulations further validated system robustness and consistent performance under varying occupancy and climatic conditions. Economic assessment indicates a payback period of 5–7 years, emphasizing the financial viability of the proposed integration. By uniting regenerative energy recovery, latent thermal storage, and adaptive AI control, this research establishes a scalable framework for intelligent HVAC operation in smart buildings. The findings highlight substantial potential for achieving energy circularity, reduced carbon emissions, and enhanced sustainability in high-rise urban environments.

高层建筑由于密集的暖通空调和电梯运行而消耗大量能源。本研究提出了一种自适应能源管理框架，该框架可捕获电梯的再生制动热量，为相变热电池（pctb）充电，该电池随后用于辅助HVAC操作。开发了TRNSYS、MATLAB/Simulink和Python （TensorFlow）的混合联合仿真平台，以耦合建筑热动力学、电梯蓄热回收和基于人工智能的暖通空调调度。所提出的强化学习（RL）驱动的调度程序动态协调HVAC功率调制、PCTB充放电周期和基于占用的热需求，以响应实时天气和电梯活动。仿真结果表明，自适应人工智能调度器可将HVAC能耗降低18%，峰值负荷降低12%，同时将室内舒适度保持在ASHRAE-55标准内。蓄热利用率超过75%，确认了电梯制动能量的有效捕获和再利用。延长的7天模拟进一步验证了系统在不同占用率和气候条件下的稳健性和一致性性能。经济评估表明回收期为5-7年，强调拟议的一体化在财务上的可行性。本研究通过将可再生能源回收、潜热储存和自适应人工智能控制结合起来，建立了智能建筑智能暖通空调运行的可扩展框架。研究结果强调了在高层城市环境中实现能源循环、减少碳排放和增强可持续性的巨大潜力。

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引用次数: 0

Optimal VAr management of a large power network using most efficient method of weak node detection 基于最有效的弱节点检测方法的大型电网无功管理

Measurement: Energy

Pub Date : 2025-11-12 DOI: 10.1016/j.meaene.2025.100077

Biplab Bhattacharyya, Suraj Kumar Rajbhar

A robust method for weak node detection for optimal VAr allocation has been proposed in this research. Modal or eigenvalue analysis, loss-sensitivity analysis, power flow analysis, L-index, and fast voltage stability index methods were employed to identify weak nodes in medium and large power networks using IEEE 57 and IEEE 118 bus systems. After identifying the locations for shunt VAr allocation, several standard optimization techniques i.e. Genetic Algorithm, Differential Evolution, Particle Swarm Optimization, Teaching-Learning-Based Optimization, Big Bang-Big Crunch, Krill Herd Algorithm, and Sine-Cosine Algorithm were then applied for optimal reactive power planning. These methods were aimed to coordinate VAr injections by shunt capacitors at weak nodes with existing VAr sources such as generators and On-Load Tap Changers. A comprehensive study of various standard detection techniques and their usefulness in power system planning is presented by the authors. Finally, authors deduced LSI (Line Stability Index) method of weak node detection was the most accurate method for weak node detection. Carrying out the proposed methodology, the total active power loss with GA & DE was found as 0.2348 p.u. & 0.2351 p.u. respectively for IEEE 57 bus test network and total operating cost was found as $1.2344 × 10⁷ for GA & $1.2357 × 10⁷ for DE. Similarly, for the IEEE 118-bus test network, the active power loss reported under GA and DE was 1.3295 p.u. each, with corresponding operating costs of $6.9885 × 10⁷ and $6.9880 × 10⁷, respectively. This research offers a comprehensive framework for reducing operating cost and active power loss in reactive power planning.

本文提出了一种鲁棒的弱节点检测方法，用于VAr最优分配。采用模态或特征值分析、损耗敏感性分析、潮流分析、l指数和快速电压稳定指数等方法，对采用ieee57和ieee118母线系统的大中型电网中的薄弱节点进行了识别。在确定并联无功功分配位置后，应用遗传算法、差分进化算法、粒子群算法、基于教学-学习的优化算法、大爆炸-大压缩算法、磷虾群算法和正弦-余弦算法等标准优化技术进行无功规划优化。这些方法旨在通过在弱节点的并联电容器与现有的无功源（如发电机和有载分接开关）协调无功注入。作者对各种标准检测技术及其在电力系统规划中的应用进行了全面研究。最后，推导出基于线路稳定指数的弱节点检测方法是最准确的弱节点检测方法。采用所提出的方法，IEEE 57总线测试网络在GA和DE下的总有功功率损耗分别为0.2348 p.u.和0.2351 p.u.，总运行成本为1.2344 × 107美元；对于IEEE 118总线测试网络，在GA和DE下报告的有功功率损耗分别为1.3295 p.u.，相应的运行成本分别为6.9885 × 107美元和6.9880 × 107美元。该研究为降低无功规划中的运行成本和有功损耗提供了一个全面的框架。

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引用次数: 0

New insights into iron fuel combustion: integrated in-situ and ex-situ diagnostics of ignition delay, melting–oxidation, disruptive phenomena and nanoparticle sizing 铁燃料燃烧的新见解：点火延迟，熔化氧化，破坏现象和纳米颗粒尺寸的集成原位和非原位诊断

