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Dynamic simulation and optimization approach to construction diversion of hydraulic and hydroelectric projects

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Science China(Technological Sciences) 2009年第7期52卷 1990-1998页

作者： ZHONG DengHua LI MingChao HUANG Wei LIU Yong Department of hydraulic and hydroelectric engineering School of Civil EngineeringTianjin UniversityTianjin 300072China

To solve the engineering and scientific problems in construction diversion and its simulation analysis, a complete scheme is presented. Firstly, the complex constraint relationship was analyzed among main buildings, diversion buildings and flow control. Secondly, the time-space relationship model of construction diversion system and the general block diagram-oriented simulation model of diversion process were set up. Then, the corresponding numerical simulation method and 3D dynamic visual simulation method were put forward. Further, the simulation and optimization platform of construction diversion control process was developed, integrated with simulation modeling, computation and visualization. Finally, these methods were applied to a practical project successfully, showing that the modeling process is convenient, the computation and the visual analysis can be coupled effectively, and the results conform to practical state. They provide new theoretical principles and technical measures for analyzing the control problems encountered in construction diversion of hydraulic and hydroelectric engineering under complex conditions.

关键词： construction diversion dynamic simulation optimization analysis block diagram hydraulic and hydroelectric project

Real-time compaction quality monitoring of high core rockfill dam

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Science China(Technological Sciences) 2011年第7期54卷 1906-1913页

作者： ZHONG DengHua LIU DongHai CUI Bo Department of hydraulic and hydroelectric engineering School of Civil Engineering Tianjin University Tianjin 300072 China

The conventional quality control method of core rocldill dam construction exhibit difficulty controlling compaction parameters accurately or ensuring construction quality. This is because it is easily influenced by human behavior or lack of adequate management. We therefore establish the timely monitoring indexes and control criteria of compaction processes by considering the characteristics and quality requirements of high core rockffll dam construction. Based on the established indexes and criteria, integrating GPS, GPRS and PDA technologies, a real-time compaction quality monitoring method is proposed. The relevant key techniques are proposed as well, including automatic collection of information and a graphic algorithm for rolling-process visualization. By the proposed method and techniques, a real-time monitoring system is provided to realize the precise automatic online entire-process monitoring of compaction parameters, including compaction pass, rolling trajectory, nmning speed of roller, vibration status and rolled pavement thickness. The application of the Nuozhadu project shows that the proposed system can control compaction parameters effectively and ensure better construction quality. Therefore, it might become a new way towards construction quality control of high core rockfill dam.

关键词： core rockfill dam compaction quality real-time monitoring quality control

3D integrated modeling approach to geo-engineering objects of hydraulic and hydroelectric projects

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Science China(Technological Sciences) 2007年第3期50卷 329-342页

作者： ZHONG DengHua LI MingChao LIU Jie Department of hydraulic and hydroelectric engineering School of Civil EngineeringTianjin UniversityTianjin 300072China

Aiming at 3D modeling and analyzing problems of hydraulic and hydroelectric en-gineering geology,a complete scheme of solution is presented. The first basis was NURBS-TIN-BRep hybrid data structure. Then,according to the classified thought of the object-oriented technique,the different 3D models of geological and engi-neering objects were realized based on the data structure,including terrain class,strata class,fault class,and limit class;and the modeling mechanism was alterna-tive. Finally,the 3D integrated model was established by Boolean operations be-tween 3D geological objects and engineering objects. On the basis of the 3D model,a series of applied analysis techniques of hydraulic and hydroelectric engineering geology were illustrated. They include the visual modeling of rock-mass quality classification,the arbitrary slicing analysis of the 3D model,the geological analysis of the dam,and underground engineering. They provide powerful theoretical prin-ciples and technical measures for analyzing the geological problems encountered in hydraulic and hydroelectric engineering under complex geological conditions.

关键词： 3D integrated model engineering geology geological analysis hydraulic and hydroelectric project

Theoretical research on construction quality real-time monitoring and system integration of core rockfill dam

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Science China(Technological Sciences) 2009年第11期52卷 3406-3412页

作者： ZHONG DengHua CUI Bo LIU DongHai TONG DaWei Department of hydraulic and hydroelectric engineering School of Civil EngineeringTianjin UniversityTianjin 300072China

With the enlargement of core rockfill dam construction scale and the improvement of construction mechanization level, the traditional manual construction quality control method is now difficult to meet the quality and safety demands of modern dam construction, so automatic and real-time dam construction quality monitoring with high-techs is urgently needed. The paper makes theoretical research on construction quality real-time monitoring and system integration of core rockfill dam, proposes implementation method and integrated solution of construction quality real-time monitoring of core rockfill dam construction process, realizes refining, all-whether, entire-process and real-time control and analysis on key links of dam construction, and introduces the application of the construction quality real-time monitoring and system integration technology to a practical core rockfill dam project.

关键词： core rockfill dam construction quality real-time monitoring system integration

Distribution of acceleration and empirical formula for calculating maximum acceleration of rockfill dams

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Journal of Central South University 2010年第3期17卷 642-647页

作者：周晖李俊杰康飞 Institute of hydraulic and hydroelectric engineering Dalian University of Technology Faculty of Infrastructure engineering Dalian University of Technology

To find the distribution patterns of dynamic amplification coefficients for dams subjected to earthquake, 3D seismic responses of concrete-faced rockfill dams with different heights and different shapes of river valley were analyzed by using the equivalent-linear model. Statistical analysis was also made to the seismic coefficient, and an empirical formula for calculating the maximum acceleration was provided. The results indicate that under the condition of the same dam height and the same base acceleration excitations, with the increase of the river valley width, the position of the maximum acceleration on the axis of the top of the dam moves from the center to the riversides symmetrically. For the narrow valleys, the maximum acceleration occurs in the middle of the axis at the top of the dam; for wide valleys the maximum acceleration appears near the riversides. The result negates the application of 2D dynamical computation for wide valleys, and shows that for the seismic response of high concrete-faced rockfill dams, the seismic coefficient along the axis should be given, except for that along the dam height. Seismic stability analysis of rockfill dams using pseudo-static method can be modified according to the formula.

关键词： concrete-faced rockfill dam 3D dynamical response analysis equivalent-linear method acceleration seismic coefficient statistical analysis

hydraulic CHARACTERISTICS OF VERTICAL VORTEX AT hydraulic INTAKES

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Journal of Hydrodynamics 2007年第2期19卷 143-149页

作者： CHEN Yun-liang WU Chao YE Mao JU Xiao-ming State Key Laboratory of hydraulics and Mountain River engineering Sichuan University Chengdu 610065China college of hydraulic and hydroelectric engineering Sichuan University Chengdu 610065 China

The trace of vertical vortex flow at hydraulic intakes is of the shape of spiral lines, which was observed in the presented experiments with the tracer technique. It represents the fluid particles flow spirally from the water surface to the underwater and rotate around the vortex-axis multi-cycle. This process is similar to the movement of screw. To describe the multi-circle spiral characteristics under the axisymmetric condition, the vertical vortex would change not only in the radial direction but also in the axial direction. The improved formulae for three velocity components for the vertical vortex flow were deduced by using the method of separation of variables in this article. In the improved formulae, the velocity components are the functions of the radial and axial coordinates, so the multi-circle spiral flow of vertical vortex could be simulated. The calculated and measured results for the vertical vortex flow were compared and the causes of errors were analyzed.

