The sustainable yield of groundwater is usually referred as the maximum threshold of groundwater exploitation and utilization at regional level， and it is an important control indicator for groundwater governance and protection. With the goal of maintaining the stability of the groundwater drainage structure in the hilly area， a method for calculating the recoverable amount of groundwater in the hilly area based on the natural base-diameter ratio—base-diameter ratio relationship curve method is proposed； to ensure the water demand of the ecological environment in the river course， A method for calculating the recoverable amount of groundwater in the hilly area， which takes the degree of water resources development and utilization as the control index， is proposed—the control method of the available surface water. It takes Chifeng City as an example， the sustainable yield of ground water in hilly areas is 407 million m³. The result matches the actual situation in Chifeng City therefore proving the calculation is rational. The yield in Chifeng City can promote the acceptable exploitation and sustainable use of groundwater， and maintain ecological security in that region. It can also be taken as a research reference for calculating sustainable yield of groundwater in hilly areas in China.

To some degree， the contents of the chemical components of a region before or during a relatively low-impact period can be used as the environmental background value for a region. In this paper，four environmental zones of phreatic water are divided in Yinchuan Area on the basis of comprehensive analysis of the hydrogeological condition. The phreatic water quality results in 1987-1989 are analyzed by mathematical statistics method， and the background values of 10 components in each zones are given by using concentration value， standard deviation， coefficient of variation and range of content. The spatial distribution law and regional variability of phreatic background value are analyzed. The results show that the phreatic background value is the highest in the fluvial-lacustrine plain area， the second in floodplains and alluvial-diluvial plains， and the lowest in the diluvial inclined plains. The spatial variation characteristics of the background values of the phreatic reflect the zonal characteristics of the hydrologic geochemistry of groundwater flow， from the main role of dissolution to the balance of filter and concentration， and then to the concentration of the main role. Following the evolution law of hydrochemical components from deficit to enrichment in the discharge area from the piedmont recharge area， and river dilution is obvious in the eastern floodplains.

In view of the serious damage and degradation of the ecological environment of the Maozhou River Basin， according to the characteristics of habitat destruction and degradation of the Maozhou River， in order to improve the status quo of the Maozhou River Basin， on the basis of the research of river ecological restoration and the successful engineering practice， this paper selects four first-level indicators of hydrology， water quality， geo-morphological structure and biology. And by screening 12 secondary indicators， the construction of river classification and standard system， systematic clustering and analyzing the same characteristics of the river section， for different characteristics of different types of ecological restoration models， repair recommendations are given. The results show that the river studied is divided into 5 categories， according to actual needs and the characteristics of the classification results， the river is divided into hydrologic-water quality-geomorphology-bioremediation model， flow-water quality-geomorphology-bio-remediation model， hydrologic-water quality-bio-remediation mode and flow rate-water quality-meandering-bioremediation model. The share stake is 42%， 24%， 8% and 26% respectively. According to different ecological restoration models， restoration suggestions concerning restoring the natural hydrological and hydraulic state and create river self-repair ability are put forward.

In order to formulate the ecological water replenishment plan of northern cut-off river more scientifically，this paper takes the Beijing section of the Yongding River as the research area. Based on the established channel hydraulics model， it simulates and analyzes the ecological water replenishment process of the study area in 2019 and 2020， and quantifies the amount of evaporation and leakage loss during the ecological replenishment process accounting for about 20%. The larger the replenishment flow of Guanting Reservoir， the lower the reduction rate of the peak flow of each downstream section. In order to reduce the flow loss and improve the utilization rate of the replenishment flow， it is suggested that the replenishment flow should be between 40~80 m³/s under the condition of relatively abundant water source， and the method of alternating small flow and large flow replenishment should be adopted at the same time. Under the condition of limited water source， the alternations of high-flow and low-flow water replenishment can be considered proper to realize the optimization of ecological water replenishment benefit in the basin.

