Energy Science & Engineering最新文献

{"title":"Daily Residential Natural Gas Demand Forecasting Using Machine Learning Regression: Comparative Evaluation With a Case Study in Qazvin Province, Iran","authors":"Ali Pirzad,&nbsp;Mostafa Khanzadi","doi":"10.1002/ese3.70550","DOIUrl":"https://doi.org/10.1002/ese3.70550","url":null,"abstract":"<p>Accurate short-term forecasting of residential natural gas consumption (NGC) is essential for operational planning and supply reliability. Most forecasting studies rely primarily on meteorological variables, often neglecting infrastructure expansion effects. This study introduces the subscription growth ratio (SGR) as a socioeconomic indicator to enhance daily residential NGC forecasting in Qazvin Province, Iran. Two datasets were developed: Dataset A containing meteorological variables and Dataset A + SGR incorporating subscription growth information. Forecasting performance was evaluated using expanding window cross-validation across 52 sequential folds. Multiple regression models were implemented, including multiple linear regression (MLR), support vector regression (SVR), random forest regression (RFR), and XGBoost (XGB). Feature importance analysis confirmed that temperature variables dominate NGC variation; however, SGR ranked as the third most influential predictor, exceeding maximum temperature. Results show that incorporating SGR significantly improves nonlinear model performance, reducing MAE by approximately 20% in RFR and XGB and increasing adjusted <i>R</i>² by about 38%. Paired hypothesis testing confirmed statistically significant improvements for SVR (<i>p</i> &lt; 0.001), RFR (<i>p</i> = 0.000347), and XGB (<i>p</i> = 0.012654), while MLR showed no significant improvement (<i>p</i> = 0.767816). The findings demonstrate that infrastructure-driven demand growth has a nonlinear influence on residential NGC and should be integrated into operational forecasting frameworks.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"14 8","pages":"3656-3673"},"PeriodicalIF":3.6,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.70550","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148699920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Tunnel Ventilation on Hydrogen Dispersion From Leaks in Hydrogen Fuel Cell Trucks","authors":"Limin Geng,&nbsp;Shiyu Shan,&nbsp;Zongxue Yan,&nbsp;Nan Gao,&nbsp;Dong Huang,&nbsp;Zhao Gao,&nbsp;Xinxin Cao","doi":"10.1002/ese3.70547","DOIUrl":"https://doi.org/10.1002/ese3.70547","url":null,"abstract":"<p>The widespread adoption of hydrogen fuel cell trucks (HFCTs) depends on addressing hydrogen safety concerns, particularly in confined spaces like tunnels, where effective ventilation is crucial to prevent accumulation during leaks. This study uses a computational fluid dynamics (CFD) model to simulate hydrogen dispersion and evaluates key ventilation factors—velocity, area, placement, and spacing. An orthogonal sensitivity analysis identifies vent area as the dominant parameter, leading to the optimal ventilation strategy. The results confirm that increasing ventilation velocity and vent cross-sectional area significantly improve hydrogen exhaust efficiency. Specifically, increasing ventilation velocity from 5 to 20 m/s reduced the flammable cloud volume by 55.35%, while expanding the vent area from 1 to 4 m² reduced it by 49.62%. The vent cross-sectional area was identified as the most influential parameter. Furthermore, top-mounted vent placement proved more effective than sidewall configurations, and a 50 m longitudinal spacing outperformed 100 m in minimizing the hydrogen cloud. Consequently, the optimal ventilation configuration is a system with a velocity of 20 m/s, top-mounted vents, a cross-sectional area of 4 m², and 50 m spacing.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"14 8","pages":"3608-3624"},"PeriodicalIF":3.6,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.70547","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148700105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Investigation on Steam Generation Performance of a Solid Thermal Storage-Based Steam Production System","authors":"Sun Yong,&nbsp;Liu Sai,&nbsp;Liu Congcong,&nbsp;Yang Chunhui,&nbsp;Yao Xinyu,&nbsp;Zhang Yujin","doi":"10.1002/ese3.70572","DOIUrl":"https://doi.org/10.1002/ese3.70572","url":null,"abstract":"<p>This study presents the construction and experimental investigation of a solid thermal