• 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

2005 Vol. 16, No. 5

Display Method:
Formation and characteristics analyses of lateral high concentration convergence zones produced by a pollutant-contained impinging jet in flowing water
FAN Jing-yu, ZHANG Yan, WANG Dao-zeng
2005, 16(5): 623-627.
Abstract:
The characteristics of lateral concentration distribution in a pollutant contained impinging jet in the downstream region related to the stagnation point in flowing water are numericaly investigated in detail using the RNG turbulence model,and compared with the corresponding experimental results. The formation mechanism and diffusion properties of the lateral high-concentration convergence zones in the downstream transition region are analyzed. The computed results indicate that the impingement action and the circumambient cross flow play an important role in the lateral concentration distributions of the impinging jet in the transition region. When the velocity ratio is relatively smal,there exist distinct lateral high-concentration convergence zones both near the symmetry plane and at the lateral edge between the botom layer wall jet and the ambient cross flow,which are dominated by the lateral negative pressure gradient produced by the impingement act ion and the Scarf vortex structure generated by the circumbient cross-flow,respectively.
Research on vortexes of cross flow past a horizontal circular cylinder by PIV system
WU Jian, QI E-rong, LI Wei, HUANG Ming-hai, LI Guo-ya
2005, 16(5): 628-633.
Abstract:
The experimental research on cross flow pasting a circular cylinder near a plane boundary is conducted based on the particle image velocimetry(PIV)system. The experimental principle and devices are introduced. The problems about parameter's selection and particle's tracking are discussed. And the flow characteristics of the upstream of the cylinder are analyzed. Behind the cylinder,the dynamic process of the vortex formation,its development and extinction are displayed on the sub-critical Reynolds number range and gap-ratio is 0.5. The structure of the time-average and instantaneous flow field is compared. Finally,the characteristics of the vortex shedding in the wake are analyzed. Under the given experimental condition,the conclusion is drawn that the Strouhal number keeps the constant of 0.2.
Theoretical analysis of the deflection degree of the flow direction under bevel bridge
LI Fu-jun, ZHANG Bai-zhan, LIN Gui-bin
2005, 16(5): 634-637.
Abstract:
The norm of hydraulic design of railway bridge in China does not consider the effect of the deflect degree of the flow direction under bridge. By extending the calssical fluid mechanism result about the flow field round a pier to two piers,the formula of the deflection degree of flow direcrion is deduced with the assumption that the field around two piers simulates that of one pier. The formula shows that the deflect degree first increases,then decreases,and its maximum increases while the compress rate decreases. The formula fits with the laboratory data well in some condition,and corrects the mistake that the deflect degree only increases while the bevel increases.
Study on the distribution and balance of the salt in the inland basin
DONG Xin-guang, JIANG Hui-fang, DENG Ming-jiang, ZHOU Jin-long
2005, 16(5): 638-642.
Abstract:
In this article,based on the summary of the rsearch conclusion and the systematic analysis of the data of hydrology,soil,irrigation,water and salt,we use the systematic analysis measures,the water-salt movement theory and the water-salt balance principle to analyze and calculate the differ layers'salt distributing and the equation in the basin,the drainage basin, the irrigate region,the cropland and the soil profile.And we analyze,at the different levels of the inland basin,the formation and characteristic of "the salt drainage in the way". We think that "the salt drainage in dry way" is absolutely necessarily. We must consider the different outles and motivations of the "salt drainage in dry way"",so that it can solve effectively the salinization problem in the irrigated regions.
Dynamics of water resources and land use in oases in middle and lower reaches of Shiyang River watershed,Northwest China
LI Xiao-yu, XIAO Du-ning
2005, 16(5): 643-648.
Abstract:
Based on the TM image of the oases in Liangzhou District and Minqin county in middle and lower reaches of Shiyang River in 1986 and 2000,this paper calculates the transformation matrix of the landscape mosaics,and analyzes the relationship between the land use changes and the dynamics of runoff and groundwater resource and their exploitation in the two oases. The results show that:(1)Farmland area expanded distinctly by 6302 hm2 in Liangzhou and 36434 hm2 in Minqin oasis. And the transition of landscape elements in Minqin oasis is developing toward desertification,with the area of 23349 hm2 turned into desert land,however it is also developing toward the other way-the oasis landscape expansion by 81581 hm2 in Liangzhou oasis.(2)The ratio of the utilized water quantity in the upper and middle reaches to that in lower reaches increases great from less than 2 before 1970 to more than 8 since 1995;the annual recharge quantity to the Hongyashan reservoir decreases by 63.1% in recent 40 years.(3)Groundwater exploitation develops progressively,and the density of water-supply wells increases remarkably,up to 5.7 and 1.8 wells/km2 in Liangzhou and Minqin oases respectively in 2000;and the groundwater table drops obviously,the lowering rates reach up to 0.6-0.8m/year in some place.(4)the cropping patterns in the study area are distributed irrationally,too.If the planting percentage of water-wasting crops drops to 50% in both oases, it can save irrigating water by 1.2×108m3 in Liangzhou oasis and 0.2×108m3 in Minqin oasis one year.
