• 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

2009 Vol. 20, No. 4

Display Method:
Study on watershed hydrologic processes using TRMM satellite precipitation radar products
YANG Chuan-guo, YU Zhong-bo, LIN Zhao-hui, HAO Zhen-chun, WANG Zhen-long, LI Min
2009, 20(4): 461-466.
Abstract:
The objective of this study focuses on the application of the TRMM(Tropical Rainfall Measuring Mission)satellite precipitation radar data in the simulation of the land surface hydrologic processes and the evaluation of its performance in hydrologic simulation and forecast. The quality of the TRMM 3B42 rainfall data is validated with the gauged rainfall data in a 32 year period. Forced by the gauged and TRMM 3B42 rainfall data,two continuous hydrologic simulation cases are conducted to analyze the temporal variability and the spatial distribution of the hydrologic process in Huaihe River basin from 1998 to 2003. The analyses show that the TRMM rainfall is comparable to the gauged rainfall data in the hydrologic study. The simulated streamflow hydrograph with the TRMM rainfall is also consistent with the observed one at Bengbu station. Results indicate that the satellite radar rainfall has a promising prospect in the study of the land surface hydrologic processes.
Role of run-on process of overland flow on hydrological modeling
LIU Jin-tao, LIANG Zhong-min
2009, 20(4): 467-472.
Abstract:
In this paper,a grid-based kinematic wave Xinanjiang model is developed and the structure of the original Xinanjiang model is downscaled and modified accordingly. The basin is subdivided into raster network. The raster slope and flow vectors are extracted by the software package,DigitalHydro based on DEM.The Xinanjiang model is used for calculating runoff in each raster and the kinematic wave method is used for overland flow routing. In each grid,water input to the model includes precipitation and runoff from the upstream grids to take runoff infiltration(i.e. run-on mechanism)into account in runoff calculation module. In the kinematic wave model,the Manning coefficients are determined according to the land cover information and the flood grade. The Huangnizhuang sub-basin with an area of 805 km2 in Shiguanhe basin,Huaihe River is selected as the studied area. It is shown that the run-on mechanism has an important effect on the runoff prediction and it also affects the spatio-temporal distribution of the soil water storage. The results show that the predicted flood peak without consideration of the run-on mechanism will be lagged.
Depression removal method for grid DEM based on three-direction search
LI Hui, CHEN Xiao-ling, ZHANG Li-hua, LI Chang-an
2009, 20(4): 473-479.
Abstract:
The Digital Elevation Model(DEM)is the fundamental data source to extract the watershed parameters. However, the depressions and flat areas commonly exist due to the errors in the production of DEM. Various methods are thus proposed to remove the depressions and flat area in DEM. Most of the methods assume that the depressions are caused mainly by the underestimation of DEM values. In fact,the overestimation can also cause the depressions in the nearby grid cells. In this paper, a new method based on three-direction search is presented to handle the problems by both raising and reducing the DEM values. The result suggests that the proposed method is easy to implement and can eliminate the "parallel river" in the result,and makes less modification of the original DEM values only to keep the original information to the largest extent.
Lattice Boltzmann simulation of particle settling and experimental validation by PIV
ZHANG Jin-feng, ZHANG Qing-he, LU zhao
2009, 20(4): 480-484.
Abstract:
To investigate the behavior of the particle-laid turbulent flows,a numerical model is presented through the lattice Boltzmann(LB)method with the large eddy simulation. The simulated settling velocity of the spherical particle agrees with the theoretical value and the measured result by the particle imaging velocimetry(PIV). Furthermore,the flow field around particles and the flow velocity in the tail are illustrated. The computed results are basically in accordance with the measured values. It verifies that the LB method and the large eddy simulation can be applied to simulating the particle-laid turbulent flows.
Experimental study of the velocity profile at 90° open channel confluence
LIU Tong-huan, GUO Wei, ZHAN Lei
2009, 20(4): 485-489.
Abstract:
Based on a large group of the flume experiments and the 3D Acoustic Doppler Velocimeter(ADV),we research the variation of the surface slope and the distribution characteristics of the average velocity around the 90° junction zone with different discharge ratios. And the result shows that the jacking action of the main and the tributary flow has some effect on the surface slope of the upstream of the entrance;the surface slope of entrance and the mixing area of the confluence along the down-stream increases with the rising of the discharge of the main stream,and decreases with the rising of the discharge ratio;the vertical distribution of the averaged velocity of different notes are doubly influenced by the discharge ratio and the flow pattern, to be exact,the average velocity of the upstream of the entrance decreases gradually with the increase of the discharge ratio, while the high and low velocity zone emerges obviously and the separation zone is formed along downstream of the entrance.
