Energy Conversion and Management最新文献_第3页

Unlocking flexibility value in energy communities: an assessment across multiple energy markets in Portugal 释放能源社区的灵活性价值：对葡萄牙多个能源市场的评估

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-04-01 Epub Date: 2026-02-13 DOI: 10.1016/j.enconman.2026.121173

João Victor Costa, Diogo Couceiro, Diana Neves

Energy communities are emerging as key enablers of decentralised, locally autonomous and resilient energy systems, in which third-party aggregators play a crucial role in managing demand-side flexibility across markets. This study addresses the need for a quantitative, multi-market assessment of how residential flexibility from energy communities can be optimally scheduled considering a case study in Portugal. The central premise is that an independent aggregator can pool and manage residential flexibility in ways that generate additional value streams for both the community and the aggregator through differentiated market-participation strategies. A multi-objective optimisation framework is applied to a residential energy community equipped with photovoltaic generation, a battery energy storage system, and flexible loads. A profit-redistribution mechanism to co-optimise community cost savings and aggregator profit from trading flexibility is tested across the Day-Ahead, Intraday, automatic Frequency Restoration Reserve, and Local Flexibility Markets. Results show aggregator net profits between 1.0–19.5%, up to 1281 €/year, and community energy cost reductions between 2.0–28.8%, up to 405 € annually by participant, with revenue stacking providing additional gains. Peak-load reductions reach up to 17%, while the Self-Sufficiency Ratio varies from 29.7% to 31.4%. Reserve services and local flexibility markets deliver higher economic benefits than wholesale price arbitrage, but their practical use is constrained by market entry thresholds, respectively 1 MW and 0.01 MW. Adequate remuneration for the participants will also depend on explicit profit-redistribution schemes to ensure balanced outcomes.

能源社区正在成为分散、地方自治和弹性能源系统的关键推动者，其中第三方聚合商在管理整个市场的需求侧灵活性方面发挥着关键作用。本研究以葡萄牙为例，对能源社区的住宅灵活性如何进行最佳安排进行了定量、多市场评估。核心前提是，一个独立的集成商可以汇集和管理住宅灵活性，通过差异化的市场参与策略为社区和集成商创造额外的价值流。多目标优化框架应用于配备光伏发电、电池储能系统和灵活负载的住宅能源社区。在前一天、盘中、自动频率恢复储备和本地灵活性市场中，对利润再分配机制进行了测试，以共同优化社区成本节约和交易灵活性带来的聚合利润。结果显示，集成商的净利润在1.0-19.5%之间，最高可达1281欧元/年，社区能源成本降低在2.0-28.8%之间，参与者每年可达405欧元，收入叠加提供了额外的收益。峰值负荷降幅高达17%，自给率从29.7%到31.4%不等。储备服务和本地弹性市场比批发价格套利提供更高的经济效益，但它们的实际使用受到市场准入门槛的限制，分别为1兆瓦和0.01兆瓦。为参与者提供足够的报酬，还将取决于明确的利润再分配方案，以确保平衡的结果。

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引用次数: 0

Effect of pressure on emission and transition characteristics of ammonia/hydrogen flameless combustion at high thermal intensities for carbon-free gas turbine applications 压力对无碳燃气轮机高热强度氨/氢无焰燃烧排放和转变特性的影响

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-04-01 Epub Date: 2026-02-13 DOI: 10.1016/j.enconman.2026.121219

Mohammad Kalamuddin Ansari, Zahra Mundrawala, Amber Tomar, Sudarshan Kumar

This study presents an experimental and numerical investigation of turbulent non-premixed ammonia/hydrogen combustion under high-pressure (1–5 bar) and high-thermal-intensity conditions in a flameless combustion regime relevant to carbon-free gas turbine applications. Experiments conducted in a conical combustor with offset tangential air injection are complemented by a chemical reactor network (CRN) and CFD simulations. Results show a systematic reduction in NO_x emissions with increasing pressure, attributed to altered reaction pathways and extended residence times. Image-based flame diagnostics helped investigate thermal gradients and intensity distributions as possible indicators of the transition from conventional to flameless combustion mode. These diagnostics reveal pressure-dependent changes in flame structure, indicating a transition from uniform flameless combustion at low pressure to localized ignition and stronger thermal gradients at higher pressures. The influence of equivalence ratio on flame uniformity and luminosity is also identified. Overall, this work demonstrates the technical feasibility of high-pressure NH₃/H₂ flameless combustion and highlights its strong potential as an emission-control strategy for carbon-free gas turbine systems.

