Energy Conversion and Management最新文献_第6页

Assessing the impact of PEM electrolyser degradation for green hydrogen production: Power variability and ageing effects 评估PEM电解槽降解对绿色制氢的影响：功率变异性和老化效应

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-02-05 DOI: 10.1016/j.enconman.2026.121142

Ane Elizetxea-Navarro , Jon Aizpuru , Yerai Peña-Sanchez , Manu Centeno-Telleria , Ander Goikoetxea , Markel Penalba

Green hydrogen is a promising alternative to fossil fuels, supported by the growing interest in electrolysers and renewable-based hydrogen production. However, limited understanding remains regarding the degradation processes affecting electrolyser performance. This paper presents a comprehensive model that integrates three primary degradation mechanisms: (1) ageing or evolutionary operational degradation, understood as time-dependent wear accumulated during operating hours; (2) dynamic operational degradation due to renewable-induced load fluctuations; and (3) shutdown-related degradation caused by frequent start-ups and shut-downs driven by renewable intermittency. The model progressively evolves from a baseline case assuming a constant operational degradation rate to a refined formulation that accounts for variable operational degradation rates and intermittent shutdowns. Results indicate that shutdown events are the dominant factor driving electrolyser degradation. When shutdown-related degradation is considered, the degradation effect increases by at least threefold compared to constant operation. Conversely, variations in operational degradation rates have a minor influence on overall system performance. Over a 25-year wind-electrolysis plant lifetime, the number of required electrolysers changes by approximately 50% when shutdown effects are neglected and only 15% when they are included. The interaction of degradation mechanisms leads to non-linear effects and unpredictable trends, underscoring the importance of integrating all relevant degradation factors into system modelling and lifecycle assessment. The findings highlight the need for more precise experimental data to refine degradation rate estimations. Nevertheless, the proposed model provides the flexibility to incorporate updated parameters as new data become available, offering a robust framework for performance prediction and strategic planning in green hydrogen systems.

由于人们对电解槽和可再生制氢的兴趣日益浓厚，绿色氢是一种有前景的化石燃料替代品。然而，对影响电解槽性能的降解过程的了解仍然有限。本文提出了一个综合模型，该模型集成了三种主要的退化机制：(1)老化或演化的运行退化，被理解为在运行时间内积累的随时间变化的磨损；(2)可再生能源引起的负荷波动导致的动态运行退化；(3)可再生能源间歇性驱动的频繁启动和停机导致的停机相关退化。该模型逐渐从假设恒定运行退化率的基线情况演变为考虑可变运行退化率和间歇性停机的精炼公式。结果表明，停机事件是导致电解槽退化的主要因素。当考虑停机相关的退化时，与恒定运行相比，退化效应至少增加了三倍。相反，操作退化率的变化对整个系统性能的影响很小。在25年的风电解厂寿命中，当不考虑停机影响时，所需电解槽的数量变化约为50%，当考虑停机影响时，所需电解槽的数量变化仅为15%。退化机制的相互作用导致非线性效应和不可预测的趋势，强调了将所有相关退化因素纳入系统建模和生命周期评估的重要性。这一发现强调了需要更精确的实验数据来改进降解率估计。然而，所提出的模型提供了灵活性，可以在新数据可用时纳入更新的参数，为绿色氢系统的性能预测和战略规划提供了一个强大的框架。

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引用次数: 0

Energy, exergy, exergoeconomic and sustainability analysis of a propane-fueled SI engine operating via flame jet ignition using oxy-hydrogen gas from an on-board alkaline electrolyzer supported by TEG 能源、火用、燃烧、经济性和可持续性分析丙烷燃料SI发动机通过火焰喷射点火，使用由TEG支持的机载碱性电解槽产生的氧-氢气体

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-02-05 DOI: 10.1016/j.enconman.2026.121155

