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Computer simulation of universal complete pump characteristics
Liu Guanglin
(Wuhan University of Hydraulic and Electric Engineering)
Guo Manhua
(Guangdong Nuclear Power Joint Ventrue Company)
Abstract Based on the experimental Suter
complete pump characteristics of several specific speed,by utilizing the mathematical
model of least square surface fitting of a rectangular region and computer simulation
technology,a new method to predict complete pump characteristics by computer simulation is
proposed.The surface equations,in which relative flow angle x and specific speed n are
independent values,are presented to describe pump complete characteristics in different
region for various specific speed.
Key words pump,complete characteristics,computer simulation.
The
numerical simulation of three-dimensional unsteady flow by operator
splitting and moving boundary method
Li Chong He Shaoling Lu Jikang
(China Institute of Water Resources and Hydropower Research)
Abstract A numerical model of
three-dimensional simulation for large-scale water unsteady flow has been developed.The
model uses the operator splitting method to solve the basic equations for large-scale
water.Moving boundary treatment is applied to complex geography and irregular boundary for
simulating trace of free surface.To test the model,a series of research on single wave in
closed area,wind-induced current,flow in a square lumen and flow in river expansion has
been carried out.The measured data for a sea beach zone and results of some other known
numerical models are in accord with the numerical results.
Key words three-dimension,unsteady flow,numerical simulation,operator splitting
method,moving boundary treatment.
Study on universal software for
calculation of 1-D
unsteady flow in Channel network
Abstract The physical and mathematical
background of the numerical method for one-dimensional unsteady channel flow are discussed
in this paper,including the implicit finite difference equations of the extended St.Venant
equations and Newton-Raphson iterative method,the special equations suitable for special
nodes and iterative equations,the boundary and initial conditions,the assembling of system
matrix and the Gaussian elimination matrix solution techniques with the sparse matrix to
be considered.An example is given to compare with other software.
Key words universal model,channel network,unsteady flow,iterative method.
Analysis of
elastoplastic damage for high jointed slope of the Three
Gorges Project shiplock during unloading due to excavation
Zhang Qiangyong Zhu Weishen Chen
Weizhong
(The institute of Rock and Soil Mechanics,The Chinese Academy of Science S, Wuhan)
Abstract A 3-D elastoplastic
damage constitutive model for intermittent jointed rockmass is established in this
paper.The model is applied to high jointed slope of the Three Gorges Project shiplock to
carry out 3-D non-linear FEM calculation for elastoplastic damage during excavation.Some
useful results and conclusions are obtained
Key words intermittent joints, elastoplastic damage, 3-D FEM.
Preliminary study on the
artificial neural network based
on hydrological property
Yang Rongfu Ding Jing Liu Guodong
(Sichuan Union University)
Abstract This paper presents a
new network named hydologic Modeling Network(HYMN) for simulation of continuous rainfall
runoff.The result of a case study shows that HYMN is practical for use.
Key words Neural network, BP network,hydrologic modeling network.
Estimation of ground water depth distribution by disjunctive Kriging
Qin Yaodong Li BaoguoAbstract Some common used methods
are compared for estimating spatial variability of parameters.The theory and calculation
of the disjunctive Kriging is introduced and an example of estimation of ground water
depth distribution is given.The difference of estimation variances between ordinary
Kriging and disjunctive kriging is discussed.
Key words disjunctive Kriging, ordinary Kriging, inverse distance.
Simulation of storm runoff process for plain urban
Xu Xiangyang
(Hohai University)
Abstract A mathematical model is
developed to simulate hydrologic process in plain urban.It consists of four
sub-models:runoff yield,surface flow concentration,pipe flow concentration and river flow
concentration model.The results of simulating storm flow in the Taipinghu drainage area in
Beijing City are regarded as reliable and reasonable.
Key words storm runoff, simulation, runoff yield,flow concentration.
A new method for field tracing test of groundwater
Ding Jiaping Li zhangshu
(Nanjing Hydraulic Research Intitute)
Abstract A new method for field
tracing test of groundwater dispersion is presented. By using this method the longitudinal
and transverse dispersivities can be obtained simultaneously. The method can well control
groundwater level and flow pattern, increase the gradient of groundwater table in field
test. In addition, the calculation formulas for dispersivities are deduced by solving
simultaneous equations.
Key words longitudinal dispersivity, transverse dispersivity, tracing test, groundwater
pollution.
Analysis and calculation of
the economic loss caused
by water pollution
Liu Cheng Wu Liping
(Pearl River Water Resources Protection Bureau)
Abstract Based upon the reviews
of avaliable model for calculating economic loss caused by water pollution and to cope
with the deficit in calculation, a new model was proposed. The loss of Pearl River basin
due to water pollution in 1993 has been calculated.
Key words value of water resources, water pollution, model economic loss.
Cohesive sediment entrainment from soft muddy bed by waves
Lian Jijian Zhao Zidan
(Tianjing University)
Abstract Considering the
interaction between waves and soft muddy bed, a model for the calculation of wave shear
stress on soft is presented in this paper. On the basis of the calculated results for wave
shear stress, the critical shear stress for the initial entrainment of cohesive sediment
on muddy bed with different densities by waves is investigated by flume tests. A formula
of the critical shear stress for the initial entrainment of cohesive sediment on various
density muddy beds by waves is obtained and compared with the formula of the critical
shear stress of cohesive sediment by currents.
Key words cohesive sediment entrainment, shear stress, soft muddy bed, waves.
An application
of anchoring fracture-damage model to the stability
analysis of the underground chambers
Li Shucai Zhu Weisheng
(Institute of rock and soil mechanics, Chinese Academy of Science)
Abstract Based on the hypothesis
of equivalent strain energy and analysis of the characteristic of stressstrain of anchored
joint plane under the state of compression shear or tension shear stress, the constitutive
relations and damage evolution equation of intermittent jointed rockmass supported with
bolts and cables are established by fracture！damage mechanics method. These relations and equations are
applied to the stability analysis of the surrounding rockmass of the underground chambers.
The results indicate that the characteristics of the anchored jointed rochmass and the
gradual damage law can be better reflected by the model proposed in this paper.
Key words anchored jointed rockmass, fracture-damage model, underground chambers.
Optimum design of
general arrangement of hydraulic hoist for
overflow spillway segment gate
Du Peiwen
(Shandong Provincial Survey and Design Institute of Water Conservancy)
Yang Guangjie
(China International Water an Electric Corporation)
Abstract In this paper, hydraulic hoist
total cost is adopted as objective function for optimization. The optimized design of
general arrangement can be applied to all kinds of arrangement of hydraulic hoist
supported at the end and middle position. It helps oto solve the combined value of
capacity and stroke under the optimum state of hydraulic hoist general arrangement. The
application indicates that the optimum method can greatly reduce project cost.
Key words over flow spillway, segment gate, hydraulic hoist, optimum design, capacity.
A calculating method of
structural reliability for
non-normal random variables
Tang Tieyu
(Shenzhen University)
Abstract An equivalent normal method is
proposed for the calculation of structural reliability. The Concept of this method is easy
to be understood and the calculation precision is approximately the same as that of JC
method. A similar method is also proposed for the case of three variables.
Key words reliability, equivalent normal, reliability index, design point value.
A frequency yield
inverse algorithms for diffuse distribution
coefficient for water quality model
Li Lan
(Wuhan University of Hydraulic and Electric Engineering)
Abstract The characteristic of which water
quality parameter follows the space variation is taken into account in this paper. The
inverse model and algorithms of river water quality longitudinal diffusion distribution
coefficient is developed. To inspect calculation precision, a kind of data transform
formulation is put forward from time yield to frequency yield. Example is given.
Key words water quality model ,distribution, diffusion coefficient, frequency yield
inverse.
The experimental
studies of soil water movement mathematical model
under the condition of partial mulching
Hudan Tumarbay
(Xinjiang Agricultural University)
Abstract Based on the theoretical analysis
and numerical computation, a two dimensional root uptake model which is more suitable for
practical use was obtained. At the same time, by analyzing the experimental data,
relationships between bare soil evaporation, evaporation from mulch strips and atmosphere
evaporation were derived. By observing the physiology index of crop in the field, the
relationship between leaf area index (LAI) and water surface evaporation were also
obtained. The upper boundaries in the corn field can be classified into four categories:
bare soil with shelter from crops, bare soil without shelter from crops, mulch with
shelter from crops and mulch without shelter from crops. The corresponding mathematical
model was presented. The effectiveness of the method presented was tested by soil moisture
data obtained from field. The results indicate that the values of computation agree with
the experimental data fairly well.
Key words partial mulch, bare soil between crops, mulched soil between crops, experimental
studies.
Multi-objective
linear programming method of determining joint
closure temperature field for arch dam
Liu Defu
(Wuhan university of Hydraulic and Electric Engineering)
Abstract This paper establishes a model
for multi-objective linear programming of joint closure temperature field based on the
unit load method for calculating the stress of arch dam. The optimization model was used
to solve the optimal joint closure temperature field of an arch dam with typical southern
China climate condition. The applications show that the model is reasonable and the
optimizing effectiveness is remarkable.
Key words Arch dam,joint closure temperature field, optimization.