TR-08-13

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ERDC/CHL TR-08-13			File:TR-08-13 02.jpg
			Coastal Inlets Research Program CMS-Wave: A Nearshore Spectral Wave Processes Model for Coastal Inlets and Navigation Projects
Coastal and Hydraulics Laboratory			Lihwa Lin, Zeki Demirbilek, Hajime Mase, Jinhai Zheng, and Fumihiko Yamada	August 2008
			File:TR-08-13 03 16.png
			Approved for public release; distribution is unlimited.

Coastal Inlets Research Program	ERDC/CHL TR-08-13 August 2008
CMS-Wave: A Nearshore Spectral Wave Processes Model for Coastal Inlets and Navigation Projects
Lihwa Lin and Zeki Demirbilek U.S. Army Engineer Research and Development Center Coastal and Hydraulics Laboratory 3909 Halls Ferry Road Vicksburg, MS 39180-6199, USA Hajime Mase Disaster Prevention Research Institute Kyoto University Gokasho, Uji, Kyoto, 611-0011, JAPAN Jinhai Zheng Hohai University Research Institute of Coastal and Ocean Engineering 1 Xikang Road, Nanjing, 210098, China Fumihiko Yamada Kumamato University Graduate School of Science and Technology 2-39-1, Kurokami, Kumamoto, 860-8555, JAPAN
Final report Approved for public release; distribution is unlimited Prepared forU.S. Army Corps of Engineers Washington, DC 20314-1000 Monitored byCoastal and Hydraulics Laboratory U.S. Army Engineer Research and Development Center 3909 Halls Ferry Road, Vicksburg, MS 39180-6199

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Abstract: The U.S. Army Corps of Engineers (USACE) plans, designs, constructs, and maintains jetties, breakwaters, training structures, and other types of coastal structures in support of Federal navigation projects. By means of these structures, it is common to constrain currents that can scour navigation channels, stabilize the location of channels and entrances, and provide wave protection to vessels transiting through inlets and navigation channels. Numerical wave predictions are frequently sought to guide management decisions for designing or maintaining structures and inlet channels.

The Coastal Inlets Research Program (CIRP) of the U.S. Army Engineer Research and Development Center (ERDC), Coastal and Hydraulics Laboratory (CHL), in collaboration with two universities in Japan, has developed a spectral wave transformation numerical model to address needs of USACE navigation projects. The model is called CMS-Wave and is part of Coastal Modeling System (CMS) developed in the CIRP. The CMS is a suite of coupled models operated in the Surface-water Modeling System (SMS), which is an interactive and comprehensive graphical user interface environment for preparing model input, running models, and viewing and analyzing results. CMS-Wave is designed for accurate and reliable representation of wave processes affecting operation and maintenance of coastal inlet structures in navigation projects, as well as in risk and reliability assessment of shipping in inlets and harbors. Important wave processes at coastal inlets are diffraction, refraction, reflection, wave breaking, dissipation mechanisms, and the wave-current interaction. The effect of locally generated wind can also be significant during wave propagation at inlets.

This report provides information on CMS-Wave theory, numerical implementation, and SMS interface, and a set of examples demonstrating the model’s application. Examples given in this report demonstrate CMS-Wave applicability for storm-damage assessment, modification to jetties including jetty extensions, jetty breaching, addition of spurs to inlet jetties, and planning and design of nearshore reefs and barrier islands to protect beaches and promote navigation reliability.

DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR.

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Contents

Figures and Tables		v
Preface		ix

1	Introduction	1
	Overview	1
	Review of wave processes at coastal inlets	2
	New features added to CMS-Wave	7

2	Model Description	9
	Wave-action balance equation with diffraction	9
	Wave diffraction	9
	Wave-current interaction	10
	Wave reflection	11
	Wave breaking formulas	12
	Extended Goda formula	13
	Extended Miche formula	14
	Battjes and Janssen formula	15
	Chawla and Kirby formula	16
	Wind forcing and whitecapping dissipation	16
	Wind input function	16
	Whitecapping dissipation function	17
	Wave generation with arbitrary wind direction	18
	Bottom friction loss	18
	Wave runup	19
	Wave transmission and overtopping at structures	21
	Grid nesting	21
	Variable-rectangular-cell grid	22
	Non-linear wave-wave interaction	22
	Fast-mode calculation	23

3	CMS-Wave Interface	24
	CMS-Wave files	24
	Components of CMS-Wave interface	29

4	Model Validation	42
	Case 1: Wave shoaling and breaking around an idealized inlet	42
	Case 2: Waves breaking on plane beach	49
	Case 3: Wave runup on impermeable uniform slope	50
	Case 4: Wave diffraction at breakwater and breakwater gap	54
	Case 5: Wave generation in fetch-limited condition	60
	Case 6: Wave generation in bays	61
	Case 7: Large waves at Mouth of Columbia River	67
	Case 8: Wave transformation in fast mode and variable-rectangular-cell grid	74
	Case 9: Wave transformation over complicated bathymetry with strong nearshore current	79
	Extended Miche formula	81
	Extended Goda formula	84
	Battjes and Jansen formula	87
	Chawla and Kirby formula	90