When sudden pollution accidents occur in temperature stratified reservoirs， it is of great significance to grasp the hydrodynamic and water temperature characteristics of water bodies to judge the development of pollution events and guide policy-making. MIKE3 software can be used for the three-dimensional simulation of reservoir hydrodynamics and water temperature. In order to explore further the influence of the model’s horizontal grid division and vertical coordinate system selection on the density flow， based on previous physical model experiments the numerical models of triangular， rectangular， and triangular-rectangular coupled grids are constructed. The σ coordinates and σ-Z mixed coordinates are adopted. The results show that MIKE3 software can effectively simulate the characteristics of temperature stratified density flow. It can be concluded that when the mainstream direction of density flow is very significant， it is recommended to use a rectangular grid to discretize the study area. The ladder approximation of Z-coordinate model can be effectively weakened by increasing the number of vertical stratifications. For water bodies with large differences in temperature stratifies interface， mainstream direction and the slope of riverbed， it is recommended to use σ-Z mixed coordinates in the vertical direction.

Rain gardens can effectively control the volumes and quality of rainwater runoff，but the application experience in islands is lacking.In the island area of Zhoushan， Zhejiang， the complete water balance method and indoor optimization experimental are used to design and construct a 50 m² impervious rain garden. Through real-time monitoring runoff data of 4 precipitation events， this paper evaluates the operating effects of rain gardens in island areas under different rainfall intensities.The results show that the rain garden in the island area has good retention capacity，and no overflow during the monitoring period.The total runoff reduction rate is 64.60%～89.71%，with an average of 76.64%.The flood peak reduction rate is 70.52%～91.23%，with an average of 84.76%，rainfall intensity is negatively correlated with the reduction rate of total runoff， and has little correlation with the reduction rate of flood peak.The rain garden has a good purification effect on SS，COD，NH₃-N， NO₃-N， TN， PO₄ ³⁺ and TP in runoff，and the average removal rate is 82.26%，42.17%，66.70%，64.94%，58.64%，65.24% and 76.46%，respectively.The research can provides a reference for the design and application of rain gardens in island areas.

In order to improve the management efficiency of the river chief system and meet the needs of the monitoring and management for water eco-environment restoration， based on an in-depth research on the requirements for the application and management of the river chief system and the concerns of the water eco-environment restoration， the framework of monitoring and management platform for water eco-environment restoration of the river chief system in China is proposed. The platform is based on data， takes the process as the core， and takes financial risk control as the goal to achieve the whole life cycle management of water environment treatment and ecological restoration， real-time and quantitative management of eco-environment responsibility， forecasting and management of eco-environment risks， and management of budget and final accounts of eco-environment finance， so as to formulate the best comprehensive repair plan. The application of the platform provides a scientific and effective support for improving the monitoring and management capabilities of water eco-environment restoration of the river chief in China， and reduces the technical and commercial risks of water eco-environment restoration.

In this paper， based on the monitoring data of mineral water chemistry in Changbai Mountain Area， geostatistics and hydrochemical analysis method are used to study the chemical characteristics and causes of mineral water， and the evaluation index system of water quality health function is established. The results show that： the mineral water in the study area is mainly composed of single metasilicic type and CO₂ compound metasilicic type. The TDS， total alkalinity， total hardness and CO₂ content of the composite mineral spring are 1~2 orders of magnitude higher than that of the single type mineral spring. The metasilicic content has different spatial distribution characteristics compared with other components. Weathering of rocks is the main reason for the formation of metasilicic mineral water and the main reason for the formation of the composite mineral spring is that the deep hot water rises along the fracture and mixes with the shallow groundwater. Weak alkaline and low hardness metasilicic type mineral spring is widely distributed in the region. The content of each index meets the quality standard of mineral water and tastes good.

In order to study the purification effect of construction waste recycled aggregates used in permeable pavement on runoff water quality， the surface layer and internal structure of permeable concrete are improved， and an improved permeable concrete pavement is prepared. At the same time， ordinary permeable concrete pavement is prepared as a control. Based on the model tests under different rainfall reappearing periods， different rainfall intervals， the purification ability of the improved permeable concrete pavement system on typical runoff pollutants SS， COD， TN and TP is studied. The results show that the effect of improved permeable pavement on the removal of various pollutants decreases with the increase in the rainfall reappearing period； the removal ability of runoff pollutants by improved permeable concrete pavement is better than that of ordinary permeable concrete pavement. With the increase in rainfall interval time， the effluent concentration of COD and TP decreases firstly and then becomes stable， but the removal of SS and TN is less affected.

