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Wellbore-heat-transfer-model-based optimization and control for cooling 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 company Henan University of Urban construction

To address the two critical issues of evaluating the necessity of implementing cooling techniques and achieving real-time temperature control of drilling fluids underground in the current drilling fluid cooling technology, we first established a temperature and pressure coupled downhole heat transfer model, which can be used in both water-based and oil-based drilling fluid. Then, fourteen factors, which could affect wellbore temperature, were analyzed. Based on the standard deviation of the downhole temperature corresponding to each influencing factor, the influence of each factor was quantified. The influencing factors that can be used to guide the drilling fluid's cooling technology were drilling fluid thermal conductivity, drilling fluid heat capacity, drilling fluid density, drill strings rotation speed, pump rate, viscosity, ROP, and injection temperature. The nondominated sorting genetic algorithm was used to optimize these six parameters, but the optimization process took 182 min. combining 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. combining this law and PID, the downhole temperature can be controlled, which can reduce the energy for cooling the surface drilling fluid and can ensure the downhole temperature reaches the set value as soon as possible.

关键词： Drilling cooling Influencing factors Analysis Optimization control

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 content on the compressive strength of mortar has been assessed by means of compressive strength tests.Moreover,X-ray diffraction(XRD)and scanning electron microscopy(SEM)have been employed to observe the microstructure of the considered 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 content of the dechlorinated PACR tends to reduce the compressive strength of mortar specimens,however,it is beneficial to its later strength growth.When the content 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

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);combined 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 conditions were compared 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 considered comprehensively according to environmental conditions and local building conditions.

关键词： photovoltaic wall thermal performance numerical simulation regional suitability

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Three-Dimensional Multi-Phase Microscopic Simulation of Service Life of Recycled Large Aggregate Self-compacting concrete

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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 college of Pipeline and Civil Engineering China University of Petroleum (East China) Qingdao China china Huanqiu contracting & 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-compacting concrete (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 mesoscopic numerical model of RLA-SCC was established to simulate the chloride ions transportation in concrete. Experiments of RLA-SCC immersing in chloride solution were carried out to verify the simulation results. The effects of recycled large aggregate (RLA) content and RLA particle size on the service life of concrete were explored. The results indicate that the mesoscopic 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 concentration. The service life of RLA-SCC in marine environment decreases with the increase of RLA content. compared with the service life of 20% content, the service life of 25% and 30% content decreased by 20% and 42% respectively. Increasing the particle size of RLA can effectively improve the service life of RLA-SCC in chloride environment. compared 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-compacting concrete Mesoscopic Mode Chloride Ion Diffusion Numerical Analysis

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 Recovery 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 viscosity 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 complex 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 compared 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 viscosity 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

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Effects of Water-retaining Agents on Growth, development, Yield and Quality of Soybean under Drought Stress

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Plant Diseases and Pests 2024年第3期15卷 34-39页

作者： Hui XIA Yan ZHANG Yun HAN Shasha HU Hengbin ZHANG Agricultural Science Research Institute of the Fourth division of the Xinjiang Production and construction corps Ili 835219China

[Objectives]The paper was to explore the effects of different doses of water-retaining agent on the growth and development indicators,yield and quality of soybean plants subjected to drought stress.[Methods]The effects of drought stress(MDS)and drought stress with low(MDS-L),medium(MDS-M)and high doses(MDS-H)of the water-retaining agent on the growth and development indicators,root activity,MDA content,antioxidant enzyme activity,yield and quality of soybean were studied by field plot test,with the normal water supply serving as the control(CK).[Results]In response to drought stress,the plant height,stem diameter,and yield of soybean exhibited a notable decline.Additionally,the contents of protein,fat,linoleic acid,and linolenic acid in seeds demonstrated a significant reduction.conversely,the root activity and antioxidant enzyme activity exhibited a noticeable decline,while the MDA content exhibited an increase.The application of varying doses of the water-retaining agent was found to significantly enhance soybean growth,stimulate root activity,and elevate antioxidant enzyme activity,while concurrently reducing MDA content.The observed effects were found to be dose-dependent,with the greatest effects observed at the highest dose.In comparison to MDS,the yields of soybean in the MDS-L,MDS-M,and MDS-H treatments exhibited a 18.38%,25.58%,and 46.26%increase,respectively.Additionally,the content of protein,fat,linoleic acid,and linolenic acid in seeds demonstrated a notable enhancement.[conclusions]The application of the water-retaining agent has been demonstrated to significantly promote the growth of soybean plants under conditions of drought stress,resulting in an improvement in both the yield and the quality of the soybean crop.The recommended dosage of the water-retaining agent is 3.3 kg/667 m 2.