3D numerical simulation of free surface flow on tri-prism grids
WANG Kun, JIN Sheng, MA Zhi-qiang, GAO Shu-feng
2009, 20(4): 490-494.
Abstract:
In order to simulate the free surface flow problem,a 3D Navier-Stokes equation based on the tri-prism grid is established,which has the hydrodynamic pressure model and the semi-implicit numerical discrete format. At the outflow boundary,we add the linear attenuation terms of sponge layer processing to the right-hand of the momentum equations to reduce the wave energy.We use the k-ε turbulent equation to solve the eddy viscosity coefficient in order to close the model. The numerical tests include the simulation of regular period wave propagation over a bar and the compound open channel situation. While tackling the short-wave high frequency problem,we found that the results are in good agreement with the analytic solutions or the measured values,which shows the accuracy and validity of this model.
Appliance of oxygen and hydrogen isotope in the process of precipitation infiltration in the shallow groundwater areas of North China Plain
WANG Shi-qin, SONG Xian-fang, XIAO Guo-qiang, WANG Zhi-min, LIU Xin, WANG Peng
2009, 20(4): 495-501.
Abstract:
In the shallow groundwater areas of North China Plain water cycle mostly occurs as infiltration,evaporation and evapotranspiration in the vertical direction,in which the unsaturated zone plays an important role in precipitation and groundwater. Isotope can be used to trace the process when the precipitation infiltrates and recharges groundwater. In this paper Cangzhou and Hengshui sites are selected as the typical shallow groundwater areas to research the difference of the infiltration process under the different precipitation features,soil textures and vegetation conditions. The results show that at the site with the heterogeneous soil texture the precipitation infiltrates and moves in soil as the piston mode and the mixture effect,and the evapotranspiration effect during the infiltration process is significant in the distribution of soil water. Some evidence is provided for the existence of the preferable flow at 100 m depth. The groundwater is mainly recharged by precipitation1 However,at the homogeneous site the infiltration process is uniform and the soil water moves as piston mode,too. Both deep soil water and groundwater are totally recharged by precipitation. After precipitation the recharged groundwater experiences strong evaporation effect.
Experimental study of the air entrapment effects on soil structure and infiltration
LIANG Ai-min, SHAO Long-tan
2009, 20(4): 502-506.
Abstract:
The theoretical analysis and experiments are conducted to study the effects of the entrapped air on the soil structure and infiltration. We apply the 2.8 cm ponding depth at the soil surface to two the antecedent water contents and three porosities soil columns and measure the air pressure ahead of the wet front,the cumulative infiltration,and the change of soil structure. The theoretical and experimental results indicate that the air pressure can lift the saturated layer of soil near the surface to cause an upward disruption in the soil column in the wet front before the air pressure head reaches the air-breaking value.The disruption makes the bottom layer discontinuous with the top layer. The data from the infiltration experiments generally indicate that the structure changes of the infiltration soil are affected by the antecedent structure and water contents. For the consolidated and high water content materials,the change of the structure and air pressure is smaller,vice versa. In addition, the disruption lifts the soil in the surface and,in some cases,stops infiltration.
Evaluation on efficient utilization of generalized water resources
PEI Yuan-sheng, ZHao Yong, ZHANG Jin-ping, QIN Chang-hai
2009, 20(4): 507-512.
Abstract:
The evaluation of the efficient utilization of the generalized water resources is to assess the water resources at regional/basin scale. The evaluation based on the simulation of water resources cycle reveals the hydraulic relationship among the regions,industries and sectors,whose water resources are generalized water resources,the evaluation objects are the natural ecosystem and artificial ecosystem,and the evaluation indexes include efficiency and benefit of the generalized water resources in different industries,sectors and regions. The paper divides water consumers into the high efficiency parts and low efficiency ones according to the different evapotranspiration,puts forward the generalized water resources evaluation index which includes the different users,sectors and regions of natural and artificial ecosystem,and takes Ningxia plain as the case study to evaluate the current efficient utilization of the generalized water resources in Ningxia plain.
Water resources allocation model based on the dual-control of water quantity and quality
LIU Bing-jun, CHEN Xiao-hong, JIANG Tao
2009, 20(4): 513-517.