storage-based steam production system, which primarily consists of a solid heat storage unit, a steam generator, a feedwater system, and an electric heating device. Steam generation performance was evaluated under different experimental operating conditions, and operational parameters of each component were recorded. The results indicate that under constant initial conditions and steam flow rate, the system can stably produce steam at 0.2 MPa for 254 min, with the lowest steam-generating temperature of the storage medium reaching 321.21°C and a system efficiency (<i>η</i>) of 54.37%. When producing steam at 0.5 MPa, the system operates for 199 min, with a minimum storage medium temperature of 358.41°C and an efficiency of 47.47%. An increase of 41.9 kJ/kg in the outlet steam enthalpy results in a 21.65% reduction in system operating time. The fluctuation of steam parameters under all tested conditions remained below 10%, demonstrating the system's capability for stable steam production. Furthermore, the study shows that the time required for the system to reach the target steam parameters from startup is influenced by the heat release power of the storage medium and the outlet steam parameters. Specifically, when the steam pressure is increased from 0.2 to 0.5 MPa, the system startup duration increases by 30.9%.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"14 8","pages":"3906-3921"},"PeriodicalIF":3.6,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.70572","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148699854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Environmental Thermoeconomic Performance Analysis of Gas Steam Combined Cycle With Different Inlet Air Cooling Technologies","authors":"Zhen Wang,&nbsp;Li Zhang,&nbsp;Yu Ni,&nbsp;Liqiang Duan","doi":"10.1002/ese3.70549","DOIUrl":"https://doi.org/10.1002/ese3.70549","url":null,"abstract":"<p>The increase in inlet air temperature significantly reduces the efficiency of gas–steam combined cycle (GSCC) system, a problem that becomes particularly pronounced in high-temperature environment. Selecting an appropriate inlet air cooling (IAC) technology is of great importance for enhancing system performance. In order to comprehensive reveal the characteristics of the IAC technology, this study establishes an environmental thermoeconomic cost (ETC) model to investigate the impact of two IAC technologies, including absorption refrigeration cooling (ARC) and spray evaporative cooling (SEC), on the performance of a GSCC from three aspects of energy, economy, and environment (3E). The results show that the IAC technology can effectively reduce the impact of ambient temperature on the system environmental thermoeconomic performance. For the ARC technology, the cooling effectiveness improves with increasing ambient temperature, leading to a maximum ETC reduction of 3.6%. For the SEC technology, the cooling effectiveness is more significantly affected by relative humidity (RH) as ambient temperature increases, with a maximum cost reduction of 0.64% for every 10% decrease in RH. Under arid climate conditions, the SEC technology demonstrates superior performance in terms of cost-effectiveness and environmental impact. Conversely, in high-humidity environment, the ARC technology provides the greatest enhancement in GSCC performance. This research provides scientific support for selecting cooling methods under different environmental conditions, and offers practical significance for optimizing the GSCC operational performance.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"14 8","pages":"3638-3655"},"PeriodicalIF":3.6,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.70549","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148699884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temperature Coefficient Analysis of Polycrystalline PV Modules Under Field Conditions in Ghana","authors":"Emmanuel Akono Sarsah,&nbsp;Abdul-Rahim Bawa","doi":"10.1002/ese3.70566","DOIUrl":"https://doi.org/10.1002/ese3.70566","url":null,"abstract":"<p>Photovoltaic (PV) systems in tropical climates routinely operate at temperatures well above standard test conditions (STC), yet field-measured temperature coefficients remain scarce for sub-Saharan Africa. This study quantifies the temperature coefficient of maximum power (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <msub>\u0000 <mi>β</mi>\u0000 \u0000 <msub>\u0000 <mi>P</mi>\u0000 \u0000 <mi>max</mi>\u0000 </msub>\u0000 </msub>\u0000 </mrow>\u0000 </mrow>\u0000 </semantics></math>) for a 163.52 kWp polycrystalline silicon array at the Kaleo Solar Farm (KSF) in northern Ghana, using 14 months of high-resolution field data. Module temperature was estimated using a nominal operating cell temperature (NOCT) model and a performance ratio (PR) based regression was applied to near-STC records. The field-measured <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <msub>\u0000 <mi>β</mi>\u0000 \u0000 <msub>\u0000 <mi>P</mi>\u0000 \u0000 <mi>max</mi>\u0000 </msub>\u0000 </msub>\u0000 </mrow>\u0000 </mrow>\u0000 </semantics></math> was −0.473%/°C (95% CI: −0.883 to −0.063%/°C), approximately 31% more negative than the manufacturer's datasheet value of −0.36%/°C. Mean daytime module temperature reached 46°C, with peaks up to 72°C, confirming sustained thermal stress beyond STC. An annual energy yield simulation showed that the field-measured coefficient implies approximately 7761 kWh/year more energy loss than predicted by the datasheet value—a deficit consistent with the accelerated degradation rates and shortened service lives reported for PV systems across West Africa. These findings demonstrate that manufacturer temperature coefficients systematically underestimate thermal losses in tropical field environments and highlight the need for region-specific performance standards and design tools that incorporate field-measured coefficients.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"14 8","pages":"3878-3888"},"PeriodicalIF":3.6,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.70566","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148699838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Real-Time Incremental Learning Artificial Neural Networks Maximum Power Point Tracking With Raspberry Pi-Based Meteorological Data Acquisition","authors":"Rida Amine,&nbsp;Noureddine El Barbri,&nbsp;Mourad Yessef,&nbsp;Mohammed M. Alammar,&nbsp;Z.M.S. El-Barbary,&nbsp;Hatim Ameziane","doi":"10.1002/ese3.70555","DOIUrl":"https://doi.org/10.1002/ese3.70555","url":null,"abstract":"<p>This paper presents a new maximum power point tracking (MPPT) method for photovoltaic (PV) systems based on artificial neural networks (ANNs) models integrated with incremental learning and the capability of real-time acquiring meteorological conditions by using a Raspberry Pi. The approach uses hourly irradiance and temperature values obtained from the NASA POWER API to dynamically re-train the ANN model according to weather conditions. Simulation results using MATLAB/Simulink reveal that the proposed system exhibits high precision and robust performance over a range of irradiance (200–1000 W/m²). The system achieved an average PV conversion efficiency of 99.52% and load-side efficiency of 98.50%, outperforming several conventional and intelligent MPPT techniques reported in the literature. Performance quantification results in an MSE of 0.0024 and an <i>R</i>² value of 0.9987, revealing the excellent regression accuracy for the Vmp. Apart from the accuracy, the system exhibits a low response time and good power tracking under various operating circumstances.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"14 8","pages":"3741-3773"},"PeriodicalIF":3.6,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.70555","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148700030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stability Evaluation and Parametric Optimization of Coal-Concrete Composite Bearing Systems Under Mine-Water-Induced Deterioration: Experiments and FEINN Analysis","authors":"He Wen,&nbsp;Hongchuan Dai,&nbsp;Guixin Zhang,&nbsp;Pengzhe Li,&nbsp;Tong Yang,&nbsp;Cang Gong,&nbsp;Renbo Gao","doi":"10.1002/ese3.70552","DOIUrl":"https://doi.org/10.1002/ese3.70552","url":null,"abstract":"<p>In recent years, the valorization of underground spaces in abandoned coal mines has attracted increasing research attention. Nevertheless, irrespective of the intended application, engineering implementation generally relies on sealed load-bearing units jointly formed by remnant coal pillars and concrete structures to meet the dual requirements of structural stability and long-term sealing performance. Therefore, elucidating the load-bearing and instability mechanisms of concrete-protective coal-pillar composite systems under mine-water exposure, as well as their sensitivity to key parameters, is essential for the safe utilization of underground spaces and the optimization of dam design. This study focuses on the composite dam of the Daliuta Underground Reservoir. A mine-water-simulating saline solution was prepared, and uniaxial and triaxial compression tests were performed on coal rock and concrete under water-induced deterioration to obtain key mechanical parameters and characterize degradation behavior. Building on these results, a coupled FEINN framework integrating physics-informed neural networks and the finite element method was introduced to systematically evaluate the stability responses of different dam configurations and design parameters under extreme hydraulic pressure. Moreover, a unified normalized multi-indicator evaluation scheme was established to enable quantitative ranking and selection among multi-parameter design alternatives. The results provide quantifiable evidence to support the planning, design, operation, and risk mitigation of coal-mine underground reservoirs, and offer theoretical foundations for the green reutilization and long-term safe operation of underground spaces in closed mines.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"14 8","pages":"3697-3725"},"PeriodicalIF":3.6,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.70552","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148700062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and Experimental Study of Pressure Maintenance and Temperature Control System for Hydrate Pressure Core Processing Device","authors":"Liwen Nan,&nbsp;Jiawang Chen,&nbsp;Qiaoling Gao,&nbsp;Yingjie Liu","doi":"10.1002/ese3.70523","DOIUrl":"https://doi.org/10.1002/ese3.70523","url":null,"abstract":"<p>Processing and analyzing hydrate pressure cores in an in situ environment is of great significance for accurately assessing reservoir properties, safeguarding mining safety, and improving the efficiency of resource development. Aiming at the problem of decomposition due to temperature and pressure changes during the processing of hydrate cores, in this paper, a set of pressure maintenance and temperature control systems with active pressure and temperature regulation is designed to maintain the in situ environment of the cores. Through the establishment of a mathematical model of the system and the analysis of time-domain dynamic characteristics, it is found that the pressure maintenance system has good stability and no steady-state error, but there are problems of slow response speed and large overshooting; the temperature control system has fast response and small overshooting, but the steady-state error is large. On the basis of the comparative analysis of proportional–integral–derivative (PID) control strategies, the optimization scheme of using proportional–derivative control for the pressure system and PID control for the temperature system is proposed. The experimental results show that the system can stably control the temperature in the device within the range of 3.0°C–4.5°C and the pressure fluctuation ≤ 3.8% during the core processing, which verifies the feasibility and validity of the designed system, and provides a reliable technical support for the hydrate pressure preservation core processing.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"14 7","pages":"3162-3178"},"PeriodicalIF":3.6,"publicationDate":"2026-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.70523","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148533836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unsteady Flow Behavior and Radial Force Analysis of a Side Channel Pump Under Different Blade Tip Cutting Angles Using Computational Fluid Dynamics","authors":"Kofi Asamoah Adu-Poku,&nbsp;Desmond Appiah,&nbsp;Fan Zhang,&nbsp;Chen Ke","doi":"10.1002/ese3.70542","DOIUrl":"https://doi.org/10.1002/ese3.70542","url":null,"abstract":"<p>Unsteady radial forces in side channel pumps (SCPs) can compromise impeller stability and reduce pump lifespan, yet the impact of blade tip cutting angle (TCA) on these forces remains unclearly characterized. This paper applied Computational Fluid Dynamics (CFD) using the Finite Volume Method (FVM) to investigate the correlation among blade TCAs, internal flow structures and radial force (RF) in SCPs. The following are the two key objectives of the study: first, a quantitative investigation of the flow patterns and RF distribution at varying TCAs (10°, 20°, 30°, 