期刊文献+
共找到59篇文章
< 1 2 3 >
每页显示 20 50 100
Integrated numerical simulation of hydraulic fracturing and production in shale gas well considering gas-water two-phase flow
1
作者 TANG Huiying LUO Shangui +4 位作者 LIANG Haipeng ZENG Bo ZHANG Liehui ZHAO Yulong SONG Yi 《Petroleum Exploration and Development》 SCIE 2024年第3期684-696,共13页
Based on the displacement discontinuity method and the discrete fracture unified pipe network model,a sequential iterative numerical method was used to build a fracturing-production integrated numerical model of shale... Based on the displacement discontinuity method and the discrete fracture unified pipe network model,a sequential iterative numerical method was used to build a fracturing-production integrated numerical model of shale gas well considering the two-phase flow of gas and water.The model accounts for the influence of natural fractures and matrix properties on the fracturing process and directly applies post-fracturing formation pressure and water saturation distribution to subsequent well shut-in and production simulation,allowing for a more accurate fracturing-production integrated simulation.The results show that the reservoir physical properties have great impacts on fracture propagation,and the reasonable prediction of formation pressure and reservoir fluid distribution after the fracturing is critical to accurately predict the gas and fluid production of the shale gas wells.Compared with the conventional method,the proposed model can more accurately simulate the water and gas production by considering the impact of fracturing on both matrix pressure and water saturation.The established model is applied to the integrated fracturing-production simulation of practical horizontal shale gas wells.The simulation results are in good agreement with the practical production data,thus verifying the accuracy of the model. 展开更多
关键词 shale gas well hydraulic fracturing fracture propagation gas-water two-phase flow fracturing-production integrated numerical simulation
下载PDF
Optimizing Two-Phase Flow Heat Transfer:DCS Hybrid Modeling and Automation in Coal-Fired Power Plant Boilers
2
作者 Ming Yan Caijiang Lu +3 位作者 Pan Shi Meiling Zhang Jiawei Zhang Liang Wang 《Frontiers in Heat and Mass Transfer》 EI 2024年第2期615-631,共17页
In response to escalating challenges in energy conservation and emission reduction,this study delves into the complexities of heat transfer in two-phase flows and adjustments to combustion processes within coal-fired ... In response to escalating challenges in energy conservation and emission reduction,this study delves into the complexities of heat transfer in two-phase flows and adjustments to combustion processes within coal-fired boilers.Utilizing a fusion of hybrid modeling and automation technologies,we develop soft measurement models for key combustion parameters,such as the net calorific value of coal,flue gas oxygen content,and fly ash carbon content,within theDistributedControl System(DCS).Validated with performance test data,thesemodels exhibit controlled root mean square error(RMSE)and maximum absolute error(MAXE)values,both within the range of 0.203.Integrated into their respective automatic control systems,thesemodels optimize two-phase flow heat transfer,finetune combustion conditions,and mitigate incomplete combustion.Furthermore,this paper conducts an in-depth exploration of the generationmechanismof nitrogen oxides(NOx)and low oxygen emission reduction technology in coal-fired boilers,demonstrating a substantial reduction in furnace exit NOx generation by 30%to 40%and the power supply coal consumption decreased by 1.62 g/(kW h).The research outcomes highlight the model’s rapid responsiveness,enabling prompt reflection of transient variations in various economic indicator parameters.This provides a more effective means for real-time monitoring of crucial variables in coal-fired boilers and facilitates timely combustion adjustments,underscoring notable achievements in boiler combustion.The research not only provides valuable and practical insights into the intricacies of two-phase flow heat transfer and heat exchange but also establishes a pioneering methodology for tackling industry challenges. 展开更多
关键词 two-phase flow coal-fired boiler oxygen content of flue gas carbon content in fly ash hybrid modeling automation control
下载PDF
Simulation of Gas-Water Two-Phase Flow in Tight Gas Reservoirs Considering the Gas Slip Effect
