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Analysis and application of the scale effect of flood discharge atomization model

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Science china(Technological Sciences) 2011年第S1期54卷 64-71页

作者： WU ShiQiang 1,WU XiuFeng 1,2,ZHOU Hui 1,CHEN HuiLing 1,SHA HaiFei 1 & ZHOU Jie 1 1 State Key Laboratory of hydrology-Water resources and Hydraulic Engineering,nanjing Hydraulic research institute,nanjing 210029,china 2 hohai university,nanjing 210098,china 1. State Key Laboratory of hydrology-Water resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210029 China 2. hohai university Nanjing 210098 China

The phenomenon of discharge atomization occurs as hydraulic structures discharging,which influences the safety of power station,electrical equipment and produces environmental pollution.A series of physical model tests and feedback analysis are adapted to preliminarily study the scale effect of discharge atomization model by use of the field observation data of discharge *** effect of Re and We numbers of flow on the atomization intensity is analyzed.A conversion relationship of atomization intensity between prototype and model results and the similarity criteria of the atomization range are developed. The conclusion is that the surface tension of discharge atomization model could be ignored when the Weber number is larger than *** case studies are given by use of the similitude criteria of the atomization model.

关键词： discharge atomization scale effect energy dissipation model test feedback analysis

Back analysis of mechanical parameters of roller compacted concrete dam

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Science china(Technological Sciences) 2010年第3期53卷 848-853页

作者： GU ChongShi 1,2,3,LI Bo 1,XU GuangLei 4 &YU Hong 1,2,3 1 State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering,hohai university,nanjing 210098,china 2College of Water Conservancy Hydropower,hohai university,nanjing 210098,china 3National Engineering research Center of Water Resources Engineering Safety,Efficient Utilization and nanjing 210098,china 4 nanjing Hydraulic research institute,nanjing 210029,china 1. State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China2. College of Water Conservancy Hydropower Hohai University Nanjing 210098 China3. National Engineering Research Center of Water Resources Engineering Safety Efficient Utilization and Nanjing Nanjing 210098 China4. Nanjing Hydraulic Research Institute Nanjing 210029 China

In view of the diversity and complexity of mechanical parameters of roller compacted concrete dam(RCCD),the uniform design method,partial least-squares regression(PLS)and least squares support vector machine(LSSVM)were applied to the back analysis of RCCD with the use of the complex nonlinear relationship between dam mechanical parameters and dam *** the process of back analysis,the initial samples of parameters were designed with uniform design ***,a transversely isotropic model of RCCD was established by *** *** this model,training samples of LSSVM model could be *** then,the complex nonlinear relationship between relative values of hydraulic components of dam displacements and mechanical parameters was ***,actual relative values of dam hydraulic components are isolated from the measured data of dam displacements by using *** inputting the isolated relative values into LSSVM model,the back analysis values of RCCD mechanical parameters can be *** example analysis showed that mechanical parameters obtained by the above-mentioned back analysis method are reasonable,and the back analysis method is feasible.

关键词： roller compacted concrete dam mechanical parameters back analysis

INFLUENCE OF SEEPAGE FACE OBLIQUITY ON DISCHARGE OF GROUNDWATER AND ITS POLLUTANT INTO LAKE FROM A TYPICAL UNCONFINED AQUIFER

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Journal of Hydrodynamics 2007年第6期19卷 756-761页

作者： LI Yong WANG Chao YANG Lin-zhang LI Yi-ping State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China College of Environmental Science and Engineering Hohai University Nanjing 210098 China institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

Lab experiment and mathematical simulation Modular three dimensional finite difference groundwater （MODFLOW） were performed in a soil tank to simulate the hydrogeochemical interaction between lake and typical unconfined aquifer. Results show that the velocity decreases exponentially with the transect distance on seepage face. The maximal velocity occurs at the top point of seepage face. The obliquity of seepage face has a great influence on the maximum and distribution of seepage velocity. With the increase of the obliquity of seepage face, the maximal velocity decreases quickly and the velocity distribution becomes much more even. Most of groundwater flow and pollutant flux discharges through a narrow portion near the top of seepage face. The flow and mass concentrated in the narrow portion increase with the decrease of the obliquity of seepage face. These will benefit to design a reasonable and economical scenario to manage lakeshore and to control the pollution of lake water near lakeshore.

关键词： shallow lake unconfined aquifer groundwater discharge velocity distribution chloride MODFLOW

Application analysis of empirical mode decomposition and phase space reconstruction in dam time-varying characteristic

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Science china(Technological Sciences) 2010年第6期53卷 1711-1716页

作者： ZHANG ZhiJun1,2,3,GU ChongShi1,2,BAO TengFei1,2,ZHANG Lan1,2 & YU Hong1,2 1 State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering,hohai university,nanjing 210098,china 2 National Engineering research Center of Water Resources Efficient Utilization and Engineering Safety,hohai university,nanjing 210098,china 3 Department of Civil,Environmental and Geomatic Engineering,Swiss Federal institute of Technology,Zurich 8093,Switzerland 1. State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China2. National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210098 China3. Department of Civil Environmental and Geomatic Engineering Swiss Federal Institute of Technology Zurich 8093 Switzerland

In view of some courses of the time-varying characteristics processing in the analysis of dam deformation,the paper proposes a new method to analyze the dam time-varying characteristic based on the empirical mode decomposition and phase space reconstruction *** of all,to reduce the influences on the traditional statistical model from human factors and assure the analysis accuracy,response variables of the time-varying characteristic are obtained by the way of the empirical mode decomposition;and then,a phase plane of those variables is reconstructed to investigate their processing *** methods have already been applied to an actual project and the results showed that data interpretation with the assists of empirical mode decomposition and phase space reconstruction is effective in analyzing the perturbations of response variables,explicit in reflecting the entire development process,and valid for obtaining the evolution rules of the time-varying *** methodology is a powerful technical support for people to further master the rules of dam operation.

关键词： dam safety monitoring dam time-varying characteristic empirical mode decomposition phase space reconstruction

Total control-based unified allocation model for allowable basin water withdrawal and sewage discharge

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Science china(Technological Sciences) 2010年第5期53卷 1387-1397页

作者： HU SiYi1,2,WANG ZongZhi1,WANG YinTang1 & ZHANG LingLing3 1 State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering,nanjing Hydraulic research institute,nanjing 210029,china 2 Ministry of Water Resources,the People’s Republic of china,Beijing 100053,china 3 School of Public Administration,hohai university,nanjing 210098,china 1. State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210029 China2. Ministry of Water Resources the People’s Republic of China Beijing 100053 China3. School of Public Administration HoHai University Nanjing 210098 China

In this paper,a new model with a total amount control target of allowable water withdrawal based on initial water right is built for the implementation of initial water right allocation scheme as well as unified allocation for allowable water withdrawal and sewage *** model couples the water allocation simulation model and the computational model of permissible pol-lution bearing *** view of the model complexity,a new technology which synthesizes system simulation,iterative reservoir turns and intelligent computation is proposed to improve the operability of allocation scheme and computational *** the Beijiang River Basin in the Pearl River Basin as an example,the study explains the model establishment,solution and application,and draws an optimized operation graph of large-scale *** study also obtains a long-term operation strategy of river basin water resources system,the allocation schemes of allowable water withdrawal and sewage discharge in a typical year and the flow hydrographs of trans-boundary *** validity of the model and the allocation rationality are analyzed as well.

关键词： water resources management total control unified control of water withdrawal and sewage discharge optimized regulation integration technology

Differential Hydrological Grey Model (DHGM) with self-memory function and its application to flood forecasting

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Science china(Technological Sciences) 2009年第4期52卷 1039-1049页

作者： CHEN XiangDong1, XIA Jun1,2 & XU Qian3 1 Key Laboratory of Water Cycle and Related Land Surface Processes, institute of Geographic Sciences and Natural Resources research, Chinese Academy of Sciences, Beijing 100101, china 2 State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan university, Wuhan 430072, china 3 School of hydrology and Water Resources, hohai university, nanjing 210098, china 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 2. State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China 3. School of hydrology and Water Resources Hohai University Nanjing 210098 China

This paper addresses a problem of flood forecasting with the self-memory function. Considering flood forecasting’s uncertainty and updating demand, a hybrid hydrological model, namely Differential Hy- drological Grey Model with self-memory function (DHGM-SM), is developed. The model has two fold features. One is to establish a self-memorization equation linked with DHGM, that could extract useful information from past data series and realize updating of hydrological dynamic process. The other is that this model has higher efficiency relative to original hydrological model without self-memory func- tion. This approach was applied to river flow forecasting of two representative basins in Tunxi of South china and Daqinggou of North china. It is shown that this hybrid method has satisfactory forecasting accuracy by examination of both calibration and validation.

关键词： differential grey model the self-memorization principle real-time forecasting faded-memory recursive least square method

Temporal variation of suspended sediment load in the Pearl River due to human activities

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International Journal of Sediment research 2011年第4期26卷 487-497页

作者： Wei ZHANG,Shousheng MU,Yanjing ZHANG,and Kaimin CHEN 1 Assoc.Prof.,State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering,hohai university, nanjing,210098,china, 2,4 Graduate student,College of Harbor,Coastal and Offshore Engineering,hohai university,nanjing,210098, china 3 Prof.,china institute of Water Resources and Hydropower research,Beijing,100038,china [a] Assoc. Prof. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China [b] Graduate student College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China [c] Prof. China Institute of Water Resources and Hydropower Research Beijing 100038 China [d] Graduate student College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China

Data on sediment flux at three hydrologic stations from the 1950s to 2006 are utilized to study the decadal,annual,and monthly variations in suspended sediment load delivered from the Pearl River to the *** show that variations in sediment flux from three main tributaries,including the West River,the North River and the East River,are spatially *** nearly 90%of the suspended sediment load comes from the West River,its variation has dominated the overall tendency of sediment flux in the entire Pearl *** a significant decreasing trend exists in the annual variation of the total sediment flux,the decadal change can be divided into an increasing phase and a decreasing phase,with the turning point between the two phases in the late *** the 1950s to the 1980s,the average annual river sediment flux increased by 30.43%.However,sediment flux has decreased significantly since the 1990s,with the average sediment flux being 38.60%less in the 2000s than that in the *** current sediment flux is also 52.93%less than its peak in the 1980s. The monthly variation pattern of the suspended sediment load transport to the sea is more interesting. For the West River,all months show a decreasing trend,and for most months the reduction values are ***,for the East River the sediment load shows a decrease trend in the dry season and an increase trend in the wet *** method of regression analysis was used to study the influence of precipitation in the variation on the sediment *** was found that the climate change is not the main driving force behind the variation in suspended sediment *** the 1990s, intensive land use destroyed the vulnerable ecosystem of the upper Pearl River,and speeded up the process of rocky ***,aggravated soil erosion caused an increase in suspended sediment ***,sediment retention within reservoirs had begun to play a dominant role after the massive constru

关键词： Pearl River Sediment flux Human activities Rocky desertification Dam construction

HYDRODYNAMIC CHARACTERISTICS OF CHINESE STURGEON SPAWNING GROUND IN YANGTZE RIVER

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Journal of Hydrodynamics 2008年第2期20卷 225-230页

作者： YANG Yu YAN Zhong--min CHANG Jian-bo nanjing Hydraulic research institute Nanjing 210029 China State Key Laboratory of hydrology-Water Resources and Hydraulic Engineering Nanjing 210029 China College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China institute of Hydro-ecology Wuhan 430072 China

Since the construction of the Gezhouba Dam on the Yangtze River in 1981, it has been found that the Chinese Sturgeon, Acipensor sinensis, performs natural propagation annually in a narrow reach downstream close to the Gezhouba Dam site. This might allow one to better investigate the river hydrodynamic conditions of the Chinese Sturgeon spawning ground. In this article, spatial Kinetic Energy Gradient （KEG） and absolute value of vorticity were computed along the river sections from measured data. The relation between Spawn Density per Unit Area （SDUA） and vorticity strength and between SDUA and KEG were worked out. The Results showed that the vorticity and KEG were both effective parameters for describing the hydrodynamic characteristics of Chinese Sturgeon spawning ground. The Chinese Sturgeons prefer to spawn in the river sections where the value of vorticity strength is larger than 0.4 s^-1 and KEG is larger than 0.029 Jkg^-1m^-1.

关键词： hydrodynamic characteristics Chinese Sturgeon spawning ground vorticity kinetic energy gradient Spawn Densityper Unit Area (SDUA)

Runoff reduction due to environmental changes in the Sanchuanhe river basin

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International Journal of Sediment research 2008年第2期23卷 174-180页

Recently,runoff in many river basins in china has been ***,the role that climate change and human activities are playing in this decrease is currently of *** this study,we evaluated an assessment method that was designed to quantitatively separate the effects of climate change and human activities on runoff in river ***,we calibrated the SIMHYD rainfall runoff model using naturally recorded hydro-meteorologic data pertaining to the Sanchuanhe River basin and then determined the effects of climate change and human activities on runoff by comparing the estimated natural runoff that occurred during the period in which humans disturbed the basin to the runoff that occurred during the period prior to disturbance by *** results of this study revealed that the SIMHYD rainfall runoff model performs well for estimating monthly *** addition,we found that absolute runoff reductions have increased in response to human activities and climate change,with average reductions of 70.1% and 29.9% in total runoff being caused by human activities and climate change,*** together,the results of this study indicate that human activities are the primary cause of runoff reduction in the Sanchuanhe River basin.

关键词： Sanchuanhe River Hydrological simulation Climate change Human activities Impact