Pub Date : 2026-03-15Epub Date: 2026-02-10DOI: 10.1016/j.energy.2026.140413
Bingqiang Yu, Zelong Zou, Xin Zhou, Jinquan Huang, Feng Lu
Monitoring the inter-turbine temperature T43 of turbofan engines is critical for performance assessment and safety margin management. Traditional physical sensors become unreliable under extreme operating conditions, while virtual sensor methods are prone to failure when faced with model mismatch and component degradation. This paper proposes a virtual sensor for T43 by integrating rotor inertia power balance (RPB) with a physics-informed neural network (PINN). First, based on engine thermodynamics and rotor dynamics, we extract rotor inertia power as a characteristic quantity and derive an RPB-based constraint that links measurable variables to T43. The derived constraint is then embedded into the PINN training objective. Automatic differentiation is used to compute the required derivatives, and an explicit constraint form is adopted to improve numerical stability and facilitate loss balancing between the data term and the physics term. Simulations under multiple turbine degradation scenarios show that the proposed method maintains stable accuracy compared with gas-path-based and purely data-driven baselines. In our setup, an intermediate physics weight provides a favorable trade-off between physical consistency and overall loss reduction. The proposed model also achieves shorter per-step prediction time while delivering robust T43 predictions across the operating envelope.
{"title":"Physics-informed virtual sensor design for inter-turbine temperature in turbofan engines under component degradation","authors":"Bingqiang Yu, Zelong Zou, Xin Zhou, Jinquan Huang, Feng Lu","doi":"10.1016/j.energy.2026.140413","DOIUrl":"10.1016/j.energy.2026.140413","url":null,"abstract":"<div><div>Monitoring the inter-turbine temperature <em>T</em><sub>43</sub> of turbofan engines is critical for performance assessment and safety margin management. Traditional physical sensors become unreliable under extreme operating conditions, while virtual sensor methods are prone to failure when faced with model mismatch and component degradation. This paper proposes a virtual sensor for <em>T</em><sub>43</sub> by integrating rotor inertia power balance (RPB) with a physics-informed neural network (PINN). First, based on engine thermodynamics and rotor dynamics, we extract rotor inertia power as a characteristic quantity and derive an RPB-based constraint that links measurable variables to <em>T</em><sub>43</sub>. The derived constraint is then embedded into the PINN training objective. Automatic differentiation is used to compute the required derivatives, and an explicit constraint form is adopted to improve numerical stability and facilitate loss balancing between the data term and the physics term. Simulations under multiple turbine degradation scenarios show that the proposed method maintains stable accuracy compared with gas-path-based and purely data-driven baselines. In our setup, an intermediate physics weight provides a favorable trade-off between physical consistency and overall loss reduction. The proposed model also achieves shorter per-step prediction time while delivering robust <em>T</em><sub>43</sub> predictions across the operating envelope.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"347 ","pages":"Article 140413"},"PeriodicalIF":9.4,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-15Epub Date: 2026-01-19DOI: 10.1016/j.energy.2026.139919
Cao Jiongwei , Li Xiang , Wei Jiahua , Zuo Huimin , Yin Dongqin , Bao Juan , Gao Jie
Interregional power transfers have complicated coordination between local consumption and interregional export, thereby necessitating an operational framework that leverages multi-energy complementarity and coordinated source-load-storage dispatch. To that end, we developed a nested long- and short-term scheduling model for a hydro-wind-photovoltaic (PV)-thermal-pumped storage system, focusing on the Longyangxia Clean Energy Base in the upper Yellow River. The model coordinates annual reservoir operation with daily dispatch by minimizing supply-demand imbalances. The model performance was evaluated across 60 scenarios spanning typical hydrological years, generation portfolios, and local supply ratios, and three key metrics were considered: operational efficiency, supply reliability, and environmental sustainability. The results show that supplying 30 % of Qinghai's local demand achieved a preferable balance between total generation, renewable integration, reliability, and transmission-corridor utilization, with annual generation of 69.42, 69.59, and 68.39 TWh in wet, normal, and dry years, respectively. Wind and PV curtailment remained at 2.00 %–2.60 % and the probability of load loss was 7.80 %–16.60 %. Thermal power offered limited flexibility, while hydropower and pumped storage provided higher support for wind and PV integration. Moreover, pumped storage operated for over 4600 h per year, contributing more than 30 % of daily peak shaving with a levelized storage cost of 0.35 CNY/kWh. Therefore, moderately expanding the Longyangxia hydropower units' installed capacity and accelerating pumped-storage deployment will strengthen peak-shaving and frequency-regulation capabilities. The proposed nested scheduling and multi-scenario evaluation framework lays a quantitative foundation for the planning and operation of similar clean energy bases.
