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Journal of Hydrodynamics 2016年第3期28卷 489-496页

作者：刘士和薛娇 School of water resources and hydropower engineering Wuhan University

The mechanical energy loss and the wall resistance are very important in practical engineering. These problems are investigated through theoretical analysis and numerical simulation in this paper, The results are as follows. （1） A new mechanical energy equation for the total flow is obtained, and a general formula for the calculation of the mechanical energy loss is proposed. （2） The general relationship between the wall resistance and the mechanical energy loss for the steady channel flow is obtained, the simplified form of which for the steady uniform channel flow is in consistent with the formula used in Hydraulics deduced by 7r theorem and dimensional analysis. （3） The steady channel flow over a backward facing step with a small expansion ratio is numerica- lly simulated, and the mechanical energy loss, the wall resistance as well as the relationship between the wall resistance and the mechanical energy loss are calculated and analyzed.

关键词： channel flow energy equation mechanical energy loss resistance

Along-track Calibration of the Zhurong Rover Magnetometer

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Science China Earth Sciences 2024年第2期67卷 552-565页

作者： Hao LUO Aimin DU Yasong GE Ying ZHANG Haiying LI Lin TIAN Kuixiang ZHANG Shuquan SUN Lin ZHAO Zhi LI Xiao FENG CAS engineering Laboratory for Deep resources Equipment and Technology Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China College of Earth Science University of Chinese Academy of SciencesBeijing100049China National Astronomical Observatories Chinese Academy of SciencesBeijing100101China

As part of the Chinese Tianwen-1 mission,the Zhurong Rover began its scientific investigation in the southern Utopia Planitia after its successful landing in 15 May,*** Zhurong Rover magnetometer(RoMAG),one of the six payloads onboard the rover,includes two identical high-sensitivity triaxial fluxgate magnetometers and can implement mobile magnetic measurements on the surface of *** a rover magnetic compensation procedure was conducted to remove the magnetic interferences pre-launch,due to the different state of the payloads and electric power system such as the solar panel,an along-track calibration of the magnetometer is necessary to obtain a more accurate Martian magnetic *** methods,mast yaw rotations and Rover yaw rotations were utilized separately to determine the Martian horizontal magnetic *** show that the Martian horizontal magnetic components determined by the two methods are in good agreement,with the root mean square deviation less than 2.0 *** vertical component was also constrained through the pitch movements of the mast by assuming the interferences field distributes like a dipole field.A linear correlation between magnetic field measurements and the solar array currents was derived to calibrate the body field during the regular *** conclude that more accurate measurements could be made when applying the calibration results in the magnetic survey on the surface of Mars.

关键词： The Zhurong Rover Magnetometer Along-track calibration Remnant magnetization

The effects of various factors on spontaneous imbibition in tight oil reservoirs

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Petroleum Science 2024年第1期21卷 315-326页

作者： Cheng Liu Tian-Ru Wang Qing You Yue-Chun Du Guang Zhao Cai-Li Dai School of Energy resources China University of GeosciencesBeijing100083PR China School of Petroleum engineering China University of PetroleumQingdao266580ShandongPR China

Slickwater fracturing fluids have gained widespread application in the development of tight oil reservoirs. After the fracturing process, the active components present in slickwater can directly induce spontaneous imbibition within the reservoir. Several variables influence the eventual recovery rate within this procedure, including slickwater composition, formation temperature, degree of reservoir fracture development, and the reservoir characteristics. Nonetheless, the underlying mechanisms governing these influences remain relatively understudied. In this investigation, using the Chang-7 block of the Changqing Oilfield as the study site, we employ EM-30 slickwater fracturing fluid to explore the effects of the drag-reducing agent concentration, imbibition temperature, core permeability, and core fracture development on spontaneous imbibition. An elevated drag-reducing agent concentration is observed to diminish the degree of medium and small pore utilization. Furthermore, higher temperatures and an augmented permeability enhance the fluid flow properties, thereby contributing to an increased utilization rate across all pore sizes. Reduced fracture development results in a lower fluid utilization across diverse pore types. This study deepens our understanding of the pivotal factors affecting spontaneous imbibition in tight reservoirs following fracturing. The findings act as theoretical, technical, and scientific foundations for optimizing fracturing strategies in tight oil reservoir transformations.