关键词： Soybean Water-retaining agent Yield Quality Growth and development Antioxidant enzyme activity

Interfacial engineering of the layered oxide cathode materials for sodium-ion battery

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Nano Research 2024年第3期17卷 1441-1464页

作者： Quanqing Zhao Ruru Wang Ming Gao Faheem KButt Jianfeng Jia Haishun Wu Youqi Zhu Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials ScienceShanxi Normal UniversityTaiyuan 030032China Metals and Chemistry Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China Department of Physics Division of Science and TechnologyUniversity of EducationLahore 54770Pakistan Research Center of Materials Science Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green ApplicationsBeijing Institute of TechnologyBeijing 100081China

The layered metal oxides are reviewed as the hopeful cathode materials for high-performance sodium-ion batteries(SIBs)due to their large theoretical capacity,favorable two-dimensional(2D)ion diffusion channel,and simple manipuility.However,their cycling stability,rate capability,and thermal stability are still significantly concerned and highlighted before further practical application.The chemical,mechanical and electrochemical stability of the cathode–electrolyte interfaces upon cycling is of great significance.Herein,the unique structural and electrochemical properties of the layered oxide cathode materials for SIB are reviewed.The mechanism of bulk/surface degradation induced by oxygen evolution,phase transition,microcrack,and electrolyte decomposition is thoroughly understood.Furthermore,the interfacial engineering to construct stable interface through various effective methods is fully discussed.The future outlook and challenges for interfacial engineering in this filed are also summarized.This review should shed light on the rational design and construct of robust interface for applications of superior layered oxide cathodes in SIB and may suggest future research directions.

关键词： interfacial engineering sodium-ion battery layered oxide electrolyte interface

Different timing for abdominal paracentesis catheter placement and drainage in severe acute pancreatitis complicated by intraabdominal fluid accumulation

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 134-142页

作者： Rui Chen Hua-Qiang Chen Rui-Die Li Hui-Min Lu Department of General Surgery Chengdu Sixth People’s HospitalChengdu 610058Sichuan ProvinceChina West china Center of Exellence for Pancreatitis Institute of Integrated Traditional Chinese and Western MedicineWest ChinaDivision of Pancreatic SurgeryDepartment of General SurgeryWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina HospitalSichuan University

BACKGROUND Non-surgical methods such as percutaneous drainage are crucial for the treatment of patients with severe acute pancreatitis(SAP).However,there is still an ongoing debate regarding the optimal timing for abdominal paracentesis catheter place-ment and drainage.AIM To explore the influence of different timing for abdominal paracentesis catheter placement and drainage in SAP complicated by intra-abdominal fluid accumu-lation.METHODS Using a retrospective approach,184 cases of SAP complicated by intra-abdominal fluid accumulation were enrolled and categorized into three groups based on the timing of catheter placement:group A(catheter placement within 2 d of symptom onset,n=89),group B(catheter placement between days 3 and 5 after symptom onset,n=55),and group C(catheter placement between days 6 and 7 after symptom onset,n=40).The differences in progression rate,mortality rate,and the number of cases with organ dysfunction were compared among the three groups.RESULTS The progression rate of group A was significantly lower than those in groups B and groups C(2.25%vs 21.82%and 32.50%,P0.05).At postoperative day 3,the levels of C-reactive protein(55.41±19.32 mg/L vs 82.25±20.41 mg/L and 88.65±19.14 mg/L,Pcompared to those in groups B and group C.The length of hospital stay in group A was significantly lower than

关键词： Abdominal paracentesis catheter drainage Timing Severe acute pancreatitis Intra-abdominal fluid Application value

Post-disaster spatial reconstruction from the perspective of a rural settlement niche in the upper reaches of the Minjiang River

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Journal of Mountain Science 2024年第5期21卷 1630-1646页

作者： LIU Yanguo WANG Li ZOU Qiang LI Jingji LU Yafeng LI Lin XU Binni WANG Lihui Tianfu Institute of Research and Innovation Southwest University of Science and TechnologyChengdu 610299China Mianyang Science and Technology City division the National Remote Sensing Center of ChinaSouthwest University of Science and TechnologyMianyang 621010China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China State Key Laboratory of Geo-hazard Prevention and Geo-environment Protection(Chengdu University of Technology) Chengdu 610059China Tianfu New Area Park City construction Bureau Chengdu Municipal Bureau of Planning and Nature ResourcesChengdu 610218China

Post-disaster recovery and reconstruction provide an effective way to reduce the disaster vulnerability of, and promote leapfrog development in, an affected area. To date, studies that have used administrative boundaries to investigate the reconstruction of settlement space have not been able to clearly define the real boundaries of land use changes or quantify the degree of response to the ‘Build-Back-Better’ initiative, and have lacked any consideration of the fourth reconstruction stage–development period(10 years). This study constructed a mountain settlement niche and analyzed the characteristics, spatial reconstruction, and drivers of rural settlements during 2009–2019 in the upper reaches of the Minjiang River, southwest china. The results showed the following:(1) Natural factors were the basis for the formation and development of mountain settlement niches. The scale of the settlement niche and its land use structure depended on the physical geography features and the ethnic farming and grazing traditions. The settlement niche provided a realistic boundary for the spatial reconstruction.(2) The layout of residential land around cropland was the common feature of the mountain settlement niche. Of all the land use types, the roads and rural residential lands showed the most change over the 10 years;13,860 residential patches increased in size and 4,742 patches were abandoned.(3) The area of orchards, planted to reconstruct the economy in the mountains, increased by nearly 2.5 times.(4) collapses, landslides, and debris flow disasters and the ecological red line influenced the spatial reconstruction. While the main focus of post-disaster recovery is spatial reconstruction, initiatives should include economic and spiritual recovery, and should also achieve sustainable development of the region.

关键词： Rural settlements Spatial reconstruction Settlement niche Post-Wenchuan Earthquake Reconstruction Southwest china

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