本研究对与无碳燃气轮机应用相关的高压（1-5 bar）和高热强条件下无焰燃烧状态下的湍流非预混氨/氢燃烧进行了实验和数值研究。在锥形燃烧室中进行了偏置切向空气喷射实验，并辅以化学反应器网络（CRN）和CFD模拟。结果表明，随着压力的增加，由于反应途径的改变和停留时间的延长，氮氧化物排放系统减少。基于图像的火焰诊断有助于研究热梯度和强度分布，作为从传统燃烧模式过渡到无焰燃烧模式的可能指标。这些诊断揭示了火焰结构的压力依赖性变化，表明从低压下均匀无焰燃烧到高压下局部点火和更强热梯度的转变。确定了等效比对火焰均匀性和亮度的影响。总的来说，这项工作证明了高压NH3/H2无焰燃烧的技术可行性，并突出了其作为无碳燃气轮机系统排放控制策略的强大潜力。

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引用次数: 0

Impact of distributed battery energy storage controlled by optimization-based home energy management systems implementing various objective functions on the voltage profiles in the low-voltage network with a high saturation of prosumer photovoltaic micro-installations 实现多种目标函数的基于优化的家庭能源管理系统控制分布式电池储能对产消级光伏微装置高饱和低压电网电压分布的影响

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-04-01 Epub Date: 2026-02-08 DOI: 10.1016/j.enconman.2026.121148

Roman Korab , Marcin Połomski , Marcin Smołka , Tomasz Naczyński

Prosumer photovoltaic (PV) micro-installations change the operating conditions of low-voltage (LV) networks. When these networks are highly saturated with PV sources, some disruptions in their operation may occur periodically. In particular, long-term overvoltages are a frequent phenomenon, the most noticeable effect of which is the shutdown of PV sources. The simulation results showed that long-term overvoltages could affect more than a third of the customers supplied from a real LV rural network and last up to 383 h per year. As a result, the yearly generation of the PV source can be reduced by up to 25.6%. The method of overvoltages mitigation analyzed in this article consists in changing the unfavorable power balance using distributed battery energy storage systems (BESSs). However, the effectiveness of this voltage control method depends on the adopted control strategy for the BESSs. In this article, distributed BESSs are assumed to be controlled by individual, optimization-based home energy management systems (HEMSs). Using a model of a real LV rural network, the impact of BESSs operating according to the schedules resulting from two objective functions of HEMSs (i.e., energy cost minimization and maximization of prosumer financial neutrality) are compared. Better results are achieved when BESSs are operated according to profiles that maximize the financial neutrality of prosumers. In this case, the maximum duration of long-term overvoltages is reduced from 383 to 231 h per year, compared with 251 h when the BESSs are controlled in a way that minimizes energy costs, while the yearly reduction in PV generation is 16.1% and 17.9%, respectively.

产消级光伏（PV）微型装置改变了低压（LV）电网的运行条件。当这些网络的光伏电源高度饱和时，它们的运行可能会周期性地发生一些中断。特别是，长期过电压是一种常见的现象，其最显著的影响是光伏电源的关闭。仿真结果表明，长期过电压可能会影响超过三分之一的客户，这些客户来自真实的低压农村网络，每年持续383小时。因此，光伏发电的年发电量可以减少高达25.6%。本文分析的过电压缓解方法是利用分布式电池储能系统（BESSs）改变不利的功率平衡。然而，这种电压控制方法的有效性取决于bess所采用的控制策略。在本文中，分布式bess被假设为由单个的、基于优化的家庭能源管理系统（hems）控制。利用实际低电压农村电网模型，比较了低电压农村电网根据低电压农村电网的两个目标函数（即能源成本最小化和产消财务中立最大化）所产生的时间表运行bess的影响。当bess根据最大限度地提高产消者财务中立性的概况进行操作时，可以取得更好的结果。在这种情况下，长期过电压的最长持续时间从383小时/年减少到231小时/年，而以最小化能源成本的方式控制bess的最长持续时间为251小时/年，而光伏发电的年减少量分别为16.1%和17.9%。

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引用次数: 0

Dual evaporating temperature steam generation heat pump system for waste heat recovery of air–liquid hybrid cooling data center 气液混合冷却数据中心余热回收的双蒸发温度蒸汽发生热泵系统

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-04-01 Epub Date: 2026-02-12 DOI: 10.1016/j.enconman.2026.121199

