Journal of New Approaches in Water Engineering and Environment
Scientific Journal

Chiu's entropy theory application for simulation of flow field velocity in river bends (Case study: Gorganrood River bend)

Document Type : Original Article

Authors

Amieahmad Dehghani 1
Iman Yousefabadi 2

1 Water Engineering Dept., Gorgan University of Agricultural Sciences and Natural Resources

2 Master of Science in Civil Engineering, Consultant Engineers

https://doi.org/10.22034/nawee.2022.153891
Abstract
In rivers and especially in river bends, the variation of stream-wise flow velocity in width and depth directions is non-uniform and is affected by many factors including secondary flows, bed and bank roughness, and flow hydraulic characteristics. For calculation of two-dimensional flow velocity distributions in straight rivers many approaches have been presented by researchers, while in meandering rivers, due to the complex mechanism of flow pattern, the solution of velocity field is carried out by computational fluid dynamics software packages. In this research, the Chiu's probabilistic theory was used for solution of the flow velocity field in a river bend on the Gorganrood located in Goletsan province. Considering the lack of measured point velocity data in river bends, 6 field measurement series were collected in one of bends located about 200 m upstream of Aghghala hydrometric station. Among these measurements, 4 series are selected for the model calibration and 2 remaining series for the model validation. The results showed that the Chiu's method has an acceptable accuracy in simulation of flow velocity fields for river bend. The statistical measures for the obtained point velocities indicated that the mean errors of this method are 4.9 and 3.5% in the calibration and validation phases, respectively. The mean errors for the calculation of total flow discharges are 5.9 and 6.0% respectively.

Keywords

Chiu'
s method
Flow velocity field
Meandering Rivers
River bend
2D simulation
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Journal of New Approaches in Water Engineering and Environment
Volume 1, Issue 1
March 2022
Pages 15-26

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