Numerical Study on the Effects of the Floodplains Angles on Interaction between the Main Channel and Floodplains in Skewed Compound Channels

مهندسی عمران فردوسی

Article 9, Volume 32, Issue 1 - Serial Number 25, April 2019, Pages 151-164   

Document Type: Research Note

DOI: 10.22067/civil.v32i1.67923

Authors

Bahram Rezaei^* ; Mohamad Mehdi Seif

Bu-Ali Sina University

Abstract

In this research an attempt has been made to model flow field in compound channel with skewed floodplains for two skew angles of 5.1o and 9.2o and relative depths of 0.15, 0.24, 0.41 and 0.50. For numerical modelling the k-e turbulence model and the ANSYS-CFX software were used. The results of numerical modelling of the velocity and boundary shear stress distributions at two selected sections were then compared to the Flood Channel Facility Experimental Data. The study shows that more or less there are good between the experimental data and the results of numerical modelling. Using the momentum equations for the control volumes on the floodplains, the interaction between flow in the main channel and on the floodplains for different skew angles and relative depths has been investigated. The study indicates that in general by increasing the skew angle and water depth due to mass exchange between the subsections, the apparent shear forces at the vertical interface between the main channel and floodplains increases.

Keywords

Numerical modeling; Skewed compound channels; k-e turbulence model; Apparent shear force

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