3
作者 Mingjing Lu Zenglin Wang +3 位作者 Aishan Li Liaoyuan Zhang Bintao Zheng Zilin Zhang 《Fluid Dynamics & Materials Processing》 EI 2023年第5期1269-1281,共13页
A mathematical model for the gas-water two-phase flow in tight gas reservoirs is elaborated.The model can account for the gas slip effect,stress sensitivity,and high-speed non-Darcy factors.The related equations are s... A mathematical model for the gas-water two-phase flow in tight gas reservoirs is elaborated.The model can account for the gas slip effect,stress sensitivity,and high-speed non-Darcy factors.The related equations are solved in the framework of a finite element method.The results are validated against those obtained by using the commercial software CMG(Computer Modeling Group software for advanced recovery process simulation).It is shown that the proposed method is reliable.It can capture the fracture rejection characteristics of tight gas reservoirs better than the CMG.A sensitivity analysis of various control factors(initial water saturation,reservoir parameters,and fracturing parameters)affecting the production in tight gas wells is conducted accordingly.Finally,a series of theoretical arguments are provided for a rational and effective development/exploitation of tight sandstone gas reservoirs. 展开更多
关键词 Tight gas reservoir gas-water two-phase flow numerical simulation fractured horizontal well gas slip effect
下载PDF
Numerical Simulation of Liquified Natural Gas Boiling Heat Transfer Characteristics in Helically Coiled Tube-in-Tube Heat Exchangers
4
作者 Fayi Yan He Lu Shijie Feng 《Frontiers in Heat and Mass Transfer》 EI 2024年第5期1493-1514,共22页
Helically coiled tube-in-tube(HCTT)heat exchangers are widely applied to the process technology because of their compactness and higher heat transfer efficiency.HCTT heat exchangers play an important role in liquified... Helically coiled tube-in-tube(HCTT)heat exchangers are widely applied to the process technology because of their compactness and higher heat transfer efficiency.HCTT heat exchangers play an important role in liquified natural gas(LNG)use and cold energy recovery.The heat transfer characteristics,pressure distribution,and degree of vaporization of LNG in HCTT heat exchangers are numerically investigated.By comparing the simulation results of the computational model with existing experimental results,the effectiveness of the computational model is verified.The numerical simulation results show the vapor volume fraction of the HCTT heat exchanger is related to the inlet Reynolds number,inner tube diameters,and helix diameter.The vapor volume fraction increases rapidly from the fourth to the seventh equal division points of the helix tube length.On condition that the inlet Reynolds number is greater than 33500,the pressure drop rate gradually increases.When the magnitude of the vapor volume fraction is below 0.2,the heat transfer coefficient increase rate is greater than that when the vapor volume fraction is above 0.2.The heat exchange efficiency of HCTT heat exchangers increases with the decrease of the ratio of helix diameter to inner tube diameter. 展开更多
关键词 Liquefied natural gas numerical simulation vapor-liquid two-phase flow heat transfer helically coiled tube-intube heat exchanger
下载PDF
Quantitative research of the liquid film characteristics in upward vertical gas, oil and water flows
5
作者 Dayang Wang Ningde Jin +1 位作者 Lusheng Zhai Yingyu Ren 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期67-79,共13页
The study of liquid film characteristics in multiphase flow is a very important research topic, however,the characteristics of the liquid film around Taylor bubble structure in gas, oil and water three-phase flow are ... The study of liquid film characteristics in multiphase flow is a very important research topic, however,the characteristics of the liquid film around Taylor bubble structure in gas, oil and water three-phase flow are not clear. In the present study, a novel liquid film sensor is applied to measure the distributed signals of the liquid film in three-phase flow. Based on the liquid film signals, the liquid film characteristics including the structural characteristics and the nonlinear dynamics characteristics in three-phase flows are investigated for the first time. The structural characteristics including the proportion, the appearance frequency and the thickness of the liquid film are obtained and the influences of the liquid and gas superficial velocities and the oil content on them are investigated. To investigate the nonlinear dynamics characteristics of the liquid film with the changing flow conditions, the entropy analysis is introduced to successfully uncover and quantify the dynamic complexity of the liquid film behavior. 展开更多
