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Calculation of Mass Concrete Temperature and Creep Stress under the Influence of Local Air Heat Transfer

Computer Modeling in engineering & Sciences 2024年第9期140卷 2977-3000页

作者： Heng Zhang Chao Su Xiaohu Chen Zhizhong Song Weijie Zhan Academy of Science and Technology Changjiang Institute of Survey Planning Design and ResearchWuhan430010China College of Water Conservancy and Hydropower engineering Hohai UniversityNanjing210098China Chief engineer office Wujiang Company of Goupitan Power Construction CooperationYuqing564408China

Temperature-induced cracking during the construction of mass concrete is a significant *** simulations of concrete temperature have primarily assumed that the concrete is placed in an open *** problem of heat transfer between the air and concrete has been simplified to the concrete’s heat dissipation ***,in the case of tubular concrete structures,where air inlet and outlet are relatively limited,the internal air temperature does not dissipate promptly to the external environment as it *** accurately simulate the temperature and creep stress in tubular concrete structures with enclosed air spaces during construction,we establish an air–concrete coupled heat transfer model according to the principles of conjugate heat transfer,and the accuracy of the model is verified through ***,we conduct a case study to analyze the impact of airflow within the ship lock corridor on concrete temperature and creep *** results demonstrate that enhancing airflow within the corridor can significantly reduce the maximum concrete *** with cases in which airflow within the corridor is neglected,the maximum concrete temperature and maximum tensile stress can be reduced by 12.5℃ and 0.7 MPa,respectively,under a wind speed of 4 m/*** results of the traditional calculation method are relatively close to those obtained at a wind speed of 1 m/***,the temperature reduction process in the traditional method is faster,and the method yields greater tensile stress values for the corridor location.

关键词： Conjugate heat transfer temperature field mass concrete creep stress

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Calculation of Mass Concrete Temperature Containing Cooling Water Pipe Based on Substructure and Iteration Algorithm

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工程与科学中的计算机建模(英文) 2024年第1期138卷 813-826页

作者： Heng Zhang Chao Su Zhizhong Song Zhenzhong Shen Huiguang Lei Changjiang Institute of Survey PlanningDesign and ResearchWuhan430010China College ofWater Conservancy and Hydropower engineering Hohai UniversityNanjing210098China Chief engineer office Wujiang Company of Goupitan Power Construction CooperationYuqing564408China

Mathematical physics equations are often utilized to describe physical phenomena in various fields of science and *** such equation is the Fourier equation,which is a commonly used and effective method for evaluating the effectiveness of temperature control measures for mass *** important measure for temperature control in mass concrete is the use of cooling water ***,the mismatch of grids between large-scale concrete models and small-scale cooling pipe models can result in a significant waste of calculation time when using the finite element ***,the temperature of the water in the cooling pipe needs to be iteratively calculated during the thermal transfer *** substructure method can effectively solve this problem,and it has been validated by *** Abaqus/Python secondary development technology provides engineers with enough flexibility to combine the substructure method with an iteration algorithm,which enables the creation of a parametric modeling calculation for cooling water *** paper proposes such a method,which involves iterating the water pipe boundary and establishing the water pipe unit substructure to numerically simulate the concrete temperature field that contains a cooling water *** verify the feasibility and accuracy of the proposed method,two classic numerical examples were *** results showed that this method has good applicability in cooling pipe *** the value of the iteration parameterαis 0.4,the boundary temperature of the cooling water pipes can meet the accuracy requirements after 4∼5 iterations,effectively improving the computational ***,this approach provides a useful tool for engineers to analyze the temperature control measures accurately and efficiently for mass concrete,such as cooling water pipes,using Abaqus/Python secondary development.

