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    15 June 2018, Issue 6
      
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  • China Rural Water and Hydropower. 2018, (6):  1-5. 
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    Soil evaporation is a key trait in determining water consumption research of agriculture in sparse crops or in early period of the growing stages in maize and winter wheat. After measuring soil evaporation using the micro-lysimeter with different material and size in the maize and winter wheat field, we analyze the seasonal variation of soil evaporation and its variance among different micro-lysimeter material and sizes. Results showed that the seasonal maximum of soil evaporation is 6.0 and 4.6 mm/d for the maize and winter wheat, which occurs in sunny days after precipitation or irrigation when the leaf area index was small in the beginning or maturing periods. The measurements of soil evaporation using different material micro-lysimeter have no significant difference in maize field, while the large diameter micro-lysimeters measure the soil evaporation higher than the small ones. However, the different size of micro-lysimeter has no effect on the measurement of the soil evaporation in the winter wheat field. Finally, we suggest that using the micro-lysimeter with 125 mm diameter for the outer barrel in steel or plastic, 118-114 mm diameter for the inner barrel in steel in the survey of soil evaporation in Nanjing area.
  • CHEN Lei 1,2 ,QIAO Chang-lu1,2 ,HE Xin-lin1,2 ,WANG Yan1,2
    China Rural Water and Hydropower. 2018, (6):  6-11. 
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    In order to explore the effect of drip irrigation under oatmeal on evapotranspiration in oasis,the effect of evapotranspiration and cotton drip irrigation on cotton growth is analyzed through continuous monitoring of evapotranspiration in sub-drip irrigation. The results show that under drip irrigation conditions,the evapotranspiration intensity at seedling stage is 2.84 mm/d; the evapotranspiration intensity at bud stage is 4.48 mm/d; the evapotranspiration intensity at flower-boll stage is 4.89 mm/d; the evapotranspiration intensity at boll-opening stage is 3.61 mm/d. The total evapotranspiration is 397.54 mm,the total evapotranspiration without coating is 542.02 mm,and the film evaporation was reduced by 26. 65%. Under the condition of film mulching,the growth index of cotton is better than that of non -film mulching. Comprehensive analysis: Compared with no films,drip irrigation under mulch can reduce the evapotranspiration intensity and promote cotton growth in oasis area. The results can provide a theoretical basis for determining the irrigation system of drip irrigation cotton under oasis in Xinjiang oasis.
  • China Rural Water and Hydropower. 2018, (6):  12-17. 
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    In order to evaluate the effect of different tillage methods on soil moisture of maize accurately, the research monitored the soil moisture during the whole growth period under conventional tillage with returning straw and subsoiling with returning straw in real time and analyzed the dynamic changes of soil moisture at different time scales. The results indicated :(1) Subsoiling could increase the soil water content of 10cm, 30cm and 70cm respectively by 7.66%, 8.74% and 6.37%.The soil moisture of 30 cm soil layer under the two tillage methods showed a big difference. (2) At hourly scale, it was found that the variation of each layer soil water content of two tillage methods was quite different after raining. When the soil moisture reached its peak after rain , the soil water content of 10cm during the conventional tillage would dip at night, and that during the subsoiling tillage would gradually decline during one day.(3) In addition to the seedling stage, the subsoiling could significantly improve the soil moisture of other growth stages of which jointing and filling stage to enhance the most,respectively at 5.00% and 6.03%.(4)Compared with conventional tillage,subsoiling could increase yield 5.70%.
  • WU Ping1,2 ,MENG Zhao-rui 1,2 ,WU Li 3 ,ZHANG Yan-hui 4 ,BA Rui-shou1,2 ,QI Ze-xue1,2
    China Rural Water and Hydropower. 2018, (6):  18-21. 
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    Based on the daily meteorological data of Xining meteorological stations from 1970 to 2016,by using Hargreaves-Samani method, McCloud method and 1948 penman method with the Penman-Monteith method as the standard of calculating reference crop evapotranspiration (ET0), attempt to estimate applicability of the three methods in Xining region. The results show: 1948 penman method and the Hargreaves-Samani method is superior to McCloud; the result of McCloud estimating is significantly smaller; Hargreaves-Samani method has the same calculating values with the Penman-Monteith in small ET0, and estimates significantly higher than the standard value in high ET0; the correlation coefficient between 1948 penman method and Penman-Monteith method is high, and its has the best consistency ,the estimate value of Penman-Monteith equation can be instead of 1948 penman method by Multipling a constant approximately,improving the accuracy of estimation.
  • QIAO Shuai-shuai 1,2,3 ,HU Zhen-hua1 ,WEI Zheng2,3 ,ZHANG Bao-zhong2,3
    China Rural Water and Hydropower. 2018, (6):  22-26. 
