• 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

2010 Vol. 21, No. 6

Display Method:
Physically based hydrological model using finite volume methods based on a triangulated irregular network
WANG Lei, TIAN Fu-qiang, HU He-ping
2010, 21(6): 733-741.
Abstract:
The physically based hydrological models are based on the physical descriptions of water movement within the overland,river channel and soil,which makes it promising that the hydrological modeling depends less on the calibration of watershed responses while depends more on the observations and measurements of clmiate and landscape themselves.The spatial discre tization is the very first step in the development of physically based models,and at the same time,it is also the principle way to represent the spatial heterogeneity of landscape properties such as topogra phy,soil,vegetation,etc.The grid based method for spatiald iscretization is one of most commonly used ways for its smiplicity.However,the method cannot represent the heterogeneity in a realistic and efficient manner,and most importantly,the gird based models may not be suitable for the modeling of multiscale hydrological rocesses.In this study,a physically based hydrological model is developed on a triangu lated irregular network(TIN).The model partial different equations(PDEs) derived at micro scales include the Richards equation and Saint Venant equations.The model is resolved numerically using the finite volume method(FVM) that can integrate the PDEs over the controlling space into ordinary differential equations(ODEs).The use of FVM can ensure the balancing of watermass in the numerical solution,as well asmakes it easier when coupling to other ODEs of canopy interception and ground depression.The model is tested over the upper region of the Qin river basin.The results show the reasonable modeling accuracy and efficiency.
Experience and enlightenment from the emergency risk-elimination practice on the Kama reservoir
LIU Ning, HUANG Jin-chi, ZHANG Qi-yi
2010, 21(6): 742-747.
Abstract:
During the flooding season of 2009,the Kama reservoir of Guangxi Autonomous Region experienced an emergency situation.The dam safety risk was at all time high.While emergency actionswere taking place,the state of the dam was studied using the finite-element seepage analysis and the slope stability analysis was also conducted using the nonlinear index approach.The study revealed that the damage position was likely located in the mid portion of the diversion tunnel.Such a diagnostic is particularly desirable in the evolution of damsafety risk assessment and in the subsequent decision making.As the result,proper measures to eliminate the risk were determined,and the risk of dam break was effectively reduced.The experience obtained from the emergency riske lmiination practice on the Kam a reservoir and the associated key techniques can serve as a typical case for addressing the important issues in the management of reservoir safety in China.
Kariz wells in arid land and mountain-front depressed ground reservoir
DENG Ming-jiang
2010, 21(6): 748-756.
Abstract:
An inland river in arid land can be divided into several landform units,including mounta in area,mountain-front alluvial fan,alluvial plain,belt of transition of oasis and desert,and desert and so on.Mountain-front depressed belt around most in land rivers has huge thick gravel aquifer,which is natural ground reservoir with rich ground runoff.When surface water flows through flood alluvial fan,a large quantity of seepage flow from rivers and canals compensates depressed belt of mounta in front ground reservoir.After runoff flows in to plain area of fine soil from the lower ridge of flood alluvial fan,grain of soil gradually becomes fine which forms a natural ground dam of blocking water while ground runoff is over spilled in the form of spring water after it is blocked.Taking the Pilot Project of Ground Reservo ir in Tailan River as an example,the paper proposed detailed idea of construction ground reservoir of Cross section Kariz wells mounta in front depressed belt on the basis of analysis and research on main technical characteristics of Kariz wells and combined with characteristics of landform and land feature,structure of storage water and water resources transformation.It gives prmiarily exploration of structure design principles on followings of its three parts:feasibility of ground reservoir by construction of Cross section Karizwells and its reservoir system of compensation by diversion of seepage flow,its water collected system of Cross section Kariz wells,and water deliverysys tem of artesian siphon.Depressed ground reservoir is ideal for water resources works for emergency to fight the drought.It explores a new model for prompting water resources utilization efficiency and regulation water united surface water with the ground water based on its research and pilot.
Study on the δD and δ18O characteristics of meteoric precipitation during 2006-2008 in Chongqing, China
LI Ting-yong, LI Hong-chun, SHEN Chuan-zhou, YANG Chao-xiu, LI Jun-yun, YI Cheng-cheng, YUAN Dao-xian, WANG Jian-li, XIE Shi-you
2010, 21(6): 757-764.
Abstract:
The stable isotopic compositions of precipitation exhibit great diversities in different areas and seasons due to in fluences of multiple factors,such as temperature,evaporation,rainfall amount,moisture source and others.The Local Meteoric Water Line(LMWL) is established for Chongqing,China using precipitation samples collected between April 2006 and September 2008,as the result of a 29-month field campaign on the campus of Southwest University.Both D and 18O values in rainwater exhibit sign ificant seasonal variations,having higher values in winters and lower one in summers.The result also indicates that the moisture source is the primary factor for determining the isotopic compositions in local precipitation in this monsoonal region.In addtion,the evaporation is another important factor in controlling the isotopic compositions of rainwater during short-term rain events.
A quantitative analysis of climate change impacts on runoff in Naoli River
YAO Yun-long, LÜ Xian-guo, WANG Lei, YU Hong-xian
2010, 21(6): 765-770.
Abstract:
The Sanjiang(three rivers) Plain is situated on the northeastern part of Heilong jiang Province.The plain embraces most concentrated marsh lands and is the largest in China.The Naoli River is a typical marsh river on the Sanjiang Plain; its hydrological regime is largely a ffected by the dual factor of clmiate change and human activities.In this paper,the water balance method and empirical model are used to establish the rainfall runoffre lationship on the Naoli River.Discussions on the advan tages and disadvantages of the two approaches are given.The results show that about 40% of changes in mean annual runoffduring the period 1968 2005 are the results of climate change through the reduction in precipitation for the same period.For example,at Baoqing and Caizuizi stations,43% and 35% decreasing in mean annual runoff can be attributed to the reduction in precipitation,while the evaporation change is only responsible for 10% of such change.Our study also indicate that the water balance method may possess certain advantages over the empirical model,the latter can still be considered to be a quick and easy approach to the subject after all.
Long-term runoff forecasting for autumn flooding seasons in Danjiangkou reservoir based on analyzing the physical causes
LIU Yong, WANG Yin-tang, CHEN Yuan-fang, WANG Zong-zhi, HU Jian, FENG Xiao-chong
2010, 21(6): 771-778.
Abstract:
Amiing at the lack of consideration of using the physical cause approach to forecasting long-term runoff,a BP(Back P ropagation) neural newtork model is developed for autumn season runoff forecasts.The model considers those physical factors affecting the runoff process.The factors include the preceding atmospheric circulation,ocean and historical runoff.Using the principal component analysis,the autumn runoff can be quantitatively related to a set of physical predictors including amtospheric circu lation,sea surface temperature,and antecedent precipitation and runoff.The model is applied to the Dan jiangkou Reservoir.Observed September and October runoff during the period 1956-2000 are used for the model calibration,while observation of 2001-2008 are used for the model validation.The results show that the stability of the model utilizing the physical predictors is generally favorable.On average,a 30% miprovement can be achieved in September and October runoff forecasting comparing to the method of using only antecedent precipitation especially during the drought and flooding years.
Simulation of rainfall infiltration in stony soil
ZHU Yuan-jun, SHAO Ming-an
2010, 21(6): 779-787.
Abstract:
Based on the laboratory rainfall expermients,the process of rainfall infiltration in stony soil is numerically smiulated using the multiple interacting continua(MINC) method.The objective of this study is to further improve our understanding on water movement in stony soil.The results show that the maximum water saturation of soil can be increased if gravels present,while the total amount of infiltrated water and the infiltration depth in soil would be reduced accordingly.There is a steep wet front in the stony soil column,the max mium water saturation of soil decreases sharply along the front surface.The process of rain fall infiltration is well smiu lated by the MINC model.Both smiulated wet front and soil water content close to the observation.The reduction of rainfall in filtration depth in stony soil can be attributed to the change in the maxmium water saturation of soil along the soil profile during a rain fall.