Hüsameddin Akçay , Halil Erdi Gülcan , Habib Gürbüz

This paper focuses on the energy, exergy, exergoeconomic, and sustainability performance of oxygen-hydrogen (HHO) gas utilization for flame jet ignition in a propane-fueled SI engine. The required HHO gas is produced instantaneously using an alkaline electrolyzer. A significant portion of its energy was provided by electrical energy generated from exhaust waste heat using a thermoelectric generator (TEG). The HHO assisted flame jet ignition (HHO_AJI) system ignites the propane-air mixture in the main combustion chamber using HHO gas delivered in different proportions to the pre-chamber. The HHO flow rates used in flame jet ignition were 0.4 L/min (HHO_AJI-0.4), 0.7 L/min (HHO_AJI-0.7), and 1.0 L/min (HHO_AJI-1.0). The experimental studies were conducted at a constant engine speed of 2300 rpm, 50% throttle opening, and six different lambda values (λ = 0.9, 1.0, 1.1, 1.2, 1.3, and 1.4). The results indicate that the HHO_AJI system enhances exergetic performance under lean mixture conditions. At λ = 1.4 and an HHO flow rate of 1.0 L.min-1 thermal efficiency, exergy efficiency, and sustainability index increased by 66.7%, 67.2%, and 14.2%, respectively, compared to conventional ignition, while lost energy and exergy destruction decreased by 18.3% and 14.3%. Moreover, the exergoeconomic analysis showed that the specific exergy cost of shaft power decreased by 6.5%, confirming that operating the SI engine with a lean mixture under HHO_AJI mode is not only thermodynamically but also economically advantageous.

本文主要研究了在丙烷燃料SI发动机中利用氢氧（HHO）气体进行火焰喷射点火的能源、火用、火用经济性和可持续性性能。所需的HHO气体使用碱性电解槽立即产生。其能量的很大一部分是由使用热电发电机（TEG）从废气废热产生的电能提供的。HHO辅助火焰喷射点火（HHO_AJI）系统将不同比例的HHO气体送入预燃室，点燃主燃烧室的丙烷-空气混合物。火焰喷射点火时的HHO流量分别为0.4 L/min （HHO_AJI-0.4）、0.7 L/min （HHO_AJI-0.7）和1.0 L/min （HHO_AJI-1.0）。实验研究是在发动机转速为2300转/分、50%油门开度和6个不同lambda值（λ = 0.9、1.0、1.1、1.2、1.3和1.4）的恒定条件下进行的。结果表明，HHO_AJI体系在稀薄混合料条件下提高了火用性能。λ = 1.4和HHO流量为1.0 l min-1时，与常规点火相比，火用效率和可持续性指数分别提高了66.7%、67.2%和14.2%，能量损失和火用破坏分别降低了18.3%和14.3%。此外，燃烧经济性分析表明，轴功率的比火用成本降低了6.5%，证实了在HHO_AJI模式下使用稀薄混合气运行SI发动机不仅热力学上有利，而且经济上有利。

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引用次数: 0

Optimal management of backup power supply resources for critical infrastructure sites using mobile electricity storage facilities 基于移动蓄电的关键基础设施备用电源资源优化管理

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-02-05 DOI: 10.1016/j.enconman.2026.121169

Krzysztof Zagrajek , Desire D. Rasolomampionona , Mariusz Kłos , Enrico Elio De Tuglie , Giulia Amato , Luigi Pio Savastio