{"title":"Improving PV-wind power utilization by thermal, hydro and pumped storage considering local and cross-regional power demand","authors":"Cao Jiongwei , Li Xiang , Wei Jiahua , Zuo Huimin , Yin Dongqin , Bao Juan , Gao Jie","doi":"10.1016/j.energy.2026.139919","DOIUrl":"10.1016/j.energy.2026.139919","url":null,"abstract":"<div><div>Interregional power transfers have complicated coordination between local consumption and interregional export, thereby necessitating an operational framework that leverages multi-energy complementarity and coordinated source-load-storage dispatch. To that end, we developed a nested long- and short-term scheduling model for a hydro-wind-photovoltaic (PV)-thermal-pumped storage system, focusing on the Longyangxia Clean Energy Base in the upper Yellow River. The model coordinates annual reservoir operation with daily dispatch by minimizing supply-demand imbalances. The model performance was evaluated across 60 scenarios spanning typical hydrological years, generation portfolios, and local supply ratios, and three key metrics were considered: operational efficiency, supply reliability, and environmental sustainability. The results show that supplying 30 % of Qinghai's local demand achieved a preferable balance between total generation, renewable integration, reliability, and transmission-corridor utilization, with annual generation of 69.42, 69.59, and 68.39 TWh in wet, normal, and dry years, respectively. Wind and PV curtailment remained at 2.00 %–2.60 % and the probability of load loss was 7.80 %–16.60 %. Thermal power offered limited flexibility, while hydropower and pumped storage provided higher support for wind and PV integration. Moreover, pumped storage operated for over 4600 h per year, contributing more than 30 % of daily peak shaving with a levelized storage cost of 0.35 CNY/kWh. Therefore, moderately expanding the Longyangxia hydropower units' installed capacity and accelerating pumped-storage deployment will strengthen peak-shaving and frequency-regulation capabilities. The proposed nested scheduling and multi-scenario evaluation framework lays a quantitative foundation for the planning and operation of similar clean energy bases.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"347 ","pages":"Article 139919"},"PeriodicalIF":9.4,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-15Epub Date: 2026-01-21DOI: 10.1016/j.energy.2026.140129
Zhuang Shao , Yushan Liu , Binyao Zheng, Jing Zhao
The transformation of urban energy systems under low-carbon constraints poses profound challenges for megacities, where rapid demand growth and limited local generation capacity often lead to structural imbalances between supply and demand. Using Beijing as a representative case, a refined Low Emission Analysis Platform (LEAP) framework was established to simulate 4 policy and 2 integrated scenarios during 2023–2060, examining how demand growth, supply decarbonization, and systemic resilience co-evolve. This study quantifies the critical supply–demand synergy threshold at the city scale, proposes a staged and temporally explicit decarbonization roadmap, and demonstrates that the energy transition is a dynamic and path-dependent process rather than a linear shift toward carbon neutrality. Specifically, total energy demand peaks around 2030 and then gradually declines, with renewables progressively replacing fossil-based generation to raise the share of non-fossil electricity above 70 % by 2060. The integrated Green Transport–Carbon Capture, Utilization and Storage (GT–CCUS) scenario achieves the earliest and deepest emission reductions, confirming that only the joint advancement of demand-side electrification and supply-side decarbonization—especially through large-scale renewables and CCUS as buffering mechanisms when renewables exceed roughly 50 % of the power mix—produces the most substantive system-wide benefits. Beyond emissions, the findings highlight that decarbonization can advance only upon a stable foundation of energy security and systemic resilience. As electrification accelerates, tensions between expanding demand and constrained supply may evolve from synergy to trade-off, and ultimately to antagonism if not managed adaptively. Ensuring a balanced transition therefore requires reinforcing grid flexibility, local generation reliability, and institutional adaptability to prevent systemic stress from undermining long-term climate goals. Beijing's experience proves that low-carbon development is not merely a technological substitution but a continual process of negotiating stability, efficiency, and sustainability within an increasingly interdependent urban energy system.
