非满管流对渠管结合输水系统水力特性的影响  

Impact of partially filled pipes on hydraulic performance of canal-pipe water delivery systems

作　　者：李蕊 吕谋超[2,3] 贾晓萌 王鸿飞 LI Rui;LYU Mouchao;JIA Xiaomeng;WANG Hongfei(Shanxi Water Industry Investment Protection Technology Co.,Ltd,Taiyuan030000,China;Farmland Irrigation Research Institute,Chinese Academy of Agricultural Sciences,Xinxiang 453002,China;Key Laboratory of Water-saving Engineering,Ministry of Agriculture and Rural Affairs,Xinxiang 453002,China)

机构地区：[1]山西水投防护技术有限公司,太原030000 [2]中国农业科学院农田灌溉研究所,河南新乡453002 [3]农业农村部节水灌溉工程重点实验室,河南新乡453002

出　　处：《灌溉排水学报》2024年第11期54-62,共9页Journal of Irrigation and Drainage

基　　金：山西省水利科学技术研究与推广项目(2023GM06);中央级科研院所基本科研业务费专项(IFI2024-10)。

摘　　要：【目的】了解非满管状态下的渠管结合输水系统水力特性。【方法】采用物理模型试验与理论分析相结合的方法,对不同充满度下主渠流速分布与水面线变化、管道流速、分流比的变化规律进行了研究。【结果】不同充满度下主渠各断面紊动强度沿程均呈先升高后降低的变化趋势,在距管道入口纵向2倍、横向1.5倍管径的主渠区域内流速变化较为剧烈;在有管道存在的主渠壁面附近水面线变化剧烈,沿程呈先降低后增大再降低的变化趋势。通过量纲分析得到非满管流速表达式,采用线性回归分析法拟合得到非满管流速系数计算式,计算值与实测值之间的相对误差不超过8.81%。当主渠流量不变时,非满管流速系数随主渠傅汝德数的增大而增大,随水深比、充满度的增大而减小,分流比随充满度的增大而增大;当充满度不变时,随着主渠流量的增大,非满管流速系数增大,分流比减小。【结论】非满管流对主渠的影响范围有限,在安装闸阀以及量水设备时要尽量避开相关影响区域,采用本研究推导的流速系数公式只需获得主渠的傅汝德数与水深值,即能快速计算非满管流速值,在来水流不变的情况下可通过增大主渠水深来获得较大的管道流量。【Objective】Changes in water pressure in pipe networks can cause partial filling of pipes,leading to non-full flow.The objective of this paper is to investigate the impact of non-full flow on the hydraulic performance of canal-pipe water delivery systems.【Method】The study was based on experimental and theoretical analysis.We examined the distribution of water velocity in channels,changes in the water surface profile,flow rates in pipes,and the diversion ratio under different pipe-filling levels.【Result】The water velocity distribution along the main channel remained consistent at different filling levels in the pipes,with notable changes occurring within regions approximately twice the longitudinal and 1.5 times the transverse diameter of the pipe.Water velocity fluctuations were most pronounced near the channel walls at the water surface,following a pattern of initial decrease,subsequent increase,and final decrease along the flow path.Through dimensional analysis,a formula was derived for calculating the water velocity coefficient,with a maximum relative error of 8.81%compared to experimental data.For a constant water flow rate in the main channel,the velocity coefficient for the partially filled pipes increased with the Froude number of the main channel but decreased as the water depth ratio and the filling level increased.Additionally,the diversion ratio was found to increase with filling levels.At a constant filling level,increasing the flow rate in the main channel increased the velocity coefficient in the pipes and reduced the diversion ratio.【Conclusion】The impact of partially filled pipes on water flow in the main channel is minor.Installing gate valves and water measuring equipment should avoid areas that are likely to be impacted.The formula we derived for calculating velocity coefficient only needs the Froude number and water depth in the main channel,and it can quickly calculate water velocity in partially filled pipes.Under certain conditions,increasing water depth in the main channel c

关 键 词：非满管流 渠管结合 流速 水面线 分流比 

分 类 号：S274.4[农业科学—农业水土工程]