Ce Zhang , Minxia Li , Xun Chen , Chaobin Dang , Xiuming Li , Zongwei Han

As information technologies such as ChatGPT, cloud computing, and 5G continue to evolve, data centers are consuming an escalating amount of energy. Data centers require year-round, uninterrupted cooling. However, traditional cooling technology faces the following challenges. On the one hand, the cooling capacity of air cooling technology is poor, and the initial investment of liquid cooling technology is high. On the other hand, waste heat from data center cooling system is directly discharged into the environment, the energy utilization efficiency is low. To solve the above problems, a novel thermal management scheme for data centers is proposed in this study. Regarding the data center cooling, the novel scheme is constructed based on an air–liquid hybrid cooling architecture to balance energy efficiency performance with technical feasibility. Regarding the air–liquid hybrid cooling architecture waste heat recovery, steam is generated through the dual evaporating temperature heat pump system, which enables synergistic recovery of waste heat from both the air and liquid cooling modules. The theoretical analysis and experimental research are conducted to compare the novel scheme with traditional scheme. The results show that in three typical cities, the operating cost, carbon emission, and life cycle cost of the novel scheme can be reduced by more than 15%.

随着ChatGPT、云计算和5G等信息技术的不断发展，数据中心正在消耗越来越多的能源。数据中心需要全年不间断的冷却。然而，传统的冷却技术面临着以下挑战。一方面，风冷技术的冷却能力较差，而液冷技术的初期投资较高。另一方面，数据中心冷却系统产生的余热直接排放到环境中，能源利用效率低。为解决上述问题，本研究提出一种新的数据中心热管理方案。在数据中心冷却方面，基于气液混合冷却架构构建了新的方案，以平衡能效性能和技术可行性。对于气液混合冷却架构余热回收，蒸汽通过双蒸发温度热泵系统产生，使空气和液体冷却模块的余热协同回收。对新方案与传统方案进行了理论分析和实验研究。结果表明，在三个典型城市，新方案的运行成本、碳排放和生命周期成本可降低15%以上。

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引用次数: 0

A novel approach to improving refrigeration cycle performance: using a two-stage intermediary heat exchanger and ultrasonic humidifying system along with economic analyses 一种改进制冷循环性能的新方法：采用两级中间热交换器和超声加湿系统并进行经济分析

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-04-01 Epub Date: 2026-02-10 DOI: 10.1016/j.enconman.2026.121198

Amin Jodat , Mojtaba Najafian , Amin Emamian , Babak Erfan Manesh , Mohammad Sheykhi , Shunmin Zhu

Energy efficiency is a critical challenge in conventional refrigeration systems, which often suffer from significant energy losses due to waste heat dissipation and inefficient disposal of condensate water from the evaporator, contributing to higher operational costs and environmental impacts. Despite advances in refrigeration technologies, integrated approaches combining heat recovery and evaporative pre-cooling remain underexplored. To address this research gap, this study investigates the potential of integrating an intermediate heat exchanger with a nebulizer to enhance the performance of an air-cooled vapor compression refrigeration cycle. An experimental setup comprising a 200 cm × 35 cm × 35 cm air-conditioning tunnel and a 3.5 kW R404a refrigeration cycle equipped with PLC-based temperature and pressure monitoring was constructed under controlled laboratory conditions. Airflow and temperature were controlled using a variable-speed blower and PID-regulated heaters/evaporator, while water flow through a shell-and-tube heat exchanger (preheating domestic water for later use) was varied from 60 to 240 L/h. Results indicate that increasing water flow to 240 L/h reduces compressor power consumption by 17% and improves the system’s coefficient of performance by more than threefold. Similarly, lowering the condenser inlet air temperature by 7 °C using a nebulizer decreases compressor power demand by 3.8% and enhances the coefficient of performance by 1.53-fold. Economic analysis shows that heat recovery with a water flow rate of 210 L/h can achieve annual savings of approximately $300, whereas the nebulizer implementation entails a payback period exceeding five years. Furthermore, the nebulizer offers a strategic operational benefit by preventing system shutdown during periods of high ambient temperature (exceeding the refrigeration cycle’s design point) through condenser cooling, thereby avoiding operational interruptions and potential losses. These findings demonstrate the substantial technical and economic benefits of combining heat recovery and evaporative pre-cooling in conventional refrigeration systems, offering a promising strategy for energy-efficient and sustainable cooling.