In modern power systems, low-emission backup power resources (BPR) are being explored to enhance the reliability of power supply and strengthen the energy resilience of critical infrastructure. One such resource is mobile energy storage facilities (MESF). They take the form of custom electric vehicles (CEV) with MESF in their cargo space. The aim of this article is to investigate the optimal mix of energy potential available with resources such as Vehicle-to-Grid (V2G) and CEV vehicles supported by a local diesel generator. The article proposes a research methodology for assessing the economic viability of deploying energy services using MESF to improve the energy security of priority loads, especially critical infrastructure sites by minimizing the cost of electricity supply from the BPR mix. The reference point is the value of energy not delivered, estimated using the value of lost load (VOLL) indicator. The study included 18 test simulations of BPR resource dispatch over the course of a year, considering the hourly power demand profile of the end-user and the probability of grid constraints. The results indicate that economic viability is achieved when service activation exceeds 125 h, and the profits from using such resources can reach almost EUR 2 million. For 6 out 18 applied testing scenarios, the profits of using BPR’s optimal mix were recorded, ranging from 168,000 EUR to 1,824,693 EUR. The results demonstrate that it is possible to utilize CEV vehicles in enhancing the energy resilience of critical infrastructure, using it as one of resources alongside V2G technology and Diesel Generators.

在现代电力系统中，为了提高供电可靠性和增强关键基础设施的能源弹性，正在探索低排放备用电源。其中一种资源是移动储能设施（MESF）。它们采用定制电动汽车（CEV）的形式，在其货舱中装有MESF。本文的目的是研究由本地柴油发电机支持的车辆到电网（V2G）和CEV车辆等资源可获得的能源潜力的最佳组合。本文提出了一种研究方法，用于评估使用MESF部署能源服务的经济可行性，通过最小化BPR组合的电力供应成本来提高优先负载的能源安全性，特别是关键基础设施站点。参考点是未交付的能量值，使用失负荷（VOLL）指标的值估计。该研究包括在一年的时间里对BPR资源调度进行的18次测试模拟，考虑到最终用户的小时电力需求概况和电网约束的可能性。结果表明，当服务激活超过125小时时，实现了经济可行性，使用这些资源的利润可达到近200万欧元。对于18个应用测试场景中的6个，使用BPR的最佳组合的利润记录，从168,000欧元到1,824,693欧元不等。结果表明，利用CEV车辆增强关键基础设施的能源弹性是可能的，将其与V2G技术和柴油发电机一起用作资源之一。

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引用次数: 0

Increased energy conversion efficiency in footstep energy harvesting pavements via a novel combination strategy 通过一种新颖的组合策略提高了步行能量收集路面的能量转换效率

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-02-05 DOI: 10.1016/j.enconman.2026.121178

Rui Zhong , Chung Ket Thein , Dunant Halim , John Xu , Chenjun Shi

For an array composed of multiple footstep energy harvesting pavements (FEHPs), a critical challenge that limits large-scale application is the energy loss with reliability degradation caused by the combination of multiple harvesters under normal footstep displacement. To eliminate this problem, a novel combination strategy was proposed in this work to autonomously route current around inactive harvesters. Concurrently, a mechanical switching system free from external power supply was manufactured to serve as the actuator of proposed strategy. Furthermore, an accurate mathematical model was established for the array implementing the proposed strategy. The strategy demonstrates a strong universality, being applicable to any FEHP that exchanges power through displacement, as the displacement is set to a pedestrian-friendly 5 mm in this work. The combination strategy not only enables the FEHP array to reach higher energy conversion efficiency but also ensures the smooth delivery of electrical energy generated by multiple FEHPs working simultaneously. In experimental verification, a single action on one switching module within the array achieved a 33.3% output voltage increase compared to the conventional series-connection method under given conditions. For an array consisting of three FEHPs in demonstration test, the new strategy facilitates threshold voltage breakthrough under given conditions, yielding a peak DC output of 20 V for a resistor box and a stable power supply duration of 22 s for a thermo-hygrometer. These results validate the effectiveness of the proposed device and the superiority of the combination strategy, highlighting their application value and market potential in energy harvesting.

