• 全国中文核心期刊
  • 中国科技核心期刊
  • 美国工程索引(EI)收录期刊

2002 Vol. 13, No. 6

Display Method:
Numerical simulation of 2-D shallow-water flow on irregular grids
CHEN Zu-hua, LAI Guan-wen, WANG Guang-qian, WANG Zhi-shi
2002, 13(6): 657-664.
Abstract:
A numerical model for solving the 2-D shallow-water flow on irregular grids is described. The model based on finite-wlume method adopts the Roe's approximate Riemann solver to deal with the advection terms in the shallow-water equations. A bilinear approximation for the topography in a discrete cell is introduced to preclude the restrictions on the Roe's scheme duo to bed slope. And a modified MUSQ, technique is combined to obtain an increased accuracy. Instead of unilateral difference method,the least square method is used to find the gradient of the primitive variables so that irregular grids can be used. The results of several examples show that the model is capable of treating discontinuities and flow transients,and is good accuracy as well as performance for different applications.
Planar 2-D flow and sediment mathematical modeling
ZHANG Xi-bing, YIN Rui-lan
2002, 13(6): 665-669.
Abstract:
Based on triangular grids,the planar 2-D flow and sediment mathematical model is established by the finite element method Since the mass concentration and the pre-estimated and verified iteration are used to solve the equations,the questions of memory units and calculation velocity are settled quite well Simulation calculation is carried out on the cavity recirculation and single-sudden-expansion channel The results show that flow field and sediment distribution are simulated successfuly in the model and the calculations are stable,fast and accurate
Transverse turbulent dispersion coefficient in straight channel
ZHENG Xu-rong, DENG Zhi-qiang, SHEN Ji-hong
2002, 13(6): 670-674.
Abstract:
Based on the relationship between the vertical turbulent dispersion coefficient and hydraulic geometric shape,the distribution of local water depth with transverse surface in straight channel is put forward. The distribution of transverse turbulent dispersion coefficient and it's expression of average value are determined. The cross-section averaged transverse turbulent dispersion coefficient is found to be in good agreement with the of experimental data of 138 sets. The transverse turbulent dispersion coefficient calculated by using the equation are close to the observed. It indicates that the equation is not only nxme reasonable and clear in terms of theory and mechanism but has also the lowest error than others.
Large eddy simulation of flow through francis turbine runner
ZHANG Chang-bing, YANG Yong-quan, JU Xiao-ming, GUI Lin
2002, 13(6): 675-681.
Abstract:
A large eddy simulation(LES)approach based on the weakly compressible hydrodynamic equation for the relative motion is developed in a rotational coordinate system,and employed in simulating 3-D flow through a francis turbine runner.The finite volume approach with predictor corrector method and a law of the wall for the solid wall condition are used.The velocity and pressure fields are obtained and compared with the computated results by the k-ε model,showing that the 3-D LES approach can give realistic results of the flow field.
Some theoretical studies on the Muskingum method and its successive routing in subreaches
RUI Xiao-fang
2002, 13(6): 682-688.
Abstract:
The physical meaning of parameter X in the Muskingum method(M-method)is given by the hydraulics principle and the flood wave movement theory The storage equation of M-method is showed to be approximately the dynamic equation of difusion wave and the routing equation of M-method satisfied some conditions are proved to be two order accuracy solution of the diffusion wave equation Applicable condition and necessity of successive routing in subreaches of the M-method are suggested A equation of successive routing in subreaches of the M-method is derived by the Z transform method.
Fuzzy recognition dynamic programming model for complex system decisions
CHEN Shou-yu, FU Guang-tao, WANG Jian-ming
2002, 13(6): 689-695.
Abstract:
This paper develops a fuzzy recognition dynamic programming model for hybrid multiobjective multistage decision making problems arising from complex systems A fuzzy aggregation operator is first de rived from a fuzzy pattern recognition model to get a global evaluation for all objectives Then,by incorporating the operator into the traditional dynamic programming,two dynamic approaches are proposed to solve the problems,i e,the minimum ranking approach and the stage recognition approach,which form the fuzzy recognition dynamic programming model The two approaches are of characterist ics of different back re currence equations A nonstructural decision analysis method is simultaneously used to compute the objective weights in the dynamic process of decision makings Finally,a case study is given to show the model is rea sonable and feasible in practice.
