| This article has been：Browse 2174Times Download 3245Times |
scan it! |
|
|
| DOI：10.13522/j.cnki.ggps.2017.0732 |
|
| Measuring the Hydraulic Characteristics of the Triangle Long-throated Flume Used in Furrow Irrigation |
|
XUE Cheng, WANG Wene, HU Xiaotao, LIU Haiqiang
|
|
Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A & F University, Yangling 712100, China
|
| Abstract: |
| 【Objective】 Furrow irrigation is the most common irrigation method and in this paper, we proposed a device to measure its flow rate. The device is easy to install and especially suitable for field furrow irrigation in northern China.【Method】 Hydraulic performance test of the device under free flow and submerged outflow was carried out at eight flow rates ranging from 1.03 to 15.05 L/s. We measured and analyzed the water level at 14 control sections along the flume, from which the formulae for calculating water-depth discharge rate under the free and submerged flows were derived.【Result】The formulae for the discharge rate under different outflow conditions were fitted to the experimental results. Its maximum relative error under free flow and submerged flow condition was -3.61% and 6.54% respectively, and the average relative error was approximately 0.5%. The specific location of the critical water depth section was at the front middle part of the throat, between 325 and 385 mm to the inlet of the flume. The critical submergence of the triangular long throat flume reached 0.83.【Conclusion】The flow rate that the single portable triangular long throat flume can measure is in the range of 1 to 15 L/s, the suggested throat length is 210 mm, and the critical submergence is between 0.80~0.83. |
| Key words: furrow irrigation; portable triangle long-throated flume; Fr; hydraulic performance; formula of water depth versus discharge |
|
|