Calculation of carrying capacity of eco-environments in Haihe River basins
ZHU Yong-hua, XIA Jun, LIU Su-xia, JIA Shao-feng, FENG Hua-li
2005, 16(5): 649-654.
Abstract:
An interactional optimization model of multi-objectives and multi steps is used to calculate the carrying capacity of eco-environments related to water,and determine the course change of the carrying capacity in the case of the water supply of “South-to-North Water”. Transfer Project,the economical normal development and the graduall amelioration of eco-environments.The results are as follows ①Haihe River basin is now in a serious over loading state of eco-environments.Haihe River basins will not reach a good eco-environmental state and,at the same time,not reach a good social and economical state until 2033.②in 2033,when the eco-environments is in a loadable state,the population wil amout to 157.30 millions,6.30 millions more than the natural increasing population of 151 00 millions and the optimal proportion of water use will be 28%, 43%,18% and 11% in industry,agriculture,ecology and life,respectively.
Study on nitrate-N export changes of the Xijiang River
LIU Ling, HE Guo-qing
2005, 16(5): 655-660.
Abstract:
On the basis of the time series analysis,the changes of nitrate-N concentrations in Gaoyao section of Xijiang River are studied in this paper for the analysis of the integrated catchment's response. It is found that the nitrate-N time series has a linear increase trend. Besides,its peak nitrate-N seasonal index occurs in May,almost the same time as the peak precipitation seasonal index does. It can be concluded that the soil erosion from precipitation,as well as the increase use of nitrogen fertilizer in May are the main cause of the peak nitrate export in the Xijiang catchment. In order to predict the changes of nitrate-N concentration in the Xijiang River,an integrated autoregressive and moving average model of ARIMA(1,0,1)(2,1, 1)12 is developed in this paper. The model's responses are verified by the comparison to the measurements of nitrate-N concentration in Gaoyao station,and a favorable match is found between them. The model simulation is conducted for the prediction of the future nitrate-N export in Xijiang River. It is clear that this paper is beneficial for the water environment protection in the Xijiang catchment.
Investigation on calculation method for flow concentration with stochastic input
SUN Ying-na, RUI Xiao-fang
2005, 16(5): 661-665.
Abstract:
Proving by a lot the measured data,There are many unpredictable and uncontrollable factors in the process of flow concentration. The stochastic differential equation is used to replace the ordinary differential equation to describe the process of the flow concentration more reasonable. The linear random flow concentration system with the white noise input is discussed. The analytic and numerical solution of the flow concentration model can be obtained after the randomness of initial condition is solved.
Recent change of pan evaporation and possible climate factors over the Huang-Huai-Hai watershed,China
GUO Jun, REN Guo-yu
2005, 16(5): 666-672.
Abstract:
The tendency and the possible causes of the pan evaporation change over the Huang-Huai-Hai watershed from 1956 to 2000 are analyzed by using the observed monthly data. The results show a significant decrease in the pan evaporation in the area. The rate of decrease is about -50 mm/10a,and the maximum rate of decrease reaches -80mm/10a over the plain area. It is also found that the maximum decrease of the pan evaporation occurred in the southeast of the Haihe basin and the lower Yellow River during spring,and in the Huaihe basin during summer.The main climatic factors for the change of the pan evaporation are analyzed by studying the relationship between the pan evaporation and such elements as the sunshine duration, the average wind speed,the diurnal temperature range(DTR),the mean maximum and minimum temperature,the mean temperature and the precipitation. It is thus obvious that the decrease of the pan evaporation was mainly caused by the weakening solar radiation and the sunshine duration. The arerage wind speed and the DTR may also play an important role in an unknown mechanism.
Characteristic and variation of groundwater recharge resources in the middle reaches of Heihe River basin
ZHANG Guang-hui, NIE Zhen-long, LIU Shao-yu, CHEN Zong-yu, ZHANG Cui-yun, SHEN Jian-mei, WANG Jin-zhe, CHENG Xu-xue, ZHANG He-sheng
2005, 16(5): 673-678.