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    In order to study the applicability of DNDC model to winter wheat in typical crops of North China Plains,the DNDC model is used to simulate and verify the wheat growth under different irrigation regimes and the accuracy of the model is evaluated. Based on the measured data of winter wheat growth period in 2015 and 2016,the DNDC model of winter wheat under different irrigation regimes is established,the sensitivity of different parameters is analyzed to soil moisture,biomass and yield during the growth of winter wheat. The DNDC Model parameters are also calibrated and verified,and the accuracy of the model is evaluated in this study. The results show that,crop water demands are more sensitive to yield and above ground biomass. Under the different irrigation systems,the all evaluation indexes between the measured value and the simulated value of soil moisture,above ground biomass and yield during the growth period of winter wheat were within acceptable range. DNDC model can simulate the soil moisture,above ground biomass and yield of winter wheat during growth period in North China better,which is of guiding significance to the production of winter wheat.
  • China Rural Water and Hydropower. 2018, (6):  27-32. 
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    This study estimates the virtual water flows embodied in agricultural commodity trade among Chinese provinces on the base of input-output analysis combining the Chinese interregional input-output table and agricultural water consumption information. After the estimation, the intensity of virtual water flow (the proportions about virtual water outflow and inflow against local water resources) and scale of virtual water inflow (the proportion about virtual water inflow against total water flow within local area) are setup to reflect the trade frequency of products having high virtual water content and the importance of virtual water flow, respectively. The future fluctuations of every province are calculated using the precipitation and temperature output data from Beijing Climate Center Climate System Model in different climate change scenarios. The fluctuations are then used to estimate the variations about virtual water flows and relevant evaluation indexes. Results show that the virtual water flow intensity’s variations of the provinces with high intensity are much bigger than other administrative regions under climate change. It is also found that the virtual water flow have both positive and negative effects on the distribution of water resources, and the climate change has very small influence on the situation that most of the virtual water flowing in the developed areas come from water scare regions.
  • HUANG Jing-guang1,2,3 ,WU Wei 1,2 ,CHENG Lu-yao1 ,YU Nan1,3 ,CHEN Bo1,3
    China Rural Water and Hydropower. 2018, (6):  33-39. 
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    As an important prerequisite for reservoir operation and power generation, the prediction accuracy of river runoff has a direct impact on the comprehensive benefits of water conservancy projects. Based on the historical data of runoff, this paper proposes a wavelet analysis support vector machine (SVM) feature classification combined forecasting model for its volatility and randomness. Firstly, the wavelet decomposition is used to extract the high and low frequency energy spectrum of the original runoff sequence as the SVM sample mark, and the original sequence is classified by feature, dividing into stationary and abrupt sequences, the wavelet approximation signals and the detail signals, corresponding to different types of sequences, are predicted by auto-regressive moving average model (ARMA) and BP neural network model respectively, then the prediction results of each sequence are reconstructed. Finally, the Mean Absolute Percentage Error (MAPE), the Root Mean Square Error (RMSE) and the Theil Inequality Coefficient (TIC) are used as the evaluation indexes of the model. The results show that: under the 3 evaluation indexes, the proposed model is better than the ARMA and BP neural network models, and it has better prediction stability.
  • SU Hui-dong1,2 ,JIA Yang-wen2 ,NI Guang-heng1 ,GONG Jia-guo2 , CAO Xue-jian1 ,ZHANG Ming-xi 1 ,NIU Cun-wen2 ,ZHANG Di 2
    China Rural Water and Hydropower. 2018, (6):  40-43. 
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    Machine learning has a wide range of applications in various fields and interdisciplinary subjects. In this paper,two machine learning methods,support vector regression SVR and BP neural networks,are used to learn,train and predict daily runoff based on the daily precipitation and runoff data of 2009 - 2014 in Yangtze River Basin. To compare with the traditional distributed hydrological model( THREW) ,The Ns efficiency coefficient and percent bais PB are adopted as indicators. The results show that the THREW model,with clear physical process and hydrological mechanism,has good simulation effect and the Ns coefficient efficiency is 0.503. However,the PB is big, and the data and the operation is complex. The two machine learning methods work better in relative error index,and all have good runoff prediction and generalization ability. That is the ability to apply learning outcomes to new knowledge. But they are more dependent on data, and the larger the data sample size is,the prediction results will be fitter. The prediction of runoff results by BP neural networks performs well in index,but it is distorted in the prediction of maximum runoff. The simulation results showe that the BP neural network is superior to the THREW model while the THREW model is better than the SVR simulation results.
