Ultrasonic Transit-time Discharge Determination in Rectangular Open Channel |
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| H. Hu, Z. Cheng, P. Gruber, Z. Wang |
- Abstract:
- Ultrasonic Transit-time method is a good choice to measure the open channel discharge. To investigate its performance in the rectangular open channels, a 26 m long, 2 m wide, 1.2 m deep open channel facility was built with an over-fall head tank providing a very stable flowrate of 1.5 m³/s in maximum and 39 typical cases were tested. The tested results verified that ultrasonic transit-time method can be well used to measure the discharge in rectangular open channels. However, due to unavoidably disturbing the flow patterns and introducing some errors, thus the transducers should be made as small as possible to improve the measuring accuracy. In addition, more paths should be used to produce smaller errors. And at least two paths are suggested to be mounted in the range of hi/H > 0.7 to better reflect the influence of the free surface. Comparing sub-discharges in all zones, it can be found that substantial differences between mean-section method and Giordano Law exist below the lowest path. Larger Kb, for example 0.9, makes mean section method produce closer measurements to Giordano Law.
- Keywords:
- Open channel; Discharge determination; Ultrasonic transit-time method; Transducers’ arrangement
- Download:
- IMEKO-TC9-2019-087.pdf
- DOI:
- 10.21014/tc9-2022.087
- Event details
- IMEKO TC:
- TC9
- Event name:
- FLOMEKO 2022
- Title:
19th International Flow Measurement Conference 2022
- Place:
- Chongqing, CHINA
- Time:
- 01 November 2022 - 04 November 2022