Abstract:
The practice of water resources allocation constantly advances in these days. Accordingly,the concept,connotation,principles and methods of the water resources allocation are gradually enriched. All these facilitate the solution to the coexisting problems of the seasonal,development-induced and quality-induced water shortage in wet areas of Dongjiang Baisn1 Hence,Focused upon the quantity of water intake and pollutant discharge in low-flow period,this paper makes the first attempt to propose a water resources allocation model based on the dual-control of water quantity and quality which may serve as the theoretical and practical reference to the scientific management and the allocation of water resources in water-rich areas in South China. The investigations of the relevant principles,indexes and methods are also involved in the study of the model.
Intelligent integrated model for forewarning evaluation of watershed water security
WU Kai-ya, JIN Ju-liang, WEI Yi-ming
2009, 20(4): 518-525.
Abstract:
In the paper,the accelerating genetic algorithm based on the fuzzy analytic hierarchy process is used to filtrate the index system and determine the weights of both the indexes and the subsystems of the water security forewarning evaluation system,the back-propagation neural networks updating model is used to predict the values of the evaluation indexes,and the set pair analysis method is used to determine the relative membership degree function values of the variable fuzzy set of the assessed samples according the criterion grades of watershed water security,and the intelligent methods integrated forewarning evaluation model(IMI-FEM)is established for the watershed water security. The results of IMI-FEM applied to evaluating the water security system of Chaohu watershed in the following future five years show that the security states of its water resource security sub-system,water environment sub-system and water disaster sub-system are 2.73~2.74,3.30~3.32,and 2.54~3.43 grade respectively,the security state of its society&economy subsystem is 3.33 grade,the whole state of the watershed water security system is 2.98~3.20 grade in the critical security state,and the restrict indexes of Chaohu watershed water security system are as follows:the water resource utilization ratio,the water resource amount of per person,the water resource amount of unit area,the water resource demand amount of per ten-thousand Yuans of agriculture production value,the fertilizer wastage of unit area,the water resource demand rate of eco-environment,the environment protection investment of unit GDP,storage capacity of water conservancy projections of unit area,the water conservancy projection investment of unit GDP, the regional exploitation exponent,the population density,and the science&technology investment of unit GDP.
Analysis of the variety and impact factors of dissolved oxygen downstream of Three Gorges Dam after the impoundment
CHEN Yong-can, FU Jian, LIU Zhao-wei, CHENG Xiang-ju, ZHU De-jun
2009, 20(4): 526-530.
Abstract:
The variety and impact factors of the dissolved oxygen(DO)concentration and saturation at the two sections,up-stream or downstream,of the Three Gorges Project dam after the impoundment are analyzed based on the field data. The results reveal that,since a great deal of oxygen dissolves into water due to the air entrainment when water sluices through the orifices, the phenomenon of DO super-saturation is observed in the downstream of the dam. However,DO concentration(saturation)in the downstream hardly varies if water sluices through the electricity power stations. When water sluices through the electricity power stations and orifices synchronously,DO concentration(saturation)of the downstream is mainly affected by the ratio of the two discharges. Additionally,the downstream water level also has an impact on the downstream DO concentration. When the total discharge is more than 35 000 m3/s and the downstream water level is higher than 68m,or when most of the discharge sluices through the orifices,great attention must be paid to the effect of DO super-saturation on the aquatic.
Simulation of nitrogen and phosphorus loss in sloping field
WANG Jian-zhong, LIU Ling, SONG Lan-lan
2009, 20(4): 531-536.
Abstract:
An event-oriented,nitrogen(N)and phosphorus(P)transport model is developed to simulate the N and P transfer processes in farmland slope during the rainfall period. The Green-Ampt infiltration equation modified and the kinematic wave equation are used to estimate the infiltration volume and the overland flow.The soil erosion is computed with the revised Euro-pean soil erosion model. N and P transfer from soil to overland flow is simulated with the model including erosion driven pro-cesses and diffusion process. N and P transport within the soil profile is described by the 1D advection-diffusion equation. The model calibration and validation are performed with the measured data derived from the indoor artificial precipitation experiment,and the results show that the model can be used to simulate the N and P concentration in overland flow effectively,and the efficiency coefficients during calibration period and validation period are both above 0.89. The relationship between rainfall intensity,slope and N,P concentration in overland flow are analyzed.
Experimental study of the effects of Na+ on the desorption of soluble matters in rivers
XU Wen-sheng, CHEN Li, ZHAO De-zhao, LIU Xin-tong
2009, 20(4): 537-543.
Abstract:
Taking the total desorption quantity of Ca2+ and pH of the equilibrium desorption solution as the representative indexes to evaluate the desorption of soluble matters,this paper primarily investigates the effect of Na+ on the desorption of soluble matters,based on the static state experiments. The results indicate that,with respect to the same sediment and particle size,the total desorption quantity of soluble matters increases with the increment of initial Na+ concentration of the desorption solution,and gradually reaches a maximum amount. With the same sediment but different particle size or in the same particle size but different sediment,the total desorption quantity of soluble matters is of great difference from the same initial Na+ con-centration. For the same initial Na+ concentration with different soluble matters,the variation of the total desorption quantity with sediment components or particle size is also different. With the same sediment,particle size and initial Na+ concentration,the desorption process has a good concomitance with different soluble matters.
Analytic method for pollutant mixing zone in rivers
WU Zhou-hu, JIA Hong-yu
2009, 20(4): 544-548.
Abstract:
On the basis of the theoretical solution to the concentration distribution under the conditions of the invariableness continuous plumb line source in the straight width rectangle of the river, this paper discusses the analytic method of the pollutant mixing zone in rivers, and deduces the largest length of the pollution mixing zone, the largest width and its corresponding formula of longitudinal coordinate, the area and the largest allowable pollutant load. The example analysis of the pollutant mixing zone is conducted. The result indicates that the analytic method can be used for the analytic gist of the outfall's pollutant mixing zone in the allowable range and the largest allowable pollutant load, and the theoretical calculation is faster, more flexible, more convenient and more practicable than the 2D water quality model used for the calculation of the pollutant mixing zone. The paper gives the largest length calculation formula of the non-conservative substances pollutant mixing zone and the condition, neglecting the reaction and the decay effect and dealing with it based on the conservative substance. The formula of the decay number (De) is as follows: De≤0.027.
Model for coupling diffusion of volatile poisons in water and air
CHEN Li-ping, JIANG Jun-cheng, HAN Dong-mei
2009, 20(4): 549-553.
Abstract:
The spill of the volatile poisons into natural waters causes water pollution and air pollution arises from the volatilization of water pollution. In order to explain the coupling of water pollution and air pollution, the dynamical model is put forward by using the volume of fluid method, in which there is gas-liquid interface flow term. According to the double-film theory explaining the volatilization, the dimensionless Henry constant of the volatile poisons is used to establish the coupling diffusional model in which the transport of the volatile poisons in water and air and mass transfer across gas-liquid interface are presented together. The spill of the volatile poison into the Mississippi River and a gas-water experiment are simulated. The simulation results are in exactly agreement with those of the experiment. The simulation analyzes the influence of the turbulence of water, wind velocity and the dimensionless Henry constant on the mass transfer across gas-liquid interface.
Ecological operation goals for Three Gorges Reservoir
GUO Wen-xian, XIA Zi-qiang, WANG Yuan-kun, HAN Shuai
2009, 20(4): 554-559.
Abstract:
The research on the reservoir ecological operation is a hotspot problem in the current river ecological restoration research. On the basis of the actual situation of Three Gorges Reservoir (TGR), the ecological problems of current reservoir operation schemes are pointed out. Taking Yichang hydrological station in the downstream of TGR as a case, the ecological operation goals of TGR are studied from mainly maintaining the environmental flow of natural rivers and protecting the spawning and reproduction of two species fish of Chinese Sturgeon and four major Chinese carps. The study has an important meaning for maintaining the healthy river ecosystem, and the results provide the reference for making the reasonable reservoir operation schemes after the completion of Three Gorges Project.
Ecological water requirements in the lower reaches of Luanhe Basin
WANG Wei, YANG Xiao-hua, WANG Yin-tang
2009, 20(4): 560-565.
Abstract:
Based on the methods of the ecological water requirements (EWRs) at home and abroad, this paper takes the area from Panjiakou reservoir to Luanhe estuary of Luanhe Basin as the typical area to determine the water allocations of the river ecological restoration in reservoirs' downstream. EWRs are calculated with the month-by-month frequency method and eco-hydraulics method. The methods can describe EWRs according to seasons and grades, meanwhile emphasize the relationship between hydrology and ecology. Through the analysis of the ecological, hydrological and hydraulic data from the studied area from 1956 to 2000, the results indicate that: (1) The month-by-month frequency method and eco-hydraulics method are both reasonable in calculating EWRs in the Lower reaches of Luanhe Basin; (2) The minimum, medium and ideal level of annual EWRs are 4.29×108,8.93×108 and 16.29×108m3, about 10.18%, 21.21% and 38.68% of the natural river discharge respectively; And (3) the ratio of the monthly ecological flows should be 33.5% in the flood period (August) and 11.5% in the biological propagation period in spring (April-June).
Co-evolutionary study on the ecological environment and the social economy multiplexed system
MA Xiang-dong, SUN Jin-hua, HU Zhen-yun
2009, 20(4): 566-571.
Abstract:
Through the system analysis of water resources restraint, the ecological environment and the social economy multiplexed system's competition and cooperation, this article uses the synergetics theory as a foundation to establish the multiplexed system's degree of order models and the multiplexed system's coordination evolution model, which produces the corresponding computational method. The paper analyzes the model correspondingly and points out that the multiplexed system's coordination evolution is divided into three kinds of situations in the different states: the part competition substitution, the part competition coexistence and the completely independent coexistence. Finally, based on the General Bureau of Heilongjiang State Farm's ecological environment and the social economy multiplexed system's statistical data from 1986 to 2006, the paper establishes the corresponding coordination evolution model and carries on the analytic computation, the result is basically consistent with the reality.
Mechanism of transverse-crack formation during river-ice breakup
MAO Ze-yu, ZHAO Xue-feng, HU Ying-jun, LIU Ying
2009, 20(4): 572-577.
Abstract:
During the river-ice breakup, the longitudinal cracks near banks are firstly formed due to the runoff increase, resulting in the detachment of central part of ice cover from both banks.Subsequently, as a result of horizontal bending or vertical bending of ice cover the transverse cracks will be further formed, and the continuous icE-cover is finally fractured into floes with cerain sizes.Based upon the theory and calculation method of elastic-foundation, the mechanism of transversE-crack formation is fully investigated.By means of studying on the bending moment and bending stresses of ice cover, the analytical expressions of the crack-spacing due to both horizontal bending and vertical bending are presented, and validated with the field measurements.The study indicates that the transversE-crack spacing depends on the icE-cover width, thickness, bending strength and topography.
Floodwater resources utilization based on flood forecast information of reservoir operation chart
LIU Zhao, HUANG Wen-zheng, HUANG Qiang, ZHANG Yong-yong
2009, 20(4): 578-583.
Abstract:
To improve the floodwater resources utilization by the reservoir operation and the researching reservoir flood regulation method considering rainfall and runoff forecast information, an operation chart for reservoir flood control is put forward by using 3-hour flood forecast information on the basis of analyzing flood course and reservoir flood control characteristics. Furthermore, taking Ankang reservoir for example, the optimum computation is carried and the operation chart is studied for the purpose of floodwater resources utilization by combining the improved genetic algorithm with the flood routing simulation. By comparing its application with the conventional flood control scheme, the result indicates that the former has apparent advantages in flood peak cutting and water storage at the end of flood regulation, which proves the validity and the advantage of the optimized operation chart.
Distributed simulation of hydrological response to water and soil conservation measures
HE Chang-gao, DONG Zeng-chuan, SHI Jing-yuan, CHEN Weibin
2009, 20(4): 584-589.
Abstract:
The original Topmodel is modified properly and the soil and water conservation topography index conception is given to simulate the hydrological response to water and soil conservation measures. At the same time, the vegetation index is used to take into account the difference of the vegetation canopy interception. The modified model is calibrated with five years daily rainfall and runoff records (1992~1997). The daily runoff data is used to simulate the five situations, that is, the original state, the states with the terrace measure, the grass measure, the fruit forestry measure and the water and soil conservation forest measure in the upstream of Qingjiang station in Xiuhe basin, the modified model gives a sound result.
Advances in assessment indicators of irrigation water use efficiency
CUI Yuan-lai, XIONG Jia
2009, 20(4): 590-598.
Abstract:
The definitions and their utlization about the assessment indicators of the irrigation water use efficiency (IWUE) are reviewed. The disadvantages and their use conditions of the existing IWUE are analyzed. We conclude that no indicators can be used to quantify IWUE in any conditions. Firstly, the connotations of different nomenclature of IWUE are ambiguity, which results in the use interchangeably of various terms regardless of the precise implications of their recommendations. Secondly, some new concepts of assessment framework and indicators are right, but it is difficult to determine the components in the framework, and thus not suitable for the utilization in water management in an irrigation system. Finally, we point out the essentiality of giving the precise implications of the existing IWUEs and their specific use conditions, investigate their relationships and affecting factors, and propose the methodology of evaluating the water saving potiential.
Review of gravitational erosion researches in the middle reach of Yellow River
XUE Hai, WANG Guang-qian, LI Tie-jian
2009, 20(4): 599-606.
Abstract: