Derivation of flow relationship of triangular throat flume using incomplete self-similarity theory

Subject Areas : watere sciences

Hossein Soltani Kazemi ¹ , Mohsen Solimani Babarsad ² , Mohammad hossein purmohammadi ³ , Hossein Eslami ⁴ , hossein ghorbanizadeh kharazi ⁵

1 -
2 - عضو هیات علمی گروه آبیاری دانشگاه آزاد اسلامی واحد شوشتر
3 - گروه آب دانشگاه شوشتر
4 - 4Department of Water Science, Water Science and Environmental Research Center, Shoushtar Branch, Islamic Azad University, Shoushtar, Iran.
5 - 5Department of Water Science, Water Science and Environmental Research Center, Shoushtar Branch, Islamic Azad University, Shoushtar, Iran.

Received: 2024-07-03 Accepted : 2024-08-15 Published : 2024-09-18

Keywords: flow measurement, free flow, experimental modeling, incomplete self-similarity,

Abstract :

Flumes, like weirs and orifices, are one of the flow measurement structures in open channels based on the control section. This research uses experimental modeling to determine the flow rate relationship for a flume with a triangular throat. The experiments of this research were carried out in a laboratory channel with a length of 20 m, a width of 0.6 m, and a depth of 0.5 m in the hydraulic laboratory of Khuzestan Water and Electricity Organization. A total of 101 tests were performed for four flume models with triangular throats with heights of 20, 25, 30, and 35 cm in a range of flow rates between 3.39 and 55.378 L/s. A general relation was first extracted using dimensional analysis for the triangular throat flume’s discharge. Then, using the principle of incomplete self-similarity, the extracted relation became simpler. By using pre-processing, it was found that Q⁄√(gB^5 ) ratio has better compatibility with the studied flume. Finally, non-linear multivariate regression transformed the general relationship into a mathematical form. This relationship's R2, RMSE, and MAPE values are 0.98, 0.0026, and 0.0021, respectively.

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