Journal article
A One-Dimensional Model for Turbulent Mixing in the Benthic Biolayer of Stream and Coastal Sediments
Water resources research, Vol.56(12), p.n/a
12/2020
DOI: 10.1029/2019WR026822
Abstract
In this paper, we develop and validate a rigorous modeling framework, based on Duhamel's Theorem, for the unsteady one-dimensional vertical transport of a solute across a flat sediment-water interface (SWI) and through the benthic biolayer of a turbulent stream. The modeling framework is novel in capturing the two-way coupling between evolving solute concentrations above and below the SWI and in allowing for a depth-varying diffusivity. Three diffusivity profiles within the sediment (constant, exponentially decaying, and a hybrid model) are evaluated against an extensive set of previously published laboratory measurements of turbulent mass transfer across the SWI. The exponential diffusivity profile best represents experimental observations and its reference diffusivity scales with the permeability Reynolds number, a dimensionless measure of turbulence at the SWI. The depth over which turbulence-enhanced diffusivity decays is of the order of centimeters and comparable to the thickness of the benthic biolayer. Thus, turbulent mixing across the SWI may serve as a universal transport mechanism, supplying the nutrient and energy fluxes needed to sustain microbial growth, and nutrient processing, in the benthic biolayer of stream and coastal sediments.
Details
- Title: Subtitle
- A One-Dimensional Model for Turbulent Mixing in the Benthic Biolayer of Stream and Coastal Sediments
- Creators
- Stanley B. Grant - Virginia TechJesus D. Gomez-Velez - Vanderbilt UniversityMarco Ghisalberti - The University of Western AustraliaIan Guymer - University of SheffieldFulvio Boano - Polytechnic University of TurinKevin Roche - Boise State UniversityJudson Harvey - United States Geological Survey
- Resource Type
- Journal article
- Publication Details
- Water resources research, Vol.56(12), p.n/a
- DOI
- 10.1029/2019WR026822
- ISSN
- 0043-1397
- eISSN
- 1944-7973
- Publisher
- Amer Geophysical Union
- Number of pages
- 17
- Grant note
- EP/P012027/1 / EPSRC; UK Research & Innovation (UKRI); Engineering & Physical Sciences Research Council (EPSRC) EP/P012027/1 / UK EPSRC Established Career Fellowship; UK Research & Innovation (UKRI); Engineering & Physical Sciences Research Council (EPSRC) Fulbright program U.S. Geological Survey Water Availability and Use Science Program 1840504; 2021015; EAR 1830172 / U.S. National Science Foundation; National Science Foundation (NSF) U.S. Department of Energy, Office of Biological and Environmental Research (BER), as part of BER's Subsurface Biogeochemistry Research Program (SBR); United States Department of Energy (DOE) DP120102500 / Australian Research Council Virginia Tech's ICTAS EFO Opportunity Seed Investment Grant MRP-17-455083 / UC Office of the President Multicampus Research Program Initiative award 1840504 / Directorate For Engineering; Div Of Engineering Education and Centers; National Science Foundation (NSF); NSF - Directorate for Engineering (ENG)
- Language
- English
- Date published
- 12/2020
- Academic Unit
- Civil and Environmental Engineering
- Record Identifier
- 9984962533402771
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