Analysis of irrigation efficiency and water saving potential at different scales
CUI Yuan-lai, TAN Fang, Zheng Chuan-ju
2010, 21(6): 788-794.
Abstract:
Based on a predigested but equivalent canal system for the Zhanghe Irrigation Distric,tusing an empirical formula,the irrigation efficiency(IE) in the system is calcu latedatd ifferent scales under different conditions.The result shows IEs are found to be higher at the primary and trunk canals than that of at the submain and branch canals.These IE differences are mainly due to the differences in the canal cross section and length,as well as the lining ratio.We calculate the maxmium irrigation efficiency(MIE) and its corresponding cost,as well as the water saving potential and ratio underd ifferent conditions.An input output analysis of the relationships between the cost and MIE aswell as the water sav ing ratio is conducted.It shows that bothM IE and the water saving ratio are proportional to the cost,but comply the rule of decreasing rewards during the course of the input output process.The deceleration rate of the water saving ratio would be greater than that of MIE.
Numerical simulation of broken wave with the CLEAR-VOF-FEM model
SUN Ying-wei, CHEN Bing, KANG Hai-gui
2010, 21(6): 795-800.
Abstract:
Based on the unstructured-grid approach,this paper presents a numericalwave flume mode,l in which the Navier-Stokes equation is discretized using the three step finite element method(FEM) and the free flow surface can be captured by the Computational Lagrangian Eulerian. A dvection Remap and the Volume of the Fluid(CLEAR VOF) method.This CLEAR VOF FEM model is used to smiulate the mipinging process by broken wave on the vertical break water built on a mild slope.The result shows that the simulated breaking wave force and flow field are in good agreement with the particle miage velocimetry PIV data,which indicates the applicability of the CLEAR VOF FEM model.
Wave-current interaction effects on velocity profiles and influencing factor analysis
ZHANG Zhuo, SONG Zhi-yao, KONG Jun
2010, 21(6): 801-807.
Abstract:
Many laboratory expermients on wave-current interaction have shown that a reduction in the current intensity is achieved when the wave propagate in the direction of the current,while the opposite is true when the current flowing in the opposite direction of the wave propagation.In this study,the expressions for the boundary shear stress and the velocity profile under the influence of wave-current interaction are derived to expla in the laboratory observed phenomena.The expressions are the Navier-Stokes equation based,which use the small am plitude wave theory as sumption and incorporate with the Grant Madsen model for wave-current bottom boundary layer flow.The result shows that our expressions are able to smiulate the in fluence of wave height and viscosity on velocity profiles,and the smiulation coincides with the observation.Also,our expressions are simple and practical com pared to other wave-current models.Using the expressions,an influencing factor analysis is performed on the laboratory observed phenomena,and the result is presented.
Laboratory study of problems in ice mechanics encountered in the Middle Route of South-to-North Water Transfer Project
XU Guo-bin, LI Da-ran, HUANG Yan, ZHAO Xin
2010, 21(6): 808-815.
Abstract:
Problems in ice mechanics encountered in the Middle Route of South North Water Transfer Project are studied throughice expermients conducted in a low temperature laboratory.The expermients mainly concentrate on the expansive force of the ice,the stability of the ice cover,and the ice force on piers.As the result,a force tmie curve for the change in the expansive force of the ice is obtained,and so does for the change in extremes of the ice expansive force withice thicknesses.The change in ice collapse maxmia is observed for different ice thicknesses as well as for the force time curve for theice force on piers.The change in extremes of the ice force with ice speeds is also meas ured.Our results would contribute to the safe operation of the Middle Route of the South to North Water Tansfer Project in winters.
Turbulent characteristics in open-channel flow with emergent and submerged macrophytes
WANG Cun, WANG Chao
2010, 21(6): 816-822.