{"title":"Exploring carbon peak and carbon neutrality pathways for megacities from the perspective of supply and demand synergy: A LEAP simulation of the Beijing case","authors":"Zhuang Shao , Yushan Liu , Binyao Zheng, Jing Zhao","doi":"10.1016/j.energy.2026.140129","DOIUrl":"10.1016/j.energy.2026.140129","url":null,"abstract":"<div><div>The transformation of urban energy systems under low-carbon constraints poses profound challenges for megacities, where rapid demand growth and limited local generation capacity often lead to structural imbalances between supply and demand. Using Beijing as a representative case, a refined Low Emission Analysis Platform (LEAP) framework was established to simulate 4 policy and 2 integrated scenarios during 2023–2060, examining how demand growth, supply decarbonization, and systemic resilience co-evolve. This study quantifies the critical supply–demand synergy threshold at the city scale, proposes a staged and temporally explicit decarbonization roadmap, and demonstrates that the energy transition is a dynamic and path-dependent process rather than a linear shift toward carbon neutrality. Specifically, total energy demand peaks around 2030 and then gradually declines, with renewables progressively replacing fossil-based generation to raise the share of non-fossil electricity above 70 % by 2060. The integrated Green Transport–Carbon Capture, Utilization and Storage (GT–CCUS) scenario achieves the earliest and deepest emission reductions, confirming that only the joint advancement of demand-side electrification and supply-side decarbonization—especially through large-scale renewables and CCUS as buffering mechanisms when renewables exceed roughly 50 % of the power mix—produces the most substantive system-wide benefits. Beyond emissions, the findings highlight that decarbonization can advance only upon a stable foundation of energy security and systemic resilience. As electrification accelerates, tensions between expanding demand and constrained supply may evolve from synergy to trade-off, and ultimately to antagonism if not managed adaptively. Ensuring a balanced transition therefore requires reinforcing grid flexibility, local generation reliability, and institutional adaptability to prevent systemic stress from undermining long-term climate goals. Beijing's experience proves that low-carbon development is not merely a technological substitution but a continual process of negotiating stability, efficiency, and sustainability within an increasingly interdependent urban energy system.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"347 ","pages":"Article 140129"},"PeriodicalIF":9.4,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-15Epub Date: 2026-02-04DOI: 10.1016/j.energy.2026.140204
Hanyu Wang , Shuichiro Miwa , Wen Zhou , Ryo Yokoyama , Koji Okamoto
High-fidelity void-fraction signals constitute essential data for modeling two-phase flows. However, the scarcity of such data constrains the development and validation of high-accuracy models, thereby impeding the design and optimization of complex industrial systems, including nuclear reactors and other energy facilities. To address this challenge, this study proposes a novel database enhancement framework, termed VoidGAN, based on conditional generative adversarial networks (GANs). The proposed model integrates Transformer modules with multi-scale convolutional Inception blocks, enabling it to capture both long-term temporal dependencies and local, irregular fluctuations. In addition, a physics-metrics-guided Bayesian hyperparameter optimization strategy is introduced to enhance the physical fidelity of the generated signals. A comprehensive multi-step validation framework is further established to rigorously assess the reliability of the generated data, encompassing direct comparisons with testing datasets and benchmarking against established mechanistic models, including the two-group drift-flux model and the two-phase flow-induced vibration (TP-FIV) excited force model. The results demonstrate that VoidGAN achieves the best overall performance among state-of-the-art time-series generative models, attaining a recall exceeding 99.8%, achieving the lowest nearest-neighbor distance (0.069), and maintaining inference times at the millisecond scale. These results confirm that both time-averaged and temporal characteristics, as well as their intricate relationships across diverse flow regimes, are accurately captured. This work provides a new perspective for mitigating data scarcity issues in two-phase flow modeling and paves the way for more efficient design and optimization of industrial systems.
