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http://dx.doi.org/10.3741/JKWRA.2015.48.11.891

Numerical Simulation of Flow Characteristics behind a Circular Patch of Vegetation using a Two-Dimensional Numerical Model  

Kim, Hyung Suk (Hydro Science and Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology)
Park, Moonhyeong (Hydro Science and Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology)
Publication Information
Journal of Korea Water Resources Association / v.48, no.11, 2015 , pp. 891-903 More about this Journal
Abstract
This paper presents numerical simulations of flow around a circular patch of vegetation using a depth-averaged two-dimensional numerical model which is capable of simulating flow structure in vegetated open channel. In order to account for vegetation effect, drag force terms are included in governing equations. Numerical simulations are conducted with various solid volume fractions (SVF). Flow passes through a circular patch and low velocity region, which is called wake region, is formed downstream of the patch. When SVF is larger than 0.08, a recirculation is observed. The location of the recirculation is moved further downstream as SVF decreases. Von-$K{\acute{a}}rm{\acute{a}}n$ vortex street is developed beyond the wake region due to interaction between two shear layers induced by a circular patch of vegetation. The vortex is developed as SVF is larger than 0.08, and the location of the vortex is consistent with the maximum of turbulence kinetic energy. The location of the peak of turbulence kinetic energy is moved further downstream as SVF decreases.
Keywords
open channel; vegetation; shear layer; vortex; two-dimensional numerical model;
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Times Cited By KSCI : 2  (Citation Analysis)
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