能源效率是传统制冷系统面临的一个关键挑战，由于废热消散和蒸发器冷凝水处理效率低下，传统制冷系统经常遭受巨大的能量损失，从而导致更高的运行成本和环境影响。尽管制冷技术取得了进步，但结合热回收和蒸发预冷的综合方法仍未得到充分探索。为了解决这一研究缺口，本研究探讨了将中间热交换器与雾化器集成以提高风冷蒸汽压缩制冷循环性能的潜力。在可控的实验室条件下，搭建了一个由200 cm × 35 cm × 35 cm空调隧道和3.5 kW R404a制冷循环组成的实验装置，并配有plc温度和压力监测系统。气流和温度由变速鼓风机和pid调节加热器/蒸发器控制，而水流量通过管壳式换热器（预热生活用水以备后用）从60到240 L/h不等。结果表明，将水流量提高到240 L/h，压缩机功耗降低17%，系统性能系数提高3倍以上。同样，使用雾化器将冷凝器入口空气温度降低7°C，压缩机功率需求降低3.8%，性能系数提高1.53倍。经济分析表明，以210升/小时的水流量进行热回收，每年可节省约300美元，而雾化器的实施需要超过5年的投资回收期。此外，该雾化器通过冷凝器冷却，防止系统在高环境温度（超过制冷循环的设计点）期间关闭，从而避免了运行中断和潜在的损失，从而提供了战略运行效益。这些发现表明，将热回收和蒸发预冷结合在传统制冷系统中具有巨大的技术和经济效益，为节能和可持续冷却提供了一种有前途的策略。

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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 : 2026-04-01 Epub 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 : 2026-04-01 Epub 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 : 2026-04-01 Epub 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

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 : 2026-04-01 Epub 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

A momentum decomposition analysis of Tesla turbines: Phase-dependent slip effects and design implications for ORC systems 特斯拉涡轮的动量分解分析：相位依赖滑移效应和ORC系统的设计含义

IF 10.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2026-04-01 Epub Date: 2026-02-11 DOI: 10.1016/j.enconman.2026.121189

Thongchai Kachawong, Atit Koonsrisuk

This study develops a Tesla turbine model for Organic Rankine Cycle (ORC) applications, incorporating Navier slip boundary conditions to resolve near-wall flow dynamics. Unlike previous mean-flow or constant-property formulations, the proposed parabolic-profile model resolves the laminar velocity distribution across the inter-disk gap while accounting for the property variations of organic refrigerants. Validation against experimental and CFD benchmarks demonstrates that the relative slip length (L) functions as a phase-dependent effective closure parameter, encapsulating unresolved near-wall phenomena rather than representing a directly measurable material property: vapor expansion is well-characterized by minimal slip (L ≈ 0.2, achieving 0.4% power deviation), while two-phase expansion requires higher effective slip (L ≈ 0.8, achieving negligible power deviation) to match reference data. Even without calibration, the parabolic-profile model reduces prediction errors from 17.5% (mean-flow baseline) to 4%. The validated operating range corresponds to average Reynolds numbers below 4,800. A decomposition of the momentum equations reveals a functional decoupling: the radial pressure drop is governed by an inertial penalty (centrifugal and Coriolis forces) that does not generate shaft work, while power extraction occurs exclusively through tangential viscous damping. Consequently, kinetic power from velocity reduction dominates the total output, accounting for 63–95% depending on inlet phase. Parametric sensitivity analysis exposes a 13-fold disparity in robustness: vapor expansion exhibits 13% power variation across the slip range, whereas liquid expansion varies by less than 1%, indicating that liquid-fed expanders are nearly immune to surface conditions. A robust design protocol utilizing slip envelopes is proposed to account for near-wall flow uncertainty.

本研究开发了一个用于有机朗肯循环（ORC）应用的特斯拉涡轮模型，该模型结合了纳维尔滑移边界条件来求解近壁流动动力学。与以前的平均流量或恒定性质的公式不同，提出的抛物线剖面模型解决了盘间间隙的层流速度分布，同时考虑了有机制冷剂的性质变化。对实验和CFD基准的验证表明，相对滑移长度(L)作为相位相关的有效闭合参数，封装了未解决的近壁现象，而不是代表直接可测量的材料特性：蒸汽膨胀的最小滑移（L≈0.2，实现0.4%的功率偏差）得到了很好的表征，而两相膨胀需要更高的有效滑移（L≈0.8，实现可忽略的功率偏差）来匹配参考数据。即使没有校准，抛物线剖面模型也可以将预测误差从17.5%（平均流量基线）降低到4%。验证的工作范围对应于平均雷诺数低于4800。动量方程的分解揭示了功能解耦：径向压降由惯性惩罚（离心力和科里奥利力）控制，不产生轴功，而功率提取仅通过切向粘性阻尼发生。因此，来自速度降低的动能主导了总输出，根据进口阶段的不同，占63-95%。参数敏感性分析揭示了13倍的鲁棒性差异：蒸汽膨胀在滑移范围内表现出13%的功率变化，而液体膨胀变化不到1%，这表明液体膨胀器几乎不受表面条件的影响。提出了一种利用滑移包络的鲁棒设计方案，以考虑近壁流动的不确定性。

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引用次数: 0