In order to explore the internal response mechanism and response degree of urbanization development and water resources utilization， and optimize the allocation of water resources， and coordinate the urban development speed and the degree of water resources development and utilization， the temporal and spatial distribution of water resources is taken as the cornerstone， a response model is constructed， the weight is determined by the entropy weight method， and the correlation analysis method analyzes the correlation between urbanization and water resources utilization. The results show that the urbanization development level and the utilization of water resources in the Poyang Lake Basin increases simultaneously. The upward trend of social， demographic， and spatial urbanization in the urbanization system is relatively synchronized， with large economic fluctuations and signs of decline in the early stage， but it has shown an increasing trend since 2016. The Poyang Lake Basin is a typical humid area. The resources endowment is greatly affected by rainfall， and the occurrence is unstable. Coupled with the rapid development of urbanization， the load of the water resources system is constantly loading. The development of urbanization has a great effect on the development and utilization of urban water resources. Urbanization has two-sided effects on the water resources system. On the one hand， a lot of water resources are consumed in the process of urbanization. On the other hand， the development of urbanization promotes the water resources system objectively.

Climate affects the spatial-temporal distribution of water resources. Studying the change characteristics of precipitation， a basic element of climate， has a guiding role in the planning and management of water resources in the basin. The Extreme-point Symmetric Mode Decomposition （ESMD） method is used to calculate the precipitation data of 51 meteorological stations in the Xijiang River Basin from 1954 to 2008. the spatiotemporal characteristics of annual precipitation， maximum and minimum daily precipitation over the year， flood season and non-flood season precipitation in the Xijiang River Basin are analyzed from three aspects： periods and abrupt changes， and wavelet analysis and other methods. The results show that： ① each precipitation indicator mainly has periodic characteristics such as 2， 14， 18 and 28 a， and the periodicity is consistent； ② the precipitation indicators have the most frequent abrupt changes in the 1960s， 1980s， and 1990s； ③ The annual minimum value and the non-flood season precipitation show a uniform positive growth linear trend； ④ The ESMD trend results of annual and non-flood season precipitation indicators in the middle and lower reaches are highly consistent. The ESMD method can effectively identify the change rule of non-stationary series， and opens up new ideas for the analysis of the spatiotemporal characteristics of precipitation.

In order to study the rainfall infiltration effect of different types of permeable pavement base structures， two kinds of physical models of permeable pavement are constructed in this paper. Recycled aggregate and ordinary graded gravel are used as base structure of these two different types of permeable pavement. The experiments of rainwater infiltration process of permeable pavement under three different rainfall intensities are carried out. The results show that under three different rainfall intensities， the peak time for the flow of recycled aggregate permeable pavement lags behind that of ordinary graded gravel permeable pavement， and the surface runoff generated is smaller， and the drainage time at the bottom of recycled aggregate permeable pavement is earlier than that of ordinary graded gravel permeable pavement. Therefore， recycled aggregate permeable pavement can increase the rainfall infiltration rate and reduce the surface runoff. The research results have important reference significance for the realization of rainwater resource utilization and the recycling of building demolition materials.

At present， there are some problems in domestic hydrometric stations， such as single function， disconnection of information collection and analysis， low coordination of system functions. To ameliorate these problems， an integrating hydrological monitoring， hydrological forecast， and hydrology and water conservancy calculation hydrological intelligent robot is designed. The robot has the following functions： self-inspection and automatic monitoring of hydrological monitoring equipment； real-time hydrological forecasting through communication technology and other historical information and observation information fusion and data assimilation； carrying out water conservancy evaluation intelligently； generating scheduling decision-making plans， and issuing forecasting and warning information. The intelligent robot system realizes a friendly human-computer interaction platform by means of language recognition and synthesis， which can simulate the thinking mode of hydrologists， change the one-way transmission mode of traditional equipment measurement， reporting， and calculation， and dynamically changes the measurement mode， position and frequency according to the rationality evaluation of forecasting and calculations. The proposed hydrological intelligent robot structure can replace the related functions of hydrological personnel at the basic station and in charge of flood control， reduce the labor intensity of hydrological work， and provide an important technical support for promoting the transformation of water conservancy undertakings to modernization and intelligence.