对于由多个足部能量收集路面（fehp）组成的阵列来说，限制大规模应用的一个关键挑战是，在正常足部位移下，多个足部能量收集路面组合导致的能量损失和可靠性下降。为了消除这一问题，本文提出了一种新的组合策略，在非活动收集器周围自主布线电流。同时，制造了一个无外部电源的机械开关系统作为该策略的执行器。在此基础上，建立了实现该策略的精确数学模型。该策略具有很强的通用性，适用于任何通过位移交换功率的FEHP，因为在这项工作中，位移被设置为对行人友好的5毫米。该组合策略不仅可以使FEHP阵列达到更高的能量转换效率，还可以保证多个FEHP同时工作时产生的电能的平稳输送。在实验验证中，在给定条件下，与传统串联连接方法相比，阵列内一个开关模块的单次动作可使输出电压提高33.3%。在演示测试中，对于由三个fehp组成的阵列，新策略有助于在给定条件下突破阈值电压，电阻箱的峰值直流输出为20 V，热湿度计的稳定供电持续时间为22 s。这些结果验证了该装置的有效性和组合策略的优越性，突出了其在能量收集方面的应用价值和市场潜力。

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引用次数: 0

Techno-economic analysis of closed-loop geothermal system with multi-wing fracture 多翼裂缝闭环地热系统技术经济分析

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-02-05 DOI: 10.1016/j.enconman.2026.121174

Sai Liu, Ruichang Guo, Chao Li, Hongsheng Wang

This research seeks to determine whether thermally conductive fractures can substantially enhance the heat extraction of closed-loop geothermal systems. A fracture-incorporated closed-loop geothermal system, featuring a multi-wing thermally conductive fracture, is presented. A thermo-hydraulic coupled three-dimensional model is established for the system, through which an extensive numerical investigation is conducted to assess its heat extraction under circumstances of various fracture heat conductivity, multi-wing fracture configurations, and operational settings. Results indicate that a system with a dual-wing fracture attains moderately greater heat extraction than a fracture-free closed-loop design, when the fracture has large height and thickness, with performance increasing as fracture heat conductivity rises. For an identical fracture cross-sectional area, increasing fracture height provides more substantial heat extraction enhancement than expanding fracture thickness. Elevating the specific heat capacity of circulating fluid reduces the produced-fluid temperature considerably, although the corresponding improvement in net power remains modest. As the fluid circulation rate increases, cumulative thermal output initially climbs but eventually decreases once a threshold flow rate is exceeded. Implementing a multi-wing fracture yields up to a 60.93% increase in cumulative heat output over 180 days, and this improvement reaches 187.25% when a thermal plug is additionally utilized. The thermal output increment associated with the thermal plug plateaus near 78.51% when the number of fracture wings is greater than four. Among all influencing parameters, the thermal plug, followed by the fracture wing number, exerts the greatest effect on the closed-loop system’s thermal performance. The F-CGS with a dual-wing fracture and plug exhibits superior economy.

本研究旨在确定导热裂缝是否能显著增强闭环地热系统的热提取。提出了一种以多翼式导热裂缝为特征的裂缝合并闭环地热系统。建立了该系统的热-液耦合三维模型，对不同裂缝导热系数、多翼裂缝构型和操作条件下的抽热量进行了广泛的数值研究。结果表明，当裂缝具有较大的高度和厚度时，具有双翼裂缝的系统比无裂缝的闭环设计获得了中等程度的热量提取，并且性能随着裂缝导热系数的增加而提高。在相同的裂缝截面积下，增加裂缝高度比增加裂缝厚度提供更显著的排热效果。提高循环流体的比热容可以显著降低产液温度，但相应的净功率改善仍然不大。随着流体循环速率的增加，累积热输出开始上升，但一旦超过阈值流量，最终会下降。在180天内，实施多翼压裂可使累计热输出增加60.93%，如果额外使用热塞，则可提高187.25%。当裂缝翼数大于4个时，与热塞平台相关的热输出增量接近78.51%。在所有影响参数中，热塞对闭环系统热性能的影响最大，其次是断裂翼数。具有双翼裂缝和桥塞的F-CGS具有优越的经济性。