  • QIU Bao-rui 1,2 ,SANG Xue-feng2 ,ZHOU Zu-hao2 ,LIU Jun3
    China Rural Water and Hydropower. 2018, (6):  44-48. 
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    With the development of global warming and rapid urbanization,the torrential floods have been frequent in recent years. According to the maximum daily rainfall data of Ezhou in 1959 and 2016,the worst for calculating rainfall in Ezhou City by Pearson III distribution method to determine Ezhou in 20 years,50 years and 100 years of rainfall,through the analysis of Liangzi Lake in Ezhou and Yaerhu and other medium-sized lakes in different return periods of its peak and flood storage effect,found in Liangzi Lake for 20 years,50 years,100 year flood storage of water were 3.29,3.73 and 4.04 billion m3 respectively,in lake water storage capacity of 87%,83% and 80%,on Yaerhu on 20 or 50 years,the 100 year flood storage of water were 0.39,0.22 and 0.23 million m3,respectively,in lake water storage capacity of 35%,32% and 30%,compared with Ezhou City flood control and drainage standard and discuss the countermeasures of flood control in Ezhou.
  • TAN Jing,ZHANG Yong-xiang,ZHANG Da-sheng
    China Rural Water and Hydropower. 2018, (6):  49-51. 
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    Hydrogeological parameters are important parameters in numerical simulation of groundwater. it is retrieved by pumping experiments for simultaneous interpretation of these parameters, and the problem of hydro-geological parameters identification is actually a complex nonlinear program. Precision of many traditional count methods is low by human factors. A combined algorithm which combines the good global searching ability of artificial fish swarm algorithm with the strong local optimization ability of simulated annealing in this paper. The result of case analysis shows that the combined algorithm than the traditional method are more reliable and more accurate calculation, and the calculation value by the combined algorithm accords with the actual value. Compared with the artificial fish swarm algorithm, the combined algorithm can run shorter, higher computational efficiency, it is a simple and effective method to calculate aquifer parameters.
  • ZHANG Chun-hui 1 ,WANG Bing-liang1,2
    China Rural Water and Hydropower. 2018, (6):  52-57. 
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    To explore the runoff simulation effect of the SWAT model driven by CAMDS dataset and traditional meteorological station data in the arid area where meteorological data is insufficient, the two SWAT models based on the datasets mentioned above were built separately with them being calibrated and verified under the support of the measured monthly runoff data from the hydrological station. The results showed that over the period of calibration (2008-2012), Nash-Suttcliffe efficiency coefficients of the two types of model were 0.846 and 0.642 separately, and the coefficient of determination were 0.741 and0.597; In the verification stage from (2013-2016), the Nash-Suttcliffe efficiency coefficients were 0.816 and 0.619 with coefficients of determination being 0.752 and0.628 respectively. The simulation effect uncovered that the model moved by the CMADS data is more reliable than that supported by traditional meteorological data, indicating that CMADS can provide basic data and accuracy guarantee in construction of the SWAT model in the arid basin lacking meteorological data.
  • WU Su-juan,WANG Shuang-yin,NIU Chen
    China Rural Water and Hydropower. 2018, (6):  58-62. 
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    Studying the rainstorm formula can provide a scientific basis for design flood calculation, flood control and town drainage in small watershed, and is of great significance to urban planning and basin ecological environment construction. Based on the observed rainfall data of 18 major meteorological stations in Shaanxi province from 1984 to 2013, five short-duration rainstorm series (10min, 30min, 60min, 90min and 120min) were selected by the annual maximum sampling method, and then the four parameters rainstorm formulas were calculated with the Levenberg-Marquardt Method based on the whole series and the P <50% semi-series of the empirical frequency points and the whole series and the P <50% semi-series fitted by the P-Ⅲcurve respectively. The accuracy of the parameters was analyzed and the regional laws of the rainstorm formula parameters of were studied. The results show that: (1) The precision of rainstorm formula calculated based on empirical frequency points are higher than that of P-Ⅲ curve; (2) The accuracy of rainstorm formula based on P <50% semi-series is higher than that of the full series;(3) It is the most effective way to calculate the rainstorm formula parameters based on P <50% semi-series of empirical frequency points. (4) There is a significant linear correlation between the rainstorm formula parameters and the latitude, longitude and elevation of the station in the north of Qinling Mountains.
  • HOU Li-na
    China Rural Water and Hydropower. 2018, (6):  63-67. 
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    Jinsha River is the important hydropower base of west China, and also the important water resources area for some water diversion project such as the water diversion for central area of Yunnan. Climate change is gradually changing the global water cycle status, and also impact the hydrological regime of Jinsha River. This study use RS hydrological model to simulate the hydrological process of Jinsha River basin, and set up the climate change scenarios based on the emission scenarios of IPCC’s 5th assessment report and GCM scenarios, in order to analysis the influence of climate change on Jinsha River main stream runoff in future. The results show that, in the future, the runoff of Jinsha River main stream will be increase, but the annual distribution of runoff will be more uneven; the runoff in flood season will increase and in non-flood season will decrease; in addition, the flow of Q10 will be increase and of Q90 will be decrease. The all results above will bring new challenges to the water resources application of Jinsha River main stream.
  • ZHAO Cui-ping GONG Jia-guo,WANG Hao ,WANG Ying ,YANG Miao
    China Rural Water and Hydropower. 2018, (6):  68-71. 
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    : In the Huangshui Basin,the distribution of land use type and vegetation coverage can be acquired based on the spatial analysis technology of ERDAS and ArcGIS software,using LANDSAT8 TM and MODSI remote sensing image. According to the technical criterion for ecosystem status evaluation,through calculating biological richness index,vegetation coverage index,water network denseness index,land stress index and pollution load index,the feature of ecological environment is evaluated and analyzed. The results indicate that the ecological environment of Huangshui Basin is overall general level,mainly owing to the low ecological index of urban area of Xining County and Minhe County. Other County kept in good level about ecological index. Intensifying water resources management and controlling of the water pollution discharge is the key of the ecological environment governance at this stage.
  • XU Zhen1 ,ZHAO Jin-yong2 ,LI Qing-guo1 ,DONG Ya-nan1
    China Rural Water and Hydropower. 2018, (6):  79-83. 
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    Based on the habitat preference method,the River 2D model is used to simulate the habitat of fish in Yufu River,according to the number of fish habitat ( WUA) and benthic integrity on the Yufu River recharge program comprehensive analysis. The result shows that taking the program of discharging the flow at Wohushan Reservoir to 2 m3 /s,it is predicted that more than 50% of the optimal channel will be restored to most of the 104 national highway. considering the diversion status of the South-to-North Water Diversion Project,the discharge flow rate of 4 m3 /s is adopted,which will allow all the Yufu River reach through and the ecosystem will recover to the upper middle level. The study serves as a reference for the ecological restoration of typical seasonal rivers which supply water from reservoirs in North China.
  • CAO Wen-han1 ,ZHANG Qiang1 ,LUO Xiao-qin2 ,SHI Xiao1 ,LI Hong-ye1
    China Rural Water and Hydropower. 2018, (6):  84-87. 
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    In order to study the spatial distribution of Nitrate concentration in drinking water sources of residents near an airport, the points of 24 residents were analyzed. The results showed that the correlation coefficient between magnesium and Nitrate was the highest, and the correlation coefficient was 0.726, but the significant P value could not be provided. The correlation between the two variables was tested by Partial process, and the correlation coefficient was 0.787, P = 0.001. The correlation between the two is very strong, and the concentration of magnesium ions can be used as a covariate for the interpolation of collaborative Kriging. When Kriging interpolation is used, the standard mean and standard root mean square prediction error of the cooperative Kriging model are both excellent. By kriging interpolation and then you can get the prediction of nitrate concentration in the study area Distribution, look forward to provide some guidance to the local water pollution control.
  • China Rural Water and Hydropower. 2018, (6):  88-91. 
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    To explore the feasibility of the coagulation-dissolved air flotation(DAF)-filtration process in the advanced wastewater treatment, a pilot study on the coagulation- dissolved air flotation-filtration advanced treatment process was carried out in a sewage treatment plant of Wuhan with the effluent from the secondary sedimentation tank of A2O process as raw water. The experiment completed the three factors and three levels orthogonal experiment of reflux ratio、dosage of coagulant、surface load three factors, COD、TP、turbidity removal rate as the evaluation index, the results showed that the dosage had the most significant effect on the removal of COD, total phosphorus and turbidity. The optimum operating parameters of the recommended process were surface load of 11.11m3/m2?h, dosage of 10mg/L and reflux ratio of 12%. Under this operating conditions, the unit water treatment power consumption and drug consumption for a total of 0.039yuan/m3; At the same time, the continuous flow test was carried out under the condition of fixed surface load of 10m3/m2?h. The results showed that under a certain water quality fluctuation condition, the process was reliable, the treatment effect was stable, the effluent COD concentration was stable below 15mg/L, The concentration is stable below 0.1mg/L, the turbidity of the effluent is less than 0.5 NTU, which has certain engineering application prospect.
  • China Rural Water and Hydropower. 2018, (6):  92-96. 
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    Canna indica, Typha orientalis and Zizania aquatica were experimentally cultivated in semi-simulated sewage through artificial water distribution according to the characteristics of nitrogen and phosphorus in these three kinds of wastewater. The adaptability of tested plants to these three types of wastewater, as well as the purification efficiencies of tested plants against nitrogen and phosphorus, were studied. Results showed that survive and growth characteristics of tested plants, total nitrogen and ammonia nitrogen removal efficiencies were not significantly (P>0.05) different among three types of wastewater in either farmland return water or village farmland mixed water. Total phosphorus removal efficiencies of Z. aquatica was highest among three plants. However, C. indica and T. orientalis could survive but Z. aquatica dead in village ditch water. Moreover, biomass of C. indica was significantly higher than that of T. orientalis in this wastewater (112.5 g/plant and 80.04 g/plant, repectively). In addition, the change curves of total nitrogen removal efficiencies over time among three tested plants were significantly different in village ditch water. The average total nitrogen removal rate in C. indica group was the highest at 57.09%, and then T. orientalis at 46.38% at the end of experiments. The lowest removal rate was found in the treatment of Z. aquatica and was at 19.11%. Considering total removed volume, and plant growth, the efficiency of applying plants in agricultural non-point source pollution of Fen river watershed, C. indica and Z. aquatica could be used for wetland plant configuration as the optimal plants within the limits of concentration range of nitrogen and phosphorus.
  • China Rural Water and Hydropower. 2018, (6):  97-101. 
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    To explore the optimal preparing method of modified carbon for absorbing phosphate in water, the biochar was prepared from reed straw, then the biochar was modified using ultrasonic co-precipitation. The results showed that the phosphate adsorption property of biochar reached optimum level when it was mixed with the solution of zirconium oxychloride and ferric chloride. It has been demonstrated that using ratio of zirconium to iron of 1: 1 and total concentration of zirconium to 0.03mol/L to modify biochar is the optimum condition. The pH of the solution has a relatively large effect on the phosphate adsorption property of biochar. The adsorption capacity decreases as the solution pH increases. At the initial phosphorus concentration of 10mg/L and the dose of 0.8g/L, removal efficiency of ZrFeCl3-BC for phosphate was more than 90%, and the residual phosphorus concentration reached Grade B emission standard of "Discharge standard of pollutants for municipal waste water". The anions in the solution also had a definite effect on the uptake of phosphate with the order of influence being HCO3-> NO3-> SO42-> Cl-> F-. The adsorption isotherms were well fitted to Freundlich model, and increasing temperature was favorable for adsorption. Moreover, the kinetic experimental data of the adsorption fitted to the pseudo-second-order kinetic equation.
  • ZHOU Guang-tao
    China Rural Water and Hydropower. 2018, (6):  102-107. 
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    The study of the ecological runoff for the river is of great significance for maintaining the health and stability of the river. According to the monthly runoff data from 1951 to 2013 in the Baoquanling Station of the Wutong River Basin,the minimum ecological flow and the maximum ecological flow is obtained by using the second minimum ( maximum) value method and the frequency ranking method. Meanwhile,reference to the RVA method,the thresholds for the optimal ecological flow is calculated,the Tennant method is used to evaluate the above results,and the guaranteed rates of the ecological flow are analyzed,the current situation of the water resources development in the river basin and the influence of the future water resources development on the river ecological runoff is analyzed. The results show that the processes for the minimum ecological flow and the maximum ecological flow in the Wutong River Basin obtained by the frequency ranking method are more conducive to maintaining the ecological health and stability. During the non-flood season from January to February and December,the river is prone to extreme flow conditions,but the flow conditions of the river in most months are favorable to the river habitat. the construction of the Guanmenzuizi Reservoir and Guanmenzuizi Irrigation Area will improve the river water resources development and utilization degree in the future. At the same time,the minimum ecological flow at the Baoquanling Station from April to December and the normal ecological water demand of the sensitive period( from April to August) may not be satisfied,and Guanmenzuizi Reservoir and Xilin River Reservoir in the future can be controlled through the integrated scheduling to ensure the habitat of the downstream river as far as possible in a more favorable traffic conditions. The results of the above research serve as a reference for future water resource management.
  • XIAO Xue,LI Chuan-qi,YANG Xing-zi,HAN Dian-cheng
    China Rural Water and Hydropower. 2018, (6):  108-112. 
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    In the water delivery project by gravity with the regulating pool closely branch form connected with the trunk pipe,based on the characteristic method to simulate the long-distance water gravitational transportation process of the opening and closing valve in the pipe system. By jointing regulating-pool and trunk pipe in the beginning and then opening the middle valve of the pipeline,upstream water inlet valve,downstream outlet side of the valve in turn to delivery water,jointing regulating-pool and trunk pipe in the beginning and then close the downstream water inlet valve,close the valve between regulating-pool and trunk pipe in turn to cut off the water delivery process. These operation programs can effectively reduce the water hammer pressure to ensure the safety of water supply
  • ZHAO Xing-ming,WANG Xuan
    China Rural Water and Hydropower. 2018, (6):  113-117. 