Node-weighted core and hierarchical structure of water resource system
LUO Qiang, SONG Chao-hong, LEI Sheng-long
2002, 13(6): 696-700.
Abstract:
The sketch network,which is often used in water resource system to simplify the studied problems,is seldom used for system analysis.In fact,knowledge related to the sketch network could be used to analysis the system deeply,which is common used in social system and communication system.In this paper, the concepts of the node-weighted core degree and the node-weighted core are introduced into water resource system.According to experts' knowledge,we can weight the elements of the system,that is,the nodes of the sketch network,and then measure the importance of elements of system from the sides of function and structure.Therefore,the core engineering of system can be founded.Based on these concepts,the hierarchical structure of system is studied,and an algorithm calculating the hierarchical structure is given here.
2002, 13(6): 700-700.
Abstract:
FVS scheme in 2-D depth-averaged flow-pollutants modeling
ZHAO Di-hua, YAO Qi, JIANG Yan, YANG Jue, PANG Yong
2002, 13(6): 701-706.
Abstract:
Developed in the framework of the finite volume method,the flux vector splitting(FVS)scheme is employed for flow-pollutants simulation.Upon integrating the governing differential equations over an arbitrary cell and using the rotational invariance property of the flux,a 2-D problem is transferred into solving a series of local 1-D problem.The numerical normal flux of variables across the interface between cells is estimated by the FVS scheme.Two applications are used to examine the scheme capabilities.Simulated results match the exact solutions very well.The comparison between computed results and observations in Jiangsu Reach of Yangtze River demonstrates good agreement.
Water quality synthetic forecast model for sea outfall
WANG Xiang-san, LI Chong-rong
2002, 13(6): 707-713.
Abstract:
This paper introduces a 3-D synthetic model for simulating the diffusion of warm sewage pollution sources at weakly mixing sea outfall. This model considers the vertical velocity,the vertical gradient of flow field,the vertical temperature gradient and heat exchange of the region around sewage outfall. A multilayer 2-D model is used for the region for away from sewage outfall,which considers the velocity gradient and temperature gradient for every layer. The calculated results agree with the observative data.
Influence of the water transfer project from south to north(middle route) on algalbloom in Hanjiang River
DOU Ming, XIE Ping, XIA Jun, ZHANG Wan-shun, HOU Bing-liang
2002, 13(6): 714-718.
Abstract:
The basic reasons of algalbloom occurrence in middle and lower reaches of Hanjiang River are terrible pollution of water in lower reaches,sun light and rising water temperature in spring,and the slow velocity of flow in Hanjiang River as the result of low water in Hanjiang River as well as relatively high water level in Yangtze River.A hydrodynamics model and eutrophication model are established,providing pollution load maintains the status quo.By sampling in each aggregate of environmental factor which conduces toal-galbloom,the probability of algalbloom occurrence around transfering water are calculated by using the models.The result indicates that the probability will be increased after transferring 14.15 billion m3 water from Hanjiang River,but decreased after finishing of the water transfer project from Yangtze River to Hanjiang River.
Salinization and improvement ways of water quality of Tarim River, Xinjiang, China
FAN Zi-li, MA Ying-jie, ZHANG Hui, DU Li
2002, 13(6): 719-725.
Abstract:
The stream water of Tarim River was fresh before 1958,and its mineralized degree was below 1.0 g/L at all the river sections and at all seasons.However,the average monthly mineralized degree of the water at all the river sections are over 1.0 g/L in the whole year except the flood season in August.At Aral Hydrometric Station at the upper reaches of Tarim River,the monthly mineralized degree of the water is 1 to 3 g/L,3 to 5 g/L and over 5 g/L for 5,4,and 2 months respectively every year,and the highest value comes to 6.3 g/L in May.The proportion of fresh water at Aral is lower than 35% of the annual runoff volume.The stream water at Kara at the lower reaches is totally sub-salt water1 The main causes resulting in the high mineralization of the stream water of Tarim River are the irrational irrigation and drainage,increase of the water consumption for irrigation at the upper reaches,which decrease in the annual fresh water volume of the mainstream of Tarim River from 5 billion m3 before 1960 to 4.2 billion m3 after 1990,except the effects of natural factors,such as arid climate,great evaporation,and high salt content in soil.Meanwhile, large amounts of the drained water from farmlands is discharged into Tarim River,brought the salt of 4.674 million t into the river every year.In order to improve the stream water quality of Tarim River,it is suggested to reduce the volume of the drained water from farmlands,separate the salt water and fresh water,with-drew from farming to reforesting and grass-planting,properly exploit groundwater in the areas of the three tributaries so as to maintain an annual discharged water volume of 4.6 billion m3/a to the mainstream from those tributaries of Tarim River.
Soil water and salt balance model for irrigation district in arid and inland region
HU An-yan, GAO Jin, HE Yi, YU Yan-feng
2002, 13(6): 726-729.
Abstract:
To study on water-salt transport regulation in the arid and inland region,it is benefit for rational utilizing water resources,reducing no-effective phreatic water evaporation,preventing saline-alkali soil.According to the principle of water balance and salt balance,the paper develops a soil water and salt balance model to study soil water-salt transport regulation in the arid and inland region.The accuracy of the model depends on the accuracies of the precipitation,evaporation,irrigation water,salt,etc.
New definition and computation on the water sensitive index in Jensen model
CONG Zhen-tao, ZHOU Zhi-wei, LEI Zhi-dong
2002, 13(6): 730-735.
Abstract:
In the past research,the water sensitive indexes greatly depend on the partition of the growing stages. To solve the problem,the Jensen model is rebuilt and the water sensitive index is redefined. A terse new method computing the water sensitive index is introduced according as the water sensitive indexes are able to accumulate. The practical field experiment validates that the new method is well consistent with the old those.
Dynamic production function model for crop yield in response to water and nitrogen
WANG Kang, SHEN Rong-kai, WANG Fu-qing
2002, 13(6): 736-740.
Abstract:
A dynamic model for crop dry matter production response to daily available soil water and nitro gen was presented.Field experiments were carried out at Yongledian water saving station,Beijing.Using in formation of accumulative dry mater of winter wheat with full supply of water and nitrogen,we estimated the function of winter wheat to soil water and nitrogen based on the experimental data.With the simulated model parameters we calculated the dry mater production under various irrigation and nitrogen conditions.Good agreements between simulated and measured dry mater accumulation process were obtained.
2-D numerical simulation for the process of water infiltration and pore gas expelling
MA Guo-tao, SHAO Long-tan, CONG Long-fei, FENG En-min
2002, 13(6): 741-746.
Abstract:
The equations with coupled boundary condition on the interface,which govern the process of pressured water infiltration and pore gas expelling in unsaturated soils,are established in this paper based on the equilibrium analysis for pore water and pore gas separately. It presents a new method to solve the problems of water infiltration. Examples of applying the method to 2-D numerical simulation of the process of pressured water infiltration in dry sand and fly ash are given. The results of the simulation show the influence of pose gas expelling on the water infiltration process. Comparisons of numerical simulation by the method and theoretical solution for one-dimensional problems are illustrated. It shows that the proposed method is accurate.
On the fractal dimensions characters and trend of drought in China
ZHU Xiao-hua, YANG Xiu-chun
2002, 13(6): 747-750.
Abstract:
According to the fractal theory,the fractal character of drought in China is preliminarily discussed in this paper,and the trend of drought in China is discussed too.Some conclusions are drawn as fol lows:(1)The fractal dimensions character of drought exists in China,and the fractal dimension of drought in Huabei is 0.8784,that of Dongbei is 0.8167,and that of Huanan is 0.8428,etc(2)The fractal dimensions of different level drought in different regions in China are calculated,and the relat ionships between the whole fractal dimensions and the average fractal dimensions for different level drought in different regions are discussed too(3)The trend of drought in China is also opened out,thus,if we continue the unsustainable policy,the drought may not be controlled in someday in China.
On the dimensions of Qinhuai river networks based on the GIS technology
WANG Qian, ZOU Xin-qing, ZHU Da-kui
2002, 13(6): 751-756.
Abstract:
The river networks is a kind of natural fractal. This article discusses mainly how to get the dimension of a river network by counting the boxes which covers the river networks in the mean while by changing the side of the boxes. All of these are based on the MapInfo and MapBasic which can program the computer to do the job instead of manual operation and can get much rare comprehensive information of the dimension of the river networks. By this way,the article points out that the fractal dimension of network is related not only to the development phase of the river but also to the system of physiognomy,land use and so on.
Effect of land use on ecological water requirement of river basin
FENG Hua-li, WANG Chao, ZHU Guang-can
2002, 13(6): 757-762.
Abstract:
The interruption of human with the ecosystem of a river basin will change the land use dramatically such as reducing the seasonal flood area,losing the natural wetland,decreasing the diversity of habitat and biology and so on.Based on the holistic theory of river basin,the biodiversity theory,the patience theory and the landscape ecology theory,the influences of various land uses on ecological water requirement are analyzed.The results prove that the ripatian natural plant ecosystem can allocate the water quantity,improve the water quality of river basin,lower the risk of a river basin threatened by the shortage of water resources, and ensure the ecological water requirement on longer time and wider space scales.So the reasonable measures about land uses including protecting wetland,ripatian forest and island water ecotone should be taken in order to make the ecosystem sustainable development of a river basin.
2002, 13(6): 762-762.
Abstract:
Method of town distribution in resettlement of affected residents for flood control and safety construction and its application
YUAN Ru-hua
2002, 13(6): 763-767.
Abstract:
To counter the characteristics of less utilization frequency and long prediction period of the flood storage and detent ion basin,the method of optimal town distribution in the reset lement of affected residents plan is presented by using the regional distribut ion theory and considering the industry and agriculture devel opment,the natural and geographical features and relocates' production and living conditions under the premise of utilizing the flood storage and detention basin rationally and effectively. This method is applied to the embankment area plan of Hongzehu Lake.
Analysis of water saving in received area in Huanghe-Huaihe-Haihe watersheds and Eastern and Middle Lines of Water Transferring Project from South to North, China
SHEN Fu-xin, GENG Lei-hua, QIN Fu-xing, XU Peng-bo
2002, 13(6): 768-774.
Abstract:
The principal goal of the transferring water projects from south to north China is to supply water requirement of cities. Most of the water supply is for industry utilizat ion that is approximately 65.6 percent of city water utilization in the received area. Therefore,it is very important to analyze industry water saving in the received areas.This paper emphasizes on analyzing industry water utilization and present situation,potential capacity,investment and benefit of water saving in Huanghe-Huaihe-Haihe watersheds and the eastern and middle lines of the projects.The results indicate that industry water saving in the received areas is better than that of the other areas in China.The industry water saving should be focused on the present industries in cities and agricultural areas.However,increase of industry water utilization could not be satisfied by water saving solely.
Review of methods for deriving physical descriptors of the watershed topography from DEM
XIONG Li-hua, GUO Sheng-lian, Kieran M. O' Connor
2002, 13(6): 775-780.
Abstract:
Some widely used physical descriptors of the watershed topography,such as slope gradient,the flow allocation coefficient,the specific contributing area,the contributing area,and the wetness index,are described and discussed in the context of the DF1VI-based distributed hydrological modeling. Fmstly,the methods for deriving these physical descriptors of the watershed topography from DFM are reviewed in detail. Then,according to its definition,each physical descriptor is interpreted with the focus on the corresponding hydrological meaning in relation to the water rmvements in watersheds. Finally,based on the DF1VI information required for calculating these physical descriptors,the ability of each physical descriptor to represent the effect of the watershed topography on the spatial distribution of hydrological response to rainfall in water-sheds is explored and a hierarchical structure of these physical descriptors is proposed. Thus,the review of these physical descriptors of the watershed topography will be very useful to enhance understanding of the mechanisms of runoff generation in watersheds,to explore the temporal and spatial distribution of hydrological processes,and to study the DFM-based distributed hydrological ridels.
Study on soil erosion experiment, monitoring and modeling of various scale conditions
TANG Zheng-hong, CAI Qiang-guo, XU Feng, ZHU Yuan-da
2002, 13(6): 781-787.
Abstract:
It is the important methods for obtaining the data of soil erosion through soil erosion experiment and monitoring.The soil erosion models are the important contents for soil and water conservation planning, management.This paper summarizes the results of soil erosion experiments and monitoring studies,introduces the key points of experiment and monitoring,and reviews and evaluates the current major soil erosion models of overseas,especially in analyzing the effects of these models on the condition of global climate change.
2002, 13(6): 788-788.
Abstract: