Turbulence and Bedload Transport in Submerged Vegetation Canopies
Name
Water Resources Research - 2024 - Zhao - Turbulence and Bedload Transport in Submerged Vegetation Canopies.pdf
Description
Published version
Size
1.19 MB
Format
Adobe PDF
Checksum (MD5)
868e1aab106c49d2e9022d0b308038d0
Author(s)
Zhao, Tian
Nepf, Heidi
Date Issued
December 13, 2024
Journal
Water Resources Research
Publisher
American Geophysical Union
Citation
Zhao, T., & Nepf, H. (2024). Turbulence and bedload transport in submerged vegetation canopies. Water Resources Research, 60, e2024WR037694.
Version
Final published version
Abstract
Using a constant channel velocity, , flume experiments investigated how canopy density (, with canopy frontal area per unit volume , and canopy height ) and submergence ratio (, with the flow depth) impacted near‐bed velocity, turbulence, and bedload transport within a submerged canopy of rigid model vegetation. For < 2, the near‐bed turbulent kinetic energy (TKE) was predominantly stem‐generated. As increased, both the near‐bed TKE and bedload transport rate () increased. For > 2, the near‐bed TKE was insensitive to and , because of a trade‐off between decreasing stem‐generated turbulence and increasing canopy‐shear‐generated turbulence, as and increased. However, the near‐bed velocity declined with increasing and , such that, even with a constant TKE, also declined. These trends highlight that both TKE and velocity were important in controlling bedload transport. Models to predict velocity, TKE, and bedload transport were developed and validated with measurements. The models were then used to explore conditions more relevant to the field, specifically with constant energy slope () and flexible vegetation. For a constant energy slope, increased as decreased and as increased, which in turn influenced the in‐canopy velocity and TKE. The highest occurred with the greatest and smallest , corresponding to the highest and greatest contribution of canopy‐shear‐generated turbulence, reflecting the importance of canopy‐shear‐generated turbulence in submerged canopies. The lowest occurred with smallest and highest , corresponding to the smallest and least contribution of canopy‐shear‐generated turbulence.
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1029/2024WR037694