{"title":"VoidGAN: A generative adversarial network for high-fidelity void fraction signal generation in nuclear reactor thermal hydraulics","authors":"Hanyu Wang , Shuichiro Miwa , Wen Zhou , Ryo Yokoyama , Koji Okamoto","doi":"10.1016/j.energy.2026.140204","DOIUrl":"10.1016/j.energy.2026.140204","url":null,"abstract":"<div><div>High-fidelity void-fraction signals constitute essential data for modeling two-phase flows. However, the scarcity of such data constrains the development and validation of high-accuracy models, thereby impeding the design and optimization of complex industrial systems, including nuclear reactors and other energy facilities. To address this challenge, this study proposes a novel database enhancement framework, termed VoidGAN, based on conditional generative adversarial networks (GANs). The proposed model integrates Transformer modules with multi-scale convolutional Inception blocks, enabling it to capture both long-term temporal dependencies and local, irregular fluctuations. In addition, a physics-metrics-guided Bayesian hyperparameter optimization strategy is introduced to enhance the physical fidelity of the generated signals. A comprehensive multi-step validation framework is further established to rigorously assess the reliability of the generated data, encompassing direct comparisons with testing datasets and benchmarking against established mechanistic models, including the two-group drift-flux model and the two-phase flow-induced vibration (TP-FIV) excited force model. The results demonstrate that VoidGAN achieves the best overall performance among state-of-the-art time-series generative models, attaining a recall exceeding 99.8%, achieving the lowest nearest-neighbor distance (0.069), and maintaining inference times at the millisecond scale. These results confirm that both time-averaged and temporal characteristics, as well as their intricate relationships across diverse flow regimes, are accurately captured. This work provides a new perspective for mitigating data scarcity issues in two-phase flow modeling and paves the way for more efficient design and optimization of industrial systems.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"347 ","pages":"Article 140204"},"PeriodicalIF":9.4,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-15Epub Date: 2026-02-05DOI: 10.1016/j.energy.2026.140322
Ching-Wen Lo , Po-Yao Syu , Chen-Kuang Wang , Ya-Yu Chiang
This study investigates the influence of helix structure arrays on saturated pool boiling performance through a systematic parametric evaluation of helix height and density. A total of seven copper-based surfaces, including one flat baseline and six helix-structured configurations, were tested in distilled water under atmospheric pressure. The results demonstrate that appropriately designed helix structures can simultaneously enhance the critical heat flux (CHF) and the heat transfer coefficient (HTC) by up to 78% and 164%, respectively. These enhancements are attributed to the combined effects of shortened bubble residence time, increased bubble departure height, and intensified local convective flow fields. High-speed imaging revealed that taller helix arrays facilitate vapor column detachment and reduce vapor accumulation above the heated surface, while particle image velocimetry (PIV) confirmed the presence of accelerated upward fluid motion induced by vapor ejection and capillary-driven liquid return. These findings underscore the critical role of helix geometry in manipulating interfacial bubble dynamics and promoting liquid–vapor separation, offering promising insights for the thermal design of advanced boiling surfaces.
