Numerical Simulation of Mean Flows and Turbulent Structures of Partly-Vegetated Open-Channel Flows using the Nonlinear k-ε Model

Title & Authors
Numerical Simulation of Mean Flows and Turbulent Structures of Partly-Vegetated Open-Channel Flows using the Nonlinear k-ε Model
Choi, Seongwook; Choi, Sung-Uk; Kim, Taejoon;

Abstract
This study presents a numerical modeling of mean flow and turbulence structures of partly-vegetated open-channel flows. For this, Reynolds-averaged Navier-Stokes equations with vegetation drag terms are solved numerically using the non-linear k-$\small{{\varepsilon}}$ model. The numerical model is applied to laboratory experiments of Nezu and Onitsuka (2001), and simulated results are compared with data from measurement and computations by Kang and Choi`s (2006) Reynolds stress model. The simulation results indicate that the proposed numerical model simulates the mean flow well. Twin vortices are found to be generated at the interface between vegetated and non-vegetated zones, where turbulence intensity and Reynolds stress show their maximums. The model simulates the pattern of the Reynolds stress well but under-predicts the intensity of Reynolds stress slightly.
Keywords
Partly-vegetated open-channel flow;Turbulence model;Mean flow;Turbulence structure;Non-linear k-$\small{{\varepsilon}}$ model;
Language
Korean
Cited by
1.
2차원 수치모형을 이용한 원형군락 하류의 흐름특성 수치모의,김형석;박문형;

한국수자원학회논문집, 2015. vol.48. 11, pp.891-903
2.
LES를 이용한 침수식생을 통과하는 난류흐름 수치모의,김형석;

한국산학기술학회논문지, 2015. vol.16. 9, pp.6305-6314
1.
Numerical Simulation of Flow Characteristics behind a Circular Patch of Vegetation using a Two-Dimensional Numerical Model, Journal of Korea Water Resources Association, 2015, 48, 11, 891
2.
Numerical simulations of turbulent flow through submerged vegetation using LES, Journal of the Korea Academia-Industrial cooperation Society, 2015, 16, 9, 6305
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