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    Optimization search of looped pipe network to achieve the building of automatic tree generation by Kruskal algorithm. All the pipes are traversed on the Auto CAD platform and deledted the screened pipes to form the tree pipe network.Retain the necessary pipes by identifying the weight of each pipe segment. The design effciency of the initial distributed fluxes can be improved by implement the automatic spanning tree.
  • SONG Wei-kun1,2 ,WU Xiao-mei 1,2 ,LI Xiao-qin1,2 ,JIA Yan-nan1,2 ,LIAO Li-sha1
    China Rural Water and Hydropower. 2018, (6):  118-121. 
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    Measuring the quantity of water withdrawal and consumption of rural drinking water supply projects is the necessity of implementing of relevant laws and regulations, the necessity of practicing the strictest water resources management rules, and the necessity of guaranteeing the sustainable running of rural drinking water supply projects. Through the investigation of application of measuring equipment in rural drinking water supply projects in our country, ultrasonic flowmeter and electromagnetic flowmeter are the main measuring equipments of water works. And mechanical water meter, IC card intelligent water meter, and remote water meter are the main household water meters. At last, the reason of different installation rate and low accuracy were analyzed, and several suggestions were also put forward in order to improve water quantity measurement and promote sustainable running of rural drinking water supply projects.
  • CHEN Yu-lin1 ,ZHU Bin1 ,WEI Jun1 ,CUI Ning-bo1,2 ,ZHANG Qing-wen1 , FENG Yu1,4 ,HU Xiao-tao3 ,GONG Dao-zhi 4
    China Rural Water and Hydropower. 2018, (6):  122-127. 
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    The comprehensive evaluation of operation level of irrigation districts is the primary basis for investment decision-making in irrigation districts and also the basis for promoting the modernization of irrigation districts. In or der to improve the comprehensive evaluation accuracy of operation level of irrigation district, this text takes seven ty pical irrigation districts of Sichuan Province as an example to carry on the empirical research. Combined with the act ual situation in Sichuan irrigation district, taking all factors into consideration, it is established according to the princ iples of systematization, scientificity and practicability The comprehensive evaluation index system of operation leve l of irrigation district was established. The game theory was used to comprehensively determine the subjective empo werment determined by the G1 method and the objective empowerment determined by the improved entropy method. The results based on the weighted rank sum ratio method (Weighted RSR Method) show that the operation levels (weighted RSR estimates) of 7 typical irrigation districts in Sichuan Province are in the order of Tuanjie irriagtion district(0.7296), Yidaqu irriagtion district(0.6807), Gaozhong irriagtion district(0.6461), Moertan irriagtion district(0.6233), Dongfengyan irriagtion district(0.5992), Shitan irriagtion district(0.5744) and Xili irriagtion district(0.5418); The resulut of model evaluation are basically consistent with those of the irrigation district, which can provide a new method for the comprehensive evaluation of the operation level of the irrigation district method.
  • ZOU Jian1 ,LI Tao2,3 ,QU Shao-jun2 ,WANG Wei 3
    China Rural Water and Hydropower. 2018, (6):  136-139. 
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    Lateral intakes in open channel are often used for diverting water from river,which has a great impact on the flow regime because of the constraint near the intake mouth. Those factors influence the branch ditch heavily. With the complicated regime in diversion of tributary,the simulation model was established to analyze hydraulic characteristics of bifurcation area based on MIKE21,a model for plane-2D flow. The flow under three slope coefficients 0,1 and 2 respectively are simulated with discharge varying from 1 L/s to 10 L/s. The flow pattern at the entrance of the diversion and the influence of the parameters on the diversion ratio are analyzed and studied. The results show that,under the same slope coefficient,the range of recirculation zone increases,the effective width of branch decreases,the contraction coefficient decreases and the diversion ratio decreases with inlet discharge increasing. Under a fixed discharge,the range of recirculation zone decreases,the effective width of branch increases and the contraction coefficient and the diversion ratio increases with slope coefficients increasing. With Froude number increasing,the diversion ratio decreases gradually with larger the slope coefficient. The relationship among the diversion ratio and the Froude number and the contraction coefficient is obtained,the correlation coefficient is good and has been verified.
  • JIANG Lin-lin1 ,ZHAO Chuan2,3 ,ZHANG Jiong-jiong4
    China Rural Water and Hydropower. 2018, (6):  140-144. 
