The circular wave basin provides a means of physically modeling the nearshore
without the typical problems associated with end walls. Three different coastal
processes were examined to demonstrate the use of a spiral wavemaker in a circular
wave basin. These were longshore currents, shear waves, and groin circulation. A
beach was designed and constructed to concentrate breaking in a narrow region and
minimize wave reflection. Currents in the longshore direction were generated by both
the motion of the wavemaker and oblique wave approach. Two methods for measuring
nearshore currents were employed. First, a 3-D acoustic current meter was positioned
at various locations in the cross shore and the local radial and tangential velocities
were recorded. Second, a video camera was placed approximately 8 meters above the
wave basin to record the motion of a ball in the nearshore. The video tape was
digitized by an image processor and the motion of the ball was determined.
Measurements of nearshore circulation in the circular wave basin were used to
investigate longshore currents, shear waves, and groin circulation. Average measured
longshore current profiles in the cross shore were compared with numerical model
predictions. An analysis of the existence of shear waves in the circular wave basin
was performed by calculating longshore and cross shore current spectra. Particular
attention was focused on the low frequency end of the spectra where shear waves are
most energetic. Model groins were placed in the circular wave basin and measured
currents were compared to predicted circulation patterns. All three applications
indicated that the circular wave basin is a useful device for simulating coastal processes
in a laboratory environment. / Graduation date: 1992
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/36579 |
| Date | 14 January 1992 |
| Creators | Katzev, David H. |
| Contributors | McDougal, William G. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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