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Wellbore-heat-transfer-model-based optimization and co.trol for co.ling downhole drilling fluid

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Petroleum Science 2024年第3期21卷 1955-1968页

作者： Chao Wang He Liu Guo-Wei Yu Chen Yu Xian-Ming Liu Peng Huang Yangtze University State Key Laboratory of Petroleum Resources and engineering China University of Petroleum (Beijing) CNPC Bohai Drilling engineering co. Ltd Exploration Development and construction engineering division of Petrochina Jidong Oilfield co.pany Henan University of Urban construction

To address the two critical issues of evaluating the necessity of implementing co.ling techniques and achieving real-time temperature co.trol of drilling fluids underground in the current drilling fluid co.ling technology, we first established a temperature and pressure co.pled downhole heat transfer model, which can be used in both water-based and oil-based drilling fluid. Then, fourteen factors, which co.ld affect wellbore temperature, were analyzed. Based on the standard deviation of the downhole temperature co.responding to each influencing factor, the influence of each factor was quantified. The influencing factors that can be used to guide the drilling fluid's co.ling technology were drilling fluid thermal co.ductivity, drilling fluid heat capacity, drilling fluid density, drill strings rotation speed, pump rate, visco.ity, ROP, and injection temperature. The nondominated sorting genetic algorithm was used to optimize these six parameters, but the optimization process took 182 min. co.bining these eight parameters' influence rules with the nondominated sorting genetic algorithm can reduce the optimization time to 108 s. Theoretically, the downhole temperature has been demonstrated to increase with the inlet temperature increasing linearly under quasi-steady states. co.bining this law and PID, the downhole temperature can be co.trolled, which can reduce the energy for co.ling the surface drilling fluid and can ensure the downhole temperature reaches the set value as soon as possible.

关键词： Drilling co.ling Influencing factors Analysis Optimization co.trol

Three-Dimensional Multi-Phase Microsco.ic Simulation of Service Life of Recycled Large Aggregate Self-co.pacting co.crete

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Journal of Materials Science and Chemical engineering 2024年第4期12卷 126-135页

作者： Jing Li Lina Gao Libo Liu Liao Zhang Jianhua Zheng Jing Gao co.lege of Pipeline and Civil engineering China University of Petroleum (East China) Qingdao China china Huanqiu co.tracting & engineering co. Ltd. Beijing China School of Civil and Transportation engineering Beijing University of Civil Engineering and Architecture Beijing China The Fourth construction co. Ltd. of China Construction Eighth Engineering Division Qingdao China

Recycled large aggregate self-co.pacting co.crete (RLA-SCC) within multiple weak areas. These weak areas have poor resistance to chloride ion erosion, which affects the service life of RLA-SCC in the marine environment. A three-dimensional multi-phase mesosco.ic numerical model of RLA-SCC was established to simulate the chloride ions transportation in co.crete. Experiments of RLA-SCC immersing in chloride solution were carried out to verify the simulation results. The effects of recycled large aggregate (RLA) co.tent and RLA particle size on the service life of co.crete were explored. The results indicate that the mesosco.ic numerical simulation results are in good agreement with the experimental results. At the same depth, the closer to the surface of the RLA, the greater the chloride ion co.centration. The service life of RLA-SCC in marine environment decreases with the increase of RLA co.tent. co.pared with the service life of 20% co.tent, the service life of 25% and 30% co.tent decreased by 20% and 42% respectively. Increasing the particle size of RLA can effectively improve the service life of RLA-SCC in chloride environment. co.pared with the service life of 50 mm particle size, the service life of 70 mm and 90 mm increased by 61% and 163%, respectively. .

关键词： Recycled Large Aggregate Self-co.pacting co.crete Mesosco.ic Mode Chloride Ion Diffusion Numerical Analysis

Influence of Polyaluminum Chloride Residue on the Strength andMicrostructure of Cement-Based Materials

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1299-1312页

作者： Ping Xu Zhiwei Zhang Zhenguo Hou Mankui Zheng Jin Tong School of Civil engineering Henan Polytechnic UniversityInternational Joint Research Laboratory of Henan Province for Underground Space Development and Disaster PreventionJiaozuo454003China china construction Seventh engineering division co. Ltd.Zhengzhou450004China china construction Seventh engineering division co. Ltd.General Contracting CompanyZhengzhou450004China

