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An ecological hydraulic radius approach to estimate the instream ecological water requirement

Progress in Natural Science:Materials International 2007年第3期17卷 320-327页

作者： LIU Changming and MEN Baohui ( Key Laboratory of water Cycle and Related Land Surface Process, institute of Geographical Sciences and Natural resources research, Chinese Academy of Sciences, Beijing 100101, china Key Laboratory of water and Sediment Sciences, Ministry of Education & water Sciences College, Beijing Normal University, Beijing 100875, china Department of Hydraulic and hydropower Engineering, North china Electric Power University, Beijing 102206, china) Key Laboratory of water Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Key Laboratory of water and Sediment Sciences Beijing Normal University Beijing 100875 China Department of Hydraulic and hydropower Engineering North China Electric Power University Beijing 102206 China

This essay defines the concepts of ecological flow velocity as well as ecological hydraulic radius (EHR) and proposes an ecological hydraulic radius approach (EHRA) which considers both the watercourse information (including hydraulic radius, roughness coefficient and hydraulic gradient) and the required stream velocity necessary for maintenance of certain ecological functions all together. The key parameter of EHRA is to fix the watercourse cross-sectional flow area corresponding to EHR, by which the relation between parabola shaped cross-sectional flow area and hydraulic radius is deduced. The EHRA not only meets the requirement of flow velocity for adequate fish spawning migration, but also is applicable to the ecological flows in regard with other ecological issues (such as the calculation of the instream flow requirements for transporting sediment and for pollution self-purification, etc.). This essay has illuminated the computational process taking the estimation of ecological water requirement of Zhuba Hydrologyical Station watercourse in Niqu branch of the Yalong River as an example. Additionally, we compare EHRA with Tennant approach. The result shows that the Zhuba Hydrological Station ecological water requirement calculated by EHRA lies between the minimum and favorable ecological water requirement calculated by the Tennant approach. This is due to the fact that the ecological flow velocity (such as the fish spawning migration flow velocity) was taken into consideration, producing results applicable to the practical situation.

关键词： ecological flow flow velocity cross-sectional flow area ecological hydraulic radius (HER) instreamecological water requirement.

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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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NUMERICAL SIMULATION OF HORIZONTAL BUOYANT WALL JET

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Journal of Hydrodynamics 2010年第1期22卷 58-65页

作者： HUAI Wen-xin LI Zhi-wei QIAN Zhong-dong ZENG Yu-hong HAN Jie PENG Wen-qi State Key Laboratory of water resources and hydropower Engineering Science Wuhan University Wuhan 430072 China Department of water Environment China Institute of Water Resources and Hydropower Research Beijing100038 China

This article applies the realizable k - ω model to simulate the buoyant wall jet and gives the results of cling length, centerline trajectory and temperature dilutions at certain sections. The comparison between the numerical results and Sharp＇s experimental data indicates that the model is effective in estimating velocity distribution and temperature dilutions. The velocity profiles at the cental plane and z-plane both show a strong similarity at certain distance from the nozzle, and the distributions of velocity and temperature dilutions also exhibit a similarity along the axial direction at centerline in the near-field. Based on the results, the article gives the corresponding relationships between the distance and the dilutions of velocity and temperature, which is useful in predicting the behavior of the wall buoyant jet.

关键词： buoyancy wall jet cling length velocity profile temperature dilution

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Strategies for managing reservoir sedimentation

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International Journal of Sediment research 2009年第4期24卷 369-384页

作者： Zhao-yin WANG 1 and Chunhong HU 21 Prof., State Key Lab of Hydroscience and Engineering, Tsinghua University, Beijing 100084, china. 2 Prof., Secretary General of International research and Training Center on Erosion and Sedimentation, Beijing 100048, china and Vice President of china institute of water resources and hydropower research, No. A-1, Fuxing Rd, Beijing 100038, china. Prof. State Key Lab of Hydroscience and Engineering Tsinghua University Beijing 100084 China Prof. Secretary General of International Research and Training Center on Erosion and Sedimentation Beijing 100048 China and Vice President of China Institute of Water Resources and Hydropower Research No. A-1 Fuxing Rd Beijing 100038 China

Sediment deposition in reservoirs has caused the loss of 66% of the reservoir capacity in china. The main sedimentation control strategies are: 1) storing the clear water and releasing the turbid water; 2) releasing turbidity currents; 3) Draw-down flushing and empty flushing; and 4) dredging. The paper summarizes these strategies with examples. Sediment transport in many Chinese rivers occurs mostly during the 2-4 month flood season, that is, 80-90% of the annual sediment load is transported with 50-60% of the annual runoff. By storing the clear water after the flood season and releasing the turbid water during the flood season, less sediment deposits in the reservoir while the reservoir is still able to store enough water for power generation in the low flow season. The Three Gorges and Sanmenxia reservoirs apply this strategy and control sedimentation effectively. Turbidity currents have become the main sedimentation control strategy for the Xiaolangdi Reservoir. Empty flushing involves reservoir draw-down to temporarily establish riverine flow along the impound reach, flushing the eroded sediment through the outlets. Case studies with the Hengshan Reservoir and Zhuwo Reservoir are presented. Jet dredgers have been used to agitate the reservoir deposit so that the deposit is released from the reservoir with currents. The sediment releasing efficiency is 30-100% for storing the clear and releasing the turbid; 6-40 % for turbidity current; and 2,400-5,500% for empty flushing. Empty flushing causes high ecological stress on the ecosystem to the downstream reaches. Storing the clear and releasing the turbid is the best strategy to control reservoir sedimentation while achieving hydro-power benefit and maintain ecological stability.

关键词： Reservoir sedimentation Storing clear and releasing turbid Flushing Turbidity current Three Gorges Reservoir

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Analysis of crack propagation in concrete structures with structural information entropy

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Science china(Technological Sciences) 2010年第7期53卷 1943-1948页

作者： BAO TengFei1’2, PENG Yan1’2, CONG PeiJiang1’2 & WANG JiaLin1’2 1 State Key Laboratory of Hydrology-water resources and Hydraulic Engineering, Hohai University, Nanjing 210024, china 2 National Engineering research Center ofwater resources Efficient Utilization and Engineering Safety, Hohai University, Nanjing 210024, china State Key Laboratory of Hydrology-water resources and Hydraulic Engineering Hohai University Nanjing China National Engineering research Center of water resources Efficient Utilization and Engineering Safety Hohai University Nanjing China

The propagation of cracks in concrete structures causes energy dissipation and release, and also causes energy redistribution in the structures. Entropy can characterize the energy redistribution. To investigate the relation between the propagation of cracks and the entropy in concrete structures, cracked concrete structures are treated as dissipative structures. Structural information entropy is defined for concrete structures. A compact tension test is conducted. Meanwhile, numerical simulations are also carried out. Both the test and numerical simulation results show that the structural information entropy in the structures can characterize the propagation of cracks in concrete structures.

关键词： crack entropy concrete sun

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A NON-UNIFORM SEDIMENT TRANSPORT MODEL WITH THE BOUNDARY-FITTING ORTHOGONAL COORDINATE SYSTEM

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Journal of Hydrodynamics 2002年第1期14卷 64-68页

作者： Lu Yong-jun (River and Harbor Department, Nanjing Hydraulic research institute , Nanjing 210024, china) Chen Guo-xiang (College water resources and Environment, Hohai University, Nanjing 210024, china) River and Harbor Dept. Nanjing Hydraulic Res. Inst. Nanjing 210024 China

A 2-D non-uniform sediment mat hmatical model in the boundary-fitting orthogonal coordinate system was develop ed in this paper. The governing equations, the numerical scheme, the boundary con ditions, the movable boundary technique and the numerical solutions were present ed. The model was verified by the data of the reach 25km upstream the Jialingjia ng estuary and the 44km long main stream of the Chongqing reach of the Yangtze r iver. The calculated results show that, the water elevation, the velocity distri bution and the river bed deformation are in agreement with the measured data.

关键词： mathematical model non-uniform sus pended load non-uniform bedload boundary-fitting orthogonal coordinate system

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water Security Problem in North china: research and Perspective

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Pedosphere 2005年第5期15卷 563-575页

作者： XIA Jun LIU Meng-Yu JIA Shao-Feng Key Laboratory of water Cycle ＆Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） State Key Laboratory of water resources ＆ hydropower Engineering Sciences Wuhan University Wuhan 430072（China） Center for Agricultural resources research Institute of Genetic and Developmental Biology Chinese Academy of Sciences Shijiazhuang 050021 （China）

This paper addresses the emergence of water security problems in North china with the aim of highlighting key waterresources management and water security issues for the long-term development of North china. Three key problemsrelated to water resources and security issues in North china in the 21st century are addressed, namely 1) the watercycle under environmental change, 2) agricultural water saving, and 3) water security. Development of internationalresearch related to these issues is also reviewed. The research plan developed recently by the Chinese Academy of Sciences(CAS) is discussed and suggestions on research and development of water resources science in North china are *** to focus on experimental catchments and dedicated research stations, a detailed knowledge of the water cycle onNorth china farmland has been compiled. A range of techniques that include isotope tracers has been used to acquirehydrologic data. Much research has been devoted to developing distributed hydrological models at different scales. In thewell irrigation district, five different water saving irrigation regimes have been investigated, and these regimes have hadwidespread application, and reduced water use 60-150 mm while they increased water use efficiency (WUE) by 20%-30%.Furthermore, preventing water pollution is the most essential step to ensure North china’s water security.

关键词： environmental change North china water cycle water resources water security

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Simulating the impacts of climate variation and land-cover changes on basin hydrology: A case study of the Suomo basin

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Science china Earth Sciences 2005年第9期48卷 1501-1509页

作者： CHEN Junfeng1,2, LI Xiubin2 & ZHANG Ming2 1. institute of Remote Sensing & GIS, Peking University, Beijing 100871, china 2. institute of Geographical Sciences and Natural resources research, Chinese Academy of Sciences, Beijing 100101, china institute of Remote Sensing & GIS Peking University Beijing China institute of Geographical Sciences and Natural resources research Chinese Academy of Sciences Beijing Chin

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1970, 1986 and 1999 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%―80%, while that of land cover changes only 20%.

关键词： climate variation, land-cover changes, Suomo Basin, CHARM model, SWAT model.

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Effect of Modeling Range on Structural Analysis for Powerhouse of Hydroelectric Power Plant by FEM

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Transactions of Tianjin University 2009年第5期15卷 388-392页

作者：张启灵伍鹤皋杨华全 State Key Laboratory of water resources and hydropower Engineering Science Wuhan University Changjiang River Scientific research institute Changjiang Water Resources Commission

In this paper,three different modeling ranges were selected in the structural analysis for a hydropower *** analysis was carried out using ABAQUS *** modeling range has a remarkable effect on finite element method(FEM) calculation result at the middle position of typical cross-sections where the concrete is relatively thin,and at the region close to turbine *** the ventilation barrel,floor slabs and columns above turbine floor are excluded from FEM model,the maximum rise difference of pedestal structure increases by about 24% compared with that of the whole *** is indicated that different modeling ranges indeed affect FEM calculation result,and the structure above turbine floor in the FEM model should be included.

关键词： hydraulic structures hydroelectric power plants powerhouse modeling range FEM structural analysis

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Cosmogenic ^(21)Ne concentrations and exposure ages of summit bedrocks in the Grove Mountains,Antarctica

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Science china Earth Sciences 2010年第4期53卷 518-521页

作者： KONG Ping1,2,DING Lin2,LAI QingZhou2 & HUANG FeiXin3 1 Key Laboratory of the Earth’s Deep Interior,institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,china 2 Key Laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau research,Chinese Academy of Sciences,Beijing 100085,china 3 institute of Mineral resources research,china Metallurgical Geology Bureau,Beijing 100025,china Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China institute of Mineral resources research China Metallurgical Geology Bureau Beijing China

Various sources of 21Ne and 22Ne exist in surface rocks:cosmogenic,in situ nucleogenic from internal U and Th,trapped crustal nucleogenic and trapped *** paper reports the first measurement,in china,of cosmogenic 21Ne and 22Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 21Ne and ***-heating experiments show that concen-trations of cosmogenic 21Ne and 22Ne in summit bedrock samples R9202 and R9203 from Grove Mountains,Antarctica,are(3.83±0.87)×108 and(5.22±0.51)×108 atoms/g,*** corresponding minimum exposure ages are 2.2±0.5 and 3.0±0.3 *** indicates that the ice sheet in East Antarctica was uncovered the crest of Mount Harding,a typical nunatak in Grove Mountains,since at least mid-Pliocene.

关键词： 21Ne cosmogenic nuclide exposure age Antarctica Grove Mountains

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