{"title":"Manipulating bubble departure by varying helix structure heights to enhance pool boiling heat transfer","authors":"Ching-Wen Lo , Po-Yao Syu , Chen-Kuang Wang , Ya-Yu Chiang","doi":"10.1016/j.energy.2026.140322","DOIUrl":"10.1016/j.energy.2026.140322","url":null,"abstract":"<div><div>This study investigates the influence of helix structure arrays on saturated pool boiling performance through a systematic parametric evaluation of helix height and density. A total of seven copper-based surfaces, including one flat baseline and six helix-structured configurations, were tested in distilled water under atmospheric pressure. The results demonstrate that appropriately designed helix structures can simultaneously enhance the critical heat flux (CHF) and the heat transfer coefficient (HTC) by up to 78% and 164%, respectively. These enhancements are attributed to the combined effects of shortened bubble residence time, increased bubble departure height, and intensified local convective flow fields. High-speed imaging revealed that taller helix arrays facilitate vapor column detachment and reduce vapor accumulation above the heated surface, while particle image velocimetry (PIV) confirmed the presence of accelerated upward fluid motion induced by vapor ejection and capillary-driven liquid return. These findings underscore the critical role of helix geometry in manipulating interfacial bubble dynamics and promoting liquid–vapor separation, offering promising insights for the thermal design of advanced boiling surfaces.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"347 ","pages":"Article 140322"},"PeriodicalIF":9.4,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-15Epub Date: 2026-02-02DOI: 10.1016/j.energy.2026.140299
Santi Bardeeniz , Chayanit Chuay-ock , David Shan-Hill Wong , Yuan Yao , Jia-Lin Kang , Chanin Panjapornpon
Effective steam management supports cost control and carbon abatement in industrial processes. However, steam monitoring in industrial records often exhibits mixed sampling intervals. The mismatch in time interval creates a limited-data problem that conventional energy models often struggle to handle. Therefore, a model-agnostic meta-learning framework integrated with an attention-based long short-term memory network is proposed for steam-consumption prediction under limited-data conditions. Meta-training on related high-frequency source units learns shared attention parameters and enables rapid adaptation to a low-frequency target unit without requiring synthetic data generation. The performance of steam consumption prediction is validated using a large-scale case study of the crude glycerin purification process. The results demonstrate that the attention-based long short-term memory model outperforms traditional models with the highest coefficient of determination value (R2) of 0.772. The incorporation of meta-learning further enhances the prediction performance of the model, with a decrease in the prediction error from 168.891 to 123.777 kg/h and an improvement in R2 of 0.847. Furthermore, the energy-saving analysis indicates the reduction in annual steam consumption and greenhouse gas emissions of 4372.304 (11.63% reduction) and 613.815 tons, respectively.
{"title":"Mixed-interval steam consumption modeling for industrial energy optimization via meta-learning through shared attention","authors":"Santi Bardeeniz , Chayanit Chuay-ock , David Shan-Hill Wong , Yuan Yao , Jia-Lin Kang , Chanin Panjapornpon","doi":"10.1016/j.energy.2026.140299","DOIUrl":"10.1016/j.energy.2026.140299","url":null,"abstract":"<div><div>Effective steam management supports cost control and carbon abatement in industrial processes. However, steam monitoring in industrial records often exhibits mixed sampling intervals. The mismatch in time interval creates a limited-data problem that conventional energy models often struggle to handle. Therefore, a model-agnostic meta-learning framework integrated with an attention-based long short-term memory network is proposed for steam-consumption prediction under limited-data conditions. Meta-training on related high-frequency source units learns shared attention parameters and enables rapid adaptation to a low-frequency target unit without requiring synthetic data generation. The performance of steam consumption prediction is validated using a large-scale case study of the crude glycerin purification process. The results demonstrate that the attention-based long short-term memory model outperforms traditional models with the highest coefficient of determination value (R<sup>2</sup>) of 0.772. The incorporation of meta-learning further enhances the prediction performance of the model, with a decrease in the prediction error from 168.891 to 123.777 kg/h and an improvement in R<sup>2</sup> of 0.847. Furthermore, the energy-saving analysis indicates the reduction in annual steam consumption and greenhouse gas emissions of 4372.304 (11.63% reduction) and 613.815 tons, respectively.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"347 ","pages":"Article 140299"},"PeriodicalIF":9.4,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-15Epub Date: 2026-02-10DOI: 10.1016/j.energy.2026.140423
Jae Hyun Kim, Tae Won Kim, Oh Chae Kwon
To facilitate the use of ammonia (NH3) combustion in industrial burners, the combustion characteristics of nonpremixed NH3-hydrogen (H2)-nitrogen (N2)/air coaxial flames at elevated inlet gas temperature (Tin) and chamber pressure (P) in a model combustor are studied under varying hydrogen mole fraction (xh,f), fuel-equivalence ratio (ϕ) and fuel Reynolds number (Ref) conditions. Increasing P and Tin each exert opposite effects on the combustion characteristics of the nonpremixed flames. Increasing P shrinks fuel-lean limits, decreases nitrogen oxides (NOx) emissions, increases unburned NH3 emissions and shifts the main reaction zone upstream and thus local extinction to occur near the flame base. Meanwhile, increasing Tin at given Ref expands the fuel-lean limits in terms of xh,f, increases NOx emissions, decreases unburned NH3 emissions and causes local extinction to primarily occur near a breakpoint due to the increased flow velocity. When P and Tin increase simultaneously, NOx and NH3 emissions exhibit the same trends as a function of ϕ as observed when each parameter is varied individually. Conditions with relatively low and nearly 1:1 NOx and unburned NH3 emissions are identified (approximately 490 ppm at ϕ = 0.6, xh,f = 0.50, P = 4.0 bar and Tin = 600 K), providing favorable conditions for the application of a selective catalytic reduction (SCR) system.
