5.6 Velocity vectors from the results of Ebersole and Dalrymple for a wave
angle of 30 degrees. Scale for velocity vectors is 1 inch = 2.87 m/sec.
Source: Ebersole and Dalrymple (1979) 72
5.7 Velocity vectors obtained from the present model using the same input
conditions as for Ebersole and Dalrymple 73
5.8 Mean water surface elevation contours showing that the water surface is
lower above the trough. Values indicated are in millimeters 74
5.9 Depth contours in meters for the case of a bar with a gap 75
5.10 Velocity vectors for the case of waves over a bar with a gap. Dashed
lines indicate depth contours. Grid spacing equal to 10 meters 75
5.11 Depth contours for the case of normally incident waves upon a shoal.
Grid spacing is .05 meters. Contour interval is .02 meters 77
5.12 Velocity vectors for the case of waves breaking upon a shoal 78
5.13 Maximum velocity across the top of a shoal versus incident wave height
for waves over a shoal on a plane beach. Incident wave height less than
9.1 centimeters are non-breaking waves. Incident wave heights greater
than 9.1 centimeters produced waves breaking over the shoal 79
5.14 Position of the groin in relation to the grid rows and columns 80
5.15 Results for the numerical model of Liu and Mei (1975). Deepwater
wave height equal to 1 meter, deepwater wave angle equal to 45 degrees.
Source: Liu and Mei (1975) 83
5.16 Results from the present numerical model using the same conditions as
were used by Liu and Mei. Offshore boundary condition of constant wa
ter surface level which precludes tangential flow at the offshore boundary. 84
5.17 Results from the present numerical model using the same conditions as
were used by Liu and Mei. Offshore boundary condition of no on-offshore
flow. Grid spacing equal to 20 meters 85
5.18 Experimental set-up for the tests conducted by Hales (1980). Source:
Hales (1980) 86
5.19 Experimental measurements of the mid-depth averaged velocities obtain
by Hales. Measurements at one foot intervals. Source: Hales (1980). . 87
5.20 Rip-current velocities adjacent to the down wave side of the jetty. Com
parison of experimental and numerical results 88
5.21 Velocity vectors of the currents obtained numerically for the same con
ditions as for the Hales experiment. Grid spacing equal to one foot. . 89
5.22 Definition sketch of grids for the case of a shore parallel breakwater. . 90
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