【作者】 杨莉；

【导师】 王新宏； 巨江；

【作者基本信息】 西安理工大学 ， 水利工程（专业学位）， 2019， 硕士

【摘要】 东雷抽黄塬下总干渠工程运行多年,渠道泥沙淤积问题十分突出,最严重时渠道输水能力不足设计的40%,严重影响灌区灌溉效益的发挥。本文采用数值模拟的方法对东雷抽黄塬下总干渠运用方式进行研究,对控制渠道淤积具有重要意义。本文首先整理分析了东雷抽黄灌区塬下总干渠投入运用以来渠首来水来沙和渠道泥沙冲淤变化过程,以及塬下总干渠实际调配水运用方式等实测资料,总结了塬下总干渠泥沙冲淤变化的基本规律。其次,在现有一维非均匀悬移质泥沙输移数学模型的基础上,通过修改完善,使之适用于东雷抽黄灌区塬下总干渠的水沙条件和渠道边界特性,并利用塬下总干渠实测淤积资料,对模型进行了验证计算,结果表明累计冲淤量的计算值比较接近实测值。最后,利用验证完善后的数学模型,针对渠首典型年来水来沙情况,对不同运用方式情况下,塬下总干渠沿程冲淤变化过程进行了模拟计算。通过分析对比不同方案塬下总干渠泥沙淤积量等计算结果,认为按照现状运用模式渠道泥沙淤积形势无法改善,利用退水渠通过加大塬下总干渠流量冲刷是控制渠道泥沙淤积的可行方案。通过多方案优化对比表明:(1)加大塬下总干渠流量冲刷的最优时期是春灌含沙量较低时段,即每年4月7日至4月29日共23天;(2)塬下总干渠冲刷时的最优流量为45m3/s。按照该方案运用,塬下总干渠减淤率最大为59.63%,每方减淤耗水费用仅为人工清淤费用的1/5,该方案在技术及经济方面均可行。更多还原

【Abstract】 The main canal of Donglei irrigation district has been running for many years,and the problem of sediment in the canal is very prominent.The most serious is that the water delivery capacity of the canal is less than 40%of the design,which seriously affects the irrigation efficiency of the irrigation district.This paper used the mathematical model to study the operation mode of the main canal,which is very significant to control the canal deposition.First,this paper summarized the basic law of changes of sediment in the main canal by the systematical analysis of the data,includes the inflow of water,sediment from the head and the process of erosion and siltation of the canal,the actual allocation of water in the system and so on,which is measured since Donglei irrigation district was put into operation.Secondly,On the basis of the existing 1-D non-uniform suspended sediment transport mathematical model,the paper improved and modificated it to be suitable for the water sediment conditions and canal boundary characteristics of the main canal in the Donglei irrigation district,and used the measured siltation data ofthemaincanal to verify it,theresultshowsthat the calculated value of the accumulated siltation is basically consistent with the measured value.Finally,according to the situation of water and sediment coming from the head of the canal in typical year withthe under different operation modes,the verified mode is used to simulate the process of erosion and deposition of the main canal.Based on the analysis and comparison of the calculation results of different schemes,it is considered that the canal sediment deposition situation cannot be improved according to the current application mode,and the feasible scheme to control the canal sediment deposition is to use the drainage canal to increase the flow of the main canal.The results show that:(1)the optimal period to increase the flow of the main canal is in spring irrigation,when the main canal is in low sediment concentration,that is 23 days from April 7 to April 29 every year;(2)the optimal flow of the main canal is 45m3/s.According to the scheme,the maximum silt reduction of the main canal is 59.63%,the water consumptioncost is only 1/5 of the artificial dredging cost,which is feasible in both technical and economic aspects.更多还原