Abstract
The large-scale ecological and environmental impact of coastal
canopies is tightly limited by the exchange of water across their
boundaries. In coastal environments, where the flow is typically
wave-dominated, vertical mixing is believed to be the dominant
process controlling residence time (Tres). Recent experiments
of wave-driven flows over rough boundaries, however,
have revealed the generation of a strong onshore mean current
(up to 50% of the orbital velocity far above the canopy) near the
canopy top. It is therefore imperative to understand that these
two processes, i.e. horizontal advection and vertical mixing,
can control residence time in coastal canopies. Through consideration
of a Peclet number (the ratio of diffusive to advective
time scales), this study presents a framework for quantitative
prediction of residence time in these environments. Results
reveal that Pe depends heavily on wave and canopy properties
and may vary significantly in real coastal canopies. Quantitative
predictions for residence time in the limit of Pe 1 (mixingdominated
exchange) and Pe 1 (advection-dominated exchange)
are presented. For Pe ∼ O(1), characterization of each
process will be necessary in describing residence time in these
systems.
canopies is tightly limited by the exchange of water across their
boundaries. In coastal environments, where the flow is typically
wave-dominated, vertical mixing is believed to be the dominant
process controlling residence time (Tres). Recent experiments
of wave-driven flows over rough boundaries, however,
have revealed the generation of a strong onshore mean current
(up to 50% of the orbital velocity far above the canopy) near the
canopy top. It is therefore imperative to understand that these
two processes, i.e. horizontal advection and vertical mixing,
can control residence time in coastal canopies. Through consideration
of a Peclet number (the ratio of diffusive to advective
time scales), this study presents a framework for quantitative
prediction of residence time in these environments. Results
reveal that Pe depends heavily on wave and canopy properties
and may vary significantly in real coastal canopies. Quantitative
predictions for residence time in the limit of Pe 1 (mixingdominated
exchange) and Pe 1 (advection-dominated exchange)
are presented. For Pe ∼ O(1), characterization of each
process will be necessary in describing residence time in these
systems.
| Original language | English |
|---|---|
| Title of host publication | Proceedings of the 20th Australasian Fluid Mechanics Conference |
| Publisher | Australasian Fluid Mechanics Society |
| ISBN (Electronic) | 9781740523776 |
| ISBN (Print) | 978-1-74052-377-6 |
| Publication status | Published - 5 Dec 2016 |
| Event | 20th Australasian Fluid Mechanics Conference - University of Western Australia, Perth, Australia Duration: 5 Dec 2016 → 8 Dec 2016 Conference number: 20 http://www.afms.org.au/20AFMC/ |
Conference
| Conference | 20th Australasian Fluid Mechanics Conference |
|---|---|
| Abbreviated title | AFMC |
| Country/Territory | Australia |
| City | Perth |
| Period | 5/12/16 → 8/12/16 |
| Internet address |