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http://dx.doi.org/10.9765/KSCOE.2020.32.4.203

Spatial Variation of Diffracting Wave Amplitudes on the Front and Lee Sides of the Semi-Infinite Breakwater  

Jung, Jae-Sang (Rural Research Institute, Korea Rural Community Corporation)
Lee, Changhoon (Dept. of Civil and Environ. Eng., Sejong Univ.)
Publication Information
Journal of Korean Society of Coastal and Ocean Engineers / v.32, no.4, 2020 , pp. 203-210 More about this Journal
Abstract
Spatial variation of diffracting wave amplitudes along a semi-infinite breakwater is investigated using the analytical solution of Penney and Price (1952) for wave diffraction. On the front side of the breakwater, the fluctuation of wave amplitudes due to diffracting waves would cause a wave force greater than that of superposed incident and reflected waves. The diffracting wave phase varies in circular shape from the breakwater tip of (x, y) = (0, 0) whereas the incident and reflected wave phases vary in planar shape. So, the total wave amplitude of the incident (or reflected) waves and the diffracting waves would fluctuate at a position away from the energy discontinuity line. The position (x, y) = (0, y) on the front and lee sides of the breakwater is at a distance y(π/2 - β) of the point on the energy discontinuity line along the diffracting wave crest line. The degree of reduction of the diffraction wave energy is proportional to the distance from the point on the energy discontinuity line along the diffracting wave crest line. Therefore, the diffracting wave amplitudes on the front and lee sides of the breakwater would be inversely proportional to the square root of y(π/2 - β).
Keywords
semi-infinite breakwater; diffracting wave; analytical solution; theoretical investigation;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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