关键词： Fourier equation cooling water pipe mass concrete iteration algorithm

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Auto-tuning PVT data using multi-objective optimization: Application of NSGA-Ⅱ algorithm

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Petroleum 2024年第1期10卷 135-149页

作者： Abdolhadi Zarifi Mohammad Madani Mohammad Jafarzadegan Reservoir engineering Systems Petroleum Engineering Department Main Office Building of National Iranian South Oil Company (NISOC) Combined Planning Management National Iranian Oil Company (NIOC) Reservoir engineering Division Petroleum Engineering Department Petroleum Engineering and Development Company (PEDEC)

Reservoir simulation is known as perhaps the most widely used, accurate, and reliable method for field development in the petroleum industry. An integral part of a reliable reservoir simulation process is to consider robust and rigorous tuned EOS models. Traditionally, EOS models are tuned iteratively through arduous workflows against experimental PVT data. However, this comes with a number of drawbacks such as forcingly using weight factors, which upon alteration adversely affects the optimization *** objective of the current work is thus to introduce an auto-tune PVT matching tool using NSGA-II multi-objective optimization. In order to illustrate the robustness of the presented technique, three different PVT samples are used, including two black-oil and one gas condensate sample. We utilize PengRobinson EOS during all the manual and auto-tuning processes. Comparison of auto-tuned EOS-generated results with those of experimental and computed statistical error values for these samples clearly show that the proposed method is robust. In addition, the proposed method, contrary to the manual matching process, provides the engineer with several matched solutions, which allows them to select a match based on the engineering background to be best amenable to the problem at hand. In addition, the proposed technique is fast, and can output several solutions within less time compared to the traditional manual matching method.

关键词： Auto-tuning PVT Equation of state NSGA-II Multi-objective optimization

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A practical application of photogrammetry to performing rib characterization measurements in an underground coal mine using a DSLR camera

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International Journal of Mining Science and Technology 2017年第1期27卷 83-90页

作者： Brent A.Slaker Khaled M.Mohamed Mining engineer Ground Control Branch NIOSH Office of Mine Safety and Health ResearchPittsburghPAUSA

Understanding coal mine rib behavior is important for inferring pillar loading conditions as well as ensuring the safety of miners who are regularly exposed to ribs. Due to the variability in the geometry of underground openings and ground behavior, point measurements often fail to capture the true movement of mine workings. Photogrammetry is a potentially fast, cheap, and precise supplemental measurement tool in comparison to extensometers, tape measures, or laser range meters, but its application in underground coal has been limited. The practical use of photogrammetry was tested at the Safety Research Coal Mine, National Institute for Occupational Safety and Health(NIOSH). A commercially available, digital single-lens reflex(DSLR) camera was used to perform the photogrammetric surveys for the experiment. Several experiments were performed using different lighting conditions, distances to subject,camera settings, and photograph overlaps, with results summarized as follows: the lighting method was found to be insignificant if the scene was appropriately illuminated. It was found that the distance to the subject has a minimal impact on result accuracy, and that camera settings have a significant impact on the photogrammetric quality of images. An increasing photograph resolution was preferable when measuring plane orientations; otherwise a high point cloud density would likely be excessive. Focal ratio(F-stop) changes affect the depth of field and image quality in situations where multiple angles are necessary to survey cleat orientations. Photograph overlap is very important to proper three-dimensional reconstruction, and at least 60% overlap between photograph pairs is ideal to avoid unnecessary post-processing. The suggestions and guidelines proposed are designed to increase the quality of photogrammetry inputs and outputs as well as minimize processing time, and serve as a starting point for an underground coal photogrammetry study.

关键词： Photogrammetry Coal mining Underground Rib characterization

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Design concerns of room and pillar retreat panels

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International Journal of Mining Science and Technology 2017年第1期27卷 29-35页

作者： Klemetti Ted M. Sears Morgan M. Tulu Ihsan B. Mining engineer Ground Control Branch NIOSH Office of Mine Safety and Health ResearchPittsburghPAUSA

