Numerical Modeling of Flow Characteristics for A Reach Reach from Damietta Branch Using K-ε Turbulence Model.(Dept. C)

A A Zidan,K S El-Alfy,M I El-Gamal,M G Abdalla

doi:10.21608/bfemu.2022.222298

Abstract

In this research, a meandering reach from Damietta branch was selected and numerically studied. The aim of this study is to find the vulnerable zones subjected to maximum velocities so as to assign the appropriate methodology of training structures for improving and stabilizing flow conditions. This reach is approximately 6.78 km long, which located between km 95.22 and km 102 downstream of El- Roda gauge station. Field data were collected and analyzed for the modeling process. A 3-D model called IRIC (International River Interface Corporative) based on an explicit finite difference method (Abbott-Ionescu scheme) was applied. Therefore, in order to fulfill such objective, K-ɛ turbulence model was employed using upwind scheme of the advection terms.

Highlights

Flow in curved river reaches is usually under the influence of centrifugal acceleration, which induces transverse velocity component and super elevation in water surface
For the downstream curve, the vulnerable zone is found between km 99.80 to km 101.20 downstream of El- Roda gauge station;
The upstream and downstream curves are subjected to maximum velocity of 1.6 m/sec at km: 96.50 and 1.5 m/sec at km: 101.00;

Summary

INTRODUCTION

Flow in curved river reaches is usually under the influence of centrifugal acceleration, which induces transverse velocity component (helical flow currents) and super elevation in water surface These curved reaches are sometimes stable, there are general tendency of bank failure and bed scour at the outer bend followed by sedimentation at the inner bend. River meandering, lateral migration, deterioration of local navigation depths and flood conveyance are the result of the movement and deposition of bed sediment. Three bend types were defined as: free, limited, and forced; which were classified according to the physical and morphological characteristics and degree of freedom to attain the lateral shifting They concluded that Damietta branch is changing in its planform several times down its course. The aim of this research is to determine accurately the zones subjected to maximum water velocities and scouring processes in a selected reach so as to find the suitable structure used for improving flow conditions at the curves of this reach

FIELD WORK

MODEL SET UP

Ph P C2

MODELING PROCESS

CONCLUSIONS