检索结果-南通市图书馆

Syntheses and properties of associative acrylamide copolymers containing short hydrophobic chains used in a friction reducer for slick-water fracturing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum science 2024年第3期21卷 1889-1901页

作者： Ya-Xing Dai Xian-Li Zhang Si-Yuan Liu Feng-Run-Ze Zhang Yi-Xi Zhang Yu-Tong Sang Jing-Xi Zheng Zhao-Sheng Liu Peng Zhang College of Chemistry and Chemical Engineering Chongqing University of Science and TechnologyChongqing401331China College of Ecology and Environment Chongqing Resources and Environmental Protection of UniversityChongqing401331China China china Property Project Department of Dezhou Mining Property Service CenterShengli Oilfield Company of SinopecDezhou253000ShandongChina

Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacrylamide *** new drag reducers were synthesized from acrylamide(AM),sodium acrylate(Na AA)and a cationic modified monomer(AQAS1 or AQAS2)via aqueous solution polymerization,and the copolymers were named P(AM/Na AA/AQAS1)and P(AM/Na AA/AQAS2),*** structures of the drag reduction agents were confirmed by IR and1H NMR *** molecular weight(Mw)of P(AM/Na AA/AQAS1)was 1.79×10^(6)g/*** the copolymer concentration was 1000 mg/L and the flow rate was 45 L/min,in fresh water the highest drag reduction rate was 75.8%,in 10,000 mg/L Na Cl solution the drag reduction rate decreased to 72.9%.The molecular weight of P(AM/Na AA/AQAS2)was 3.17×10^(6)g/*** the copolymer concentration was500 mg/L and the flow rate was 45 L/min,the drag reduction rate reached 75.2%,and in 10,000 mg/L Na Cl solution the drag reduction rate was 73.3%,decreased by approximately 1.9%.The drag reduction rate for partially hydrolyzed polyacrylamide(HPAM)was also investigated,and the results showed that the drag reduction rates for 500 and 1000 mg/L HPAM solutions were merely 43.2%and 49.0%in brine,*** with HPAM,both of the above copolymers presented better drag reduction capacities.

关键词： Shale gas Slick water Drag reducer Modified monomer Copolymerization

Capacitor Voltage Imbalance Mechanism and Balancing Control of MMC When Riding Through PTG Fault

在线全文

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2024年第2期10卷 778-785页

作者： Zhen He Maozeng Lu Lijun Hang Pingliang Zeng Yanhua Liu Hangzhou Dianzi University Hangzhou 310018China Shandong University of technology Zibo 255000China State Grid Hangzhou Power Supply company State GridHangzhou 310000China

Modular multilevel converter (MMC) based fault ride through (FRT) control is a promising solution to deal with the pole-to-ground (PTG) fault in high voltage direct current (HVDC) system. However, when MMC switches to the FRT control, capacitor voltage imbalance between upper and lower arms will occur, resulting in the deterioration of FRT performance. This letter provides a comprehensive analysis for the imbalance issue from the perspective of fundamental frequency circulating current (FFCC). It is found the imbalance during FRT stage will not expand continuously, but converge to a certain value gradually. The specific imbalance degree is closely associated with the amplitude of FFCC. In order to solve the imbalance issue, an open-loop balancing control is proposed. By introducing a fundamental frequency feedforward item to the inherent circulating current control, the proposed method can not only balance the capacitor voltages, but also minimize the amplitude of FFCC, and consequently the power loss of MMC during FRT process can be reduced. Finally, simulation results of PSCAD/ EMTDC verify the validity of theoretical analysis.