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引用次数: 0

Advanced computational fluid dynamic analysis of microclimate effects on solar photovoltaics for the utility-scale solar industry 微气候对公用事业规模太阳能产业太阳能光伏发电影响的先进计算流体动力学分析

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-02-05 DOI: 10.1016/j.enconman.2026.121153

Sahan Trushad Wickramasooriya Kuruneru, Kenrick Anderson, Andrew Beath

An advanced numerical model is developed to unravel novel fluid flow physics and heat transfer mechanisms of three distinct bifacial solar photovoltaic panels (BPVs), namely 25° fixed-tilt, 90° vertical-, and waves-oriented BPVs. To this end, a conjugate heat transfer (CHT) numerical model is developed in the open-source computational fluid dynamics (CFD) software OpenFOAM to unravel novel buoyant convective-radiative fluid flow physics and microclimate of the three distinct BPVs in the region of Newcastle NSW Australia. The CFD results show that the air flow pathways, panel temperature distribution and air temperature around the panels vary considerably with differing geometric panel morphology and climate conditions. Distinct flow patterns are observed in different panels of the solar farm. It is also found that the number of air recirculation zones between successive panels in a solar farm vary due to various factors such as head-on wind velocity magnitudes, wind directions, and panel tilt and panel spacing thereby altering the spatial temperature distribution of all PV panels. This also has profound implications on the local air velocities and heat transfer coefficients of BPVs. The effects of wind directions on BPVs have distinct heat transfer characteristics. Scientists and engineers in the photovoltaic industry can harness this approach to broaden the applicability and generalizability of PV heat transfer models by developing and implementing advanced CFD models to provide various correlations between heat transfer coefficients and head-on wind velocities and wind directions. Furthermore, the numerical model and the results can be harnessed to facilitate and guide the system optimization of BPVs for various industries such as agriculture and mining.

建立了一种先进的数值模型，揭示了三种不同的双面太阳能光伏板（25°固定倾斜，90°垂直和波浪方向的双面太阳能光伏板）的新型流体流动物理和传热机制。为此，在开源计算流体动力学（CFD）软件OpenFOAM中建立了一个共轭传热（CHT）数值模型，以揭示澳大利亚新南威尔士州纽卡斯尔地区三种不同bpv的新型浮力对流辐射流体流动物理和小气候。计算流体力学结果表明，不同几何形状和气候条件下，面板的气流路径、面板温度分布和面板周围的空气温度变化较大。在太阳能发电厂的不同面板上观察到不同的流动模式。研究还发现，太阳能发电厂连续面板之间的空气再循环区数量会因各种因素而变化，例如迎面风速大小、风向、面板倾斜和面板间距，从而改变所有光伏面板的空间温度分布。这对bpv的局部空气速度和换热系数也有深远的影响。风向对bpv的影响具有明显的换热特性。光伏行业的科学家和工程师可以利用这种方法，通过开发和实施先进的CFD模型来提供传热系数与迎面风速和风向之间的各种相关性，从而扩大光伏传热模型的适用性和通用性。此外，数值模型和结果可用于促进和指导农业和采矿业等不同行业的业务流程pv系统优化。

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引用次数: 0

Air liquefaction process in liquid air energy storage integrated with liquefied natural gas cold energy: Simulation and experiment 结合液化天然气冷能的液态空气储能中的空气液化过程：模拟与实验

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-02-04 DOI: 10.1016/j.enconman.2026.121177

Chenchen Wang, Jinya Zhang, Ning Ma, Na Sun

The growing demand for efficient air liquefaction, driven by renewable energy integration and industrial needs, faces practical bottlenecks of the pressure limits of cryogenic heat exchangers (≤10 MPa) and the actual temperature range of liquefied natural gas cold energy (−145℃ to −135℃). In this study, multiple air liquefaction cycles integrated with internal (liquid air) and external (liquefied natural gas) cold energy are systematically modeled, optimized using a genetic algorithm, and experimentally validated under pressures ranging from 1 to 10 MPa. The experimental results indicate that the optimized Heylandt cycle is identified as the most efficient configuration for stand-alone liquid air energy storage, achieving a specific energy consumption of 0.3192 kWh/kg with a cold energy recovery rate of 95%. For liquefied natural gas integrated with liquid air energy storage system, the Kapitza cycle exhibits superior performance, attaining a specific energy consumption of 0.1980 kWh/kg under a liquefied natural gas flow ratio of 0.45. Experimental validation confirms that the Kapitza cycle integrated with cold energy significantly enhances the round-trip efficiency of a 50-kW system to 54.2%, with projections indicating potential efficiencies exceeding 70% for scaled 10  MW systems. This work provides the first experimentally validated optimization of air liquefaction cycles under real-world engineering constraints, bridging a critical gap between simulation and practice. The resulting framework offers a novel and scalable pathway to high-efficiency cryogenic energy storage.

在可再生能源整合和工业需求的推动下，高效空气液化需求不断增长，但低温换热器的压力极限（≤10 MPa）和液化天然气冷能的实际温度范围（- 145℃至- 135℃）面临着现实瓶颈。在本研究中，对集成了内部（液态空气）和外部（液化天然气）冷能的多个空气液化循环进行了系统建模，使用遗传算法进行了优化，并在1至10 MPa的压力范围内进行了实验验证。实验结果表明，优化后的Heylandt循环是最有效的单机液空储能配置，比能耗为0.3192 kWh/kg，冷能回收率为95%。对于与液空储能系统集成的液化天然气，Kapitza循环表现出优异的性能，在液化天然气流量比为0.45的情况下，其比能耗为0.1980 kWh/kg。实验验证证实，与冷能集成的Kapitza循环显着提高了50 kw系统的往返效率，达到54.2%，预测表明10  MW系统的潜在效率超过70%。这项工作提供了第一个在现实世界工程约束下经过实验验证的空气液化循环优化，弥合了模拟与实践之间的关键差距。由此产生的框架为高效低温储能提供了一种新颖且可扩展的途径。

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引用次数: 0

Energy, exergy and mass balances of a biomass pyrolysis pilot plant 生物质热解试验装置的能量、火用和质量平衡

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-02-04 DOI: 10.1016/j.enconman.2026.121154

César Gracia-Monforte , Alejandro Lete , Frédéric Marias , Javier Ábrego , Jesús Arauzo

This work presents the methodology and results of the energy, exergy, and mass balances of a fixed-bed downdraft biomass pyrolysis pilot plant. The analysis covers different operating modes: pyrolysis without energy recovery, with energy recovery from products, and with combustion of non-condensable gases including exhaust-gas heat recovery. The proposed framework enables consistent comparison of energy and exergy performance under varying process configurations. Experimental results show that the external heat demand of the pyrolysis process strongly depends on the energy recovery strategy. When products are cooled to the reference state, the required heat input is approximately 1.3 MJ/kg, increasing to about 3 MJ/kg when products leave at the pyrolysis temperature. The combustion of process gases significantly reduces this demand, while integrating exhaust-gas heat recovery leads to quasi-autothermal operation. Exergy analysis reveals that gas combustion and heat recovery lower exergy efficiency due to the conversion of high-quality pyrogases into exhaust gases. Nevertheless, the methodology developed allows quantifying these trade-offs and provides a comprehensive tool to evaluate process integration strategies in biomass pyrolysis systems aimed at improved thermal performance and sustainability.

