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On the Increased Precipitation Recycling by Large-Scale Irrigation over the Haihe Plain

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Journal of Meteorological Research 2022年第3期36卷 450-461页

作者： Yunpeng GUI Qingming WANG Yong ZHAO Mengyang MA Haihong LI Jiaqi ZHAI Enchong LI department of hydraulic Engineering Tsinghua UniversityBeijing 100084 State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin Institute of Water Resources and Hydropower ResearchBeijing 100038

Irrigation not only plays an important role in global food security,but it also affects aspects of the regional climate,including *** this study,we proposed a simple and convenient method to quantify the contribution of large-scale irrigation to precipitation by distinguishing the amount of evaporation generated by irrigation from local evaporation based on the precipitation recycling method.A case study was presented to show the increased precipitation recycling ratio and the contribution of irrigation to precipitation during the main irrigation period in the Haihe Plain from 1961 to *** found that the average precipitation recycling rates in the Haihe Plain are 8.32%,9.74%,and 10.36%in April,May,and June,*** contribution rates of irrigation to precipitation in the Haihe Plain are 3.76%,5.12%,and 2.29%in April,May,and June,*** total contribution of irrigation to precipitation during the main irrigation period is 3.77 mm;the respective contributions in April,May,and June are 0.72,1.70,and 1.35 *** contribution of irrigation to local precipitation is relatively small as the inflow of atmospheric moisture during the irrigation period is still the main factor affecting local ***,this part of the precipitation during the irrigation period alleviates the water shortage in the Haihe Plain to some extent.

关键词： irrigation precipitation recycling contribution of irrigation to precipitation Haihe Plain

Study on the holistic model for water resources system

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Science China(Technological Sciences) 2004年第Z1期47卷 72-89页

作者： ZHAO Jianshi WANG Zhongjing WENG Wenbin department of hydraulic Engineering Tsinghua University Beijing 100084 China Department of Hydraulic Engineering Tsinghua University Beijing 100084 China Department of Hydraulic Engineering Tsinghua University Beijing 100084 China

Based on the Theory of Complex Adaptive System developed recently, a holistic model for water resources system is established at the basin level for analyzing water resources management and allocation of the basin. In this holistic model framework, the subsystems of the water resources system, including hydrologic components, agricultural and industrial production, human living, ecosystem and enviorenment are combined in a dynamic connection with inner variables. According to the characteristics of the holistic model framework, a nesting genetic arithmetic is employed to solve the nonlinear optimal model. The model is applied in the Yellow River basin to analyze the rational amount of diversion water for the West Line of Water Transfer Project form South China to North China and its marginal benifit.

关键词： water resources, holistic model, complex adaptive system, genetic arithmetic.

Comprehensive two-dimensional river ice model based on boundary-fitted coordinate transformation method

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Water Science and Engineering 2014年第1期7卷 90-105页

作者： Ze-yu MAO Jing YUAN Jun BAO Xiao-fan PENG Guo-qiang TANG department of hydraulic Engineering Tsinghua University

River ice is a natural phenomenon in cold regions, influenced by meteorology, geomorphology, and hydraulic conditions. River ice processes involve complex interactions between hydrodynamic, mechanical, and thermal processes, and they are also influenced by weather and hydrologic conditions. Because natural rivers are serpentine, with bends, narrows, and straight reaches, the commonly-used one-dimensional river ice models and two-dimensional models based on the rectangular Cartesian coordinates are incapable of simulating the physical phenomena accurately. In order to accurately simulate the complicated river geometry and overcome the difficulties of numerical simulation resulting from both complex boundaries and differences between length and width scales, a two-dimensional river ice numerical model based on a boundary-fitted coordinate transformation method was developed. The presented model considers the influence of the frazil ice accumulation under ice cover and the shape of the leading edge of ice cover during the freezing process. The model is capable of determining the velocity field, the distribution of water temperature, the concentration distribution of frazil ice, the transport of floating ice, the progression, stability, and thawing of ice cover, and the transport, accumulation, and erosion of ice under ice cover. A MacCormack scheme was used to solve the equations numerically. The model was validated with field observations from the Hequ Reach of the Yellow River. Comparison of simulation results with field data indicates that the model is capable of simulating the river ice process with high accuracy.

关键词： two-dimensional river ice numerical model boundary-fitted coordinate technology river ice process freeze-up MacCormack scheme natural river

Employment of mud-pulse generator for improvement of efficiency of a wellbore producing in complex mining and geological conditions

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Petroleum Research 2024年第1期9卷 92-97页

作者： Bibinur Akhymbayeva department of Petroleum Engineering Satbayev University05001322 Satpayev Str.AlmatyKazakhstan

In this study,the employment of mud-pulse generators to improve the efficiency of wellbores under complex mining and geological conditions is examined.A systemic analysis is made of the primary theoretical basis of the *** benefits of a mud-pulse generator(a high-impulse hydraulic hammer)for wellbore production are stated based on the presented theoretical *** results not only show the benefits of mud-pulse generator employment but also provide an analysis of methods that can be used to improve the high-impulse hydraulic hammer *** acquired results have a substantial practical value not only for specialists,who research,develop,and manage wellbore operations,but also for engineers,who improve the process and modernize existing wellbores,and other experts in the field of wellbore production.

关键词： Fossil energy sources High-pulse hydraulic hammer Wellbore production technology The efficiency of wellbore usage Hydro-impulse systems

A simplified dynamic method for field capacity estimation and its parameter analysis

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Water Science and Engineering 2014年第4期7卷 351-362页

作者： Zhen-tao CONG Hua-fang Lü Guang-heng NI department of hydraulic Engineering Tsinghua University

This paper presents a simplified dynamic method based on the definition of field capacity. Two soil hydraulic characteristics models, the Brooks-Corey （BC） model and the van Genuchten （vG） model, and four soil data groups were used in this study. The relative drainage rate, which is a unique parameter and independent of the soil type in the simplified dynamic method, was analyzed using the pressure-based method with a matric potential of -1/3 bar and the flux-based method with a drainage flux of 0.005 cm/d. As a result, the relative drainage rate of the simplified dynamic method was determined to be 3% per day. This was verified by the similar field capacity results estimated with the three methods for most soils suitable for cultivating plants. In addition, the drainage time calculated with the simplified dynamic method was two to three days, which agrees with the classical definition of field capacity. We recommend the simplified dynamic method with a relative drainage rate of 3% per day due to its simple application and clearly physically-based concept.

关键词： field capacity simplified dynamic method pressure-based method flux-basedmethod soil water HYDRUS

Coordinated deformation control technologies for the high sidewall—bottom transfixion zone of large underground hydro-powerhouses

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第7期23卷 543-563页

作者： Qi-xiang FAN Zhi-yun DENG Peng LIN Guo LI Ji-lin FU Wei HE China Huaneng Group Co. Ltd.Beijing100031China China Three Gorges Group Corporation Beijing100038China department of hydraulic Engineering Tsinghua UniversityBeijing100084China

It is imperative to understand the spatial and temporal coordination deformation mechanism and develop targeted deformation control technologies for high sidewall—bottom transfixion(HSBT)zones to guarantee the stability of rock surrounding underground hydro-powerhouses under complex geological *** this study,the spatial and temporal coordinated deformation control of HSBT zones was addressed from the aspects of the deformation mechanism,failure characteristics,and control requirements,and some coordinated deformation control technologies were *** this basis,a case study was conducted on the deformation control of the HSBT zone of the underground powerhouse at the Wudongde hydropower station,*** results showed that the relationship between excavation and support,and the mismatch of deformation and support of the surrounding rock mass in the HSBT zone of underground caverns with a large span and high in-situ stress can be appropriately *** solution requires proper excavation and construction procedures,fine blasting control,composite and timely support,and real-time monitoring and dynamic *** technologies proposed in this study will ensure the safe,high-quality,and orderly construction of the Baihetan and Wudongde underground caverns,and can be applied to other similar projects.

