Accurate measurement of irrigation water consumption in small channels is an important link in achieving reasonable irrigation area management and agricultural water pricing and improving agricultural irrigation water use efficiency. Fixed water measuring flumes have a high construction cost and are prone to causing local channel sedimentation, compromising the safety of channel water transmission and flow measurement accuracy. Portable water measuring flumes can be used repeatedly in channels within a certain contraction ratio, and the duration of one water measurement is short (generally less than 5 min), which will not cause sedimentation. A new portable primary and subsidiary fish-shaped flume has been proposed by dividing 1 fish-shaped cylinder into 3. The flow measurement and hydraulic performance of measuring flumes with different contraction ratios in a U-shaped channel under different working conditions were studied using prototype experiments and numerical simulation. Compared to the existing portable flume, the primary and subsidiary fish-shaped flumes have achieved high flow measurement accuracy, a large critical submergence degree, a low backwater height, and low head loss. The head loss can be reduced by selecting a suitable length-width ratio and column spacing distance.

中文翻译：

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U型渠道便携式主副鱼形水槽水力特性及流量测量性能

准确计量小渠道灌溉用水量，是实现合理灌区管理和农业水价、提高农业灌溉用水效率的重要环节。固定式测水水槽建设成本较高，且易造成渠道局部淤积，影响渠道输水安全和流量测量精度。便携式测水水槽可在一定收缩率的渠道内反复使用，且一次测水持续时间短（一般小于5分钟），不会造成沉淀。将1个鱼形圆柱体分成3个，提出了一种新型便携式主副鱼形水槽，并利用样机研究了不同工况下U形通道内不同收缩比测量水槽的流量测量和水力性能。实验和数值模拟。与现有便携式水槽相比，主副鱼形水槽流量测量精度高、临界淹没度大、回水高度低、水头损失小。通过选择合适的长宽比和柱距可以减少水头损失。