Page 183 - Fundamentals of Ocean Renewable Energy Generating Electricity From The Sea

172 Fundamentals of Ocean Renewable Energy

FIG. 7.10 ADCP transect at peak ebb through an island wake in the Firth of Forth, Scotland.
Contours are u, and vectors v and w. Each time slice took around 10 min to record using a
300 kHz hull-mounted ADCP, and each slice is located at a different distance downstream from
the (50 m wide) island that generates the wake: (A) 125 m downstream, and (b) 75 m downstream.
(Reproduced from S.P. Neill, A.J. Elliott, In situ measurements of spring-neap variations to
unsteady island wake development in the Firth of Forth, Scotland, Estuar. Coast. Shelf Sci. 60 (2)
(2004) 229 –239.)

large number of inexpensive drogues than to track a few expensive buoys.
For longer-term deployments, or better funded projects, it may be desirable
to release drogues that have an internal position logging system, or which
communicate their position via satellite communication. Additional sensors can
also be incorporated with such buoys to record other variables, for example,
temperature. A thorough discussion of drogues in the marine environment is
provided by Joseph [13].