Measurement: Energy

Pub Date : 2025-11-11 DOI: 10.1016/j.meaene.2025.100073

Zakaria Mansouri

Iron powders are attracting growing interest as recyclable energy carriers, offering high-temperature heat release during combustion and the potential for a carbon-free, closed energy cycle. However, key aspects remain insufficiently characterised, including single-particle combustion times over broad size ranges and the formation, size and concentration of nanoparticles during combustion. This study provides the first experimental investigation of irregular iron particles up to 250 μm in size. Combustion experiments were conducted using a controlled gas-supply, a tri-concentric tube burner with a motorised powder injector, and a quartz drop tube leading to a stainless-steel chamber for by-product collection and gas sampling. In-situ diagnostics employed a high-speed camera and a photomultiplier tube (PMT) module, while nanoparticle sizing used an aerodynamic particle sizer (APS). Ex-situ characterisation was performed by scanning electron microscopy (SEM). PMT data combined with particle-size analysis yielded new correlations for ignition delay and liquid-phase oxidation times. Ignition delay follows a second-order polynomial relationship, in contrast to the power-law behaviour reported for spherical particles, while liquid-phase oxidation shows simultaneous melting and oxidation and may be more accurately termed the melting-oxidation phase. Particle growth rates during this phase indicated oxidation rates of approximately 10–20 μm/ms. At later stages, oxide-shell rupture led to the ejection of molten nanoparticles, producing a bright secondary oxidation phase beyond the particle surface. SEM micrographs revealed a variety of disruptive events, including inter-particle collisions, impacts with the surrounding quartz tube, partial oxidation, micro-explosions and the development of surface cavities. Real-time APS measurements of exhaust emissions further demonstrated a unimodal nanoparticle distribution with a peak at 583 nm and evidence suggesting the presence of sub-500 nm particles.

铁粉作为一种可回收的能量载体，在燃烧过程中提供高温热量释放，并有可能实现无碳、封闭的能量循环，正引起人们越来越多的兴趣。然而，关键方面的特征仍然不够充分，包括单颗粒在大尺寸范围内的燃烧时间以及燃烧过程中纳米颗粒的形成、大小和浓度。该研究首次对粒径达250 μm的不规则铁颗粒进行了实验研究。燃烧实验采用受控供气、带电动粉末喷射器的三同心管燃烧器，以及通向用于收集副产物和气体取样的不锈钢室的石英滴管进行。现场诊断采用了高速摄像机和光电倍增管（PMT）模块，而纳米颗粒分级则采用了气动粒度仪（APS）。通过扫描电镜（SEM）进行了非原位表征。PMT数据结合颗粒大小分析得出了点火延迟和液相氧化时间的新相关性。与球形颗粒的幂律行为相反，点火延迟遵循二阶多项式关系，而液相氧化显示同时熔化和氧化，可能更准确地称为熔化-氧化阶段。该阶段的颗粒生长速率表明氧化速率约为10-20 μm/ms。在后期阶段，氧化壳破裂导致熔融纳米颗粒喷射，在颗粒表面之外产生明亮的二次氧化相。SEM显微图显示了多种破坏事件，包括粒子间碰撞、与周围石英管的撞击、部分氧化、微爆炸和表面空腔的发展。废气排放的实时APS测量进一步证明了单峰纳米颗粒分布，峰值位于583纳米处，证据表明存在低于500纳米的颗粒。

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引用次数: 0

Passive cooling of Photovoltaic panels using radiative paints and metal foam fins: A critical review of mechanisms, materials, and performance metrics 使用辐射涂料和金属泡沫翅片的光伏板被动冷却：对机制、材料和性能指标的重要回顾

Measurement: Energy

Pub Date : 2025-11-11 DOI: 10.1016/j.meaene.2025.100076

Kehinde Temitope Alao , Kamaruzzaman Sopian , Syed Ihtsham Ul Haq Gilani , Jing Ee Yit , Shuib Husin , Taiwo Onaopemipo Alao , Zeshan Aslam , Hussein A. Kazem

The performance and lifespan of solar Photovoltaic (PV) panels can be drastically improved by minimizing thermal buildup, which can constrain performance. This review critically compares two trending passive cooling technologies, such as radiative paints and metal foam fins, across their mechanisms, materials, and performance metrics. Radiative paints that enable solar radiation reflection and thermal emission, and metal foam fins that increase heat dissipation by providing increased surface area, are investigated separately and in combination. We discuss the contributions of these techniques to reduced operational temperatures, improved energy yield, and enhanced PV panel longevity. The review integrates discussion of the materials used in these technologies, the difficulties in their implementation, and the need for standard test procedures. We also cover multidimensional performance tests, including thermal conductivity, cooling performance, and environmental footprint. The review also provides current research gaps and recommends future research and development directions in hybrid cooling systems, the incorporation of new materials, and large-scale experimental verification. The synthesis offers a comprehensive review of the prospects of passive cooling technologies for optimizing PV systems, with implications for both academic research and real-world applications in the solar industry.

太阳能光伏（PV）板的性能和寿命可以通过最大限度地减少限制性能的热积聚来大大提高。这篇综述比较了两种趋势的被动冷却技术，如辐射涂料和金属泡沫翅片，它们的机制、材料和性能指标。能够进行太阳辐射反射和热发射的辐射涂料，以及通过提供更大的表面积来增加散热的金属泡沫翅片，分别和组合进行了研究。我们讨论了这些技术在降低操作温度、提高能量产量和延长光伏面板寿命方面的贡献。这篇综述整合了对这些技术中使用的材料的讨论，它们实现中的困难，以及对标准测试程序的需求。我们还介绍了多维性能测试，包括导热性、冷却性能和环境足迹。综述还提供了当前的研究差距，并建议了混合冷却系统，新材料的结合和大规模实验验证的未来研究和发展方向。综合提供了优化PV系统的被动冷却技术的前景的全面回顾，对学术研究和太阳能行业的实际应用都有影响。

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引用次数: 0