关键词 gas oil and water three-phase flow Liquid film characteristics Liquid film sensor Nonlinear dynamics analysis
下载PDF
Liquid holdup measurement with double helix capacitance sensor in horizontal oil-water two-phase flow pipes 被引量:5
6
作者 翟路生 金宁德 +1 位作者 高忠科 王振亚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期268-275,共8页
This paper presents the characteristics of a double helix capacitance sensor for measurement of the liquid holdup in horizontal oil–water two-phase flow. The finite element method is used to calculate the sensitivity... This paper presents the characteristics of a double helix capacitance sensor for measurement of the liquid holdup in horizontal oil–water two-phase flow. The finite element method is used to calculate the sensitivity field of the sensor in a pipe with 20 mm inner diameter and the effect of sensor geometry on the distribution of sensitivity field is presented. Then, a horizontal oil–water two-phase flow experiment is carried out to measure the response of the double helix capacitance sensor, in which a novel method is proposed to calibrate the liquid holdup based on three pairs of parallel-wire capacitance probes. The performance of the sensor is analyzed in terms of the flow structures detected by mini-conductance array probes. 展开更多
关键词 Horizontal oil–water two-phase flow Liquid holdup measurement Double helix capacitance sensor flow pattern
下载PDF
An analytical model for water-oil two-phase flow in inorganic nanopores in shale oil reservoirs 被引量:4
7
作者 Ran Li Zhangxin Chen +2 位作者 Keliu Wu Xing Hao Jinze Xu 《Petroleum Science》 SCIE CAS CSCD 2021年第6期1776-1787,共12页
The existence of water phase occupies oil flow area and impacts the confined oil flow behavior at the solid substrate in inorganic nanopores of shale oil reservoirs,resulting in a completely different flow pattern whe... The existence of water phase occupies oil flow area and impacts the confined oil flow behavior at the solid substrate in inorganic nanopores of shale oil reservoirs,resulting in a completely different flow pattern when compared with the single oil phase flow.This study proposes an analytical model to describe the water-oil two-phase flow.In this model,water slippage at the solid substrate is considered while oil slip is introduced to calculate the oil movement at the solid-oil boundary in dry conditions.It is proven that the oil flow profiles of both the two-phase model and single-phase model show parabolic shapes,but the oil flow capacity drops when water takes up the flow space and the impact of water is more significant when the pore dimension is smaller than 30 nm.Also,the oil flow velocity at a pore center is found to drop linearly given a larger water saturation in wet conditions.The effects of surface wettability and oil properties on water-oil flow are also discussed.Compared with the existing singlephase models,this model describes oil flow pattern in the wet condition with the incorporation of the influence of nanopore properties,which better predicts the oil transport in actual reservoir conditions.Water-oil relative permeability curves are also obtained to improve oil yield. 展开更多
关键词 Shale oil Water films two-phase flow NANOPORE
下载PDF
Parametric study of gas−liquid two-phase flow field in horizontal stirred tank 被引量:8
8
作者 Zhi-bin CHEN Hong-jie YAN +4 位作者 Ping ZHOU Ping YANG Jie-hui DING Jia LIU Liu LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第6期1806-1817,共12页
Based on Fluent software,the gas−liquid two-phase flow in the horizontal stirred tank was simulated with SST k−ωturbulence model,Eulerian−Eulerian two-fluid model,and multi-reference flame method.The mixing process i... Based on Fluent software,the gas−liquid two-phase flow in the horizontal stirred tank was simulated with SST k−ωturbulence model,Eulerian−Eulerian two-fluid model,and multi-reference flame method.The mixing process in the tank was calculated by tracer method.The results show that increasing the rotating speed or gas flow is conducive to a more uniform distribution of the gas phase and accelerates the mixing of the liquid phase.When the rotating speed exceeds 93 r/min,the relative power demand remains basically constant.The change in the inclination angle of the upper impeller has minimal effect on the gas phase distribution.When the inclination angle is 50°,the relative power demand reaches the maximum.An appropriate increase in the impeller distance from the bottom improves the gas holdup and gas phase distribution but increases the liquid phase mixing time. 展开更多
