Breakwater Gap Wave Diffraction: an Experimental and Numerical Study
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 113, Issue 1
Abstract
Breakwater gap configurations with gap‐to‐wavelength (B/L) ratios of 1.64, 1.41, 1.20, 1.00, 0.75, and 0.50 are investigated, both experimentally (using close‐range photogrammetry) and numerically (using finite and infinite elements). The experimental results, when compared to the finite element and available analytical results, show that: (1) The measured wave heights in the shadow zones (those regions sheltered by the breakwater arms) tend to be larger than predicted theoretically due to the combined effect of secondary waves generated at the breakwater tips and wave orthogonal spreading near the gap centerline (and subsequent wave orthogonal bunching in the shadow zones) caused by wave steepness differences along the crests; and (2) the wave heights outside the shadow zones tend to be smaller than predicted theoretically, again due to wave orthogonal spreading caused by the greater steepness of waves near the gap centerline. The results suggest that linear theory provides conservative wave height estimates outside the shadow zone, but underestimates wave heights in the shadow zone.
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Published In
Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 113 • Issue 1 • January 1987
Pages: 1 - 21
Copyright
Copyright © 1987 ASCE.
History
Published online: Jan 1, 1987
Published in print: Jan 1987
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