Form Approved
REPORT DOCUMENTATION PAGE
OMB No. 0704-0188
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1. REPORT DATE (DD-MM-YYYY)
2. REPORT TYPE
3. DATES COVERED (From - To)
September 2002
Final report
4. TITLE AND SUBTITLE
5a. CONTRACT NUMBER
5b. GRANT NUMBER
Physical Model Study of Wave Diffraction-Refraction at an Idealized Inlet
5c. PROGRAM ELEMENT NUMBER
6. AUTHOR(S)
5d. PROJECT NUMBER
William C. Seabergh, William R. Curtis, Leonette J. Thomas, Kent K. Hathaway
5e. TASK NUMBER
5f. WORK UNIT NUMBER
WU32935
7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) AND ADDRESS(ES)
8. PERFORMING ORGANIZATION REPORT
NUMBER
U.S. Army Engineer Research and Development Center
ERDC/CHL TR-02-27
3909 Halls Ferry Road
Vicksburg, MS 39180-6199
9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES)
10. SPONSOR/MONITOR'S ACRONYM(S)
U.S. Army Corps of Engineers
Washington, DC 20314-1000
11. SPONSOR/MONITOR'S REPORT
NUMBER(S)
12. DISTRIBUTION / AVAILABILITY STATEMENT
Approved for public release, distribution is unlimited.
13. SUPPLEMENTARY NOTES
A CD containing analyzed ASCII text data and model bathymetry obtained from the model configurations studied accompanies this report.
14. ABSTRACT
This physical model study of wave refraction-diffraction at structures typically present at coastal inlets was conducted to provide data
sets that would aid in the calibration and verification of numerical wave models. The study was performed in the Coastal Inlet Research
Program's (CIRP) idealized inlet experimental basin at the U.S. Army Engineer Research and Development Center (ERDC), Coastal and
Safe navigation, sediment transport into navigation channels, and shoreline erosion are all concerns at coastal inlets and are related to the
transformation of waves as they change direction and height due to complex bathymetry and coastal inlet structures. The idealized inlet
physical model, created for inlet studies, provided a facility in which to make wave measurements of height and direction in enough detail
to document wave diffraction and refraction. Measurements of wave information included use of capacitive wave rods for wave height,
acoustic-Doppler velocity sensors for wave direction, and new video-based wave direction measurement system.
Four idealized structural configurations were examined with two irregular waves, 0.8 sec, 0.2 ft (6.1 cm), and 1.6 sec, 0.15 ft (4.6 cm),
and one regular wave, 0.8 sec, 0.15 ft (4.6 cm). Structure 1 consisted of a shore-parallel breakwater with the wave generator creating shore-
normal and 20-deg-angle waves. Structure 2 was a typical dogleg jetty with shore-normal and 20-deg-angle waves. Structure 3 was an
unjettied inlet but included flood currents. Structure 4 had parallel jetties at the inlet. Structures 3 and 4 were concerned with wave
transportation into the bay. A total of 30 wave gauges were used to acquire data with 20 gauges placed on two movable racks for
deployment into specified gauge arrangements. This study also introduced the use of a new technique for acquiring video-based
measurements of wave angle, the Coastal Inlets Imaging System (CIIS).
15. SUBJECT TERMS
Inlet
Shoaling
Wave refraction
Jetty
Wave diffraction
Model study
Wave direction measurement
16. SECURITY CLASSIFICATION OF:
17. LIMITATION
18. NUMBER
19a. NAME OF RESPONSIBLE PERSON
OF ABSTRACT
OF PAGES
a. REPORT
b. ABSTRACT
c. THIS PAGE
19b. TELEPHONE NUMBER (include area
code)
418
UNCLASSIFIED
UNCLASSIFIED
UNCLASSIFIED
Standard Form 298 (Rev. 8-98)
Prescribed by ANSI Std. 239.18