Gas Science and Engineering最新文献

{"title":"Pore-scale modeling of multiphase reactive transport in porous media during geological carbon storage in saline aquifers: Mechanisms, progress, and challenges","authors":"Jinlei Wang ,&nbsp;Yongfei Yang ,&nbsp;Gloire Imani ,&nbsp;Jie Liu ,&nbsp;Huaisen Song ,&nbsp;Hai Sun ,&nbsp;Lei Zhang ,&nbsp;Junjie Zhong ,&nbsp;Kai Zhang ,&nbsp;Jun Yao","doi":"10.1016/j.jgsce.2025.205784","DOIUrl":"10.1016/j.jgsce.2025.205784","url":null,"abstract":"<div><div>Geological carbon storage (GCS) represents a promising strategy for atmospheric CO₂ reduction and climate change mitigation, with deep saline aquifers standing out as suitable storage sites due to their wide distribution and large storage capacity. The intricate CO₂-brine-rock interactions during GCS in saline aquifers encompass coupled multiphase flow dynamics, multi-component reactive transport, aqueous-phase homogeneous reactions, and fluid/mineral heterogeneous reactions processes. These processes underpin four primary trapping mechanisms: structural trapping, capillary trapping, dissolution trapping, and mineral trapping. Pore-scale modeling bridges the microscopic and macroscopic scales by providing detailed three-dimensional distributions of physical fields within pore spaces while capturing the evolution of porous media due to geochemical reactions. This comprehensive review not only examines the mechanisms and physicochemical processes underlying CO₂ trapping, but also discusses recent advancements in GCS research within saline aquifers from a pore-scale modeling perspective. Furthermore, challenges and future research directions are discussed. This review provides fundamental insights into multiphase reactive transport at pore scale, supporting the development of predictive models that can enhance the safety and efficiency of long-term CO₂ storage in deep saline aquifers.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"145 ","pages":"Article 205784"},"PeriodicalIF":5.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comparative study on the occurrence and pore structure characteristics of CH4 and CO2 hydrates in sandy sediments using SEM-EDS technology","authors":"Lujun Wang ,&nbsp;Haochen Yang ,&nbsp;Chuanqi Sun ,&nbsp;Jianye Sun ,&nbsp;Xiluo Hao ,&nbsp;Chengfeng Li ,&nbsp;Bin Zhu ,&nbsp;Yunmin Chen","doi":"10.1016/j.jgsce.2025.205803","DOIUrl":"10.1016/j.jgsce.2025.205803","url":null,"abstract":"<div><div>CH₄-CO₂ replacement is a novel method that simultaneously enables CH₄ exploitation and CO₂ sequestration. The pore structure of sediments and the microscopic occurrence characteristics of CH₄ and CO₂ hydrates in sediments are key factors that influence the exploitation efficiency and reservoir stability of CH₄ hydrate. In this study, scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS) was employed to conduct microscopic observations and elemental analysis of CH₄ and CO₂ hydrate-bearing sediments. A comparative analysis of their occurrence characteristics and pore structure was performed, and the formation mechanisms of the two hydrates in sediment pores were investigated. The results indicate significant differences in the occurrence patterns of CH₄ and CO₂ hydrates in sediments, which are probably related to the solubility in water of the two gases. CH₄ gas with lower solubility tends to form granular, pore-filling hydrates, while CO₂ gas with higher solubility tends to form flaky or massive cemented and load bearing hydrates. As hydrate saturation increases, the occurrence pattern of CH₄ hydrates shifts from pore-filling to patchy. In contrast, that of CO₂ hydrates transitions from cemented to load bearing and further to patchy. Hydrate saturation significantly affects the pore structure characteristics of sediments. With increasing hydrate saturation, large pores are gradually divided into medium, fine, and micropores, and the pore fractal dimension initially increases and then decreases. The evolution patterns of hydrate occurrence and sediment pore structure characteristics during CH₄-CO₂ replacement are examined in this study, providing valuable insights into efficient hydrate exploitation and reservoir stability analysis.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"145 ","pages":"Article 205803"},"PeriodicalIF":5.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145579304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting in-situ CO2 solubility in formation brines using Raman spectroscopy and machine learning: Implications for offshore geological carbon storage","authors":"Ying Teng ,&nbsp;Yiqi Chen ,&nbsp;Xiran Lin ,&nbsp;Mingkun Bai ,&nbsp;Senyou An ,&nbsp;Shuyang Liu ,&nbsp;Pengfei Wang ,&nbsp;Tao Zhang ,&nbsp;Songbai Han ,&nbsp;Jinlong Zhu ,&nbsp;Jianbo Zhu ,&nbsp;Heping Xie","doi":"10.1016/j.jgsce.2025.205794","DOIUrl":"10.1016/j.jgsce.2025.205794","url":null,"abstract":"<div><div>Accurate estimation of in-situ CO₂ solubility in brine is essential for predicting dissolution trapping efficiency and ensuring the long-term security of geological carbon storage, particularly in deep saline aquifers and offshore reservoirs. Existing experimental and thermodynamic approaches often suffer from limited applicability under high salinity, multi-ion conditions, and diverse reservoir environments, leading to substantial prediction uncertainties. To address this gap, we experimentally determined CO₂ solubility using Raman spectroscopy in both formation brines and synthetic brines under reservoir-relevant conditions (313.15–363.15 K, 7.5–17 MPa) and compiled a comprehensive dataset of 2733 literature entries covering wide salinity and ionic composition ranges. Six machine learning algorithms—LightGBM, XGBoost, CatBoost, SVR, ELM, and KNN—were trained and benchmarked, with LightGBM achieving the highest predictive accuracy. SHAP analysis revealed that pressure, total salinity, and temperature were the dominant factors governing solubility. Model applicability and reliability were confirmed through leverage statistics and Williams plots. Compared with a thermodynamic model, LightGBM delivered superior performance, especially under high-salinity conditions where conventional models often underpredict solubility. The resulting data-driven framework can be readily integrated into reservoir simulation workflows to enable rapid, accurate solubility predictions, optimize injection strategies, and enhance risk assessment for CCS projects in complex geological settings.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"145 ","pages":"Article 205794"},"PeriodicalIF":5.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145269900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cyclic CO2/N2 injection enhances CO2 storage and CH4 recovery in anthracite by optimizing pore structure and competitive adsorption","authors":"Yunzhong Jia ,&nbsp;Jiaqi Yi ,&nbsp;Xinyu Wang ,&nbsp;Zhaolong Ge ,&nbsp;Wenyu Fu ,&nbsp;Yiyu Lu ,&nbsp;Caiyun Xiao","doi":"10.1016/j.jgsce.2025.205779","DOIUrl":"10.1016/j.jgsce.2025.205779","url":null,"abstract":"<div><div>Synergistically optimizing coalbed methane recovery rate and CO₂ sequestration efficiency remains a core bottleneck in CO₂/N₂-ECBM engineering. The competitive adsorption mechanisms underlying the differential impacts of varying CO₂/N₂ ratios on recovery and sequestration are key factors influencing ECBM project performance. Therefore, this study focuses on simulating competitive adsorption mechanisms driven by CO₂/N₂ ratio variations in deep coal reservoir environments to elucidate their critical influence on ECBM efficiency. This study proposes synergistic injection of high-concentration CO₂ from industrial flue gas with associated N₂ into deep coal seams, leveraging N₂-assisted CO₂ delivery through connected pores to improve total storage capacity, thereby realizing cost-effective CO₂ geological storage coupled with coalbed methane stimulation. Through breakthrough adsorption experiments, low-temperature liquid nitrogen adsorption, and nuclear magnetic resonance (NMR) techniques, we investigate the impacts of varying CO₂/N₂ ratios and injection modes (constant pressure/cyclic) on the pore structure and adsorption characteristics of anthracite. Results demonstrate that cyclic injection mode enhances CO₂ adsorption capacity by 28.74 %–40.01 % compared to constant-pressure injection, with a strong positive correlation between micropore volume and adsorption capacity. Although increased N₂ proportion induces pore compression effects, cyclic pressure fluctuations significantly improve macropore porosity (5.67 % increase) and connectivity, facilitating gas diffusion. A three-stage competitive adsorption model is proposed: CO₂ preferentially occupies high-affinity sites, N₂ optimizes transport pathways through pore network expansion, ultimately forming a storage pattern dominated by micropore adsorption and macropore diffusion under dynamic equilibrium. Our results indicate that a 4:1 CO₂/N₂ ratio combined with cyclic injection mode and enhanced meso-macropore porosity synergistically improves both storage efficiency and methane recovery, providing theoretical guidance for gas proportioning and process optimization in CO₂/N₂-ECBM projects.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"145 ","pages":"Article 205779"},"PeriodicalIF":5.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145108868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of leakage characteristics and leakage point diameter prediction in supercritical CO2 pipeline","authors":"Zheyuan Liu ,&nbsp;Jiming He ,&nbsp;Kang Li ,&nbsp;Shi Shen ,&nbsp;Huiyong Liang ,&nbsp;Xin Lv ,&nbsp;Zaixing Liu","doi":"10.1016/j.jgsce.2025.205780","DOIUrl":"10.1016/j.jgsce.2025.205780","url":null,"abstract":"<div><div>This study systematically investigates supercritical CO₂ pipeline leakage dynamics using an integrated experimental platform. Real-time multi-sensor monitoring and high-speed photography reveal continuous phase transitions during leakage, with pressure and temperature exhibiting three distinct stages: stable phase, rapid decline phase, and slow stabilization phase. The Joule-Thomson effect dominates temperature variations, with cooling intensity scaling proportionally to flow velocity. The leakage orifice size significantly influences leakage dynamics: orifices lead to exponentially increasing pressure drops. A relationship between orifice diameter (D) and pressure drop (△P) is established. Jet development is categorized into three stages—slow growth, rapid expansion, and stabilization. Leakage orifice significantly affects jet outlet velocity; at an orifice of 1 mm, velocity changes from 6 m/s to 20 m/s in a short time, and larger orifices exacerbate this change. Variations in leakage orifice diameter exert a more pronounced influence on the jet expansion angle (<em>θ</em>_<em>c</em>). When the orifice diameter increases from 0.5 mm to 3 mm, <em>θ</em>_<em>c</em> rises from 16.365° to 40.965°. In contrast, the core contraction angle (<em>θ</em>_<em>d</em>) demonstrates higher sensitivity to pressure fluctuations: as pressure increases from 8.7 MPa to 9.31 MPa, <em>θ</em>_<em>d</em> increases from 4.844° to 8.615°. These findings provide critical data support for safety design, risk assessment, and emergency response strategies of supercritical CO₂ pipelines.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"145 ","pages":"Article 205780"},"PeriodicalIF":5.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145108869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Capillary trapping in CO2 storage Sites: A traffic light system for preliminary leakage risk assessment","authors":"Mojtaba Ghaedi ,&nbsp;Raoof Gholami ,&nbsp;Spyros Bellas ,&nbsp;Emmanuel Stamatakis","doi":"10.1016/j.jgsce.2025.205807","DOIUrl":"10.1016/j.jgsce.2025.205807","url":null,"abstract":"<div><div>Geological storage of CO₂ offers a promising solution to mitigate global warming. In this context, the structural trapping capacity of subsurface formations is crucial. This study investigates the CO₂ storage capacity of shale caprocks under static conditions by estimating the maximum safe column height of the CO₂ plume beneath them. A modified formulation was developed to incorporate capillary pressure contributions from the reservoir rock. Depth-dependent variations in CO₂–water interfacial tension, wettability, and fluid density were calculated using experimental data and established correlations. Particular attention was given to the effect of total organic content (TOC) on the wettability of caprocks, as some organic-rich source rocks may serve as potential seals for CO₂ storage. Simple and practical equations were proposed to relate wettability to TOC and depth. The results indicate that the capillary pressure of the reservoir rock can often be neglected when estimating CO₂ column height, particularly when the ratio of the reservoir to caprock pore radius exceeds 50. However, neglecting these contributions can lead to overestimations in storage sites when reservoir rock is dense or the caprock is not strongly water-wet. For shale with low TOC (e.g., 0.1 wt%), the optimum storage depth at which the maximum mass of CO₂ can be stored is approximately 1500 m. However, as the TOC of the shale increases, the optimal storage depth and the corresponding mass of CO₂ that can be safely stored decrease significantly. A practical guideline and a traffic light system for preliminary assessment were then proposed to assess the risk of CO₂ capillary leakage. These risks are particularly significant when i) the lowest CO₂ injection point exceeds the safe column height, ii) the gravitational number is less than 0.5, iii) rocks with poor properties hinder horizontal plume propagation beneath the caprock, or iv) CO₂ leakage occurs from underlying formations.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"145 ","pages":"Article 205807"},"PeriodicalIF":5.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145579303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Real-time prediction and inverse design of multiphase CO2 trapping in deep saline aquifers using machine learning enhanced by SHAP analysis","authors":"Shixuan Cheng ,&nbsp;Kai Zhang ,&nbsp;Yihao Li ,&nbsp;Zhangxin Chen","doi":"10.1016/j.jgsce.2025.205782","DOIUrl":"10.1016/j.jgsce.2025.205782","url":null,"abstract":"<div><div>Accurate forecasting of multiphase CO₂ behavior is critical for safe large-scale deployment of carbon capture and storage projects. A total of 9835 high fidelity CMG GEM simulations, covering geological and operational uncertainties in deep saline aquifers, were generated and subsequently used to benchmark thirteen c algorithms for the concurrent prediction of CO₂ trapping mechanisms. Attention based tabular networks TabTransformerLite and SAINTLite together with the decision ensemble NODELite outperformed linear, support vector, tree ensemble, and fully connected neural network baselines. TabTransformerLite secured the best performance with nRMSE of 0.033, R² of 0.92, and minimal fold to fold variability. Shapley value analysis placed depth and permeability as primary controls on dissolved, residual, and mineral precipitated CO₂ compared to the injection rate and porosity. An inverse design workflow used the trained model to identify operating windows that lift mineral trapping above the ninetieth percentile, indicating optimal depth near 2.25 km, permeability above 1.6 Darcy, and injection rates between 7.5 and 14.7 × 10³ m³/day. The resulting framework connects model predictions to geographic information systems for site screening and to real time digital twin optimization, providing a scalable millisecond speed alternative to physics-based simulation for CO₂ storage planning and monitoring.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"145 ","pages":"Article 205782"},"PeriodicalIF":5.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145108864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of dynamic production characteristics and identification of segmentation nodes in decline models for deep coalbed methane using physics-informed neural networks","authors":"Danqun Wang ,&nbsp;Jingtao Lai ,&nbsp;Tiantian Zhang ,&nbsp;Zhiping Li ,&nbsp;Jianping Guo","doi":"10.1016/j.jgsce.2025.205786","DOIUrl":"10.1016/j.jgsce.2025.205786","url":null,"abstract":"<div><div>Deep coalbed methane (CBM) offers clean, sustainable energy, but its low-carbon potential and resource value require enhanced production. Conventional data-driven models lack physical interpretability and often miss key reservoir dynamics. This study presents a physics-informed neural network (PINN) long short-term memory (LSTM) model that embeds decline-curve analysis (DCA) and the Langmuir adsorption–desorption equation as physical constraints. Production time-series from six Ordos Basin wells were used for training and validation. Hyperbolic, stretched-exponential production decline (SEPD), Duong, and Langmuir constraints were systematically evaluated and linked to production–extraction mechanisms. A time-varying coupling strategy divides the production cycle into segments, applying the optimal decline model in each stage. Compared to a standard LSTM, the PINN-LSTM delivers higher accuracy, robustness, and interpretability. Early-stage fluctuating wells gain from Langmuir regularization, while mid-to-late-life wells see improved precision under hyperbolic and Duong constraints. The coupling strategy reduces prediction error by 10 % and raises R² by 0.11. Temporal segmentation pinpoints transition nodes and captures operational fluctuations. These results guide intelligent CBM production control and future model enhancements.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"145 ","pages":"Article 205786"},"PeriodicalIF":5.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145333695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of cracks caused by hydrogen damage in HSLA X70 in sour gas media using conventional and non-destructive techniques","authors":"Janeth M. Quispe-Avilés ,&nbsp;Roger Imata-Condori ,&nbsp;Gonzalo Aurelio Mamani-Quiñones ,&nbsp;Hugo Canahua-Loza ,&nbsp;Elvis G. Gonzales-Condori ,&nbsp;Edwan Anderson Ariza-Echeverri","doi":"10.1016/j.jgsce.2025.205778","DOIUrl":"10.1016/j.jgsce.2025.205778","url":null,"abstract":"<div><div>High-strength low-alloy (HSLA) steels are widely used in the oil industry for manufacturing durable and efficient pipelines due to their exceptional mechanical properties, including high strength, toughness, ductility, and weldability. However, their long-term reliability in sour gas environments remains a critical concern, particularly due to their susceptibility to hydrogen-induced cracking (HIC), which can compromise pipeline integrity and lead to catastrophic failures. While advanced crack detection methods provide high-resolution analysis, they are costly, time-consuming, and require specialized equipment, limiting their application in large-scale pipeline monitoring and failure prevention. This study explores liquid penetrant inspection as a low-cost, non-destructive alternative for detecting HIC in HSLA X70 steel exposed to sour gas conditions (NACE TM0284). By integrating both conventional techniques (optical microscopy, scanning electron microscopy, electrochemical testing, and Brinell hardness measurements) and non-destructive methods, this research provides a comprehensive evaluation of crack initiation, propagation, and detection strategies. The findings demonstrate that corrosion was most severe under H₂S-saturated conditions; however, oxygenated environments also induced a significant corrosion rate of a similar order of magnitude, underscoring its underestimated role in accelerating hydrogen damage. Furthermore, liquid penetrant inspection proved effective as a rapid, cost-efficient, and industrially viable technique for crack detection, offering a scalable solution for failure analysis and preventive maintenance in the oil and gas sector.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"145 ","pages":"Article 205778"},"PeriodicalIF":5.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145424808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of discontinuous fluid interfaces on pressure drops and relative permeabilities for gas-liquid two-phase flow in porous media","authors":"Jiafan Guo ,&nbsp;Zhechao Wang ,&nbsp;Liping Qiao ,&nbsp;Hao Feng ,&nbsp;Wei Li","doi":"10.1016/j.jgsce.2025.205795","DOIUrl":"10.1016/j.jgsce.2025.205795","url":null,"abstract":"<div><div>After gas is injected into the Earth's crust, it gradually transitions from continuous flow to discontinuous flow as the flow distance increases. This study aims to investigate the relationship between pressure drop and fluid interface properties in gas-liquid two-phase discontinuous flow. Based on the capillary bundle model, a simple equation is proposed to separate the capillary pressure drop caused by the fluid interfaces from the viscous pressure drop within the total pressure drop of gas-liquid two-phase flow. The viscous pressure drop is linearly related to both the flow rate and the effective viscosity of the gas and liquid, while the capillary pressure drop is indirectly derived from the viscous pressure drop. Through steady-state gas-liquid two-phase flow experiments in micromodels, we further determined that the capillary pressure drop is linearly related to the specific interfacial area of the moving fluid. Moreover, the slope of this linear relationship decreases as the flow rate increases, showing a negative exponential power function relationship. By regression analysis, we established the functional relationship between the specific interfacial area and variables such as gas volume fraction, flow rate, viscosity, and pore structure. Based on this, we empirically derived a calculation formula for two-phase relative permeability as a function of the specific interfacial area. This study quantifies the significant influence of fluid interface on both pressure drop and relative permeability in discontinuous flow.</div></div>","PeriodicalId":100568,"journal":{"name":"Gas Science and Engineering","volume":"145 ","pages":"Article 205795"},"PeriodicalIF":5.5,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145424809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}