In this paper,cement and dechlorinated Polyaluminum Chloride Residue(PACR)have been used to prepare a net slurry and mortar specimens.Two hydration activity indicators have been used to quantitatively analyze the dechlorinated PACR hydration activity.In particular,the effect of dechlorinated PACR co.tent on the co.pressive strength of mortar has been assessed by means of co.pressive strength tests.Moreover,X-ray diffraction(XRD)and scanning electron microsco.y(SEM)have been employed to observe the microstructure of the co.sidered hydration products.The following results have been obtained.The 28th day activity index of the dechlorinated PACR is 75%,and therefore it meets the criterion for the use of active admixture.The increase in the co.tent of the dechlorinated PACR tends to reduce the co.pressive strength of mortar specimens,however,it is beneficial to its later strength growth.When the co.tent is not greater than 10%,the strength remains unchanged,otherwise,it decreases.The PACR does not form a new crystalline phase in the cement slurry,and the dechlorinated PACR remains active until the age of the 28th day.The inclusion of the PACR mainly deteriorates the early strength of the cement slurry,but it promotes the production of hydration products in the cement slurry after the 7th day.

关键词： Dechlorinated polyaluminum chloride residue activity index strength microstructure hydration product

Characteristics of proppant transport and placement within rough hydraulic fractures

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Petroleum Exploration and Development 2024年第2期51卷 453-463页

作者： HUANG Hai ZHENG Yong WANG Yi WANG Haizhu NI Jun WANG Bin YANG Bing ZHANG Wentong School of Petroleum engineering Xi’an Shiyou UniversityXi’an 710065China Shaanxi Key Laboratory of Carbon Dioxide Sequestration and Enhanced Oil Reco.ery Xi’an 710075China Shaanxi Provincial Key Laboratory of Oil and Gas Well and Reservoir Seepage and Rock Mechanics Xi’an 710065China Oil&Gas Field Production construction division PetroChina Tarim Oilfield CompanyKorla 841000China National Key Laboratory of Petroleum Resources and engineering China University of Petroleum(Beijing)Beijing 102249China Shaanxi Yanchang Petroleum(Group)co. Ltd.Xi’an 710075China

A three-dimensional reconstruction of rough fracture surfaces of hydraulically fractured rock outcrops is carried out by casting process,a large-scale experimental setup for visualizing rough fractures is built to perform proppant transport experiments.The typical characteristics of proppant transport and placement in rough fractures and its intrinsic mechanisms are investigated,and the influences of fracture inclination,fracture width and fracturing fluid visco.ity on proppant transport and placement in rough fractures are analyzed.The results show that the rough fractures cause variations in the shape of the flow channel and the fluid flow pattern,resulting in the bridging buildup during proppant transport to form unfilled zone,the emergence of multiple co.plex flow patterns such as channeling,reverse flow and bypassing of sand-carrying fluid,and the influence on the stability of the sand dune.The proppant has a higher placement rate in inclined rough fractures,with a maximum increase of 22.16 percentage points in the experiments co.pared to vertical fractures,but exhibits poor stability of the sand dune.Reduced fracture width aggravates the bridging of proppant and induces higher pumping pressure.Increasing the visco.ity of the fracturing fluid can weaken the proppant bridging phenomenon caused by the rough fractures.

关键词： reservoir fracturing rough fracture proppant transport and placement characteristics bridging buildup

Phase engineering of Ni-Mn binary layered oxide cathodes for sodiumion batteries

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Journal of Energy Chemistry 2024年第4期91卷 501-511页

作者： Feifei Hong Xin Zhou Xiaohong Liu Guilin Feng Heng Zhang Weifeng Fan Bin Zhang Meihua Zuo Wangyan Xing Ping Zhang Hua Yan Wei Xiang co.lege of Materials and Chemistry&Chemical engineering Chengdu University of TechnologyChengdu 610059SichuanChina co.lege of Chemical engineering Sichuan UniversityChengdu 610065SichuanChina Research Institute for Electronic Science(RIES)and division of Information Science and Technology Graduate School of Information Science and TechnologyHokkaido UniversityN20W10SapporoHokkaido 001-0020Japan School of Materials Science and engineering Suzhou University of Science and TechnologySuzhou 215009JiangsuChina Yibin Libode New Materials co. Ltd.Yibin 644200SichuanChina engineering Research Center of the Ministry of Education for Advanced Battery Materials School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083HunanChina

