Discharge formula for rectangular sharp-crested weirs

Date

2011-04-01

Author

Aydın, İsmail
Altan Sakarya, Ayşe Burcu

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Sharp-crested rectangular weirs used for discharge measurement in channels and laboratories are experimentally investigated. Height and width of weir plate are the two parameters characterizing the head-discharge relationship. Laboratory experiments are conducted by measuring the discharge and the head over the weir for variable weir heights and widths. Applicability of various formulations for the discharge coefficient are investigated. Experiments indicate that discharge is independent of weir height, when the weir is operated within an appropriate discharge range. Average velocity over the weir plotted against the weir head displays universal characteristics such that it can be used in the expression of discharge over the weir, eliminating the need for a discharge coefficient. The head-discharge relationship for a rectangular weir has distinct features for the partially contracted weirs and for the fully contracted slit weirs.

Subject Keywords

Open channel flow, Open channel flow, Discharge measurement, Rectangular weir, Sharp crested weirs, Flow measurement

URI

https://hdl.handle.net/11511/41871

Journal

FLOW MEASUREMENT AND INSTRUMENTATION

DOI

https://doi.org/10.1016/j.flowmeasinst.2011.01.003

Collections

Department of Civil Engineering, Article

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Citation Formats

İ. Aydın and A. B. Altan Sakarya, “Discharge formula for rectangular sharp-crested weirs,” FLOW MEASUREMENT AND INSTRUMENTATION, pp. 144–151, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41871.