区域水利灌溉渠道中水利挟沙力模型研究

Study on Sediment Carrying Capacity Model of Water Conservancy in Regional Irrigation Channels

目前,通过计算水流流速、水流剪切力、泥沙沉速、泥沙容重4个参数建立的水利挟沙力模型,得到的水利挟沙力值与实际值拟合度低,因此提出区域水利灌溉渠道中水利挟沙力模型研究。计算水流流速、水流剪切力、水流功率等水流强度参数,并采用无因次化消除参数计算范围,将其转换为无纲量形式;依据泥沙处于河流中受到的影响因素,计算灌溉渠道糙率系数、灌溉渠道剪切力、泥沙沉速等综合特性参数;基于泥沙综合特性和水流强度参数,确定水利与沙力之间存在的关系,得到水利挟沙力表征计算公式,采用数据拟合的方式,确定公式系数和指数值,完成区域水利灌溉渠道中水利挟沙力模型建立。设计模拟数据,模拟水利灌溉渠道,计算水流挟沙实际值。模型与实测值拟合度对比结果表明,研究模型拟合点与1∶1直线完全贴合,与实际值具有较高的拟合度。

At present,the water conservancy sediment carrying capacity model is established by calculating the four parameters of flow velocity,flow shear force,sediment settling velocity and sediment bulk density.The obtained water conservancy sediment carrying capacity value has low fit with the actual value.The research on water conservancy sediment carrying capacity model in regional water conservancy irrigation channels is put forward.The flow intensity parameters such as flow velocity,flow shear force and flow power are calculated,and the dimensionless parameter calculation range is eliminated and transformed into dimensionless form;according to the influencing factors of sediment in the river,the comprehensive characteristic parameters such as roughness coefficient of irrigation channel,shear force of irrigation channel and sediment settling velocity are calculated;based on the comprehensive characteristics of sediment and flow intensity parameters,the relationship between water conservancy and sediment carrying capacity is determined,and the characterization and calculation formula of water conservancy sediment carrying capacity is obtained.The formula coefficient and index value are determined by data fitting,so as to complete the establishment of water conservancy sediment carrying capacity model in regional water conservancy irrigation channels.Design simulation data,simulate water conservancy irrigation channels,calculate the actual value of water flow sediment carrying capacity,and compare the fitting degree between the model and the measured value.The results show that the fitting points of the research model are completely consistent with the 1:1 straight line,and have a high fitting degree with the actual value.