中文摘要：

结合临界流原理,提出适用于灌区田间进水口水量计量的新型量水设备——田间便携式短喉槽,以满足量水槽结构简单、水头损失小、量水精度较高、流量计算公式简明的要求。田间便携式短喉槽是一种喉道宽度为76 mm、槽底为平底的短喉道量水槽。在自由出流、淹没出流两种工况下对不同流量下的水力特性进行试验研究,结果表明：该量水槽过流顺畅,量测流量最大可达40 L/s,能够满足灌区末级渠道的量水要求;断面流速分布为中间流速大、两侧流速较小,且自由出流工况下的流速略大于淹没出流工况下的流速;水头损失较长喉槽的小;根据对弗劳德数的分析得到临界水深断面位于喉道后半段;通过回归分析得到田间便携式短喉槽的上游水深—流量计算公式,其最大测流误差为9.16%,满足灌区田间量水精度要求。

英文摘要：

Portable short-throat flume in the field is an emerging technique developed for flow measurement of inlet in the field based on the principle of critical flow, which can satisfy the requirements of simple structure, less head loss, high accuracy of flow- measurement and sim-ple equations of depth versus discharges. Experiments were conducted under the free and submerged flow conditions for different discharges in the 76 mm width flume with a flat bottom. The results obtained from experiments show that water flows smoothly through the flume with dis-charges up to 40 L/s. The velocity of central cross-section is larger and the velocity near both side walls is smaller. Further, the velocity un-der the free flow condition is larger than that under the submerged flow condition. Comparing to the long-throat flume, the head loss of porta-ble short-throat flume in the field is significantly less. The section of critical depth is located at the throat section by analysis of Froude num-bers. Regression models developed for upstream depth versus discharge are satisfying with the relative error of 9.16%, which meets the com-mon requirements of flow measurement in irrigation areas.