Abstract:
Through the invest igat ion and study with the environmental isotopic way and the hydrograph separation method,it is expounded that the rain,the groundwater and the snowmelt from the Qilian mountain area are the main resource to recharge groundwater in the middle reaches of Heihe River basin in the Northwest internal region. The recharge varyies dynamicaly dur ing a year and has its yearly dynamic law.Its relation rate is 0.97 with rainfal,and 0.79 with air temperature at the Qilian station;the relat ion rate is 0.43 with rainfall;and 0.60 with air temperature at the Zhangye station. The rainfal variation in Qilian mountain area is the main factor to the variation of groundwater recharge in the middle reaches,whese in fluence rate is 91% in total rate,air temperature influence rate is 9%.The rainfall and runof are all in abundant state since 1980,so that the decrease of groundwater recharge in the middle reaches of Heihe River basin is closely related with the human activites. Therefore to adjust to the human activity with scientific rules is the key hand to make the groundwater resources sustainable uti lization in conformity with the principle of water cycle in Heihe River basin.
Effect of the anisotropy in porous media on the spatial variability of the hydraulic conductivity
SHI Xiao-qing, WU Ji-chun, YUAN Yong-sheng, JIANG Bei-lei
2005, 16(5): 679-684.
Abstract:
The spatial variability of the hydraulic conductivity in porous media is the base of the groundwater flow and trans-port. To aim at the limitation of the assumption of the isotropy of the hydraulic conductivity got from the geotechnical tests,the measured data in the Borden test are analyzed to illustrate the applicability and the illogicality of the assumption through reduction to absurdity.The effect of the anisotropy on spatial variability of the hydraulic conductivity is also summarized and the principle to determine whether the hydraulic conductivity field is stationary at different field scales is provided in this paper. Finally,some advices on the research of the spatial variability of the hydraulic conductivity are presented.
Impact of sand excavation in Pearl River delta on hydrology and environment
HAN Long-xi, JI Hong, LU Yong-jun, MO Si-ping
2005, 16(5): 685-690.
Abstract:
The river system in the Pearl River delta is the typical tidal network,and influenced by the surface runof and the t ide level of South Sea Since the middle of the 1980s,large scale of sand excavation has resulted in the great changes of the fluvial process and the hydrological conditions. Based on the hydrodynamics features,this paper builds a one-dimensional hydrodynamic mathematical model to simulate the variat ion of water level and flow rate in the tidal river network. By the Grey Model,the riverbed evolution in the future is predicted By using the hydrodynamics numerical model,the impact of the artifi cial sand excavation on hydraulic features,such as water level and flow rate,is respectively analyzed in high flow and low waterperiods Furthermore,the impact of sand excavation on navigation,irrigation,salt intrusion and water environment are preliminarily assessed.
Analysis on scour and deposit variation characteristic of sediment after the operation of Gezhouba hydro project
DAI Hui-chao, HE Wen-she, YUAN Jie, CAO Shu-you
2005, 16(5): 691-695.
Abstract:
The river characteristic and the operation condition of the Gezhouba hydro project are introduced in this paper. The analysis using the measured data shows that the characteristic of the runoff and the sediment discharge after the Gezhouba hydro-project operation is as same as before The variation laws in reservoir area,which are scour and deposit quantity,distribution and the time that achieve dynamic balance of sediment,are studied. These factor variation laws are also studied within below the dam area. The descend reasons,values and vary process of river bed elevation and water level are summarized.This result can provide reference to recognize the reservoir deposit laws when the Three Gorges is operated in conjuntion with the Gezhouba hydro project.
Integrating the hydrological technology for analyzing the base-system of water
LIU Ning, DU Guo-zhi
2005, 16(5): 696-699.
Abstract:
This article describes the concept of base-system of water. It is also considered that the system is frequently adjusted,amended,and evolved. It is great important to correctly estimate its load capability and operational status,as well as to appropriately forecast its trend. For analyzing the base-system of water,the hydrological domain should be objectively extended,the hydrological technology need to be integrated,and fundamental theory researches and hydrological basic work both have to be strengthen.
Comprehensive evaluation on ability of coping with agriculture drought in China
GU Ying, NI Shen-hai, WANG Hui-rong
2005, 16(5): 700-704.
Abstract:
In the article,the afecting factors of ability of coping with agriculture drought(ACAD)in China is analysed,and the evaluation index system of the ACAD is built up. A mathematics clustering method is used to class the ability into three types.It is first time to evaluate the ACAD for 31 provinces in China. The result of the evaluation will be the basic background data for the drought management.
Study on frangibility zoning of agricultural drought in China
NI Shen-hai, GU Ying, WANG Hui-rong
2005, 16(5): 705-709.