关键词： Balancing control capacitor voltage imbalance FFCC FRT control HVDC system PTG fault

A review of reservoir damage during hydraulic fracturing of deep and ultra-deep reservoirs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum science 2024年第1期21卷 384-409页

作者： Kun Zhang Xiong-Fei Liu Dao-Bing Wang Bo Zheng Tun-Hao Chen Qing Wang Hao Bai Er-Dong Yao Fu-Jian Zhou National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing102249China School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing102617China Tuha Downhole Operation company CNPC Xibu Drilling Engineering Company LimitedShanshan838200XinjiangChina

Deep and ultra-deep reservoirs have gradually become the primary focus of hydrocarbon exploration as a result of a series of significant discoveries in deep hydrocarbon exploration *** reservoirs present unique challenges due to their deep burial depth(4500-8882 m),low matrix permeability,complex crustal stress conditions,high temperature and pressure(HTHP,150-200℃,105-155 MPa),coupled with high salinity of formation ***,the costs associated with their exploitation and development are exceptionally *** deep and ultra-deep reservoirs,hydraulic fracturing is commonly used to achieve high and stable *** hydraulic fracturing,a substantial volume of fluid is injected into the ***,statistical analysis reveals that the flowback rate is typically less than 30%,leaving the majority of the fluid trapped within the ***,hydraulic fracturing in deep reservoirs not only enhances the reservoir permeability by creating artificial fractures but also damages reservoirs due to the fracturing fluids *** challenging“three-high”environment of a deep reservoir,characterized by high temperature,high pressure,and high salinity,exacerbates conventional forms of damage,including water sensitivity,retention of fracturing fluids,rock creep,and proppant *** addition,specific damage mechanisms come into play,such as fracturing fluid decomposition at elevated temperatures and proppant diagenetic reactions at HTHP ***,the foremost concern in deep oil and gas development lies in effectively assessing the damage inflicted on these reservoirs by hydraulic fracturing,comprehending the underlying mechanisms,and selecting appropriate ***'s noteworthy that the majority of existing studies on reservoir damage primarily focus on conventional reservoirs,with limited attention given to deep reservoirs and a lack of systematic *** light of this,our approach entails initially summarizin

关键词： Artificial fracture Deep and ultra-deep reservoir Fracture conductivity Fracturing fluid Hydraulic fracturing Reservoir damage

Excess pore pressure behavior and evolution in deep coalbed methane reservoirs

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining science and technology 2024年第6期34卷 763-781页

作者： Changqing Liu Zhaobiao Yang Yong Qin Xia Yan Yunhai Wang Zhe Wang Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process Ministry of EducationChina University of Mining and TechnologyXuzhou 221008China School of Resources and Geosciences China University of Mining and TechnologyXuzhou 221116China National Engineering Research Center of Coalbed Methane Development&Utilization Beijing 100095China Petrochina Coalbed Methane company Limited Beijing 102200China SINOPEC East china Oil and Gas company Nanjing 210000China

Deep coalbed methane(DCBM),an unconventional gas reservoir,has undergone significant advancements in recent years,sparking a growing interest in assessing pore pressure dynamics within these *** some production data analysis techniques have been adapted from conventional oil and gas wells,there remains a gap in the understanding of pore pressure generation and evolution,particularly in wells subjected to large-scale hydraulic *** address this gap,a novel technique called excess pore pressure analysis(EPPA)has been introduced to the coal seam gas industry for the first time to our knowledge,which employs dual-phase flow principles based on consolidation *** technique focuses on the generation and dissipation for excess pore-water pressure(EPWP)and excess pore-gas pressure(EPGP)in stimulated deep coal *** have been developed respectively and numerical solutions have been provided using the finite element method(FEM).Application of this model to a representative field example reveals that excess pore pressure arises from rapid loading,with overburden weight transferred under undrained condition due to intense hydraulic fracturing,which significantly redistributes the weight-bearing role from the solid coal structure to the injected fluid and liberated gas within artificial pores over a brief ***,field application indicates that the dissipation of EPWP and EPGP can be actually considered as the process of well production,where methane and water are extracted from deep coalbed methane wells,leading to consolidation for the artificial ***,history matching results demonstrate that the excess-pressure model established in this study provides a better explanation for the declining trends observed in both gas and water production curves,compared to conventional practices in coalbed methane reservoir engineering and petroleum *** research not only enhances the understanding of DCBM re

关键词： Deep coalbed methane Consolidation Excess pore-water pressure Excess pore-gas pressure Production data analysis

The influence of patterned microporous layer on the proton exchange membrane fuel cell performances

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 6095-6101页

作者： Shunzhong Wang Kadi Hu Wei Chen Yali Cao Linan Wang Zhichang Wang Lirui Cui Mingzheng Zhou Wei Zhu Hui Li Zhongbin Zhuang State Key Lab of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China State Power Investment Corporation Hydrogen Energy company Ltd.Beijing 102600China Beijing Advanced Innovation Center for Soft Matter science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Energy Environmental Catalysis Beijing University of Chemical TechnologyBeijing 100029China

The ordered membrane electrode assembly(MEA)has gained much attention because of its potential in improving mass ***,a comprehensive study was conducted on the influence of the patterned microporous layer(MPL)on the proton exchange membrane fuel cell *** patterned MPL is employed,grooves are generated between the catalyst layer and the gas diffusion *** is found that the grooves do not increase the contact resistance,and it is beneficial for water *** the MEA works under low humidity scenarios,the MEA with patterned MPL illustrated higher performance,due to the reduced inner resistance caused by improved water retention,leading to increased ionic ***,when the humidity is higher than 80%or working under high current density,the generated water accumulated in the grooves and hindered the oxygen mass transport,leading to a reduced MEA performance.

关键词： microporous layer patterned proton exchange membrane fuel cell mass transport humidity water reduction

Evolution of microstructure and texture of AZ80 magnesium alloy under hot torsion with constant decreasing temperature rate

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2024年第4期12卷 1619-1637页

作者： Yongbiao Yang Jinxuan Guo Cuiying Wang Wenxuan Jiang Zhimin Zhang Qiang Wang Xing Zhang College of Materials science and Engineering North University of ChinaLane 3Xueyuan RoadTaiyuanShanxi 030051China North Hongyang mechanical and electronic limited company of Henan Province China

Hot torsion tests for AZ80 magnesium alloy were carried out in the temperature range of 380℃-260℃,with a constant decreasing temperature rate of 10℃/s in order to weaken the basal texture and refine the *** results indicated that the average grain sizes were refined forming gradient structure with increasing specimen radial position from center(12.2-5.4μm),and that the initial basal texture intensity of the extruded magnesium alloy was weakened from 46.2 to ***,the extension twins(ETs)could be disintegrated from the twins forming separated twins with smaller ***,ETs with the same twin variant intersecting with each other could be coalesced forming grains with similar orientation,while ETs with different twin variants were separated by twins boundaries contributing to grain ***,in addition to the conventional continuous dynamic recrystallized(CDRX)grains with 30˚orientation rotated around C-axis of the parent grains,CDRXed grains with 30˚rotation around a-axis and random rotation axis were also ***,the CDRX evolution induced twins were also elaborated,exhibiting the complex competition between CDRX and *** torsion deformation with constant decreasing temperatures rate is an effective way of grain refinement and texture modification.

关键词： Texture Microstructure Hot torsion Decreasing temperature AZ80

Impact of Osmotic Pressure on Seepage in Shale Oil Reservoirs

在线全文

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2024年第6期20卷 1365-1379页

作者： Lijun Mu Xiaojia Xue Jie Bai Xiaoyan Li Xueliang Han Oil and Gas technology Research Institute PetroChina Changqing Oilfield CompanyXi’an710018China

Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally *** tests and field trials have underscored the efficacy of fracturing fluid imbibition during the shut-in phase in augmenting shale oil *** conventional reservoirs,shale oil reservoirs exhibit characteristics such as low porosity,low permeability,and rich content of organic matter and clay ***,the osmotic pressure effects occurring between high-salinity formation water and low-salinity fracturing fluids are *** current understanding of the mobilization patterns of crude oil in micro-pores during the imbibition process remains nebulous,and the mechanisms underpinning osmotic pressure effects are not fully *** study introduces a theoretical approach,by which a salt ion migration control equation is derived and a mathematical model for spontaneous imbibition in shale is introduced,which is able to account for both capillary and osmotic *** indicate that during the spontaneous imbibition of low-salinity fluids,osmotic effects facilitate the migration of external fluids into shale pores,thereby complementing capillary forces in displacing shale *** considering both capillary and osmotic pressures,the calculated imbibition depth increases by 12%compared to the case where only capillary forces are *** salinity difference between the reservoir and the fracturing fluids significantly influences the imbibition *** for the shutin phase reveal that the pressure between the matrix and fractures reaches a dynamic equilibrium after 28 days of *** the production phase,the maximum seepage distance in the target block is approximately 6.02 m.

关键词： Shale oil osmotic pressure numerical simulation effective seepage distance

Stress Concentration Effect in Interface Between Conductor and Epoxy Resin in Coaxial Components of Power Equipment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2024年第1期10卷 412-420页

作者： Chuang Wang Kang Lei Qing Sun Hui Li Jiawei Zhang Lang Zhao Zongren Peng School of Electrical Engineering Xi’an University of TechnologyXi’an 710054China Xi’an Power Supply company State Grid Shaanxi Electric Power CompanyXi’an 710032China State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an 710049China

The spacer used in gas insulated switchgear(GIS)plays a vital role in its safe *** mismatch of mechanical properties between conductor and insulating material in spacers results in stress concentration at the interface between *** a hydrostatic test,mechanical damages are often initiated from the *** this paper,the stress between aluminum conductors and epoxy resin is studied by using a simplified coaxial structure *** measurement system and finite element simulation are used to explore the generation of stress and strain during curing and *** real-time measurement of strain at the interface shows that the residual strain in the entire process is primarily generated during the cooling ***,the temperature and stress/strain distribution at the interface during the cooling stage are further studied,and combined with experiments and *** consistency between the finite element simulation and the experimental measurement results verifies the validity of the simulation method *** results show that the maximum of the first principal stress generated during the cooling stage of the production process is concentrated on the upper and lower edges of the interface which is critical to the impact of the production quality of the spacer.

关键词： Epoxy resin GIS interface stress/strain distribution

Multi-surrogate framework with an adaptive selection mechanism for production optimization

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum science 2024年第1期21卷 366-383页

作者： Jia-Lin Wang Li-Ming Zhang Kai Zhang Jian Wang Jian-Ping Zhou Wen-Feng Peng Fa-Liang Yin Chao Zhong Xia Yan Pi-Yang Liu Hua-Qing Zhang Yong-Fei Yang Hai Sun School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Qingdao University of technology Qingdao266580ShandongChina College of science China University of PetroleumQingdao266580ShandongChina Zepu Oil and Gas Development Department PetroChina Tarim Oilfield CompanyKorla841000XinjiangChina Hainan Branch of CNOOC Ltd Haikou70311HainanChina

Data-driven surrogate models that assist with efficient evolutionary algorithms to find the optimal development scheme have been widely used to solve reservoir production optimization ***,existing research suggests that the effectiveness of a surrogate model can vary depending on the complexity of the design problem.A surrogate model that has demonstrated success in one scenario may not perform as well in *** the absence of prior knowledge,finding a promising surrogate model that performs well for an unknown reservoir is ***,the optimization process often relies on a single evolutionary algorithm,which can yield varying results across different *** address these limitations,this paper introduces a novel approach called the multi-surrogate framework with an adaptive selection mechanism(MSFASM)to tackle production optimization *** consists of two *** the first stage,a reduced-dimensional broad learning system(BLS)is used to adaptively select the evolutionary algorithm with the best performance during the current optimization *** the second stage,the multi-objective algorithm,non-dominated sorting genetic algorithm II(NSGA-II),is used as an optimizer to find a set of Pareto solutions with good performance on multiple surrogate models.A novel optimal point criterion is utilized in this stage to select the Pareto solutions,thereby obtaining the desired development schemes without increasing the computational load of the numerical *** two stages are combined using sequential transfer *** the two most important perspectives of an evolutionary algorithm and a surrogate model,the proposed method improves adaptability to optimization problems of various reservoir *** verify the effectiveness of the proposed method,four 100-dimensional benchmark functions and two reservoir models are tested,and the results are compared with those obtained by six other surrogate-model-based *** res

关键词： Production optimization Multi-surrogate models Multi-evolutionary algorithms Dimension reduction Broad learning system