Shore-parallel breakwater

Simulation of wave reflection, refraction, strong diffraction, shoaring, and breaking

Model simulated wave height contours (in cm) for the shore-parallel breakwater.

On the top and bottom sides as well as the two sides of the breakwater, the total reflection boundary condition was specified.  The numerical study domain stopped at a water depth of 0.5 cm, which is sufficient to check for wave breaking.  The radiation boundary condition was specified at the left and right sides of the study domain.

The incident waves (wave height = 2 cm, period = 1.2 sec, normal incident) were totally reflected by the shore-parallel breakwater.  Behind the breakwater, there is strong wave diffraction (see the wave vectors between 2.0 < x < 4.5 m and  1.5 m < y < 4 m as well as the wave crest lines in the next figure).  Because waves behind the breakwater were coming from both top (y > 5.2 m) and bottom side (y < 2.8 m), the wave vectors actually represent the vector sum of two wave sources: one from top and the other from bottom.. For details, see Maa et al. (2002).  

Model simulated wave vectors and wave crest lines showing

strong wave diffraction behind the shore-parallel breakwater.