{"title":"Combustion characteristics of nonpremixed ammonia-hydrogen/air coaxial flames at elevated temperature and pressure in a model combustor","authors":"Jae Hyun Kim, Tae Won Kim, Oh Chae Kwon","doi":"10.1016/j.energy.2026.140423","DOIUrl":"10.1016/j.energy.2026.140423","url":null,"abstract":"<div><div>To facilitate the use of ammonia (NH<sub>3</sub>) combustion in industrial burners, the combustion characteristics of nonpremixed NH<sub>3</sub>-hydrogen (H<sub>2</sub>)-nitrogen (N<sub>2</sub>)/air coaxial flames at elevated inlet gas temperature (<em>T</em><sub>in</sub>) and chamber pressure (<em>P</em>) in a model combustor are studied under varying hydrogen mole fraction (<em>x</em><sub>h,f</sub>), fuel-equivalence ratio (<em>ϕ</em>) and fuel Reynolds number (Re<sub>f</sub>) conditions. Increasing <em>P</em> and <em>T</em><sub>in</sub> each exert opposite effects on the combustion characteristics of the nonpremixed flames. Increasing <em>P</em> shrinks fuel-lean limits, decreases nitrogen oxides (NO<sub>x</sub>) emissions, increases unburned NH<sub>3</sub> emissions and shifts the main reaction zone upstream and thus local extinction to occur near the flame base. Meanwhile, increasing <em>T</em><sub>in</sub> at given Re<sub>f</sub> expands the fuel-lean limits in terms of <em>x</em><sub>h,f</sub>, increases NO<sub>x</sub> emissions, decreases unburned NH<sub>3</sub> emissions and causes local extinction to primarily occur near a breakpoint due to the increased flow velocity. When <em>P</em> and <em>T</em><sub>in</sub> increase simultaneously, NO<sub>x</sub> and NH<sub>3</sub> emissions exhibit the same trends as a function of <em>ϕ</em> as observed when each parameter is varied individually. Conditions with relatively low and nearly 1:1 NO<sub>x</sub> and unburned NH<sub>3</sub> emissions are identified (approximately 490 ppm at <em>ϕ</em> = 0.6, <em>x</em><sub>h,f</sub> = 0.50, <em>P</em> = 4.0 bar and <em>T</em><sub>in</sub> = 600 K), providing favorable conditions for the application of a selective catalytic reduction (SCR) system.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"347 ","pages":"Article 140423"},"PeriodicalIF":9.4,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-15Epub Date: 2026-02-09DOI: 10.1016/j.energy.2026.140378
Hua Yang , Jiachao Wu, Jingyu Cui, Cong Du, Liang Tian, Fuxing Zhao
Compressed air energy storage (CAES) is a promising solution for large-scale energy storage. This study develops a three-stage compression and two-stage expansion thermal-storage CAES (TS-CAES) system with abandoned oil well (AOW) storage. Simulation results show: (1) During the energy storage stage, the underground well (UG) achieves the fastest pressure buildup rate, reaching 15 MPa in 6.3 h, 1.0 h faster than the first on-ground tank (OG1) and 1.6 h faster than the second on-ground tank (OG2); (2) During the energy release stage, UG maintains the most stable internal temperature, with an energy release duration of 4.2 h, shorter than OG1 (4.5 h) and OG2 (5.3 h), thus ensuring stable turbine inlet conditions; (3) UG benefits from geothermal coupling with surrounding strata (343 K), which accelerates pressurization, stabilizes discharge, and enables the highest recoverable waste heat (6.95 × 104 MJ), surpassing OG1 and OG2 by over 10%. This geothermal contribution transforms the UG chamber from a passive air reservoir into an active energy conversion component. This study confirms the feasibility of using abandoned oil well as alternative air storage tanks (ASTs) in TS-CAES systems, providing theoretical support for their integration with geothermal resources to optimize large-scale energy storage performance.
{"title":"Dynamic characteristics of compressed air energy storage system embedded with abandoned oil well storage: A numerical approach","authors":"Hua Yang , Jiachao Wu, Jingyu Cui, Cong Du, Liang Tian, Fuxing Zhao","doi":"10.1016/j.energy.2026.140378","DOIUrl":"10.1016/j.energy.2026.140378","url":null,"abstract":"<div><div>Compressed air energy storage (CAES) is a promising solution for large-scale energy storage. This study develops a three-stage compression and two-stage expansion thermal-storage CAES (TS-CAES) system with abandoned oil well (AOW) storage. Simulation results show: (1) During the energy storage stage, the underground well (UG) achieves the fastest pressure buildup rate, reaching 15 MPa in 6.3 h, 1.0 h faster than the first on-ground tank (OG1) and 1.6 h faster than the second on-ground tank (OG2); (2) During the energy release stage, UG maintains the most stable internal temperature, with an energy release duration of 4.2 h, shorter than OG1 (4.5 h) and OG2 (5.3 h), thus ensuring stable turbine inlet conditions; (3) UG benefits from geothermal coupling with surrounding strata (343 K), which accelerates pressurization, stabilizes discharge, and enables the highest recoverable waste heat (6.95 × 10<sup>4</sup> MJ), surpassing OG1 and OG2 by over 10%. This geothermal contribution transforms the UG chamber from a passive air reservoir into an active energy conversion component. This study confirms the feasibility of using abandoned oil well as alternative air storage tanks (ASTs) in TS-CAES systems, providing theoretical support for their integration with geothermal resources to optimize large-scale energy storage performance.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"347 ","pages":"Article 140378"},"PeriodicalIF":9.4,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-15Epub Date: 2026-02-07DOI: 10.1016/j.energy.2026.140350
Yanli Feng, Enbo Zhang, Bofeng Bai
The supercritical carbon dioxide (S-CO2) radial inflow turbine (RIT) is a critical component in advanced power cycles. However, its design is challenged by the complexity of thermophysical properties of S-CO2 and the interdependent nature of key empirical parameters. This study establishes a robust one-dimensional aero-thermodynamic design methodology for S-CO2 RITs, integrating an optimized loss model correlation with the Particle Swarm Optimization (PSO) algorithm. The PSO algorithm was then employed to automate the synergistic optimization of five critical dimensionless parameters: reaction degree, flow coefficient, velocity ratio, incidence angle, and radius ratio. The application of this framework to a 350 kW case study demonstrated a significant performance enhancement, achieving a 1.67% increase in total-static efficiency and a 2.03% gain in output power compared to a baseline design. Flow field analysis revealed that the optimized design, characterized by a higher reaction degree and increased blade height, effectively suppresses tip leakage flow and mitigates the adverse coupling between tip leakage vortices (TLVs) and secondary flows by leveraging controlled vortex interactions. This mechanism fundamentally reduces passage and clearance losses, thereby validating the proposed multi-parameter optimization approach as a powerful tool for the high-performance design of S-CO2 RITs.
{"title":"The aero-thermodynamic design of supercritical CO2 radial turbine based on the particle swarm optimization and vortex competitive mechanism","authors":"Yanli Feng, Enbo Zhang, Bofeng Bai","doi":"10.1016/j.energy.2026.140350","DOIUrl":"10.1016/j.energy.2026.140350","url":null,"abstract":"<div><div>The supercritical carbon dioxide (S-CO<sub>2</sub>) radial inflow turbine (RIT) is a critical component in advanced power cycles. However, its design is challenged by the complexity of thermophysical properties of S-CO<sub>2</sub> and the interdependent nature of key empirical parameters. This study establishes a robust one-dimensional aero-thermodynamic design methodology for S-CO<sub>2</sub> RITs, integrating an optimized loss model correlation with the Particle Swarm Optimization (PSO) algorithm. The PSO algorithm was then employed to automate the synergistic optimization of five critical dimensionless parameters: reaction degree, flow coefficient, velocity ratio, incidence angle, and radius ratio. The application of this framework to a 350 kW case study demonstrated a significant performance enhancement, achieving a 1.67% increase in total-static efficiency and a 2.03% gain in output power compared to a baseline design. Flow field analysis revealed that the optimized design, characterized by a higher reaction degree and increased blade height, effectively suppresses tip leakage flow and mitigates the adverse coupling between tip leakage vortices (TLVs) and secondary flows by leveraging controlled vortex interactions. This mechanism fundamentally reduces passage and clearance losses, thereby validating the proposed multi-parameter optimization approach as a powerful tool for the high-performance design of S-CO<sub>2</sub> RITs.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"347 ","pages":"Article 140350"},"PeriodicalIF":9.4,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lithium-ion batteries (LiBs) are central to modern electric mobility, yet accurate health prediction remains challenging due to nonlinear degradation, thermal variability, and noisy operational data. This study presents a novel hybrid framework—the Lotus-based Radial Basis Function (LbRBF) model—which integrates the bio-inspired Lotus Optimization Algorithm (LOA) with Radial Basis Function Neural Networks (RBFNNs) for intelligent, adaptive, and computationally efficient battery health prediction. Trained on real-world NASA and Oxford EV battery datasets, LbRBF achieved an R2 of 0.988, RMSE of 9.90%, and MAE of 0.49%, outperforming state-of-the-art models such as LSTM, CNN, and SVM by up to 12.5% in prediction accuracy. The model demonstrates high computational efficiency, achieving 730 inferences/s with only 3.6 × 105 FLOPs, indicating suitability for low-latency applications. Although experimental validation was conducted on an Intel i7 CPU and NVIDIA RTX 3060 GPU, the low computational complexity suggests promising adaptability to resource-constrained embedded BMS platforms, pending dedicated hardware-level validation. Additionally, SHAP-based explainability provides insights into dominant degradation factors, including temperature and overcharge rate, improving model transparency. By combining high predictive accuracy, energy-efficient operation, and interpretability, the proposed LbRBF framework offers a scalable solution for next-generation electric vehicles and smart energy storage systems, enabling proactive battery management, optimized charging strategies, and extended battery lifespan.
{"title":"A lotus-optimized Radial basis function framework for explainable and energy-efficient battery health prediction in electric vehicles","authors":"Hemanthasai Madugula , Aishvaria Gorityala , Sujit Singh , Venkata Reddy Muppani , Sudha Radhika","doi":"10.1016/j.energy.2026.140419","DOIUrl":"10.1016/j.energy.2026.140419","url":null,"abstract":"<div><div>Lithium-ion batteries (LiBs) are central to modern electric mobility, yet accurate health prediction remains challenging due to nonlinear degradation, thermal variability, and noisy operational data. This study presents a novel hybrid framework—the Lotus-based Radial Basis Function (LbRBF) model—which integrates the bio-inspired Lotus Optimization Algorithm (LOA) with Radial Basis Function Neural Networks (RBFNNs) for intelligent, adaptive, and computationally efficient battery health prediction. Trained on real-world NASA and Oxford EV battery datasets, LbRBF achieved an R<sup>2</sup> of 0.988, RMSE of 9.90%, and MAE of 0.49%, outperforming state-of-the-art models such as LSTM, CNN, and SVM by up to 12.5% in prediction accuracy. The model demonstrates high computational efficiency, achieving 730 inferences/s with only 3.6 × 10<sup>5</sup> FLOPs, indicating suitability for low-latency applications<strong>.</strong> Although experimental validation was conducted on an Intel i7 CPU and NVIDIA RTX 3060 GPU, the low computational complexity suggests promising adaptability to resource-constrained embedded BMS platforms, pending dedicated hardware-level validation. Additionally, SHAP-based explainability provides insights into dominant degradation factors, including temperature and overcharge rate, improving model transparency. By combining high predictive accuracy, energy-efficient operation, and interpretability, the proposed LbRBF framework offers a scalable solution for next-generation electric vehicles and smart energy storage systems, enabling proactive battery management, optimized charging strategies, and extended battery lifespan.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"347 ","pages":"Article 140419"},"PeriodicalIF":9.4,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}