Abstract:
According to the water resources characteristics,agriculture suffering drought and forming drought disaster circum-stance and drought-relief ability of water conservancies facilities of the every locality,the principle and index of agricultural drought frangibility zoning are determined,and an analytic hierarchy process model is constructed.A frangibility zoning chart of agriculture drought is drawn in China by applying the software of Map Info6.0. The results show that there are 47 extremely serious frangible regions,104 serious ones,175 general ones,and 14 longitudinal ones,within 340 agricultural drought fran-gibility zonings of countrywide.
Application of the SWAN wave model to Bohai Sea:Improvement of Phillips linear growth term
YANG De-zhou, YIN Bao-shu, XU Yan-qing, WANG Jin, SHA Ri-na
2005, 16(5): 710-714.
Abstract:
The SWAN(Simulating Wave Nearshore)wave model is put into use to examine its applicability in Bohai Sea. By means of the experiments of wind-induced ocean wave,we find that the proportionality coefficient α in linear growth term of wind growth source function plays an important role in the process of wave development and changes along with friction velocity (in default SWAN model,it is a constant). Therefore,based on the experiments,we introduce a new formula of α into the linear growth term of wind growth source function in the SWAN model. We experience with the three processes of wind(two cold waves and a south wind)to validate the improvement in the linear growth term. In conclusion,the results from the improved SWAN wave model agree much better with the measurements than those from the previous the SWAN model. The improved SWAN wave model makes a solid foundation for setting up a proper model of wave numerical forecasting in Bohai Sea.
Analysis and evaluation of water environmental carrying capacity in Three Gorges Reservoir
CHEN Yong-can, LIU Zhao-wei
2005, 16(5): 715-719.
Abstract:
The idea of water environmental carrying capacity(WECC)is put forward to protect water environment from being polluted and maintain the sustainable development of economy and society. Based on the related research work,WECC in the Three Gorges Reservoir(TGR)is investigated and the spatial-temporal distributing of WECC is pictured. The conclusion that the project will reduce the amount of WECC in TGR is made after the study of the influence of TGR on the environment in TGR. This paper not only enhanced the management of the water environment in TGR,but also promotes the further study of WECC.
Index system and fuzzy sets theory for comprehensive evaluation on regulation and storage capacity of underground reservoir
ZHENG De-feng, WANG Ben-de, NIAN Ting-kai
2005, 16(5): 720-725.
Abstract:
The regulation and storage capacity of an underground reservoir is defined with the viewpoint of keeping ecological balance,the sustainable development and utilization of water resources of a watershed. Then the index system of the compre-hensive evaluation on regulation and storage capacity is established. Furthermore,this paper presents a recognition model of fuzzy pattern with cross iteration for multi-objective and multi-layer system to assess the regulation and the storage capacity of an underground reservoir on condition that the index correlation is eliminated. The model can consider qualitative and quantitative indexes and determine the index weights in multi-objective system through combining cross iteration results with the experience and preference of the decision makers. Finally,the model is applied to evaluate and optimize the regulation and storage capacity of the underground reservoirs in the lower watershed of Liaohe river. The case study shows that the new framework and methodology are scientific,reasonable and easy to use in practice.
Comprehensive evaluation of water resource carrying capacity based on fuzzy recognition
LI Ya-wei, CHEN Shou-yu, FU Tie
2005, 16(5): 726-729.
Abstract:
The purpose of this paper is to establisha fuzzy recognit ion(FR)method to solve water carrying capacity evaluation. Based on the data structure of the related indices,the ranking feature value of each region can be obtained through Fuzzy Recognition method,and the evaluation contribution ratio of each index also can be obtained. An evaluat ion case study of 30 regions of China shows the objectivity and practicability of FR.
Spatial-temporal distribution model for the groundwater elevation of dam abutment
ZHENG Dong-jian, WANG Jian
2005, 16(5): 730-734.
Abstract:
Many dams accidents result from its abutment stabilizing failure caused by the high groundwater level. The seepage of the bypass dam is one of the factors to bring about the rise of the abutment groundwater level. As to the decrease the ground-water level of the dam abutment,the seepage proofing curtain of the dam base extends deep into the banks of a reservoir. At the same time,the behavior of the seepage proofing curtain changes with the time. To evaluate the behavior of the seepage proofing curtain and groundwater level of the dam abutment,we analyze the observation data of water table of dam abutment and the influential factor of the groundwater,such as water level of a reservoir,rainfall,temperature,ageing effect and the coordinates of point location.And the expressions of the effect factors of abutment groundwater were developed.Then,based on the observation,the spatial temporal distribution model for the groundwater elevation of the dam abutment is established by the least square method. The abnormal points that have high groundwater elevation are located by comparing the standard deviat ion of the fitting model with the points And the seepage behavior of whole dam abutment is discussed and the weak seepage part of the abutment is located and monitored.
Assessment and optimization model of water resources control alternative for the Yellow River basin
WU Ze-ning, ZUO Qi-ting, DING Da-fa, CUI Meng, CAO Qian, XING Duan-sheng
2005, 16(5): 735-740.
Abstract:
According to the sustainable development request of the economic society,the control objectives of water resources in the Yellow River basin is described. On the basis of this,combing the utilization characteristic of water resources in the YR basin,the index system is put forward,containing the control objective of water resources from two aspects which are the utilization effect of water resources and the sustainable development.Combined with the utility theory,the artificial neural network theory and the ideal-point technique organically,the assessment model for water resources utilization effect of the control alter-native is estoblished.The sustainable development evaluation criterions and quantitative evaluation method are proposed in terms of water resources utilization according to the connotation of the sustainable development.The feasibility of the model and method is confirmed by 8 water resources control alternatives in the Yellow River basin.
A SVM regress forecasting method based on the fuzzy recognition theory
LI Qing-guo, CHEN Shou-yu
2005, 16(5): 741-746.
Abstract:
This paper first introduces the support vector machine(SVM)regression forecasting method into hydrological fore-casting.Further,based on the fuzzy recognition theory proposed by Prof. Chen Shou-yu,a new kind of kernel function of SVM is proposed in the paper. The kernel function has a more reasonable physical significance. At the end,the results of a study case show that the SVM regression hydrological forecasting method and the kernel function of fuzzy pattern recognition is rea-sonable and feasible.
Review of effect of the ecohydrological process on water environment
YAN Deng-hua, HE Yan, WANG Hao, QIN Da-yong, WANG Jian-hua
2005, 16(5): 747-752.
Abstract:
The domestic and foreign current research on the effect of ecohydrological process on water environment includes following topics,namely the development of the ecohydrological process,the ecological water requirement based on the ecohy-drological patterns,the effects of ecohydrological process on the hydrology,water quality and water ecology,and the relative theory,methods and models. However,theses researches can't reveal the ecohydrological process mechanism;furthermore, the studies on the ecohydrology are even weaker. The future topics on the function of ecohydrological on the water environment security regulation are as follows:①the mechanism of development and driving force of ecohydrological;②secondly,the spatial and temporal difference of ecological water requirement based on the ecohydrological process;③the response mechanism of water quality to the ecohydrological process in a basin;④the function of ecohydrological process on the ecological water storage;⑤the regulation on the ecohydrological process in land region near sea for the sea water quality security;⑥the eco-hydrological model based on modern geographical information system techniques;and⑦the ecohydrological decision and management based on the water environment security.
States and advances in monitor of ice thickness change
LI Zhi-jun, HAN Ming, QIN Jian-min, XI Yu-zhu, LU Peng
2005, 16(5): 753-757.
Abstract:
Based on the requirement of the ice thickness change,in the natural science space and time,about the resources and environments of lake,river,sea and glacier ices and in the engineering science,the structures safe operation of the ice infested waters in winter,the advantages,the drawbacks and the favorable situations of the ice thickness measurements with the modern techniques are summarized.The obtained data lack the long time monitoring,and their accurate cannot reach the stndard,mm,so these data cannot support the set-up or modification of the forecast model forice mass balance in different environments. Therefore some new techniques for ice thickness changes are developed. They are direct contacing equipment for interfaces in an ice sheet,and the rulers for measuring air,ice and water's electric conductivity. These methods can obtain the higher accuracy the ice and snow's freezing and melting processes.This paper gives their work principle,the research advances,the useful case of ice conditions and the preliminary results from the practice in the ice of the polar sea and inland rivers.
Serial discontinuity concept and its development status in river ecosystem research
ZHANG Shui-long, FENG Ping
2005, 16(5): 758-762.
Abstract:
The paper systematically reviews the development of the serial discontinuity concept(SDC)and its application. The river continuum concept influences the development of the SDC and its original form. The SDC evolves into two kinds of forms,the original form and the extending one With its extending form the discontinuity in whole river corridor caused by river regulation can be predicted. As the theoretical base of modeling and analyzing the river re-regulating planning,the SDC can provide guideline for the new project programs of watersheds and the restoration of the regulated rivers However,there are a few research works about the serial discontinuity concept in China. It is suggested to strengthen the research of this field in or der to improve the restoration of river ecosystem.