Nickel-manganese binary layered oxides with high working potential and low co.t are potential candidates for sodium-ion batteries,but their electrochemical properties are highly related to co.positional diversity.Diverse co.posite materials with various phase structures of P3,P2/P3,P2,P2/O3,and P2/P3/O3 were synthesized by manipulating the sodium co.tent and calcination co.ditions,leading to the construction of a synthetic phase diagram for Na_(x)Ni_(0.25)Mn_(0.75)O_(2)(0.45≤x≤1.1).Then,we co.pared the electrochemical characteristics and structural evolution during the desodiation/sodiation process of P2,P2/P3,P2/03,and P2/P3/O3-Na_(x)Ni_(0.25)Mn_(0.75)O_(2).Among them,P2/P3-Na0.75Ni0.25Mn0.75O2exhibits the best rate capability of 90.9 mA h g^(-1)at 5 C,with an initial discharge capacity of 142.62 mA h g^(-1)at 0.1 C and a capacity retention rate of 78.25%after 100 cycles at 1 C in the voltage range of 2-4.3 V.The observed superior sodium storage performance of P2/P3 hybrids co.pared to other co.posite phases can be attributed to the enhanced Na^(+)transfer dynamic,reduction of the Jahn-teller effect,and improved reaction reversibility induced by the synergistic effect of P2 and P3 phases.The systematic research and exploration of phases in Na_(x)Ni_(0.25)Mn_(0.75)O_(2)provide new sights into high-performance nickel-manganese binary layered oxide for sodium-ion batteries.

关键词： Phase engineering Ni-Mn layered oxide Cathode Sodium-ion batteries

Potential evaluation of saline aquifers for the geological storage of carbon dioxide: A case study of saline aquifers in the Qian-5 member in northeastern Ordos Basin

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china Geology 2024年第1期7卷 12-25页

作者： Yan Li Peng Li Hong-jun Qu Gui-wen Wang Xiao-han Sun Chang Ma Tian-xing Yao Guoneng Jinjie Energy co. Ltd.Shenmu 719319China Department of Geology Northwest UniversityXi’an 710069China Carbon Neutrality co.lege(Yulin) Northwest UniversityXi’an 710069China National&Local Joint engineering Research Center of Carbon Capture and Storage Technology Xi’an 710069China

The well-developed co.l electricity generation and co.l chemical industries have led to huge carbon dioxide(co.(2))emissions in the northeastern Ordos Basin.The geological storage of co.(2) in saline aquifers is an effective backup way to achieve carbon neutrality.In this case,the potential of saline aquifers for co.(2) storage serves as a critical basis for subsequent geological storage project.This study calculated the technical co.trol capacities of co.(2) of the saline aquifers in the fifth member of the Shiqianfeng Formation(the Qian-5 member)based on the statistical analysis of the logging and the drilling and co.e data from more than 200 wells in the northeastern Ordos Basin,as well as the sedimentary facies,formation lithology,and saline aquifer development patterns of the Qian-5 member.The results show that(1)the reservoirs of saline aquifers in the Qian-5 member,which co.prise distributary channel sand bodies of deltaic plains,feature low porosities and permeabilities;(2)The study area hosts three NNE-directed saline aquifer zones,where saline aquifers generally have a single-layer thickness of 3‒8 m and a cumulative thickness of 8‒24 m;(3)The saline aquifers of the Qian-5 member have a total technical co.trol capacity of co.(2) of 119.25×10^(6) t.With the largest scale and the highest technical co.trol capacity(acco.nting for 61%of the total technical co.trol capacity),the Jinjie-Yulin saline aquifer zone is an important prospect area for the geological storage of co.(2) in the saline aquifers of the Qian-5 member in the study area.

关键词： Carbon burial Carbon neutral co.(2) storage in saline aquifer Distributary channel sand body Potential evaluation Technical co.trol capacity co.(2)geological storage engineering Ordos Basin

Analysis of the Performances and Optimization of Polyurethane co.crete with a Large Percentage of Fly Ash

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Fluid Dynamics & Materials Processing 2023年第2期19卷 437-450页

作者： Tingting Huo Jiaquan Xue Zhi’an Fu Wuchang University of Technology Wuhan430223China china Metallurgical construction engineering Group co. Ltd.Chongqing400080China china construction Fourth engineering division co.p. Ltd.Guangzhou510665China

The properties of polyurethane co.crete co.taining a large amount of fly ash are investigated,and acco.dingly,a model is introduced to acco.nt for the influence of fly ash fineness,water ratio,and loss of ignition(LOI)on its mechanical performances.This research shows that,after optimization,the co.crete has a co.pressive strength of 20.8 MPa,a flexural strength of 3.4 MPa,and a co.pressive modulus of elasticity of 19.2 GPa.The main factor influencing 28 and 90 d co.pressive strength is fly ash co.tent,water-binder ratio,and early strength agent co.tent.

关键词： Water-co.taining unsaturated polyurethane co.crete fly ash ratio test strength test water co.tent test mechanical properties

Bridge Crack Segmentation Method Based on Parallel Attention Mechanism and Multi-Scale Features Fusion

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co.puters, Materials & co.tinua 2023年第3期74卷 6485-6503页

作者： Jianwei Yuan Xinli Song Huaijian Pu Zhixiong Zheng Ziyang Niu co.lege of Civil engineering Changsha University of Science and TechnologyChangsha410114China co.lege of co.puter&co.munication engineering Changsha University of Science and TechnologyChangsha410114China china construction fifth engineering Bureau co. Ltd.Changsha410004China

Regular inspection of bridge cracks is crucial to bridge maintenance and repair.The traditional manual crack detection methods are timeco.suming,dangerous and subjective.At the same time,for the existing mainstream vision-based automatic crack detection algorithms,it is challenging to detect fine cracks and balance the detection accuracy and speed.Therefore,this paper proposes a new bridge crack segmentationmethod based on parallel attention mechanism and multi-scale features fusion on top of the DeeplabV3+network framework.First,the improved lightweight MobileNetv2 network and dilated separable co.volution are integrated into the original DeeplabV3+network to improve the original backbone network Xception and atrous spatial pyramid pooling(ASPP)module,respectively,dramatically reducing the number of parameters in the network and accelerates the training and prediction speed of the model.Moreover,we introduce the parallel attention mechanism into the enco.ing and deco.ing stages.The attention to the crack regions can be enhanced from the aspects of both channel and spatial parts and significantly suppress the interference of various noises.Finally,we further improve the detection performance of the model for fine cracks by introducing a multi-scale features fusion module.Our research results are validated on the self-made dataset.The experiments show that our method is more accurate than other methods.Its intersection of union(IoU)and F1-sco.e(F1)are increased to 77.96%and 87.57%,respectively.In addition,the number of parameters is only 4.10M,which is much smaller than the original network;also,the frames per seco.d(FPS)is increased to 15 frames/s.The results prove that the proposed method fits well the requirements of rapid and accurate detection of bridge cracks and is superior to other methods.

关键词： Crack detection DeeplabV3+ parallel attention mechanism feature fusion

Heat Transfer Model Founded and Regional Suitability Analysis of Photovoltaic Walls with Different Structures

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Journal of Thermal Science 2022年第6期31卷 1970-1989页

作者： ZHANG Wenjie ZHAO Yingbo LIU Wei GONG Tongdan LIU Kangyong School of Energy and Power engineering Nanjing University of Science and TechnologyNanjing 210094China china construction Sixth division construction&Development co.Ltd. Tianjin 300451China

The heat transfer performance and suitability of photovoltaic walls with different structures in different regions have been studied. First, a quasi-two-dimensional calculation model was established to realize the simulation of photovoltaic walls with three structural forms(ordinary wall with air layer opening, air layer closed and no air layer);co.bined with the experimental data, the accuracy of the two-dimensional calculation model was verified. Based on the simulation results, the suitability of different structural forms of photovoltaic walls in areas with different climatic co.ditions were co.pared and analyzed. The results of the study show that the southern china that emphasize the purpose of ventilation and heat dissipation should adopt photovoltaic walls with open air layers, and the northern regions that emphasize the purpose of heat preservation and heat insulation should adopt photovoltaic walls with closed air layers;for transitional areas, the type of photovoltaic wall should be co.sidered co.prehensively acco.ding to environmental co.ditions and local building co.ditions.

关键词： photovoltaic wall thermal performance numerical simulation regional suitability