Abstract:
Under certain hydrodynamic conditions,different species of aquatic plants will have different impacts on the flow structure and sedmient re-suspension due to the differences in plant morphology.In this study,the sediment collected from the Taihu Lake is placed in a glass tank planting with emergent and submerged macrophytes calam us and water fern.Using the flume expermients,the turbulent flow in the open channel with macrophytes is measured by a three-dmiensional Acoustic Doppler Velocmieter(ADV).The analysis of flow turbulence and sediment re-suspension is conducted.The results show that the vertical velocity distribution has different regularities in open-channel flow with emergent and submerged mcrophytes.Both turbulence intensity and Reynolds Number exhibit obvious anisotropy,and their maximum values are found to be at the junction of submerged plant canopy and at the bifurcation of emergent plant stems and branches,respectively.The sedmient re-suspension process can be inhibited by the presence of emergent and submerged macrophytes under certain conditions.However,when the Reynolds Number reaches a certain value,the presence of these macrophytes can actually exacerbate the sedmient resuspension process.In comparison with emergent plants,submerged mcrophytes would be more effective ininhib iting sedi ent re-suspension.
Numerical simulation of flow-sediment transport on the river-lake in the middle and lower reaches of the Yangtze River
SHI Yong, LUAN Zhen-yu, CHEN Lian-gang, JIN Qiu
2010, 21(6): 823-831.
Abstract:
Using the flood control system in the middle and lower reaches of the Yangtze River as study objects,a numerical model for the smiulation of flow-sedmient transport rates in the rivers and lakes of the reaches is presented.The model is a further development of the numerical flood module that is part of a complex flood control system and able to provide information for flood control planning.A dam module based on hydrodynamics is embedded into the numerical model to forming an integrated modeling system.The latter is used to study the control of flowsed mient transport rates under different planning requirements.In addition,a distribution modeling study of sediment transport through distributed channels is carried out.The integrated system is used to evaluate the flood control plan in the middle and lower reaches of the Yangtze River,as well as to simulate the control branch streng then main stream program in the Dong ting lake region.The result shows that the integrated system is able to effectively address key issues such as assessing the effectiveness of flood control projects and the procedure for optmiizing the projects.Quantitative information can thus be provided by the system for flood control planning.Our results have been used in the planning of flood control projects for the middle and lower reaches of the Yangtze River.
Numerical study of the evolution trend in the river-lake relationship in the middle and lower reaches of the Yangtze River
SHI Yong, LUAN Zhen-yu, CHEN Lian-gang, JIN Qiu
2010, 21(6): 832-839.
Abstract:
Using the flood control system in the middle and lower reaches of the Yangtze River as study objects,a numerical model for the smiulation of flow sedmient transportrates in the rivers and lakes of the reaches is presented.The model is a further development of the numerical flood module that is part of a com plex flood control system and able to provide information for flood control planning.The model is used to studying the control of flow sed mient trans portrates in the rivers and lakes of the reaches under different planning requirements.The numerical study on the in teraction between rivers and lakes is carried.As a result,the evolution trend in the riverlake relationship can thus be established.A miing at the regmie of flow sedmient transport in the rivers and lakes of the reaches,the focus is on the numerical smiulation of river scouring in the Jing Jiang river reach,flow sedmient transport rates in Jing Jiang three estuary,and sedmien tation in the Dongting Lake,as well as the coupling of rivers and lakes.On that basis,the numerical model is miproved to ensure that the numerical treatment of the model is more feasible.The result shows that the modified model is able to effectively smiulate the evolution of flowsed mient transport rates in the rivers and lakes of the reaches.Our results have been used in the planning of flood control projects and flood management practices in the middle reaches of the Yangtze River.
On the real-time evaluation of the storage-discharge relationship in the middle and lower reaches of the Yangtze River
SHI Yong, LUAN Zhen-yu, CHEN Lian-gang, JIN Qiu
2010, 21(6): 840-846.
Abstract:
Using the flood control system in the middle and lower reaches of the Yangtze River as study objects,a numerical model for the real-tmie evaluation of the storage discharge re-lationship in the rivers and lakes of the reaches is presented.The model is a further development of the flowsed mient transport model for the purpose of flood control planning.The model is used to assess the flood prevention schemes for the reaches in this study.To accommodate the needs of quickly and accurately evaluating the storaged ischarge relationship in real-time,we propose an iterative scrolling algorithm and calibration techniques,as well as an expermiental procedure for flood control operation based on hydrodynamics.The real-tmie evaluation objective can thus beachieved.We discuss the coupling between the flood model and the flood control operation model in the context of numerical study of the real time evaluation of the storage discharge relationship in the middle and lower reaches of the Yangtze River.Atrial operation of the numerical model is conducted during the Yangtze River flooding seasons.The result shows that the numerical model is able to effectively address key issues that arise from executing the real-tmie evaluation of the storaged ischarge relationship,and from optmiizing the flood control projects.The result provides the theoretical basis for flood control planning and real-tmie flood operations.Our results have been used in the planning of flood control projects and flood operations for the middle and lower reaches of the Yangtze River.
Real-time flood forecasting in the middle and lower reaches of the Yangtze River
SHI Yong, LUAN Zhen-yu, CHEN Lian-gang, JIN Qiu
2010, 21(6): 847-852.
Abstract:
Using the flood control system in the middle and lower reaches of the Yangtze River as study objects,a numerical model for real-time flood forecasting in the reaches is presented.The model is a further development of the flow and bed load transport module that is part of a complex flood control system and able to provide information for flood control planning.To accommodate the needs of quickly and accurately forecasting floods and operating control structures in real tmie,we propose an iterative scrolling algo rithm and calibration techniques based on hydrodynamics.Coupling the numerical model with real-tmie calibration of hydrological parameters can thus be achieved.A trialoperation of the numerical model is conducted during the Yangtze River flooding seasons.The result shows that the numerical model is able to effectively address key issues that arise from executing the realt mie calibration of hydrological parameters and from realtmie flood forecasting after Yangtze Riverem bankment breached.The result provides the technical support for flood control planning and real-tmie flood operations.Our results have been used in flood operations for the middle and lower reaches of the Yangtze River.
Review of the trends in the study of non-point source nitrogen in hydrological processes on farmland over irrigation district
KONG Li-li, ZHANG Zhan-yu, ZHU Lei
2010, 21(6): 853-860.
Abstract:
The major driving force for non-point source nutrient losses from irrigated farm land comes from the natural rainfall-runoff process in the watershed.Study of the regularity in nutrient losses and the relevant modeling methodologies is thus important for the comprehensive pollution control of non point sourcen itrogen in China's irrigation districts.This paper reviews the trends and progresses in the study of non point source nitrogen in hydrological processes on farm lands,with emphasis on the aspects of the mechanism of nutrient losses and the influence factors,as well as the prediction methods.The scope and application of both black box model and mechanism dissection model are analyzed in detail.The advantage and disadvantage of the two models are also underlined.Based on the study,a prioritylist of promising research areas on the subject is proposed,including the selection of representa tive researchunits,the scale issues,and the coupling of farm land nutrient losses from different hydrologic flow pathways.
Progress in the study of glacial debris flow mechanisms
TIE Yong-bo, LI Zong-liang
2010, 21(6): 861-866.
Abstract:
The glacial debris flow is a widespread geomorphologic phenomenon.Due to the unique characteristics of the flow formation at glacier heads,it would be difficult to conduct a comprehensive control of glacial debris flows.Therefore,effectively forecasting the flow occurrence will provide us with an miportant preventative measure for mitigating the flow disaster.Although,some progresses have been made on the subject in recent years,the development of effective measures for disaster prevention and mitigation has been hampered by the lack of understanding of basic mechanisms that contribute to the formation of glacial debris flows.Recent progresses in the study of glacial debr is flow smechanisms are systemically reviewed,and the current states of the flow mechanism are reported on.Future prospects of research on the subject are put forwarded at last.Our result can provide a scientific basis for the flow mechanism study and the disaster prevention and mitigation.
2010, 21(6): 867-868.
Abstract: