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Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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Science China(Technological Sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2. HUANG GuanHua1,2.& QU ZhongYi3 1 Center for Agriculture water Research, China Agricultural university, Beijing 100083, China 2.Chinese-Israeli International Center for Research and Training in Agriculture, China Agricultural university, Beijing 100083, China 3 water conservancy and civil engineering college, inner mongolia Agricultural university, hohhot 010018, China 1. Center for Agriculture water Research China Agricultural University Beijing 100083 China 2. Chinese-Israeli International Center for Research and Training in Agriculture China Agricultural University Beijing 100083 China 3. water conservancy and {2. engineering college Inner Mongolia Agricultural University Hohhot 010018 China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

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Decisive influence of the ionization strength of cosmic rays on the cavitation characteristics of pure water

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Science China(Technological Sciences) 2009年第6期52卷 1804-1808页

作者： CHANG JinShi college of water {2. & civil engineering,China Agricultural university,Beijing 100083,China college of water {2. & civil engineering China Agricultural University Beijing 100083 China

The experiment result in this article shows that the initial and critical cavitation pressure of pure water are both increasing along with the increase of height above sea level,and the ionization strength of cosmic rays in the lower aerosphere is the crucial factor which influences the cavitation pressure of pure *** author concludes the relationship between the cavitaion pressure of pure water and the height above sea ***,air particles in water caused by the radiation of cosmic rays can exist in the water for a long time and will not escape.

关键词： initial cavitaiton pressure critical cavitation pressure ionization strength of cosmic rays height above sea level

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A general finite element model for numerical simulation of structure dynamics

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 440-450页

作者： WANG Fujun1, LI Yaojun1, Han K.2.& Feng Y.T.2.1. college of water {2. and civil engineering, China Agricultural university, Beijing 100083, China 2. civil & Computational engineering Centre, university of Wales Swansea, Swansea SA2.8PP, U.K. college of water {2. civil engineering China Agricultural University Beijing 100083 China civil & Computational engineering Centre University of Wales Swansea Swansea SA2 8PP UK

A finite element model used to simulate the dynamics with continuum and discontinuum is presented. This new approach is conducted by constructing the general contact model. The conventional discrete element is treated as a standard finite element with one node in this new method. The one-node element has the same features as other finite elements, such as element stress and strain. Thus, a general finite element model that is consistent with the existed finite element model is set up. This new model is simple in mathematical concept and is straightforward to be combined into the existing standard finite element code. Numerical example demonstrates that this new approach is more effective to perform the dynamic process analysis in which the interactions among a large number of discrete bodies and continuum objects are included.

关键词： finite element method, discrete element method, structure dynamics, numerical simulation.

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Thermal Conductivity and Heat Transfer Coefficient of Concrete

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Journal of Wuhan university of Technology(Materials Science) 2011年第4期26卷 791-796页

作者：郭利霞 North China university of water Resources and Electric Power

A very simple model for predicting thermal conductivity based on its definiensis was presented. The thermal conductivity obtained using the model provided a good coincidence to the investigations performed by other authors. The heat transfer coefficient was determined by inverse analysis using the temperature measurements. From experimental results, it is noted that heat transfer coefficient increases with the increase of wind velocity and relative humidity, a prediction equation on heat transfer coefficient about wind velocity and relative humidity is given.

关键词： thermal conductivity heat transfer coefficient relative humidity wind velocity

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Computational theory of cavitating flows for hydraulic turbomachinery with consideration of influence of water quality

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Science China(Technological Sciences) 2010年第12期53卷 3341-3348页

作者： WANG Lei1,2.& CHANG JinShi2.1 Huadian Electric Power Research Institute, Hangzhou 310030, China 2.college of water {2. and civil engineering, China Agricultural university, Beijing 100083, China 1. Huadian Electric Power Research Institute Hangzhou 310030 China2. College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 China

Previously it was assumed that the pressure within the cavity or on the cavity surface remained constant and the vapor pressure of clean water at 2.°C and 0 m altitude was utilized as the computational boundary for cavitating flows in hydraulic turbomachinery. Cavitation was confused with vaporization, and the effect of water quality on cavitation pressure characteristics was not taken into account. In recent years, lots of experiments of cavitation pressure characteristics of different water qualities including different sand concentrations of sand water and different altitudes of clean water have been performed by the authors, and the important influences of water quality on cavitation pressure characteristic have been validated. Thus the water quality should be involved in the cavitating flows computation. In the present paper, the effect of water quality on the cavitation pressure characteristic is analyzed and the computational method and theory of cavitating flows for hydraulic turbomachinery that considers the influence of water quality are proposed. The theory is suitable for both the potential flow method and the two-phase flow method for cavitating flows simulation. Finally, the validation results for cavitating flows in a hydraulic tur- bine indicate the significant influences of water quality on the cavitating flow performance.

关键词： cavitating flows cavitation pressure water quality hydraulic turbomachinery

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Allocation of power generating and shipping of Hanjiang upstream cascade

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Progress in Natural Science:Materials International 2005年第8期15卷 733-741页

作者： LIU Junping1* and CHANG Mingqi 2.3(1. School of civil engineering and Architecture, Zhejiang {2. of Technology, Hangzhou 310014, China 2. Institute of water Resources & Hydroelectric engineering, Xi'an {2. of Technology, Xi'an 710048, China 3. Shanxi Institute of water Resources, Taiyuan 030001, China) School of civil engineering and Architecture Zhejiang University of Technology Hangzhou 310014 China Institute of water Resources and Hydroelectric engineering Xi'an University of Technology Xi'an 710048 China Shanxi Institute of water Resources Taiyuan 030001 China

The optimal model and simulating model of the Hanjiang cascade reservoirs operation with one day as its calculating period are established to coordinate the contradictions between power generating and shipping. The optimal model is solved by progressive optimality algorithm method adopting the theory of large system decomposing and coordinating. By analyzing the water allocation results obtained from six schemes, which are two cascades, four cascades and seven cascades joint operation considering shipping or not, the contradiction degree between power generating and shipping is investigated and some joint operation schemes are proposed.

关键词： cascade power generating contradiction shipping optimal operation.

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THE ALGORITHMS AND APPLICATIONS FOR DETERMINING PERMEABILITY COEFFICIENTS BY PULSE SPECTRUM TECHNIQUE

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Journal of Hydrodynamics 2002年第2期14卷 112-115页

作者： Wang Ling-ling college of water {2. and Hydropower engineering, Hohai university, Nanjing 2.0098, China college of water {2. and Hydropower engineering Hohai University Nanjing 210098 China

The determination of inhomogeneous permeability coefficient was studied as a parameter-control inverse problem for parabolic-type equation in this paper. By virtue of PST, the solution of the inverse problem is converted into an iteration procedure of solving a direct problem and solving a Fredholm integral equation of the first kind. Besides, Tikhonov normalization method is introduced to treat the uncertainty caused by the integral equation. Thus an algorithm for determining inhomogeneous permeability coefficient has been formulated and implemented. Numerical results show: (1) The algorithm presented in the paper is suitable to strongly inhomogeneous seepagel; (2. The additional information needed for solution is merely the seepage velocity on partical boundary, so that drill works can be reduced remarkably; (3) The algorithm is applicable to determining inhomogeneous transmission coefficients in groundwater engineering or other engineering.

关键词： inverse problem Pulse Spectrum Technique (PST) permeability coefficient parameter identification

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Hybrid method of limit equilibrium and finite element internal force for analysis of arch dam stability against sliding

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Science China(Technological Sciences) 2011年第4期54卷 793-798页

作者： BAO TengFei1,2.3,XU BaoSong1,2.3 & ZHENG XueQing1,2.3 1State Key Laboratory of Hydrology-water Resources and Hydraulic engineering,Hohai {2.,Nanjing 2.0098,China 2.ational engineering Research Center of water Resources Efficient Utilization and engineering Safety,Nanjing 2.0098,China 3{6. of water conservancy and Hydropower engineering,Hohai {2.,Nanjing 2.0098,China 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 Nanjing 210098 China3. College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

A hybrid method of limit equilibrium and finite element internal force for analysis of arch dam stability against sliding is *** finite element internal force method(FEIFM) is used to provide more accurate thrust forces acting on the faces of a slip body,and the limit equilibrium method(LEM) is employed to evaluate the factor of safety of the slip *** method presented can deal with a slip body with large amount of geometrically complex slip *** addition,compared with the traditional LEM,it can meet the balance condition of the forces in the slip *** example shows that the factor of safety obtained by the method presented agrees well with the theoretical solution.A practical example is also presented to demonstrate the application of the method in the stability analysis of an arch dam *** results from the examples show that the method is promising in analysis of arch dam stability against sliding.

关键词： arch dam stability against sliding limit equilibrium method finite element internal force method

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Research on stability of the accumulated rock-soil body of reservoir bank under rainfall condition

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Science China(Technological Sciences) 2009年第9期52卷 2528-2535页

作者： GU ChongShi1,2.WU HaiZhen1,2.& SU HuaiZhi1,2.1 college of water Resources and Hydropower {2.,Hohai university,Nanjing 2.0098,China 2.National {2. Research Center of water Resources Efficient Utilization and {2. Safety,Hohai university,Nanjing 2.0098,China 3 Jiangxi water conservancy Research Institute,Nanchang 33002.,China 1. college of water Resources and Hydropower {2. Hohai University Nanjing 210098 China 2. National engineering Research Center of water Resources Efficient Utilization and engineering Safety Hohai University Nanjing 210098 China 3. Jiangxi water conservancy Research Institute Nanchang 330029 China

The shear strength parameters property of rock-soil aggregates in embankment slope of reservoir,that is,the relationship between cohesion and gravel content,between friction angle and gravel content,and the relationship between cohesion and water content,between friction angle and water content,is studied based on the direct shear test results,the shear strength change law of the rock-soil aggregates is given,and the unsaturated shear strength formulation of rock-soil aggregates that could consider suction and saturation degree influence is put forward in this paper,through which the sliding or failure physical mechanism of this type of slope under the condition of rainfall infiltration is studied. Also the 3D unsteady saturated-unsaturated seepage field and its FEM resolving mode are established based on the analysis of the slope rainfall infiltration process. Case study with this method indicates that the minimum safety factor of the accumulated rock-soil aggregates dose not arrive at the moment of rainfall cessation,but appears several hours after the rainfall cessation,this phenomenon is in accordance with the practical slope {2.'s failure process and could explain appropriately the slope failure caused by rainfall infiltration. Research results in this paper have an important reference value for the research on stability of the accumulated rock-soil aggregates in embankment slope of reservoir,and can enrich the stability analysis method and relevant theory of reservoir embankment slope.

关键词： reservoir bank slope rock-soil aggregates rainfall infiltration saturated/unsaturated seepage

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Expansive Behaviors of Self-stressing Concrete under Different Restraining Conditions

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Journal of Wuhan university of Technology(Materials Science) 2011年第4期26卷 780-785页

作者：常旭 college of civil {2. Henan Polytechnic University

The expansive behaviors of the expensive concrete under different restraining conditions were systemically studied. The experimental results indicate that expansive deformation obviously increases before 10 days and tends to be constant after 2. days regardless of the restraining conditions. The mixture ratio of expansive cement and restraining conditions are the main factors affecting expansive deformation. Self-stress can be obtained when the expansive deformation is restrained. The higher self-stress could be obtained when the expensive concrete is restrained by steel tube. For specimens under steel tube restraining, the wall thickness and the length of the steel tube have important influence on self-stress. Both the radial self-stress and axial self-stress in concrete core increase when wall thickness or length of the steel tube increases.

关键词： self-stress expansive concrete restraining condition

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