关键词： vertical vortex tracer technique multi-circlespiral flow separation of variables

THEORETICAL AND EXPERIMENTAL STUDIES OF THE FLARING GATE PIER ON THE SURFACE SPILLWAY IN A HIGH-ARCH DAM

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Journal of Hydrodynamics 2012年第4期24卷 496-505页

作者： LI Nai-wen LIU Chao DENG Jun ZHANG Xiao-zhe State Key Laboratory of hydraulics and Mountain River engineering Sichuan University Chengdu 610065China college of hydraulic and hydroelectric engineering Sichuan University Chengdu 610065 China

The experimental studies of the flaring gate pier applied on the surface spillway in a high-arch dam show that a shock-wave will appear when the pattern of the flow is kept as super-critical. Meanwhile, the water depth at the outlet increases significantly, the flow moves downward in different directions, and the plunging jet is in a narrow and long shape, with a full longitudinal diffusion. In addition, the variation of the flaring gate pier design parameters affects little the discharge capacity of the surface spillway, these parameters including the contraction ratio fl, the contraction angle c~ and the spillway chute angle O. The pressure on the bottom of the spillway increases along the way and reaches the maximum before the outlet, and then decreases rapidly. Due to the flow impacting, the pressure on both sidewalls increases abruptly at the turning line of the flaring gate pier. To see the characteristics of the flow in the flaring gate pier, a simple calculation method is suggested based on the conversation of energy and mass, and the calculation methods for the jet trajectory and the horizontal length in air are also proposed. The results are found in good agreement with experimental data.

关键词： high-arch dam flood discharge and energy dissipation flaring gate pier hydraulic calculation jet trajectory distance

Research on analysis method for temperature control information of high arch dam construction

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Science China(Technological Sciences) 2011年第S1期54卷 40-46页

作者： ZHONG DengHua,ZHAO ChenSheng & REN BingYu Department of hydraulic and hydroelectric engineering,School of Civil engineering,Tianjin University,Tianjin 300072,China 1. Department of hydraulic and hydroelectric engineering School of Civil Engineering Tianjin University Tianjin 300072 China

Temperature control,which is directly responsible for the project quality and progress,plays an important role in high arch dam *** to discover the rules from a large amount of temperature control information collected in order to guide the adjustment of temperature control measures to prevent cracks on site is the key scientific *** this paper,a mathematic logical model was built firstly by means of a coupling analysis of temperature control system decomposition and coordination for high arch ***,an analysis method for temperature control information was presented based on data mining ***,the data warehouse of temperature control was designed,and the artificial neural network forecasting model for the highest temperature of concrete was also ***,these methods were applied to a practical project. The result showed that the efficiency and precision of temperature control was improved,and rationality and scientificity of management and decision-making were *** of these researches provided an advanced analysis method for temperature control in the high arch dam construction process.

关键词： high arch dam construction temperature control information data mining data warehouse neural network model

Flow patterns and boundary conditions for inlet and outlet conduits of large pump system with low head

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Applied Mathematics and Mechanics(English Edition) 2014年第6期35卷 675-688页

作者：徐磊陆伟刚陆林广董雷王兆飞 college of hydraulic Science and engineering Yangzhou University

The flow patterns in the inlet and outlet conduits have a decisive effect on the safe, stable, and highly efficient operation of the pump in a large pumping station with low head. The numerical simulation of three-dimensional （3D） turbulence flow in conduits is an important method to study the hydraulic performance and conduct an optimum hydraulic design for the conduits. With the analyses of the flow patterns in the inlet and outlet conduits, the boundary conditions of the numerical simulation for them can be determined. The main obtained conclusions are as follows：（i） Under normal operation conditions, there is essentially no pre-swirl flow at the impeller chamber inlet of an axial-flow pump system, based on which the boundary condition at the inlet conduit may be defined. （ii） The circulation at the guide vane outlet of an axial-flow pump system has a great effect on the hydraulic performance of the outlet conduit, and there is optimum circulation for the performance. Therefore, it is strongly suggested to design the guide vane according to the optimum circulation. （iii） The residual circulation at the guide vane outlet needs to be considered for the inlet boundary condition of the outlet conduit, and the value of the circulation may be measured in a specially designed test model.

关键词： flow pattern boundary condition inlet conduit outlet conduit pump system low head