The scarcity and pollution of water resources affect the development of social economy and the optimization of water structure is an effective way to alleviate the pressure of water resources. In this paper， information entropy， equilibrium degree， Lorentz curve， Gini coefficient and other research methods are used to compare and analyze the temporal and spatial evolution characteristics of water use structures in seven geographical regions of China.The results show that China’s total water consumption shows a trend of rise and fall after fluctuations， and the balance of various types of water consumption is also rising slowly. Over time，the balance of East China， South China， Central China， Southwest China， and North China all exceeds that of the national level， while the water use structure in the Northwest and Northeast China is in an unstable state， and even the water use structure in the Northeast has become singular. In terms of spatial evolution， agricultural water is more evenly distributed in various regions of China， and industrial water and domestic water are more reasonable in most areas， the Gini coefficients for both water use in the Northwest region exceeds the “warning line”， while the Gini coefficients for most areas of ecological water use exceeds the “warning line”， and the coefficients in some areas are still increasing. Due to factors such as climate， geographical location， and socioeconomic development， water consumption in different districts needs to be considered. The analysis of the spatial and temporal evolution of water use structure is conducive to the optimization of water use structure， which is of great significance to the more efficient use of water resources and the coordinated development of society and economy.

Over the past few decades， the runoff in the upper reaches of the Fenhe River has been severely attenuated. Against this phenomenon， the long-term trends of annual rainfall， potential evapotranspiration， and runoff from 1961 to 2016 are analyzed. According to the mutation analysis of the annual runoff， the study period is divided into two stages （base period and change period）， the Choudhury-Yang formula based on Budyko’s hydro-thermal coupling balance theory is used to calculate the climatic elastic coefficient and the underlying surface elastic coefficient of the runoff in the basin. Attribution analysis of change in runoff is made. The results show that during 1961-2016， the runoff in the upstream water source area of the Fenhe River is significantly reduced， and the average annual runoff during the change-period is reduced by 35.5% compared with the base-period. The rainfall elasticity coefficient， potential evapotranspiration elasticity coefficient and underlying surface elasticity of runoff are 2.62， -1.62， -1.89； the underlying surface change caused by human activities is the main driving factor of runoff attenuation， with a contribution rate of 57.8%， followed by climate change， with a contribution rate of 42.2%： the decrease in rainfall contributed 39.7%， and the increase in average potential evapotranspiration contributed 2.5%. The large-scale soil and water conservation measures carried out in the upper reaches of the Fenhe River have not only reduced soil erosion and improved vegetation， but also increased actual evapotranspiration in the basin. In addition， the mining of coal has caused an increase in stratum fissures and surface subsidence， which has led to an increased rainfall infiltration， resulting in attenuation of runoff.

Satellite precipitation products serve as an important data supplement to ungauged or data-deficient region， whose temporal and spatial accuracy is crucial to hydrological simulation and prediction. The Yarlung Zangbo River Basin is a typical data-deficient region due to the high-cold mountainous location and extremely difficult for local observation. The applicability of the two satellite precipitation products， GSMap and GPM-IMERG， in this area is evaluated through the combination of quantitative indicators and classification indicators.The results show that both satellite precipitation products can accurately detect the occurrence of precipitation events. Compared with their previous generation TRMM satellite precipitation data， the two satellite precipitation data present higher accuracy （Bias<0.579）， the correlation is more significant （CC>0.902）， in contrast with the measured ground precipitation data. It is consistent for the spatial distribution of the correlation between the two types of satellite precipitation data and the ground-measured data，a strong correlation in the middle reaches of the river， and weak in the upstream and downstream. For the Yarlung Zangbo River Basin， GPM satellite precipitation products undertake better applicability than TRMM precipitation products， and could better meet the precipitation data requirements of water resources development and utilization. In the future， they can be integrated and assimilated with ground-based observation data to generate more reliable precipitation data products.

Huaibei plains is one of the important commercial grain production bases in China， with broad agricultural development prospects and strong demand for rural water conservancy construction. This study takes Geqiao Village and Songwan Village， Yingquan District， Fuyang City， Anhui Province， as the research area， and conducts the research from three aspects of rural drinking water， agricultural water-saving， and rural water system management. “Key rural water conservancy personnel” and households are investigated in the location. It is found that the water supply scale of rural residents in Huaibei Plains is insufficient； the water table is low； the collection mode of water fee is not conducive to the long-term operation of the water supply project； the participation degree of individual farmers in water-saving irrigation project is low； water-saving devices save labour but not water. Some suggestions， such as increasing regional water supply capacity， adjusting water charge mode， finding alternative surface water source， developing large-scale planting， carrying out agricultural water price reform and water-saving compensation， and increasing water system connectivity， are put forward.

In order to optimize the back wall structure of the box-culvert double flow channel， based on the CFX software， RNG K-? turbulence model is used to simulate the square， circular and ω shaped back wall， and the influence of different combinations on the flow pattern in the box culvert inlet and outlet channel is analyzed. The numerical results show that the flow pattern of the inlet channel with square back wall is better， but the flow pattern of the outlet channel is more disorderly， the flow velocity uniformity of the outlet channel section is poor， and the weighted average angle is low. The flow pattern of the inlet channel back wall is ω shape， and when the outlet channel back wall is circular， the flow pattern of the inlet and outlet channel is obviously improved. The uniformity of flow velocity and weighted average angle of the outlet section increases by 35.4% and 10.2° respectively. If the construction problem is considered， only the shape of the back wall of the outlet runner can be changed.

Regional drought acts as one of the major meteorological disasters in agricultural production，and drought index plays a fundamental role in drought monitoring and early warning. Taking Zhangye City as the research area，this paper analyzes the applicability of SPEI and scPDSI index.With a comparative analysis of two indices with relative humidity，runoff，normalized vegetation index （NDVI） and actual drought records，it shows that there is high consistency between scPDSI and drought history events and scPDSI has the most significant correlation with relative humidity，runoff and NDVI index. It indicates that scPDSI has good applicability in Zhangye. Based on scPDSI exponential change sequence，the characteristics of drought evolution in Zhangye from 1935 to 2017 are analyzed by M-K mutation test and wavelet periodic analysis. It is found that the study area shows a tendency to become wet after the 1980s，there are many dry and wet mutation points，with alternate cycles of drought and flood，and there are three distinct cycles of 24 a，14 a and 6 a. At the same time，changes of dry and wet cycle in Zhangye area may be related to solar activity and El Ni?o-Southern Oscillation （ENSO） activity. The research findings serve as a reference for the application of scPDSI in similar arid areas.

In order to study the pressure pulsation characteristics of the internal flow field of the mixed-flow pump device under different operating conditions， numerical calculation methods are used to analyze the pressure pulsation characteristics at the monitoring points of the water cone， horn， impeller outlet and pump outlet under different water level and flow conditions. The results show that the average pressure on the front and rear sides of the water guide cone and the horn tube increases with the increase in water level， and decreases with the increase in the flow rate， and the pressure difference between the front and rear sides is positively correlated with the flow rate. Under various working conditions， the main frequency of the pressure pulsation at the outlet and the pump outlet is the blade frequency， and there are obvious pressure fluctuations at the impeller outlet at the first 4 blade frequencies. Under high water level conditions， the pressure pulsation amplitude is smaller than the other two water levels.

Low specific speed centrifugal pumps are widely used in water conservancy， agriculture and industry. They are a kind of small flow and high head pumps. There is widespread sedimentation in rivers in our country， and the existence of solid particles will have a great impact on the flow components of centrifugal pumps. Under the solid-liquid two-phase condition， the setting of splitter blades can not only improve the performance of the centrifugal pump， but also its internal flow field to make its operation more stable and enhance the ability to transport two-phase media. When the particle size is within 0.5 mm， the head and efficiency of the low specific speed centrifugal pump with splitter blades may increase with the increase in particle diameter due to the flocculation of sediment. Under the solid-liquid two-phase condition， the abrasion of the middle and rear part of the suction surface of the centrifugal pump impeller blade is the most serious and is mainly caused by large-size particles.

Combined with EBM model and GML index， the agricultural water total factor productivity in 9 provinces in the Yellow River Basin from 2008 to 2018 is measured and decomposed from the national perspective. The results show that the total factor productivity of agricultural water resources in the Yellow River Basin is lower than that in the Yangtze River Economic Belt and the national average level. The growth of total factor productivity of agricultural water resources in the Yellow River Basin is mainly driven by technological progress， and its growth is limited by low technical efficiency. Water resources endowment and education level of rural labor have a positive impact on agricultural water total factor productivity in the Yellow River Basin， while water facilities and agricultural planting structure have a negative impact. In order to enhance the total factor productivity of agricultural water resources， the Yellow River Basin shall popularize high-efficiency water-saving irrigation means and improve the management level of agricultural water resources； improve the trans-regional water transfer mechanism， construct water conservancy facilities rationally， enhance the education level of rural labor force and optimize the agricultural planting structure.

In view of the influence of agricultural irrigation of reclaimed water on soil physical properties， soil fertility， soil environment， crop quality， human health and groundwater， this paper has systematically summarized the research advances by domestic and foreign scholars. The study results show that the effects of reclaimed water irrigation on soil physical properties， soil fertility， soil environment and crop quality are different， mainly due to the poor contrast of experiments， the connotation and extension of related concepts have not been unified， etc. It is generally believed that the risk to human health is at the acceptable level； and long-term reclaimed water irrigation will have a certain impact on groundwater environment. In order to provide more scientific theoretical guidance for agricultural irrigation of reclaimed water in China， this paper strengthens the research on the theoretical mechanism of reclaimed water for agricultural irrigation and carries out long-term and systematic monitoring work.

In order to improve the hydraulic efficiency of the guide vane mixed flow pump with a specific speed of 300， the standard orthogonal table is used to design the orthogonal test scheme of seven factors and three values including inlet and outlet angle， wrap angle， diameter of impeller and inlet and outlet angle， wrap angle of guide vane. Three-dimensional numerical simulation of the 18 mixed-flow pump designs is carried out with commercial software CFX. Range analysis is used to analyze the influence of various factors on the head and efficiency. The best program is selected according to the design requirements. Finally， by comparing and analyzing the internal flow before and after optimization， the reasons for the increase in the external characteristic parameters of the optimal plan are analyzed and explored. The results show that the installation angle of the impeller outlet has the greatest influence on the head and efficiency， and the installation angle of the guide vane outlet has the least influence on the head and efficiency. Under the design flow rate， the head of the optimal plan meets the optimization goal， the efficiency is significantly improved， and the overall flow pattern is improved to achieve the purpose of optimization design.

To make up for the structural defects of the existing damless water intake systems and improve their engineering design qualities， a new damless water intake system is designed according to the principles of mechanics， mechanism and electricity. By means of some simple mechanical components， this new system realizes the purposes of mechanical transmission and hydraulic water intake， reduces the requirements of flow and sediment conditions for the intake site selection and avoids the damages to the integrity and stability of the original riverbank by the water intake construction. Through sharing the middle sidewalls of the double helix channel， the construction cost of the grit chamber is reduced and its centralized land occupation is also convenient for the layout. Based on the characteristics of double helix geometry shape， bend flow movement and sediment deposition， the efficiency of sediment deposition is improved by the energy dissipation of bend helix flow.

The development of equipment and technology for the excavation of underground caverns of pumped-storage power stations is directly related to the safety of power station operations and the efficiency of production. Its excavation machinery and equipment have also gone through stages such as pneumatic drilling rigs and dobby trolleys. Traditional machinery and equipment cannot meet the requirements of major projects for construction efficiency， social benefits， and safety. Based on the research on the geology and construction conditions of the pumped storage power station， the key technology for the development of TBM for the pumped storage power station is proposed. For traffic tunnels and ventilation safety tunnels， drainage corridors， diversion inclined shafts and other projects， from TBM equipment design technology research has been carried out in the aspects of model selection， small radius turning technology， high-slope inclined shaft safety measures， and large-slope slagging technology. Through the successful application of the new TBM construction method of Shandong Wendeng Pumped Storage Power Station， the new TBM construction method can improve the efficiency and safety of underground cavern excavation， and has the prospect of popularization and application.

The turbine governor is the key core equipment for controlling the process of hydroelectric power generation. The unsettled neutral position of main distribution gas will lead to frequent regulation of main distribution， which seriously threatens the safe and stable operation of units and power grid.In order to solve the problem of frequent adjustment of main distribution， the scientific research team has carried out in-depth research on the hydraulic servo system of the governor. By establishing a mathematical model， static and dynamic balance theory is put forward， and a series of technical methods such as automatic diagnosis method， automatic setting method， direct setting method and improved direct setting method for accurate and fast setting of neutral in main distribution gas are explored on the basis of defining reasons for the frequent adjustment of main distribution.This technical method is successfully applied in the field control software of governor， realizing the function of automatic diagnosis and intelligent setting of neutral position in the main distribution gas.Field test and operation results show that this technical achievement realizes the automation of neutral setting in main distribution gas during unit overhaul， solves the problem of frequent adjustment of main distribution in governor system effectively and ensures safe and stable operation of unit and power grid.

In order to analyze the dynamic response characteristic of typical hydraulic transient process conditions in super-long and large water diversion and power generation system， this paper takes JPII Hydropower Station （8 × 600 MW） as an example. The HYSIM simulation models of main elements in the system are established by the user-defined modeling function of HYSIM software，such as differential surge tank， Francis turbine， ring gate and so on. Based on the internal mechanism and operating characteristics of the system， the complete simulation model of the super-long and large water diversion and power generation system has been completed finally. Besides， the method of parameter calibration and correction for the main elements of the system is proposed. By the simulation model， two typical hydraulic transient process test conditions are simulated， here the involved test conditions are as follows： double load rejection and shun-down process of ring valve. At the same time， the calculated results are compared with the test results. The results show that the proposed simulation model can describe the dynamic response characteristic of the super-long and large water diversion and power generation system accurately and it can provide a reliable simulation platform for checking the extreme control conditions and studying long-term stable operation mechanism of the system.

Noise is a great disturbance in the analysis of vibration signals， which is an important part in fault diagnosis. In this paper， a denoising method based on Variational Mode Decomposition and soft Wavelet-thresholding is proposed. The new method works better than the EMD one in that it solves the EMD’s inherent defects like modal aliasing， endpoint effect and weak robotness to noises. A rotor test bed is used to generate signals in four different working conditions： misaligned rotor， unbalanced rotor， healthy rotor and rotor contact-rubbing. These signals are first decomposed by VMD and then， the high frequencies are denoised by soft wavelet-thresholding and then reconstructed with the remains. Lastly， signal to noise analysis is conducted to the reconstructed signals. The results show that the signal to noise ratio of VMD method basically doubles the EMD one. Therefore， it is confirmed that this method has a better effect on denoising than the EMD one.

In the dynamic nonlinear numerical simulation analysis of earth-rock dams， reasonable artificial boundary conditions can correctly simulate the wave propagation characteristics at the boundary of the model and improve the numerical calculation accuracy. This paper takes multiple earth-rock dams near Tibet as an example， uses finite element and infinite element methods to compare and analyze the nonlinear dynamic response laws of earth-rock dams under different boundary conditions based on ABAQUS software. It analyzes the influence of boundary conditions on the dynamic response results under different working conditions， different overburden depths， and different input seismic wave amplitudes. The results show that the accuracy of the numerical simulation results of the infinite element boundary and the viscoelastic boundary are both high， and the viscoelastic boundary can reflect the earthquake action mechanism more truly.

High-speed water flow energy dissipation is the most important hydraulic problem in high head water conservancy and hydropower projects. At present， applying discontinuous beam shrinkage internal energy dissipation in high flow velocity and pressure-free tunnel has not occurred before. A numerical simulation of spillway of a hydropower station is carried out by using flow-3D software， and the feasibility of internal energy dissipation in the arrangement of pressure-free tunnel of high-velocity spillway is verified. In the initial stage， triangular piers with simple structure are used to analyze the energy dissipation effects of energy dissipation piers with different beam narrowness and slope ratio. Aiming at the defect of triangular pier，this paper puts forward the solution of hump type energy dissipating pier. The symmetrical hump piers with 10% beam narrowness along the tunnel section are finally determined， and the spillway physical model with a scale of 1∶80 is established to verify the calculation accuracy of flow-3D software. The experimental results show that the hump piers are arranged along the tunnel with ideal energy dissipation effect， but the hump type piers still have the problem of water wing over the pier and large negative pressure at the peak， and further body optimization is needed. Cavitation erosion and water wing problems of hump piers with optimized flow lines are improved effectively.

To build a water conservancy project on a river， it is necessary to consider its comprehensive benefits in flood control， power generation， navigation， irrigation and so on.According to the analysis of navigation， the shiplock is a navigable building arranged on the hub， and the flow situation of the diversion channel should meet the navigation conditions. Among them， the gate area is the connecting section of the channel and the natural waterway， which is affected by the boundary mutation and so on， and the flow condition is complicated， which often does not meet the navigation requirements.In this paper， according to the project layout， river characteristics and navigation requirements of the run-off hydropower station， four dredging schemes are designed on the basis of the original design scheme， Under the conditions of discharge of 350， 1 570.4， 6 200 and 12 000 m³/s， the flow conditions of the lock entrance area are demonstrated by the mathematical model， and the conclusion that the fourth dredging scheme can meet the flow conditions of the downstream entrance area of the approach channel and the navigation requirements of class Ⅲ waterway is obtained. The research results in this paper can provide the optimal design and navigation demonstration of navigation conditions of run-off hydropower stations， and provide reference for similar projects.

In view of the problems of underground power-house of hydropower station， such as perennial humid and hot， with the characteristics of traditional and single， lead to poor ventilation. This paper takes the engineering design of the ventilation system of a hydropower station in southwest China as an example and explores the intelligent transformation of the ventilation system of an underground powerhouse of hydropower station through online monitoring and on-site control and other technical means. the structure and function of the monitoring system and the off-line test are introduced in detail， and the intelligent renovation scheme of the ventilation system in the underground powerhouse of a certain hydropower station in the southwest of China is put forward. With the characteristics of low cost， perfect function， a high degree of automation and intelligence， this system meets the production and operation requirements of hydropower stations and is conducive to the realization of the production and management mode of “remote centralized control， few people maintenance” of hydropower stations.

Based on the panel data of 124 county-level cities along the middle route of South-to-North Water Transfer Project from 2003 to 2015， Moran index and spatial econometric model are used to analyze the spatial correlation characteristics and water consumption competition of cities along the middle route of South-to-North Water Transfer Project. The results show that the urban total water demand along the middle route of South-to-North Water Transfer Project is characterized by “multi-point agglomeration and local diffusion.” After the implementation of the project， the water competition between adjacent areas weakened， and the fierce water resources competition between economically developed areas changed into water cooperation. Locally， after the implementation of the project， the competition for water use between regions with strong economic ties in Henan Province intensified， while the competition for water use in Beijing-Tianjin-Hebei region weakened， and Beijing and related regions showed a cooperative relationship in water use. Taking big cities as the center， it is an important measure to improve the spatial utilization of water resources and the efficiency of water resources allocation to implement the cascade allocation of water resources in the surrounding areas of central cities according to the scale of economic population.

In the pumping station system for long-distance water transportation， air tanks are being used more and more widely. In the past water transportation projects， air tanks were generally installed in the pump room to adjust the boost and negative pressure generated by accidental pumping. The effect is more significant than that of surge tanks and air valves. With the increasing number of water transfer projects in our country， the research on the water hammer protection method of setting up air tanks is gradually being carried out. The characteristic parameters of the air tank have a deep influence on its water hammer protection effects， such as water-to-air ratio， pre-charge pressure， import and export resistance coefficients， etc. Based on an actual water delivery project， PIPENET hydraulic analysis software is used to set the water hammer of the air tank The protection scheme is analyzed and calculated， and the influence of the resistance coefficient of the inlet and outlet of the air tank on its water hammer protection effect is studied. By comparing multiple sets of calculation results， the law of the influence of the import and export resistance coefficient on the protection effect is obtained. The greater the air tank inlet resistance， the more beneficial the control of positive pressure， and the smaller the outlet resistance， the more advantageous the control of negative pressure. Research show that in engineering practice， the cost and protection effect can be improved by changing the resistance coefficients of the air tank inlet and outlet.