关键词： Underground powerhouse Coordinated deformation mechanism High sidewall-bottom transfixion(HSBT) Cavern group Control technology

Significance of including lid thickness and particle shape factor in numerical modeling for prediction of particle trap efficiency of invert trap

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Water Science and Engineering 2024年第2期17卷 166-176页

作者： Salman Beg Deo Raj Kaushal department of Civil Engineering Indian Institute of Technology DelhiNew Delhi 110016India

Sediment accumulation on the bed of open sewers and drains reduces hydraulic efficiency and can cause localized *** invert traps installed underneath the bed of open sewers and drains can eliminate sediment build-up by catching sediment *** three-dimensional(3D)computational studies have examined the particle trapping performance of invert traps of different shapes and depths under varied sediment and flow conditions,considering particles as *** two-dimensional and 3D numerical modeling,researchers assumed the lid geometry to be a thin line and a plane,*** this 3D numerical study,the particle trapping efficiency of a slotted irregular hexagonal invert trap fitted at the flume bottom was examined by incorporating the particle shape factor of non-spherical sewage solid particles and the thicknesses of upstream and downstream lids over the trap in the discrete phase model of the ANSYS Fluent 2020 R1 *** volume of fluid(VOF)and the realizable k-turbulence models were used to predict the velocity *** two-dimensional particle image velocimetry(PIV)was used to measure the velocity field inside the invert *** results showed that the thicknesses of upstream and downstream lids affected the velocity field and turbulent kinetic energy at all flow *** joint impact of the particle shape factor and lid thickness on the trap efficiency was *** both the lid thickness and particle shape factor were considered in the numerical modeling,trap efficiencies were underestimated,with relative errors of-8.66%to-0.65%in comparison to the experimental values of Mohsin and Kaushal(2017).They were also lower than the values predicted by Mohsin and Kaushal(2017),which showed an overall overestimation with errors of-2.3%to 17.4%.

关键词： Invert trap Lid thickness Particle image velocimetry Particle shape factor Turbulent kinetic energy Scanning electron microscope

Flood Velocity Prediction Using Deep Learning Approach

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Journal of Geodesy and Geoinformation Science 2024年第1期7卷 59-73页

作者： LUO Shaohua DING Linfang TEKLE Gebretsadik Mulubirhan BRULAND Oddbjørn FAN Hongchao department of Civil and Environmental Engineering Norwegian University of Science and TechnologyTrondheim 7034Norway

Floods are one of the most serious natural disasters that can cause huge societal and economic *** research has been conducted on topics like flood monitoring,prediction,and loss *** these research fields,flood velocity plays a crucial role and is an important factor that influences the reliability of the *** methods rely on physical models for flood simulation and prediction and could generate accurate results but often take a long *** learning technology has recently shown significant potential in the same field,especially in terms of efficiency,helping to overcome the time-consuming associated with traditional *** study explores the potential of deep learning models in predicting flood *** specifically,we use a Multi-Layer Perceptron(MLP)model,a specific type of Artificial Neural Networks(ANNs),to predict the velocity in the test area of the Lundesokna River in Norway with diverse terrain *** data and flood velocity simulated based on the physical hydraulic model are used in the study for the pre-training,optimization,and testing of the MLP *** experiment indicates that the MLP model has the potential to predict flood velocity in diverse terrain conditions of the river with acceptable accuracy against simulated velocity results but with a significant decrease in training time and testing ***,we discuss the limitations for the improvement in future work.

关键词： flood velocity prediction geographic data MLP deep learning

A Study on Impervious and Heat-Insulating Performance of Geomembrane Composites Within Breakwater

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China Ocean Engineering 1997年第2期12卷 213-224页

作者： Tao, TK Yu, L Yan, J Dong, ZY hydraulic Engineering department Nanjing Hydraulic Research Institute Nanjing 210029 China

This paper investigates the performance of geomembrane composites used as impervious and heat-insulating lining within a breakwater for a power station. The seepage field, distribution of stress-strain contour and seepage discharge of hot water which has been treated as the inner thermal source in the calculation of heat-insulation, have been given by three-dimensional calculation method coupling seepage with stress. The results indicate that the impervious and heat-insulation effect of geomembrane composites is significant.

关键词： breakwaters geomembrane composite impervious and heat-insulation