中文摘要：

灌区量水是灌区用水管理的关键技术之一。目前灌区量水设备种类繁多，但能用于田间的量水设备较缺乏。标准巴歇尔量水槽量水精度高，但形状复杂且造价较高，本文在其基础上设计制作了一种形状简单、成本低、便于携带和田间安装的田间简易平底短喉道量水槽，量水槽喉口宽度51mm、长度774mm，单槽适用流量范围大致为6～20L／s，双槽适用流量范围可达36L／s。试验通过对16种流量下量水槽内11个控制断面的水位进行观测与分析，拟合得到自由出流条件下上游水深与流量公式，与实测流量比较，平均相对误差为一0．11％，最大相对误差为7．06％；从水力学角度分析了不同流量下佛汝德数、断面比能沿槽身各控制断面的变化规律，确定该量水槽临界水深断面位于喉口段的中部偏后段，从而确定该量水槽的喉口段长度适宜。

英文摘要：

Flow measurement is a key technique of agricultural water management in irrigation areas. At present, various types of flow-measuring devices are available for open channels, but few of them are suitable for field use. Parshall flume has a high accuracy but with a complex structure and high cost. This paper presents a modified Parshall flume that has a flat base, simple structure, and lower cost. This new flume is 774 mm long with a throat of 51 mm wide, and it is easy to carry around and install in the field. Its application range of discharge is 6-20 L/s of a single flume and up to 36 L/s of double flumes. We have taken water level measurements at 11 cross sections under 16 different discharges and obtained by data fitting an empirical formula of discharge versus inflow water depth for the conditions of free outflow. Relative to the measurements, the error of this formula is -0.11% on an average and 7.06% in maximum. Analysis on the variations in Froude number and specific energy at different control sections along the flume under different discharges shows that the critical depth occurs at a cross section near the rear end of the throat, which indicates that the throat length is appropriate.