40°, and 50°); second, to understand the underlying processes that result in the observed variation in RFs. The tip of the blade cut exemplifies a noticeable presence in the RF propagations across various operating points in SCP. The RF level is excessive under part-load conditions, constant at design conditions and lower under overload conditions. The mean optimum RF measures 491.2 N; under the flow rate of 0.8 <i>Q</i>_d, 398.6 N; under the flow rate of 1.0 <i>Q</i>_d, and 227.334 N; under the flow rate of 1.2 <i>Q</i>_d, for all TCAs. The maximum RF strength increases proportionally to an increase in the cutting angle between 10° to 30°. Nonetheless, the RF potency decreases at a cutting angle of 40° before peaking at 50°. On the whole, a cutting angle of 10° yields the highest RF magnitude at 106° in part-load conditions, and a cutting angle of 40° yields the lowest RF at 136° in overload conditions, compared to other TCAs. These findings highlight the critical interplay between impeller geometry and radial forces, providing actionable insights for optimizing blade tip design that minimize unsteady forces, reduce vibration, and improve operational stability in pumps.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"14 7","pages":"3458-3471"},"PeriodicalIF":3.6,"publicationDate":"2026-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.70542","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148534320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial Variations in Methane Content and Their Main Controlling Factors of the Deep-Buried Coalbed in the Nalinhe–Hengshan Area, Ordos Basin","authors":"Shi Yunhe,&nbsp;Wang Kangle,&nbsp;Wang Huaichang,&nbsp;Wang Yufei,&nbsp;Zhang Hui,&nbsp;Cao Jingjing,&nbsp;Yin Liangliang,&nbsp;Hu Xinyou,&nbsp;Liang Chao,&nbsp;Liu Mina","doi":"10.1002/ese3.70540","DOIUrl":"https://doi.org/10.1002/ese3.70540","url":null,"abstract":"<p>Deep-buried coalbed methane (DCBM) exhibits significant exploration potential, though with notable spatial variations in gas content. The primary geological factors controlling the differential enrichment of DCBM and their respective influences remain unclear, as their distributions are usually controlled by many factors at the same time. Based on well data and core analysis data, this study focuses on the Coal Seam No. 8 in the Nalinhe–Hengshan areas of the Ordos Basin. Through systematic characterization of coal lithology, quality, reservoir properties, and gas-bearing characteristics, combined with quantitative Pearson correlation analysis, it was determined that ash content is the main factors controlling the spatial variations of the total gas content. The lower ash content, the higher total gas content of the Coal Seam No. 8. It is worth to note that total gas content of the Coal Seam No. 8 in the Nalinhe area (average 11.4 m³/t) is far less than the Hengshan area (average 26.3 m³/t). The Nalinhe area, adjacent to the subaqueous distributary channel mouth bars in the delta front, experienced strong terrigenous clastic input, resulting in a higher proportion of detrital minerals in the coal and consequently higher ash content (average 22.5%). In contrast, the Hengshan area is situated in a lagoon farther from the subaqueous distributary channel mouth bars, with weaker terrigenous input and lower ash content (average 12.8%). Additionally, coal porosity shows a significant positive correlation with free gas content, governing the differences in free gas content between the Nalinhe (average 2.6 m³/t) and the Hengshan (average 10.7 m³/t) areas. The relatively higher ash content in the Nalinhe coal leads to the lower organic maceral content compared to the Hengshan. Well-developed plant cell cavities and fractures in the vitrinite and inertinite contribute to higher porosity in the Hengshan coal. Additionally, the local presence of sandstone in the overlying strata of Coal Seam No. 8 in the Nalinhe area facilitated the escape of free gas into overlying sandstone, further reducing free gas retention. This study improves current knowledge about the enrichment mechanisms of the DCBM.</p>","PeriodicalId":11673,"journal":{"name":"Energy Science & Engineering","volume":"14 7","pages":"3422-3433"},"PeriodicalIF":3.6,"publicationDate":"2026-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ese3.70540","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148534418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}