Behavior determination of rigid vegetation effect on flow dynamics in open channels using CFD technology

Year 2025, Volume: 6 Issue: 1, 34 - 41, 29.06.2025

Mahmut Aydoğdu

https://doi.org/10.46572/naturengs.1682946

Abstract

In recent years, computational fluid dynamics software has significantly contributed to the literature on flow characteristics and turbulent solutions in open channel flows. In this study, two vegetation patch arrangements underwent numerical simulation using the Reynolds Stress Model in Ansys-Fluent software. The flow dynamics of the two cases were compared, and the responses of vegetation patches under subcritical flow conditions were investigated. First, the model was validated and then utilized for numerical simulation. It was observed that more effective velocity reduction occurred in the vegetation patch region and immediately downstream of the patches. While the vegetation patch in Case-1
reduced the flow velocity by 57% compared to the flow velocity at the channel entrance, it remained at 52% for Case-2. The depth-averaged vertical velocity distribution at points P1 and P2 showed lower values downstream for Case-2. Regarding the effect in the downstream region, the turbulence area in Case-2 was narrower compared to Case-1, with turbulent kinetic energy values greater than 0 observed in the channel center. While the energy dissipation percentage was 30% for Case-1, approximately 43% was achieved in Case-2. These results strongly support the feasibility reports with visuals and big data opportunities of CFD sampling before field applications.

Keywords

CFD , rigid vegetation patch , open-channel , energy dissipation , turbulent , kinetic energy

Ethical Statement

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Supporting Institution

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Thanks

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