这项工作提出的方法和结果的能量，火用，和质量平衡的固定床下吸式生物质热解试点工厂。分析涵盖了不回收能量的热解、产品回收能量的热解和不凝气体燃烧包括废气热回收的三种运行模式。提出的框架能够在不同工艺配置下对能源和能源性能进行一致的比较。实验结果表明，热解过程的外热需求很大程度上取决于能量回收策略。当产品冷却到参考状态时，所需的热量输入约为1.3 MJ/kg，当产品在热解温度下离开时，所需的热量输入约为3 MJ/kg。过程气体的燃烧显著降低了这一需求，同时整合废气热回收导致准自热操作。火用分析表明，燃气燃烧和热回收降低了火用效率，因为高质量的热解酶转化为废气。然而，所开发的方法允许量化这些权衡，并提供了一个全面的工具来评估生物质热解系统的过程集成策略，旨在改善热性能和可持续性。

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引用次数: 0

Multi-zone cooling strategy for dead-end proton exchange membrane fuel cells: Enhancing performance, water-thermal balance and durability 终端质子交换膜燃料电池的多区域冷却策略：提高性能、水热平衡和耐久性

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-02-04 DOI: 10.1016/j.enconman.2026.121151

Zhangda Liu , Zhan Gao , Houchang Pei , Qi Li , Zhengkai Tu

Proton exchange membrane fuel cells operating in dead-end mode suffer from spatially coupled water-thermal non-uniformities, which lead to inlet membrane dehydration and outlet flooding, jointly degrading performance and durability. Conventional uniform cooling strategies cannot effectively decouple these competing phenomena, which motivates the development of spatially differentiated thermal management approaches. A multi-zone cooling strategy has been developed to enable independent precision control of three temperature zones (30°C/60°C/80°C) within a single cell. This innovation achieves synergistic water-thermal regulation by actively leveraging thermal gradients: Outlet flooding is suppressed through a localized high-temperature zone (80°C) that enhances liquid water evaporation; Inlet membrane dehydration is prevented via a cooler upper zone (30°C) that promotes water retention; Compared with integral cooling at 60°C, the optimized multi-zone cooling improved current–density uniformity by 45.49%, reduced ohmic resistance by up to 26.12%, and increased cell voltage by 6.86% at 1100 mA·cm-2, while decreasing electrochemical surface area loss from 38.52% to 7.16% and suppressing the growth of hydrogen crossover by 59.57% over 120 h These results indicate that multi-zone cooling can effectively decouple water-thermal failure modes in dead-end operation and significantly enhance performance stability and durability, highlighting its potential for advanced thermal management in proton exchange membrane fuel cells.

在终端模式下运行的质子交换膜燃料电池存在空间耦合的水-热不均匀性，导致进口膜脱水和出口淹水，共同降低了性能和耐久性。传统的均匀冷却策略不能有效地解耦这些竞争现象，这促使了空间差异化热管理方法的发展。开发了多区域冷却策略，可以在单个电池内独立精确控制三个温度区域（30°C/60°C/80°C）。这一创新通过积极利用热梯度实现了水热协同调节：通过局部高温区（80°C）抑制出口注水，促进液态水蒸发；通过较冷的上部区域（30°C）防止进口膜脱水，促进水潴留；与60℃整体冷却相比，优化后的多区冷却使电流密度均匀性提高了45.49%，欧姆电阻降低了26.12%，1100 mA·cm-2时电池电压提高了6.86%；在120 h内，电化学表面积损失从38.52%降低到7.16%，氢交叉的增长降低了59.57%。这些结果表明，多区冷却可以有效地解耦合死角运行中的水热失效模式，显著提高性能的稳定性和耐久性，突出了其在质子交换膜燃料电池高级热管理方面的潜力。

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引用次数: 0

Identifying environmental hotspots in an industrial anaerobic digestion power plant for integration into the Canadian waste management system: A life cycle perspective 确定一个工业厌氧消化发电厂的环境热点，以整合到加拿大废物管理系统：一个生命周期的观点

IF 10.4 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-02-03 DOI: 10.1016/j.enconman.2026.121145

Salman Soltanian, Maryam Ebrahimzadeh Sarvestani, Omid Norouzi, Francesco Di Maria, Animesh Dutta

引用次数: 0