关键词： Tight oil reservoir Spontaneous imbibition Nuclear magnetic resonance Slickwater fracturing fluid Fluid utilization degree

Evaluation of Rainfall Tendency for the Twentieth Century over Indira Sagar Region in Central India

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American Journal of Climate Change 2024年第1期13卷 47-68页

作者： Rituraj Shukla Deepak Khare Ramesh P. Rudra Priti Tiwari Himanshu Sharma Prasad Daggupati Pradeep Goel School of engineering University of Guelph Guelph Canada Department of water resources Development and Management Indian Institute of Technology Roorkee India Indira Gandhi Agricultural University Raipur India Department of Civil engineering Institute of Infrastructure Technology Research and Management (IITRAM) Ahmedabad India

The study investigates long-term changes in annual and seasonal rainfall patterns in the Indira Sagar Region of Madhya Pradesh, India, from 1901 to 2010. Agriculture sustainability, food supply, natural resource development, and hydropower system reliability in the region rely heavily on monsoon rainfall. Monthly rainfall data from three stations (East Nimar, Barwani, and West Nimar) were analyzed. Initially, the pre-whitening method was applied to eliminate serial correlation effects from the rainfall data series. Subsequently, statistical trends in annual and seasonal rainfall were assessed using both parametric (student-t test) and non-parametric tests [Mann-Kendall, Sen’s slope estimator, and Cumulative Sum (CUSUM)]. The magnitude of the rainfall trend was determined using Theil-Sen’s slope estimator. Spatial analysis of the Mann-Kendall test on an annual basis revealed a statistically insignificant decreasing trend for Barwani and East Nimar and an increasing trend for West Nimar. On a seasonal basis, the monsoon season contributes a significant percentage (88.33%) to the total annual rainfall. The CUSUM test results indicated a shift change detection in annual rainfall data for Barwani in 1997, while shifts were observed in West and East Nimar stations in 1929. These findings offer valuable insights into regional rainfall behavior, aiding in the planning and management of water resources and ecological systems.

关键词： Precipitation Parametric Non-Parametric Tests Trend Analysis Serial Correlations

Basin flood control system risk evaluation based on variable sets

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Science China(Technological Sciences) 2017年第1期60卷 153-165页

作者： PENG Yong CHU JingGang XUE ZhiChun Department of water resources China Institute of Water Resources and Hydropower Research Beijing 100038 China

Flood control system risk evaluation is an effective measure for flood risk management and *** order to make better flood risk decisions and thereby improve social and economic benefits,the flood control risk evaluation index system should be built to quantify and normalize flood risk effectively and *** the current evaluation index has the binary miscibility characteristic of fuzziness and clarity,this paper establishes a new flood control system risk evaluation method based on the theory of variable sets(VS).Through a comparison of flood control risk evaluation with variable fuzzy sets(VFS) in the same basin flood control system risk evaluation,it is revealed that the new method,i.e.,flood control risk evaluation with variable fuzzy/clear mixture sets(variable sets),will be reasonable in all ***,in one case study,i.e.,the flood control system risk evaluation of Fengman Reservoir Basin,which is located in the southeast central of Jilin Province in China,the risk evaluation levels for each county in the basin as well as the whole flood risk distribution map of the basin could be provided with the new *** provides useful information for basin flood control planning and design.

关键词： variable sets (VS) flood control system risk evaluation evaluation indices flood control risk distribution map

Spatial variability of irrigation factors and their relationships with “corridor-barrier” functions in the Longitudinal Range-Gorge Region

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Chinese Science Bulletin 2007年第A02期52卷 33-41页

作者： GU ShiXiang HE DaMing CUI YuanLai XIE XianHong LI YuanHua State Key Laboratory of water resources and hydropower engineering Science Wuhan University Wuhan 430072 China yunnan institute for investigation Design and Research of Water Resources & Hydropower Engineering Kunming 650021 China Asian International Rivers Center Yunnan University Kunming 650091 China Department of Irrigation Drainage and Rural Water Supply Ministry of Water Resources P. R. China Beijing 100053 China

在纵的范围峡区域( LRGR )和包围区域从 1971～2000 在 58 个气象学的车站基于每月气象学的数据，包括每年的 et 0 的六个因素，最大的每月的 et 0 (5月)，最小的每月的 et 0 (12月)，稻灌溉限额和全部的农业灌溉限额(到6月的从4月... 详细信息

在纵的范围峡区域( LRGR )和包围区域从 1971～2000 在 58 个气象学的车站基于每月气象学的数据，包括每年的 et 0 的六个因素，最大的每月的 et 0 (5月)，最小的每月的 et 0 (12月)，稻灌溉限额和全部的农业灌溉限额(到6月的从4月的每年、主要的灌溉时期)被选择用一条 geostatistical 途径检验他们的空间可变性。结果显示 Morans 的系数我，描述空间自相关的紧张，比在另外的方向在纵的方向是更大的；六个参数的空间可变性被结构的因素财务主要为 60.2%87.9% 引起；et 0 的最大的可变性(每年，在 5 月和 12 月) 出现在西北东南和东北西南方向。由于夏天季风从印度洋和太平洋的大气的环流，和大陆人在冬季，最小的分数维的尺寸和 et 0 的最大的空间可变性的温暖干燥的电流(每年，在 5 月和 12 月) 发生在西南东北和东南西北方向。稻和全部的农业灌溉要求的最高的可变性由于纵的河的走廊功能引起的蒸汽和精力散开发生在南方北方方向。最小的空间自相关在东方西方方向，它证明农业灌溉要求的六个参数被走廊障碍功能在 LRGR 和它的包围区域影响。

关键词：空间可变性灌溉影响因素纵向岭谷区

Development status and prospect of underground thermal energy storage technology

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Journal of Groundwater Science and engineering 2024年第1期12卷 92-108页

作者： Ying-nan Zhang Yan-guang Liu Kai Bian Guo-qiang Zhou Xin Wang Mei-hua Wei School of Earth science and engineering Hebei University of EngineeringHandan 056038Hebei ProvinceChina institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Technology Innovation Center of Geothermal&Hot Dry Rock Exploration and Development Ministry of Natural ResourcesShijiazhuang 050061China Shanxi Key Laboratory for Exploration and Exploitation of Geothermal resources Taiyuan 030024China Shanxi Geological engineering Exploration institute Taiyuan 030024China

Underground Thermal Energy Storage(UTES)store unstable and non-continuous energy underground,releasing stable heat energy on *** effectively improve energy utilization and optimize energy *** UTES technology advances,accommodating greater depth,higher temperature and multi-energy complementarity,new research challenges *** paper comprehensively provides a systematic summary of the current research status of *** categorized different types of UTES systems,analyzes the applicability of key technologies of UTES,and evaluate their economic and environmental ***,this paper identifies existing issues with UTES,such as injection blockage,wellbore scaling and corrosion,seepage and heat transfer in cracks,*** suggests deepening the research on blockage formation mechanism and plugging prevention technology,improving the study of anticorrosive materials and water treatment technology,and enhancing the investigation of reservoir fracture network characterization technology and seepage heat *** recommendations serve as valuable references for promoting the high-quality development of UTES.

关键词： Aquifer thermal energy storage Borehole thermal energy storage Cavern thermal energy storage Thermal energy storage technology Benefit evaluation

Impact of the Yalong-Yellow River water transfer project on the eco-environment in Yalong River basin

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Science China(Technological Sciences) 2013年第4期56卷 831-842页

作者： WANG LingHe YAN DengHua WANG Hao YIN Jun BAI YinBaoLiGao School of Hydraulic engineering Dalian University of Technology Department of water resources China Institute of Water Resources and Hydropower Research State Key Laboratory of Simulation and Regulation of water Cycle in River Basin China Institute of Water Resources and Hydropower Research Department of Hydraulic Research China Institute of Water Resources and Hydropower Research

The planning Yalong-River water transfer project will transfer 5.65 billion cubic meters water from the Yalong River into the Yellow River per *** Yalong River will be dramatically impacted hydrologically and ecologically because more than 60% of the runoff will be *** ecohydrological model was used to evaluate the impacts of the project on river corridor and wetland in this *** is a typical plateau river species and was used as the indicator species for assessment of the impact of water transfer *** model simulated the habitat area of Schizothorax in the reach between the Reba Dam and the Ganzi Hydrology Station on the Yalong *** Reba Dam,A'an Dam and Renda Dam will be constructed in the Yalong River for enhancing the water level for water diversion into the Yellow *** velocity,channel width,runoff,and water depth will be reduced due to the water transfer,especially during flood *** reduction in the velocity,channel width,runoff and water depth will occur mainly in the reach near the three dams and the reduction will be reduced to a minimum level in a distance about 100 km downstream of the *** maximum net water loss of Kasha Lake is only 1197200 m3,only 0.3% of runoff flowing into the *** project cannot bring adverse effect on the *** habitat area of Schizothorax in the Yalong River might be reduced if the water was transferred from the Reba *** habitat area of this species will be reduced more than 40%.

关键词： eco-environment water transfer project impact physical habitat modeling habitat area Yalong River

Hydration Mechanism of Cement-based Materials with Different Si-rich Mineral Admixtures

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Journal of Wuhan University of Technology(Materials Science) 2018年第3期33卷 654-660页

作者：何真胡玲玲 State Key Laboratory of water resources & hydropower engineering Science Wuhan University School of water resources and hydropower engineering Wuhan University

Early hydration mechanism of cement-based materials with silica fume, nano-SiO2 and silica sol of different contents was investigated, and the detailed effect of these Si-rich mineral admixtures in three stages of early hydration（NG, I, D） using kinetics model was focused. The results showed that silica fume, nano-SiO2, and silica sol have significant effect on kinetic parameters n, k1, k2 and k3, the fineness and existing form of SiO2 particles in these Si-rich mineral admixtures are two important factors to affect the hydration process and on the parameters. Through integrated use of methods of hydration heat-Krstulovic-Dabic Modelsynthetical thermal analysis, data of hydration heat were collected, hydration degree was characterized, as well as the resulting crystallization behavior of early hydration, to build a numerical relationship between parameter n and CH contents that n decreases with increasing CH, and thus, a direct connection between hydration heat release behavior and crystallization behavior has been established.

关键词： silica fume nano-SiO2 silica sol hydration kinetics model early hydration CH content

Seismic safety of high concrete dams

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Earthquake engineering and engineering Vibration 2014年第S1期13卷 1-16页

作者： Chen Houqun China institute of water resources and hydropower Research (IWHR) Professor

China is a country of high seismicity with many hydropower resources. Recently,a series of high arch dams have either been completed or are being constructed in seismic regions,of which most are concrete dams. The evaluation of seismic safety often becomes a critical problem in dam design. In this paper,a brief introduction to major progress in the research on seismic aspects of large concrete dams,conducted mainly at the institute of water resources and hydropower Research(IWHR) during the past 60 years,is presented. The dam site-specific ground motion input,improved response analysis,dynamic model test verification,field experiment investigations,dynamic behavior of dam concrete,and seismic monitoring and observation are described. Methods to prevent collapse of high concrete dams under maximum credible earthquakes are discussed.

关键词： review and prospect seismic safety high concrete dam dam-foundation-reservoir interaction damage-rupture process