Wave-induced velocities inside a model seagrass bed
Laboratory measurements reveal the flow structure within and above a model seagrass meadow (dynamically similar to Zostera marina) forced by progressive waves. Despite being driven by purely oscillatory flow, a mean current in the direction of wave propagation is generated within the meadow. This me...
| Main Authors: | , , , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
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American Geophysical Union
2011
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| Online Access: | http://hdl.handle.net/1721.1/66187 |
| _version_ | 1811077531811446784 |
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| author | Luhar, Mitul Coutu, Sylvain Infantes, Eduardo Fox, Samantha R. Nepf, Heidi |
| author2 | Massachusetts Institute of Technology. Department of Civil and Environmental Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Civil and Environmental Engineering Luhar, Mitul Coutu, Sylvain Infantes, Eduardo Fox, Samantha R. Nepf, Heidi |
| author_sort | Luhar, Mitul |
| collection | MIT |
| description | Laboratory measurements reveal the flow structure within and above a model seagrass meadow (dynamically similar to Zostera marina) forced by progressive waves. Despite being driven by purely oscillatory flow, a mean current in the direction of wave propagation is generated within the meadow. This mean current is forced by a nonzero wave stress, similar to the streaming observed in wave boundary layers. The measured mean current is roughly four times that predicted by laminar boundary layer theory, with magnitudes as high as 38% of the near-bed orbital velocity. A simple theoretical model is developed to predict the magnitude of this mean current based on the energy dissipated within the meadow. Unlike unidirectional flow, which can be significantly damped within a meadow, the in-canopy orbital velocity is not significantly damped. Consistent with previous studies, the reduction of in-canopy velocity is a function of the ratio of orbital excursion and blade spacing. |
| first_indexed | 2024-09-23T10:44:31Z |
| format | Article |
| id | mit-1721.1/66187 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T10:44:31Z |
| publishDate | 2011 |
| publisher | American Geophysical Union |
| record_format | dspace |
| spelling | mit-1721.1/661872022-09-27T14:39:45Z Wave-induced velocities inside a model seagrass bed Luhar, Mitul Coutu, Sylvain Infantes, Eduardo Fox, Samantha R. Nepf, Heidi Massachusetts Institute of Technology. Department of Civil and Environmental Engineering Nepf, Heidi Luhar, Mitul Fox, Samantha R. Nepf, Heidi Laboratory measurements reveal the flow structure within and above a model seagrass meadow (dynamically similar to Zostera marina) forced by progressive waves. Despite being driven by purely oscillatory flow, a mean current in the direction of wave propagation is generated within the meadow. This mean current is forced by a nonzero wave stress, similar to the streaming observed in wave boundary layers. The measured mean current is roughly four times that predicted by laminar boundary layer theory, with magnitudes as high as 38% of the near-bed orbital velocity. A simple theoretical model is developed to predict the magnitude of this mean current based on the energy dissipated within the meadow. Unlike unidirectional flow, which can be significantly damped within a meadow, the in-canopy orbital velocity is not significantly damped. Consistent with previous studies, the reduction of in-canopy velocity is a function of the ratio of orbital excursion and blade spacing. National Science Foundation (U.S.) (Grant OCE 0751358) Spain. Ministerio de Ciencia e Innovación (MICINN) (FPI scholarship program BES‐2006‐12850) 2011-10-05T16:40:04Z 2011-10-05T16:40:04Z 2010-12 2010-04 Article http://purl.org/eprint/type/JournalArticle 0148–0227 http://hdl.handle.net/1721.1/66187 Luhar, Mitul et al. “Wave-induced velocities inside a model seagrass bed.” J. Geophys. Res. 115.C12 (2010): C12005. Copyright 2010 by the American Geophysical Union en_US http://dx.doi.org/10.1029/2010jc006345 Journal of geophysical research. Oceans Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Geophysical Union MIT web domain |
| spellingShingle | Luhar, Mitul Coutu, Sylvain Infantes, Eduardo Fox, Samantha R. Nepf, Heidi Wave-induced velocities inside a model seagrass bed |
| title | Wave-induced velocities inside a model seagrass bed |
| title_full | Wave-induced velocities inside a model seagrass bed |
| title_fullStr | Wave-induced velocities inside a model seagrass bed |
| title_full_unstemmed | Wave-induced velocities inside a model seagrass bed |
| title_short | Wave-induced velocities inside a model seagrass bed |
| title_sort | wave induced velocities inside a model seagrass bed |
| url | http://hdl.handle.net/1721.1/66187 |
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