IAHR Document Library

« Back to Library Homepage « Proceedings of the 37th IAHR World Congress (Kuala Lumpur, 2...

Numerical Modeling of Turbulent Secondary Flow in a High-Amplitude Meandering Channel

Author(s): Joongcheol Paik, Sang Deog Park

Linked Author(s): Joongcheol Paik

Keywords: Meandering channel, turbulent flow, numerical modeling, secondary flow, helical motion

Abstract: The flow structure in the meandering channel is characterized by the helical motion and the shear layer emanating from the inner wall and forming flow separation regions near the bend apex. The production of turbulent kinetic energy is correlated to the recirculation cells of which the generation is related to the local curvature. Mean free surface flow and turbulence characteristics of the secondary flow in a periodic, asymmetric, high-amplitude meandering channel retaining high-order harmonic modes are numerically reproduced by a three-dimensional unsteady numerical solver. The turbulent flow is resolved by the delayed detached-eddy simulation (DDES) to elucidate the dynamic behavior of the turbulent secondary recirculation and flow separation. The variation of instantaneous free surface is captured by aid of a two-phase volume of fluid method. The numerical simulation reproduces the distinct mean flow features including the secondary recirculation cells, flow separation forming shear layers from side walls and free surface gradient in both streamwise and transverse directions that observed in the experiment. Based on the good agreement between computed time-averaged flow fields with the measurement, the present numerical solutions elucidate the rich dynamics of complex, three-dimensional turbulent recirculation cells and shear layers between cells


Year: 2017

Copyright © 2024 International Association for Hydro-Environment Engineering and Research. All rights reserved. | Terms and Conditions