短喉堰自由出流流量系数试验研究

摘要

The usage of short throat flume in measuring the flow is increasing in irrigation areas,but there is no proper and widely used calculation formula of flow coefficient under the conditions of free outflow. The experiment set up 3 kinds of experimental models of the ratio between the throat diameter and weir width,drew the relative experimental data under the conditions of free outflow,gave the monadic regressive analysis on free out-flow coefficient,got the relative empirical formula,and also carried out the error analysis on the results. The absolute value for the maximum rela-tive error was less than 2%,which met the accuracy requirements,and the empirical formula was reasonable.%灌区利用短喉堰测量流量日益增多，但尚没有应用范围较广的规范的自由出流流量系数计算公式。建立了三种喉颈与渠宽比的短喉堰试验模型，在自由出流情况下得到相关试验数据，并对自由出流流量系数进行一元回归分析，得到相关经验公式，对其计算结果进行误差分析，最大相对误差的绝对值均小于2％，满足精度要求，经验公式合理。