Boat-Wake Statistics at Jensen Beach, Florida
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 139, Issue 4
Abstract
Ship/boat wakes are identified in pressure and flow velocity records as chirp signals, which are also known as sweep signals in sonar and radar applications. A chirp is a signal in which the frequency increases or decreases with time. Wakes are analyzed using time-frequency techniques [windowed Fourier transform (WFT), wavelet transform (WT), and instantaneous frequency]. This approach allows for detecting boat wakes and studying their statistics, even in the presence of a relatively strong broad-banded wind-wave background. Time-frequency methods also open a new direction for the statistical description of wakes, which are applicable to the characterization of the wake climate (e.g., for sites with intense boat traffic). The usefulness of the time-frequency analysis on observations collected in 2010 at Jensen Beach, Florida will be demonstrated.
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Acknowledgments
The financial support of Martin County, Florida provided the writers the opportunity to conduct this study. The writers also are grateful to Tim Blankenship (P.E., M.ASCE, Coastal Systems International, Inc.) for support and fruitful discussions. Vic Adams from the Coastal and Oceanographic Engineering Laboratory, Univ. of Florida, was in charge of the logistics of the field experiment.
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Published In
Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 139 • Issue 4 • July 2013
Pages: 286 - 294
Copyright
© 2013 American Society of Civil Engineers.
History
Received: May 13, 2012
Accepted: Sep 11, 2012
Published online: Sep 14, 2012
Published in print: Jul 1, 2013
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