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EXPERIMENTAL STUDIES ON THE DENSITY CURRENTS IN SETTLING BASINS

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Science in China,Ser.A 1985年第3期28卷 319-336页

作者：范家骅 Institute of water conservancy and Hydroelectric power Research Academia Sinica and Ministry of water Resources and electric power Beijing

On the basis of flume experimental data, analyses were made on the mechanism of the density currents, relevant to the sediment concentration profiles in saline water to form twolayered stratified flows, or in clear water to form backwater density currents in settling *** empirical relations of the settling velocities of sediment particles in moving fluid and the vertical seeping velocities of clear water coming from the density currents were *** on the principle of density current (stratified flow), methods of designing settling basins have been suggested.

关键词： EXPERIMENTAL STUDIES ON THE DENSITY CURRENTS IN SETTLING BASINS

Experimental Research on Shear Behavior of Reinforced Concrete Composite Beams Under Uniformly Distributed Load

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China Ocean Engineering 1998年第4期13卷 467-476页

作者： ZHAO Shunbo Ass. Prof., North China Institute of water conservancy and Hydroelectric power, Zhengzhou 450045, P. R. China. N. China Inst. water Conserv./H.P. Zhengzhou 450045 China

An experimental program was carried out to study the shear behavior of the reinforced concrete composite beam (RCCB) subjected to two-phase uniformly distributed load. A total of 12 reinforced concrete composite beams were tested: 10 of them were the RCCB subjected to two-phase uniformly distributed load, the other 2 were the comparative reinforced concrete beams cast at the same time as the RCCB subjected to one-phase uniformly distributed load. The interface of precast unit and recast concrete was natural and rough. The test range of the main composite factors: the ratio of precast section depth to composite section depth was from 0.35 to 0.65, the ratio of first-phase load moment to precast section ultimate bearing moment was from 0.25 to 0.65. Based on the test results, the stresses of the longitudinal reinforcements and stirrups, the load-bearing properties of the interface, the crack state and the failure characteristics of the RCCB under uniformly distributed load are discussed. The effects of the stirrups, the concrete strength and the composite factors on the shear resistance of the RCCB are analyzed, and the method for evaluating the shear resistance of the RCCB is proposed.

关键词： reinforced concrete composite beam shear resistance composite factor mechanism of failure

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 conservancy 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 20°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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有调压室的水电站水力-调速系统的稳定性

四川大学学报（工程科学版） 2002年第3期34卷 31-33页

作者：徐晶陈明广东水利电力职业技术学院广东广州510635 广东省水利厅广东广州510150

主要讨论引水系统中有调压室的水电站 ,当一根水管向多台机组供水时 ,水电站的水力 -调速系统水力波动的稳定性 ,重点分析多台相同型号的水轮发电机组的运行特点 ,同时考虑到各机组之间的相互影响 ,建立整个动力系统的基本微分方程组 ,... 详细信息

主要讨论引水系统中有调压室的水电站 ,当一根水管向多台机组供水时 ,水电站的水力 -调速系统水力波动的稳定性 ,重点分析多台相同型号的水轮发电机组的运行特点 ,同时考虑到各机组之间的相互影响 ,建立整个动力系统的基本微分方程组 ,通过简化 ,利用罗斯 -霍尔维茨判据理论 ,推导出精确的稳定计算公式 ,并通过工程计算实例加以说明。

关键词：水电站水力-调速系统稳定性调速器动力系统供水总管调压室引水系统

NUMERICAL SIMULATIONS OF THE HYDRAULIC CHARACTERISTICS OF SIDE INLET/OUTLETS

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Journal of Hydrodynamics 2011年第1期23卷 48-54页

作者： YE Fei GAO Xue-ping North China University of water conservancy and electric power Zhengzhou 450011 China School of Civil Engineering Tianjin University Tianjin 300072 China

The hydraulic characteristics at the side inlet/outlet of pumped storage plants is studied by numerical simulations,covering the flow distribution,head loss,vortex,and *** on the physical model test,the realizable k-εturbulence model is used in the 3-D simulation of the side inlet/outlet.A new scheme is suggested to obtain the uneven flow distribution over three branch *** variation of the free surface with the reservoir water level under the pumped condition is simulated,with results consistent with the experimental results.

关键词： hydraulic characteristics side inlet/outlet pumped storage plant numerical simulation realizable k-εturbulence model

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局部网络的控制结构基本概念及BLS

计算机学报 1989年第1期12卷 52-60页

作者：冯龙水电部水利水电科学研究院

本文提出和定义了计算机局部网络的控制结构的基本概念。讨论了它与IEEE 802标准的MAC的区别和联系。认为控制结构和拓扑结构一起,组成了局部网络完整的结构概念,以此本文进一步提出了局部网络的结构分析参考模型,它建议了对局部网络结... 详细信息

本文提出和定义了计算机局部网络的控制结构的基本概念。讨论了它与IEEE 802标准的MAC的区别和联系。认为控制结构和拓扑结构一起,组成了局部网络完整的结构概念,以此本文进一步提出了局部网络的结构分析参考模型,它建议了对局部网络结构进行考察、技术划分、评估的统一方法。本文还提出和定义了局部网通信的位长度系列概念,包括有效位长度、无效位长度、视在位长度和位长度因素,该概念对通信过程进行了抽象和划分,建立了网络性能参数的普遍联系。其中位长度因素反映了通信效率的大小。最后,本文略述了以上新概念的应用之一:建立网络性能分析模型。

关键词：局部网络控制结构计算机

EFFECTS OF WALL ROUGHNESS ON COHERENT STRUCTURE IN TURBULENT SHEAR FLOWS

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Journal of Hydrodynamics 1989年第1期1卷 15-21页

作者： LIANG ZAICHAO LIU SHIHE, Research Institute of water conservancy and Hydraulic power, Wuhan University of Hydraulic and electric Engineering, Wuhan, Hubei, P.R. China

There are many examples that fluid flows on rough wall, such as channel flow in nature, pipe flow, etc. In order to know the flow structure of real fluids, it is important to study the effects of wall roughness on coherent structure in turbulent shear flows. The experiments were carried out in a square glass channel, which is 600cm long, with the cross section of 30×25cm^2. The flow velocity was varied from 2 to 40 cm/s. Uniform sands whose diameters were 0.0012cm, 0.2gcm, 0.385cm, 0.594cm and 0.896cm respectively were glued to the floor of the channel. The rough Reynolds number Re_Δ= U_*Δ/ν=0.04～73, where U_*is the shear velocity, Δ is the diame- ter of uniform sand, v is the kinematic viscosity coefficient. Hydrogen bubble technique for flow visualization and HWL-II hot-film anemometer for velocity mea- surement were used in the experiments.

关键词： EFFECTS OF WALL ROUGHNESS ON COHERENT STRUCTURE IN TURBULENT SHEAR FLOWS Flow

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

EXPERIMENTAL STUDIES ON THE DIFFUSION OF SEDIMENT PARTICLE IN TURBULENT FLUID

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Science in China,Ser.A 1982年第1期 99-112页

作者：范家骅 Research Institute of water Consevancy and Hydroelectric power Academia Sinica Ministry of water conservancy and electric power

Based on the equation of motion of sediment particle settling in turbulent fluid, an ex-pression of vertical diffusion coefficient has been derived under simplified conditions. Thevertieal diffusion coefficient of a fine particle has the same form as derived from the analys’sof Lagrange characteristics of turbulent flow by G. I. Taylor, while the vertical diffusion coef-ficient of coarser particle is a function of the turbulent velocity of the particle,its settlingvelocity and density, and the flow characteristics. Experimental values agree fairly well withthe calculated ones based on the theoretical analysis with an empirical coefficient.

关键词： turbulent settling fairly agree empirical turbulence fluctuating simplified laden settled