Why do some room and pillar retreat panels encounter abnormal conditions？ What factors deserve the most consideration during the planning and execution phases of mining and what can be done to mitigate those abnormal conditions when they are encountered7 To help answer these questions, and to determine some of the relevant factors influencing the conditions of room and pillar （R ＆ P） retreat min- ing entries, four consecutive R ＆ P retreat panels were evaluated. This evaluation was intended to rein- force the influence of topographic changes, depth of cover, multiple-seam interactions, geological conditions, and mining geometry. This paper details observations were made in four consecutive R ＆ P retreat panels and the data were collected from an instrumentation site during retreat mining. The pri- mary focus was on the differences observed among the four panels and within the panels themselves. The instrumentation study was initially planned to evaluate the interactions between primary and secondary support, but produced rather interesting results relating to the loading encountered under the current mining conditions. In addition to the obse^ation and ｜ll^trumentation, numerical modeling was per- formed to evaluate the stress condi~!ons. Both the LaModel 3.0 and Rocscience Phase 2 programs were used to evaluate these four panels, The results of both models indicated a drastic reduction in the vertical stresses experienced in these panels due to the full extraction mining in overlying seams when compared to the full overburden load. Both models showed a higher level of stress associated with the outside entries of the panels. These results agree quite well with the observations and instrumentation studies performed at the mine. These efforts provided two overarching conclusions concerning R ＆ P retreat mine planning and execution. The first was that there are four areas that should not be overlooked during R ＆ P retreat mining： topographic relief, multiple^seaPa str

关键词： Room and pillar Retreat mining Deep coverSafety Multiple seam

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Sediment retention by check dams in the Hekouzhen-Longmen Section of the Yellow River

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International Journal of Sediment Research 2008年第2期23卷 159-166页

作者： Da-Chuan RAN1,2,Quan-Hua LUO3,Zu-Hao ZHOU4,Guo-Qing WANG5,and Xiao-Hua ZHANG2 1 Senior engineer,Xi’an University of Technology,Xi’an 710048,China 2 Senior engineer,Yellow River Institute of Hydraulic Research,Zhengzhou 450003,China 3 engineer ,Xifeng Soil and Water Conservation Experimental Station,Qingyang 745000,China 4 Senior engineer,China Institute of Water Resources and Hydropower Research,Beijing 100038,China 5 Senior engineer,Flood prevention office of YRCC,Zhengzhou 450003,China Senior engineer Xi'an University of Technology Xi'an 710048 China Senior engineer Yellow River Institute of Hydraulic Research Zhengzhou 450003 China engineer Xifeng Soil and Water Conservation Experimental Station Qingyang 745000 China Senior engineer China Institute of Water Resources and Hydropower Research Beijing 100038 China Senior engineer Flood prevention office of YRCC Zhengzhou 450003 China

Coarse sediment retention by check dams is analyzed for five typical catchments in the Hekou-Longmen section of the midstream of the Yellow River,which is an area of high coarse sediment *** catchments are the Huangfuchuan,Kuye,Wuding,Sanchuan and Qiushui River *** amount of coarse sediment retained by check dams in these areas for different periods was *** reduction due to check dams is compared with other soil conservation measures and the results show that check dams are the most effective to rapidly reduce the amount of coarse sediment entering the Yellow *** the average percentage of the drainage area with check dams for the five typical catchments reaches 3.0%,the average sediment reduction ratio can reach 60%.Therefore,to rapidly and effectively reduce the amount of sediment,especially coarse sediment,entering the Yellow River,the area percentage of check dams in the Hekou-Longmen section should be kept around 3%.The Kuye and Huangfuchuan River Basins are the preferred main catchments in which such water conservation measures are implemented.

关键词： Sediment retention Yellow River Check dam Coarse sediment Grain size

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Weldability of 610MPa Grade High Strength Plate Steel 12MnNiVR for Oil Storage Tanks

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Journal of Iron and Steel Research International 2011年第S1期18卷 769-772页

作者： YANG Han ZHAO Wen-gui HUA Yan-ping CHEN Shao-hui ZHANG Xiao-bing QU Jin-bo Institute of Research of Iron and Steel(IRIS) Sha-steel Chief engineer office Sha-steelJiangsu215625China

The weldability of 12MnNiVR was examined in terms of the simulated HAZ continuous cooling transformation (SH-CCT) diagram,microstructure and mechanical properties of the simulated coarse grain heat-affected zone (CGHAZ).When t 8/5 is shorter,the microstructure mainly consists of lath *** t 8/5 is 60 s,the microstructure becomes coarser *** acicular ferrite appears beside lath bainite when t 8/5 =***,a microstructure composed of polygonal ferrite,acicular ferrite,and small amount pearlite is obtained with a small amount of bainite at t 8/5 >*** the increase of t 8/5,the hardness of CGHAZ decreases *** minimum impact toughness of CGHAZ appears at t 8/5 =*** hardness and the toughness of CGHAZ remain above the specified values for steel 12MnNiVR.

关键词： 12MnNiVR weldability SH-CCT coarse grain heat-affected zone

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High Efficient Blowing Technique for Large and Medium Converters

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Journal of Iron and Steel Research International 2010年第2期17卷 1-5页

作者： JIANG Xiao-fang YANG Wen-yuan WANG Ming-lin CHEN Yuan-ping GAN Yong Steelmaking Plant Baoshan Iron and Steel Co Ltd Shanghai 201900 China National engineeringResearch Center of Continuous Casting Central Iron and Steel Research Institute Beijing 100081 China general engineer office Haixin Iron and Steel Co Wenxi 043801 Shanxi China

The high efficient blowing technique includes increasing oxygen supply intensity and optimizing slag forming. The oxygen supply intensity on 300 t converters of No. 1 steelmaking shop at Baosteel reaches 3.83 m^3/（t · min）, and at Taiyuan Steel, Lianyuan Steel, Pingxiang Steel and other steel plants, the oxygen supply intensity on medium converters is in the range of 4.0--4.4m^3/（t · min）. The productivity of converter can be increased by 8% -- 15% with adopting this technique. The whole technique, including design and manufacture of lance nozzle with reasonable pacnolontenue of outlets, technique of oxygen supply and slag forming, has been developed by CISRI to meet the need of technique transfer.

关键词： converter oxygen supply intensity oxygen blowing time efficient dephosphorization

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Foster innovation and facilitate publications for zoology

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Integrative Zoology 2023年第3期18卷 397-398页

作者： Wenhua XIONG Associate Editor Integrative Zoology Senior EngineerInstitute of ZoologyChinese Academy of SciencesChina Executive DirectorOffice of the International Society of Zoological Sciences

Integrative Zoology(INZ)is the official journal of the International Society of Zoological Sciences(ISZS).The journal has made some remarkable gains in the past *** Impact Factor increases steadily and ranks top 25%in Journal Citation Reports(JCR)’s zoological journals for 7 *** journal has rallied zoologists from more than 80 *** number of submission and publication has almost doubled from 2020 to *** total downloads via Wiley Online Library increased 52.9%from 2020 to 2021,with a global *** the past year,6687 institutions offered access to our journal via Wiley license.

关键词： journal Foster doubled

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Intestinal microbiota in various animals

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Integrative Zoology 2022年第3期17卷 331-332页

作者： Wenhua XIONG Executive Editor Integrative ZoologySenior EngineerInstitute of ZoologyChinese Academy of SciencesChinaand Executive DirectorOffice of the International Society of Zoological Sciences

Research on animal intestinal microbiota is one of the most cutting-edge topics in current zoological *** addition to getting involved in host animals’physiological functions or behaviors(Aagaard et al.2014;Woting&Blaut 2016;Schretter et al.2018;Dang&Marsland 2019),the gut microbiome has been shown to influence the relation between the hosts and their neighboring species,which would eventually affect the host’s fitness and evolution positively or negatively(Douglas 2015;Sherwin et al.2019;Xu et al.2019;Groussin et al.2020;Jang&Kikuchi 2020).

关键词： eventually neighboring

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