| Zhou Xiaoyang Ma Yinwu Zhang Yongchuan |
| (Huazhong University of Science & Technology) |
Abstract Based on the analysis of the energy transform law of cascade reservoirs,a new concept of energy gain transform is introduced and the condition for transformation is deduced.The cascade reservoirs energy is described by using tank-reservoir proposed in this paper.A practical rule of total tank-reservoir energy gain transform is established.This method is useful in estabilishment of cascade reservoirs dispatch model.
Key words cascade reservoirs,energy gain transfrom,tank-reservoir model.
| Zhou Xiaoyang Ma Yinwu Zhang Yongchuan |
| (Huazhong University of Science & Technology) |
Abstract In this paper,a nonlinear real time dispatch functionis established.The optimal dispatch rule is identified by solving a stochastic optimal model for cascade reservoir dispatch.Since the structure of the dispath model is modified and the effect of dimensional disaster is reduced,the result of simulation calculation is satisfactory.
Key words real time dispatch function,optimal dispatch rule,parameter identification.
| Liu Tianyun Liu Guangting |
| (Tsinghua University) |
Abstract A reasonable procedure is proposed to calculate the free response of arch dam in canyon. It makes the determination of dynamic stiffness of the foundation easier and the input of the free field is very simple. Response to different incident conditions of P and SV waves are analyzed in frequency domain. The calculation results show that this approach can effectively reflect the magnifying effect of the canyon banks, amplitude difference and phase difference. The procedure is applied to engineering practive.
Key words substructure, structure soil interaction, free field response.
| Tian Yuan |
| (Lanzuou University) |
| Su Derong Yang Jurui |
| (Gansu Agricultural University) |
Abstract In this paper, a matrix model is developed by dividing the system into subsystems and subunits. The indices for evaluation of pump aging are introduced and the aging matrix analysis model for multi grad pumping station is established. A case study is given.
Key words multi grade pumping station, pump, aging, simulating model.
| Ni Hangen |
| (Dalian University of Technology) |
Abstract Based on the dynamic equation of bubble, a simple relationship between incipient cavitaion number of prototype and model is established with the approximation of the terms in the equation taken into account. A typical radius of bubble during cavitation inception is determined according to the observation data. The relationship is verified by the model test results of a spillway tunnel with different scales.
Key words cavitation, inception, scale effect, model test.
|
Abstract Throught the analysis of the physical meaning represented by Ляпунов function being constructed, this paper considers that Ляпунов′s stability judgement terms are too harsh on the discussion of water level oscillating stability in the surge tank of water power station. The developed stability judgement terms are provided and applied in the study on the water level oscillating stability. The results of the study is in good agreement with the numerical calculation.
Key words qualitative theory, stability, surge tank, stable section.
| Liu Yingxi Li Shouju |
| (Dalian University of Technology) |
| Chen Changli Li Zhengguo |
| (Fengman Hydraulic Power Plant) |
| Lu Zhengang |
| (Baishan Hydraulic Power Plant) |
Abstract Based upon the observed displacement data of the dam crest,the component of horizontal displacement caused by impounded water has been separated by using progressive regressive method.According to the least square object function,the normalized least square parameter identification method has been established.The numerical computation results show that this method is effective for identifying elastic moduli of dam concrete and rock basement based on crest horizontal displacement.The method possesses good stability and quick convergence speed.The forecast concrete modulus is in good agreement with the insitu test result.
Key words parameter identification, concrete gravity dam,elastic modulus, the least square method, stability.
| Wang Xuegong Zuo Dunhou |
| (Anhui and Huai River Water Resources Research Institute) |
Abstract Based on the assumption that the water surface is a straight line,the equation of hydraulic jump on a folded slope is deduced.The folded slope is approximately regarded as a single slope with a slope of tgθ′。The effectiveness of this method is verified by experimental result.
Key words hydraulic jump,equation, folded slope.
| Liu Hanlong |
| (Hohai University) |
| Zhou Jian |
| (Tongji University) |
Abstract In order to identify the damage mechanism of breakwater during the strong earthquake occurred to Hanshin, Japan, 1995, an effective stress analysis is performed with the interaction of soil structure water taken into account. The nonlinear constitutive model used in the study is a multiple shear mechanism type in strain space and the effect of rotation of principal stress axis direction has been considered. The result of numerical simulation is in good agreement with the observation. The results also show that liquefaction and high excess pore water pressure in the foundation has significantly affected the performance of breakwater.
Key words strong earthquake, caisson structure, effective stress analysis, residual deformation, liquefaction.
| Chen Shengli Chen Longzhu |
| (Zhejiang University) |
Abstract Based on the theory of propagation of elastic waves in saturated soil, the dual integral equations describing the vibration of foundation are established. By using the method suggested by the authors, the equations can be transformed into the Fredholm integral equation of the second kind and can be solved numerically. The effects of Rayleigh singular points to the solution of the integral equations are studied in detail.
Key words saturated soil ground, vibration of dynamic foundation, Rayleigh singular point, integral equation.
| Gu Qiangsheng Zhang Xiaoping |
| (Hohai University) |
| Wu Jinquan Sun Youxiang Cai Hongqing Liu Kaihua |
| (Yanchen Bureau of Water Resources, Jiangsu Province) |
Abstract The technique for remedy of fractured concrete structure in water is suggested. A new type of concrete, which will not scatter during poured in water, is developed. The engineering practice shows that thhe technique is effective and feasible.
Key words fractured concrete, remedial technique, in water, non scattered concrete.
| Wu Yongsheng Lian Jijian Zhang Qinghe Qin Chongren |
| (Tianjin University) |
Abstract In this paper,the k-ε turbulent flow model is applied to study the turbulent boundary layer properties under the combined action of wave and current.Numerical analysis results show that the flow motion is not the simple linear superimposition of two actions,but has complicated nonlinear behavior.The presence of wave may exert greater effect on velocity profile than flow current.The comparison of numerical solution and experimental data shows that good agreement is obtained.
Key words k-ε turbulent flow model, combined action, wave, current, boundary layer.
| Niu Zhan |
| (Hydrologic Bureau of YRCC) |
Abstract Based on the classical theory,the evaluation standard and classification of measurement error are established.The formulas for error transfer in measurements of flow discharge,suspended sediment rate and mean concentration in cross section are deduced.
Key words measurement,flow discharge,suspended sediment,measurement error,error evaluation