梯形喉口无喉道量水槽水力性能分析  

Analyzing hydraulic performance of trapezoidal cutthroat flumes

作　　者：冉聃颉 王文娥[1] 胡笑涛[1] 史利洁 RAN Danjie;WANG Wene;HU Xiaotao;SHI Lijie(Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A ＆ F University, Yangling 712100, China;School of Life Sciences, Faculty of Science, University of Technology Sydney, NSW 2007, Australia)

机构地区：[1]西北农林科技大学旱区农业水土工程教育部重点实验室,陕西杨凌712100 [2]School of Life Sciences,Faculty of Science,University of Technology Sydney

出　　处：《水科学进展》2018年第2期236-244,共9页Advances in Water Science

基　　金：国家重点研发计划资助项目(2016YFC0400203);公益性行业(农业)科研专项经费资助项目(201503125)~~

摘　　要：以解决灌区普遍存在的通过增大水头损失来提高测流精度的问题为目标,探究梯形喉口无喉道量水槽在末级梯形渠道中量水的适用性。基于Flow-3D软件,采用RNG k-ε紊流模型和Tru-VOF方法对梯形喉口无喉道量水槽和矩形喉口无喉道量水槽水力性能进行了数值模拟,并通过物理原型试验验证了模拟结果的合理性。研究结果表明:梯形喉口无喉道量水槽测流过程中弗劳德数沿程呈单峰分布,在喉口下游附近出现临界流且喉口上游弗劳德数均小于0.5,满足灌区量水要求;测流过程中,最大流速位置随着量水槽边界变化而变化;对喉口收缩比相同的矩形喉口和梯形喉口无喉道量水槽测流精度、水头损失比较得出,梯形喉口有效改善了小流量时测流误差和大流量时的水头损失。Increasing water head lose to improve the accuracy of flow measurement is a ubiquitous problem in irrigation districts. This research aims to solve the problem. In this context,this research probed into the applicability of the new-type trapezoidal cutthroat flumes in measuring discharge of last trapezoidal channels. Based on Flow-3 D,RNG k-εturbulent model and Tru-VOF technique,numerical simulation was carried out to analyze hydraulic performance of trapezoidal cutthroat flume and rectangular cutthroat flume. Meanwhile,rationality of simulation results was verified by physical prototype test. Results indicated that the distribution of Froude number of trapezoidal cutthroat flume was unimodal; the critical flow appeared near the throat section and the Froude number was less than 0. 5 around the upper throat,which could meet the water measurement requirement in irrigation districts; the position of maximum flow rate varied with the change of the flume＇s boundary. Compared with the rectangular cutthroat flume,both the head loss of trapezoidal cutthroat flume when the flow was large and the measurement accuracy when the flow was small was significantly improved.

关 键 词：梯形喉口 无喉道量水槽 流速分布 测流精度 能量损失 Flow-3D 

分 类 号：S274.4[农业科学—农业水土工程]