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    : In order to study the dam slope seepage stability of sand rock asphalt slag dam in Southwest China research system,taking trunk Tsui asphalt concrete core rockfill dam as an example,the mechanical parameters of material performance indicators provide an indoor test of dam based on the limit equilibrium method to calculate the analysis of dam slope trunk Tsui asphalt core wall dams in different operation under the condition of stability,results show that: the dam slope damage to the deep penetrating sliding,the nonlinear strength index of dam slope stability calculation is more reasonable; under all operating conditions,the stability safety factor of Fs on the downstream dam slope are larger than the standard minimum requirement value,meet the standard requirements; the rockfill permeability,without groundwater level drawdown of water level under the condition of hysteresis. The research results can be used for a reference for the design and construction of the asphalt core wall dams in Southwest China.
  • XIANG Yun-long1 ,FU Wen-xi 1 ,ZHOU Hong-fu2
    China Rural Water and Hydropower. 2018, (6):  145-150. 
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    In order to study the influence of surface runoff drag force on the stability of multi - layer slope, a multi - layer seepage - runoff coupling model was established. The Navier-Stokes equations are used to describe the surface runoff. The Brinkman-extended Darcy equation is used to describe the seepage of the soil. The fluid motion in the runoff and seepage regions satisfies the continuity equation, and the fluid at the interface satisfies the continuous and double shear boundary conditions. According to the above conditions, the velocity distribution of the runoff and seepage areas is deduced, and the Newton internal friction law is used to find the drag force of the flow at the interface between the runoff and the seepage. Based on the stress characteristics of each layer, the stability of multi - layer slope under runoff condition is analyzed by rigid body equilibrium equilibrium theory, and the stability coefficient of each layer is obtained. The effects of runoff depth, slope gradient and upper and lower soil thicknesses on the stability coefficient of upper and lower soil layers were discussed with engineering examples. The results show that the stability coefficient of the upper soil layer is 0.92 and the stability coefficient of the lower soil layer is 1.18 when considering the drag effect of the surface runoff. When the drag force effect is not taken into account, the stability coefficient of the upper soil layer is 1.02, The stability factor is 1.23. The safety factor of the upper soil decreased by 9.95%, and the safety factor of the lower soil decreased by 4.99%. Therefore, in the multi-layer slope stability analysis and calculation, should consider the role of surface runoff drag force.
  • DONG Li 1 ,HOU Tian-shun1,2 ,LUO Ya-sheng1 ,Sibel Pamukcu2
    China Rural Water and Hydropower. 2018, (6):  151-156. 
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    To study the dynamic strength characteristics of light weight soil mixed with EPS beads, taking loess as raw material soil ,the dynamic triaxial tests of light weight soil are tested under 5 different EPS contents by weight (0.14%, 0.31%, 0.54%, 0.86%, 1.31%), and 3 different cement contents by weight (10%, 15%, 20%). The results show that the dynamic strain is relatively stable, there is no sudden change of deformation, and the compressive strain is obviously larger than that of tensile strain during the cyclic loading. 5% compressive strain is chosen as the failure criterion. With the increase of confining pressure and cement content, the dynamic strength of mixed light soil increased. With the increase of EPS ratio, the dynamic strength of the mixed light soil decreased. Compared with the dynamic strength of remolded loess, the increased range of dynamic strength of light weight soil under different mixed ratio is 20.8% ~ 232.9%. It indicates that light weight soil can be used in ground improvement for some special subgrade.
  • YU Jin1 ,ZENG Peng1 ,LI De2 ,CAO Ping-zhou1
    China Rural Water and Hydropower. 2018, (6):  157-161. 
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    The engineering background of this research is the project of the YunGuChuan inverted siphon in Qinghai Province. In this paper, using one-way sequential coupling method, the finite element analysis software ANSYS is used to simulate the residual stress and deformation distribution of welded steel pipes with different welding process, establishing the three-dimensional welding finite element model of fully-welded grooved welded pipe considering thermosetting coupling effect. Welding heat source uses endogenous heat rate source model and multi-channel welding process uses heat source unit life and death simulation. Through the comparison and analysis of the level and distribution of internal residual stress and residual deformation after welding, the proposals for the welding technology of the pressure steel pipe are put forward, which provide the technical basis for the production of actual engineering pressure steel pipes. It is also a technical reference for similar projects.
  • HU Song-tao1 ,ZHANG Yu-chi 1,2 ,GAO Jiang-lin1,2
    China Rural Water and Hydropower. 2018, (6):  162-166. 
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    Abstract:This essay is aimat the security problems of TongguDaduan Reservoir during the operation, focuseson the 6th non-overflowstone masonry dam section, builds the three-dimension finite element model of the 6th dam section before and after reinforcement, bases on the similarity of seepage field and temperature field, makes seepage calculation on the dam section under the operation condition and normal pool level condition through the ANSYS thermal analysis module. The results show that the model calculation value of the dam section’s pressure headagrees well with its monitoring point measured value under operation condition, the seepage filed which calculated by numerical simulation can reflect its distribution characteristic of dam and bedrock as a whole. Under normal pool level condition, there is a significant decrease in free surface、pressure head and seepage pressure of the dam section after reinforcement, the seepage gradient of dam and impervious curtain is relatively less. When there is a connection curtain, the pressure head between the main dam foundation connection curtain and the dam surface anti-seepage face slab is obviously less than the pressure head in this section without connection curtain. Above all, The new connection curtain could connect the dam impervious body with the dam foundation impervious body and make a complete-closed impervious system. The comprehensive reinforcement measure improved seepage filed condition effectively and achieved predictive effect on anti-seepage treatment. Meanwhile, the researchresult can provide a reference for this project on the stone masonry dam seepage control.
  • China Rural Water and Hydropower. 2018, (6):  167-168. 
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    In the past few decades we have been pursuing to develop hydraulic technology at the cost of ecological environment, however multiple floods, droughts and geological disasters warned us that short-term benefits at the expense of the nature are not desirable. This paper takes the ancient irrigation project ‘Chatanbei’ as an example and from aspects of historical and cultural value, engineering value, scientific value and economic value, respectively, analyzes its water control concept, which advocates the tao way to follow nature and harmony between human and water, and suggests problems in modern hydraulic constructions, so as to explore the precious experiences in the inheritance and innovation, utilization and protection, management and development of ancient water conservancy projects, and provide reference for the construction of modern ecological water conservancy projects.
  • SU Hui,ZHANG Zhong-wu,WANG Juan
    China Rural Water and Hydropower. 2018, (6):  169-173. 
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    Taking Shanxi Province as the research area, this paper chooses three economic development elements of GDP, population and land area, respectively, with the total amount of water resources and water resources Quantity and two indicators to establish the coordination model to analyze the spatial coordination features of water resources and economic development. The results show that (1) when the total amount of water resources is the evaluation index, the coordination status is better in the areas with abundant water resources; (2) When using the water resources as the evaluation index, the coordination status is better in economically developed areas; Aspects, the Gini coefficients of two water resources indicators and various economic development elements are respectively calculated, and their time coordination characteristics are analyzed. The results show that overall coordination between the total amount of water resources and the amount of water resources used and the various economic development elements fluctuated little between 2008 and 2015. The total amount of water resources is highly coordinated with the land, while the amount of water used is highly coordinated with the population and GDP.
  • XU Jian-lin1 ,HE Zhong-wei 2
    China Rural Water and Hydropower. 2018, (6):  174-177. 
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    According to the unique hydraulic characteristics of the transition process of pumped storage power station,application of governor water level monitoring performance,real -time collection of head is achieved. Taking the Ninghai Pumped Storage Power Station for an example,this paper studies the influence of closing laws of guide vane on transient process under the maximum head,the rated head,and the minimum head. The results show that when the head of the unit is larger than the rated head below the maximum head,it is advisable to adopt the delay line closing law. When the head is lower than the rated head,it is necessary to adopt the 20s single-slope closing law. It can effectively improve the spiral case pressure and the draft tube presure,reduce the unit load rejection when the load shedding operation
  • TAN Jian-bo1,2 ,MA Xiao-yi2 ,HE Zi-li2
    China Rural Water and Hydropower. 2018, (6):  178-181. 
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    In order to obtain the turbine adjustment characteristics data in the small flow and small opening area, based on genetic algorithm to optimize the connection parameters of BP neural simulation network and proportional interval characteristic-points fitting algorithm to extend the curve surface, the turbine torque and flow characteristics relative value data has been trained and extended to all operation area. The experimental results show that the turbine integrated characteristic curve has been numerically and intelligently extended processing by hydro-turbine’s complex adjustment characteristics with multi-value and non-linear was coveted to space characteristic surface and through the automatically training with the neural network system. The accurate data in all operation area generated by the nonlinear neural network model of hydraulic turbine built in this paper can provides a detail data support basis to ensure the control decisions for regulation guarantee calculation of hydro-turbine.
  • China Rural Water and Hydropower. 2018, (6):  182-184. 
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    The basic conditions of the Shenzhen Reservoir(Phase Two)Power Station were introduced, the necessity of the transformation was analyzed, and the principles and plans for technological transformation were put forward. The effect of the technical transformation of the power station was analyzed in light of the actual operation conditions.