关键词 horizontal stirred tank gas−liquid two-phase flow Eulerian−Eulerian two-fluid model multiple reference frame method
下载PDF
NUMERICAL MODELING OF TURBULENTEVAPORATING GAS-DROPLET TWO-PHASE FLOWS IN AN AFTERBURNER DIFFUSOR OF TURBO-FAN JET ENGINES
9
作者 Zhou Lixing and Zhang JianTsinghua University 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1990年第4期258-265,共8页
The two-dimensional turbulent evaporating gas-droplet two-phase flows in an afterburner diffusor of turbo-fan jet engines are simulated by the k-ε turbulence model and the particle trajectory model. Comparison of pre... The two-dimensional turbulent evaporating gas-droplet two-phase flows in an afterburner diffusor of turbo-fan jet engines are simulated by the k-ε turbulence model and the particle trajectory model. Comparison of predicted gas velocity and temperature distributions with experimental results for the cases without liquid spray shows pretty good agreement. Gas-droplet two-phase flow predictions give plausible droplet trajectories, fuel-vapor concentration distribution, gas-phase velocity and temperature field in presence of liquid droplets. One run of computation with this method is made for a particular afterburner. The results indicate that the location of the atomizers is not favorable to flame stabilization and combustion efficiency. The proposed numerical modeling can also be adopted for optimization design and performance evaluation of afterburner combustors of turbo-fan jet engines. 展开更多
关键词 NUMERICAL MODELING OF TURBULENTEVAPORATING gas-DROPLET two-phase flowS IN AN AFTERBURNER DIFFUSOR OF TURBO-FAN JET ENGINES JET gas
下载PDF
SIMULATION OF GAS AND LIQUID TWO-PHASE FLOW THROUGH THE BLAST FURNACE DROPPING ZONE
10
作者 谢裕生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS 1985年第1期63-76,共14页
A three-dimensional mathematical model,based on differential balances of mass and momentum,hasbeen developed to describe the two-phase flow of gas and liquid through the dropping zone of the blast fur-nace.Agreement b... A three-dimensional mathematical model,based on differential balances of mass and momentum,hasbeen developed to describe the two-phase flow of gas and liquid through the dropping zone of the blast fur-nace.Agreement between observed and calculated values verifies the validity of this model.On the basis of this model,various parameters for the surrounding of the dry zone of Blast FurnaceNo.I-BF of the Beijing Iron and Steel Company have been computed,from which a diagram for demar-cation of fluidization of coke and flooding of slag has been proposed. 展开更多
关键词 SIMULATION OF gas AND LIQUID two-phase flow THROUGH THE BLAST FURNACE DROPPING ZONE
下载PDF
Shale oil and gas exploitation in China:Technical comparison with US and development suggestions 被引量:3
11
作者 LEI Qun WENG Dingwei +5 位作者 GUAN Baoshan SHI Junfeng CAI Bo HE Chunming SUN Qiang HUANG Rui 《Petroleum Exploration and Development》 SCIE 2023年第4期944-954,共11页
The shale oil and gas exploitation in China is technically benchmarked with the United States in terms of development philosophy,reservoir stimulation treatment,fracturing parameters,fracturing equipment and materials... The shale oil and gas exploitation in China is technically benchmarked with the United States in terms of development philosophy,reservoir stimulation treatment,fracturing parameters,fracturing equipment and materials,oil/gas production technology,and data/achievements sharing.It is recognized that the shale oil and gas exploitation in China is weak in seven aspects:understanding of flow regimes,producing of oil/gas reserves,monitoring of complex fractures,repeated stimulation technology,oil/gas production technology,casing deformation prevention technology,and wellbore maintenance technology.Combined with the geological and engineering factors of shale oil and gas in China,the development suggestions of four projects are proposed from the macro-and micro-perspective,namely,basic innovation project,exploitation technology project,oil/gas production stabilization project,and supporting efficiency-improvement project,so as to promote the rapid,efficient,stable,green and extensive development of shale oil and gas industry chain and innovation chain and ultimately achieve the goal of“oil volume stabilizing and gas volume increasing”. 展开更多
关键词 shale oil and gas reservoir stimulation oil/gas production technology oil/gas development philosophy reservoir stimulation treatment flow regime
下载PDF
Inter-layer interference for multi-layered tight gas reservoir in the absence and presence of movable water 被引量:2
12
作者 Tao Zhang Bin-Rui Wang +5 位作者 Yu-Long Zhao Lie-Hui Zhang Xiang-Yang Qiao Lei Zhang Jing-Jing Guo Hung Vo Thanh 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1751-1764,共14页
Due to the dissimilarity among different producing layers,the influences of inter-layer interference on the production performance of a multi-layer gas reservoir are possible.However,systematic studies of inter-layer ... Due to the dissimilarity among different producing layers,the influences of inter-layer interference on the production performance of a multi-layer gas reservoir are possible.However,systematic studies of inter-layer interference for tight gas reservoirs are really limited,especially for those reservoirs in the presence of water.In this work,five types of possible inter-layer interferences,including both absence and presence of water,are identified for commingled production of tight gas reservoirs.Subsequently,a series of reservoir-scale and pore-scale numerical simulations are conducted to quantify the degree of influence of each type of interference.Consistent field evidence from the Yan'an tight gas reservoir(Ordos Basin,China)is found to support the simulation results.Additionally,suggestions are proposed to mitigate the potential inter-layer interferences.The results indicate that,in the absence of water,commingled production is favorable in two situations:when there is a difference in physical properties and when there is a difference in the pressure system of each layer.For reservoirs with a multi-pressure system,the backflow phenomenon,which significantly influences the production performance,only occurs under extreme conditions(such as very low production rates or well shut-in periods).When water is introduced into the multi-layer system,inter-layer interference becomes nearly inevitable.Perforating both the gas-rich layer and water-rich layer for commingled production is not desirable,as it can trigger water invasion from the water-rich layer into the gas-rich layer.The gas-rich layer might also be interfered with by water from the neighboring unperforated water-rich layer,where the water might break the barrier(eg weak joint surface,cement in fractures)between the two layers and migrate into the gas-rich layer.Additionally,the gas-rich layer could possibly be interfered with by water that accumulates at the bottom of the wellbore due to gravitational differentiation during shut-in operations. 展开更多
关键词 Tight gas Comingled production INTERFERENCE two-phase flow Water blocking
下载PDF
Features of Sandy Debris Flows of the Yanchang Formation in the Ordos Basin and Its Oil and Gas Exploration Significance 被引量:26
13
作者 LI Xiangbo CHEN Qilin +4 位作者 LIU Huaqing WAN Yanrong WEI Lihua LIAO Jianbo LONG Liwen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第5期1187-1202,共16页
Sandy debris flow is a new genetic type of sand bodies,which has gained much attention in recent years and its corresponding theory is proved to be a significant improvement and even partial denial to the 'Bouma S... Sandy debris flow is a new genetic type of sand bodies,which has gained much attention in recent years and its corresponding theory is proved to be a significant improvement and even partial denial to the 'Bouma Sequence' and 'turbidite fan' deep-water sedimentary theories to some point. Oil exploration researchers are highly concerned with sandy debris flows for its key role in controlling oil and gas accumulation processes.In this article,by applying sandy debris flows theory and combining a lot work of core,outcrop observation and analysis plus seismic profile interpretation,we recognized three types of sedimentary gravity flows that are sandy debris flows,classic turbidites and slumping rocks in chang-6 member of Yanchang Formation in the deep-water area of central Ordos Basin.Among the three types,the sandy debris flows are the most prominent and possesses the best oil bearing conditions.On the contrary,the classic turbidites formed by turbidity currents are limited in distribution;therefore,previous Yanchang Formation deep-water sedimentary studies have exaggerated the importance of turbidite currents deposition.Further study showed that the area distribution of deep water gravity flow sand bodies in Yanchang Formation were controlled by the slope of the deep-water deposits and the flows had vast distribution,huge depth and prevalent advantages for oil forming,which make it one of the most favorable new areas for Ordos Basin prospecting. 展开更多
关键词 sandy debris flows sedimentary characteristics oil and gas prospecting values Yanchang Formation Ordos Basin
下载PDF
Prediction of Flowing Bottomhole Pressures for Two-Phase Coalbed Methane Wells 被引量:5
14
作者 LIU Xinfu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第5期1412-1420,共9页
A method is proposed to predict the flowing bottomhole pressures (FBHPs) for two-phase coalbed methane (CBM) wells. The mathematical models for both gas column pressure and two-phase fluid column pressure were dev... A method is proposed to predict the flowing bottomhole pressures (FBHPs) for two-phase coalbed methane (CBM) wells. The mathematical models for both gas column pressure and two-phase fluid column pressure were developed based on the well liquid flow equation. FBHPs during the production were predicted by considering the effect of entrained liquid on gravitational gradients. Comparison of calculated BHPs by Cullender-Smith and proposed method was also studied. The results show that the proposed algorithm gives the desired accuracy of calculating BHPs in the low- productivity and low-pressure CBM wells. FBHP is resulted from the combined action of wellhead pressure, gas column pressure and fluid column pressure. Variation of kinetic energy term, compressibility and friction factors with depth increments and liquid holdup with velocity should be considered to simulate the real BHPs adequately. BHP is a function of depth of each column segment. The small errors of less than 1.5% between the calculated and measured values are obtained with each segment within 25 m. Adjusting BHPs can effectively increase production pressure drop, which is beneficial to CBM desorption and enhances reservoir productivity. The increment of pressure drop from 5.37 MPa2 to 8.66 MPa2 leads to an increase of CBM production from 3270 m3/d to 6700 m3/d and is attributed to a decrease in BHP from 2.25 MPa to 1.33 MPa. 展开更多
关键词 coalbed methane productivity flowing bottomhole pressure gas column pressure two-phase fluid column pressure
下载PDF
Simulation Experiments in Electromagnetic Tomography Well Logging in Two-phase Flow 被引量:2
15
作者 Wu Xiling Zhao Yanwei 《Petroleum Science》 SCIE CAS CSCD 2006年第3期41-44,共4页
Electromagnetic Computer Tomography (ECT) is a method to probe the interior of an inhomogeneous medium via surface measurement in a non-linear way. Due to the great differences in conductivity and permittivity betwe... Electromagnetic Computer Tomography (ECT) is a method to probe the interior of an inhomogeneous medium via surface measurement in a non-linear way. Due to the great differences in conductivity and permittivity between oil and water in the well, Electromagnetic Tomography Well Logging (ETWL), a new flow imaging measurement system, is proposed to describe the distribution and movement of oil/water two-phase flow in the well by scanning the detected region and applying a suitable data processing algorithm. The results of the numerical simulation and physical modeling show that the system could provide a clear image of the flow profile. 展开更多
关键词 oil well two-phase flow electromagnetic tomography well logging
下载PDF
Deep-water gravity flow deposits in a lacustrine rift basin and their oil and gas geological significance in eastern China 被引量:5
16
作者 CAO Yingchang JIN Jiehua +5 位作者 LIU Haining YANG Tian LIU Keyu WANG Yanzhong WANG Jian LIANG Chao 《Petroleum Exploration and Development》 CSCD 2021年第2期286-298,共13页
The types,evolution processes,formation mechanisms,and depositional models of deep-water gravity flow deposits in a lacustrine rift basin are studied through core observation and systematic analysis.Massive transport ... The types,evolution processes,formation mechanisms,and depositional models of deep-water gravity flow deposits in a lacustrine rift basin are studied through core observation and systematic analysis.Massive transport of slide and slump,fluid transport of debris flow and turbidity currents are driven by gravity in deep-water lacustrine environment.The transformation between debris flow and turbidity current,and the transformation of turbidity current between supercritical and subcritical conditions are the main dynamic mechanisms of gravity flow deposits in a lake basin.The erosion of supercritical turbidity current controls the formation of gravity-flow channel.Debris flow deposition gives rise to tongue shape lobe rather than channel.Deep-water gravity flow deposits are of two origins,intrabasinal and extrabasinal.Intrabasinal gravity flow deposits occur as single tongue-shape lobe or fan of stacking multiple lobes.Extrabasinal gravity-flow deposits occur as sublacustrine fan with channel or single channel sand body.However,the nearshore subaqueous fan is characterized by fan of stacking multiple tongue shape lobes without channel.The differential diagenesis caused by differentiation in the nearshore subaqueous fan facies belt results in the formation of diagenetic trap.The extrabasinal gravity flow deposits are one of the important reasons for the abundant deep-water sand bodies in a lake basin.Slide mass-transport deposits form a very important type of lithologic trap near the delta front often ignored.The fine-grained sediment caused by flow transformation is the potential"sweet spot"of shale oil and gas. 展开更多
关键词 turbidity current debris flow deep-water gravity-flow deposits depositional model oil and gas geological significance fault lake basin
下载PDF
Near-source characteristics of two-phase gas-solid outbursts in roadways 被引量:1
17
作者 Aitao Zhou Meng Zhang +1 位作者 Kai Wang Derek Elsworth 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第4期685-696,共12页
Coal and gas outbursts compromise two-phase gas-solid mixtures as they propagate as shock waves and flows from their sources.Propagation is influenced by the form of the outburst,proximity to source,the structure and ... Coal and gas outbursts compromise two-phase gas-solid mixtures as they propagate as shock waves and flows from their sources.Propagation is influenced by the form of the outburst,proximity to source,the structure and form of the transmitting roadways and the influence of obstacles.The following characterizes the propagation of coal and gas outbursts as two-phase gas-solid flows proximal to source where the coupled effects of pulverized coal and gas flows dominate behavior.The characteristics of shock wave propagation and attenuation were systematically examined for varied roadway geometries using experiments and numerical models.The results demonstrate that the geometry of roadway obstructions is significant and may result in partial compression and sometimes secondary overpressurization in blocked and small comer roadways leading to significant attenuation of outburst shock waves.The shock waves attenuate slowly in both straight and abruptly expanding roadways and more significantly in T-shaped roadways.The most significant attenuation appears in small angle comers and bifurcations in roadways with the largest attenuation occurring in blocked roadways.These results provide basic parameters for simplifying transport in complex roadway networks in the far-field,and guidance for the design of coal and gas outburst prevention facilities and emergency rescue. 展开更多
关键词 Coal and gas outburst Proximity to source Shock wave propagation two-phase gas-solid flow Outburst prevention
下载PDF
Depositional process of hyperpycnal flow deposits:A case study on Lower Cretaceous Sangyuan outcrop in the Luanping Basin,Northeast China
18
作者 De-zhi Yan Ru-kai Zhu +8 位作者 Hao Shou Zhao-hui Xu Wei-hong Liu Si-cheng Zhu Zhi-cheng Lei Jing-ya Zhang Chang Liu Yi Cai Huai-min Xu 《China Geology》 CAS CSCD 2024年第3期505-516,共12页
Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this... Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and deceleration.In the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up gradually.Deposits developed in the acceleration phase are reverse.In addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force.As a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin.In the erosion phase,the reverse deposits are eroded and become thinner or even disappear.Therefore,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the source.After entering the deceleration phase,normally grading deposits appear and cover previous deposits.The final deposits in the basin are special.Some are reverse,and others are normal.They are superimposed with each other under the action of hyperpycnal flow.The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of hyperpycnites.It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits. 展开更多
关键词 Hyperpycnal flow Sedimentary characteristics Depositional process Gravity flow deposit Hyperpycnite Red mud pebble Gray mud pebble oil and gas exploration engineering Luanping Basin
下载PDF
Multi-scale complexity entropy causality plane: An intrinsic measure for indicating two-phase flow structures
19
作者 窦富祥 金宁德 +2 位作者 樊春玲 高忠科 孙斌 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期85-96,共12页
We extend the complexity entropy causality plane(CECP) to propose a multi-scale complexity entropy causality plane(MS-CECP) and further use the proposed method to discriminate the deterministic characteristics of ... We extend the complexity entropy causality plane(CECP) to propose a multi-scale complexity entropy causality plane(MS-CECP) and further use the proposed method to discriminate the deterministic characteristics of different oil-in-water flows. We first take several typical time series for example to investigate the characteristic of the MS-CECP and find that the MS-CECP not only describes the continuous loss of dynamical structure with the increase of scale, but also reflects the determinacy of the system. Then we calculate the MS-CECP for the conductance fluctuating signals measured from oil–water two-phase flow loop test facility. The results indicate that the MS-CECP could be an intrinsic measure for indicating oil-in-water two-phase flow structures. 展开更多
关键词 oil–water two-phase flow fluid dynamics complexity entropy MULTI-SCALE
下载PDF
Gas Condensate Two Phase Flow Performance in Porous Media Considering Capillary Number and Non-Darcy Effects
20
作者 覃斌 李相方 程时清 《Petroleum Science》 SCIE CAS CSCD 2004年第3期49-55,共7页
Retrograde condensation frequently occurs during the development of gas condensate reservoirs. The loss of productivity is often observed due to the reduced relative permeability to gas as condensate accumulates ne... Retrograde condensation frequently occurs during the development of gas condensate reservoirs. The loss of productivity is often observed due to the reduced relative permeability to gas as condensate accumulates near the well bore region. How to describe the condensate blockage effect exactly has been a continuous research topic. However, up to now, the present methods usually over-estimate or underestimate the productivity reduction due to an incorrect understanding of the mechanism of flow in porous medium, which inevitably results in an inaccurate prediction of production performance. It has been found in recent numerous theoretical and experimental studies that capillary number and non-Darcy flow have significant influence on relative permeability in regions near the well bore. The two effects impose opposite impacts on production performance, thus leading to gas condensate flow showing characteristics different from general understanding. It is significant for prediction of performance in gas condensate wells to understand the two effects exactly. The aim of the paper is to describe and analyze the flow dynamics in porous media accurately during the production of gas condensate reservoirs. Based on the description of three-zone flow mechanism, capillary number and non-Darcy effect are incorporated in the analysis of relative permeability, making it possible to describe the effect of condensate blockage. The effect of capillary number and inertial flow on gas and condensate relative permeability is analyzed in detail. Novel Inflow Performance Relation (IPR) models considering high velocity effects are formulated and the contrast analysis of different IPR models is conducted. The result shows that the proposed method can help predict the production performance and productivity more accurately than conventional methods. 展开更多
关键词 gas condensate two-phase flow porous media capillary number non-Darcy effect
下载PDF
上一页 1 2 3 下一页 到第
使用帮助 返回顶部