5	Field Applications	96
	Matagorda Bay	96
	Grays Harbor Entrance	99
	Southeast Oahu coast	106

References	111
Appendix A: CMA-Wave Input File Formats	117

Report Documentation Page

Figures and Tables

Figures

Figure 1. Files used in CMS-Wave simulation	25
Figure 2. CMS-Wave menu	30
Figure 3. Creating a grid	32
Figure 4. Map ->2D Grid Dialog	33
Figure 5. CMS-Wave Cell Attributes dialog	35
Figure 6. Spectral energy dialog for spectra visualization and generation	36
Figure 7. CMS-Wave Model Control dialog	38
Figure 8. Selecting wave spectra	39
Figure 9. Project Explorer with solution read in	40
Figure 10. Idealized inlet and instrument locations	43
Figure 11. Input current fields for Runs 5-8, Runs 9-12, and save stations	46
Figure 12. Measured and calculated current speeds along channel centerline, Runs 5-8	46
Figure 13. Measured and calculated current speeds along channel centerline, Runs 9-12	47
Figure 14. Measured and calculated wave heights along channel centerline, Runs 1-4	47
Figure 15. Measured and calculated wave heights along channel centerline, Runs 5-8	48
Figure 16. Measured and calculated wave heights along channel centerline, Runs 9-12	48
Figure 17. Input current and wave setup fields with save stations for Exp. 4	51
Figure 18. Measured and calculated wave heights, Exp. 4-7	52
Figure 19. Measured and calculated 2% exceedance wave runup	53
Figure 20. Wave diffraction diagram and calculated k’ for a breakwater	55
Figure 21. Calculated wave vectors and K, 0 deg incident wave	55
Figure 22. Calculated wave vectors and K, -45 deg incident wave	56
Figure 23. Calculated wave vectors and K, 45 deg incident wave	56
Figure 24. Wave diffraction diagram and calculated K for a gap, B = 2L	57
Figure 25. Wave diffraction diagram and calculated K for a gap, B = L	58
Figure 26. Calculated wave vectors and K for gap B = 2L, 0 deg incident wave	58
Figure 27. Calculated wave vectors and K for gap B = 2L, -45 deg incident wave	59
Figure 28. Calculated wave vectors and K for gap B = 2L, 45 deg incident wave	59
Figure 29. Comparison of calculated wave generation and SMB curves	61
Figure 30. Modeling grid domain for Rich Passage and wave gauge location	62
Figure 31. Input current and calculated wave fields at 00:40 GMT, 29 March 2005	63
Figure 32. Input current and calculated wave fields at 19:20 GMT, 29 March 2005	64
Figure 33. Model domain and calculated wave field at 12:00 GMT, 27 February 1993	66
Figure 34. Measured and calculated spectra at TSL, 12:00 GMT, 27 February 1993	66
Figure 35. Wave model domain and directional wave data-collection stations	68
Figure 36. Wave and wind data collected at Buoy 46029, sta 4 and 5	68
Figure 37. Calculated waves with and without wind input, 10:00 GMT, 7 August 2005	70
Figure 38. Calculated waves with and without wind input, 18:00 GMT, 9 September 2005	70
Figure 39. Measured and calculated spectra at sta 1, 10:00 GMT, 7 August 2005	70
Figure 40. Measured and calculated spectra at sta 2, 10:00 GMT, 7 August 2005	71
Figure 41. Measured and calculated spectra at sta 3, 10:00 GMT, 7 August 2005	71
Figure 42. Measured and calculated spectra at sta 4, 10:00 GMT, 7 August 2005	71
Figure 43. Measured and calculated spectra at sta 5, 10:00 GMT, 7 August 2005	72
Figure 44. Measured and calculated spectra at sta 1, 00:00 GMT, 30 August 2005	72
Figure 45. Measured and calculated spectra at sta 2, 00:00 GMT, 30 August 2005	72
Figure 46. Measured and calculated spectra at sta 3, 00:00 GMT, 30 August 2005	73
Figure 47. Measured and calculated spectra at sta 4, 00:00 GMT, 30 August 2005	73
Figure 48. Measured and calculated spectra at sta 5, 00:00 GMT, 30 August 2005	73
Figure 49. Measured and calculated spectra at sta 2, 18:00 GMT, 9 September 2005	74
Figure 50. Measured and calculated spectra at sta 3, 18:00 GMT, 9 September 2005	74
Figure 51. CMS-Wave variable-cell grid and five monitoring stations at MCR	76
Figure 52. Calculated wave fields in the standard mode, 12:00 GMT, 14 December 2001	76
Figure 53. Calculated wave fields in the fast mode, 12:00 GMT, 14 December 2001	77
Figure 54. Calculated wave fields in the fast mode, 13:00 GMT, 4 February 2006	77
Figure 55. Bathymetry in meters and locations of wave and current meters	80
Figure 56. Measured current and normalized wave height contours for directional and unidirectional incident waves	80
Figure 57. Calculated wave height contours for directional incident waves without current and with current by the Extended Miche formula with coefficient of 0.14	81
Figure 58. Calculated wave height contours for unidirectional incident waves without current and with current by the Extended Miche formula with coefficient of 0.14	82
Figure 59. Measured versus calculated wave heights for directional and unidirectional incident waves with the Extended Miche formula	83
Figure 60. Normalized wave height comparisons of directional waves along longitudinal and transverse transects with the Extended Miche formula	83
Figure 61. Normalized wave height comparisons of unidirectional waves along longitudinal and transverse transects with the Extended Miche formula	84
Figure 62. Calculated wave height contours for directional incident waves without current and with current by the Extended Goda formula with coefficient of 0.17	85
Figure 63. Calculated wave height contours for unidirectional incident waves without current and with current by the Extended Goda formula with coefficient of 0.17	85
Figure 64. Measured versus calculated wave heights for directional and unidirectional incident waves with the Extended Goda formula	86
Figure 65. Normalized wave height comparisons of directional incident waves along longitudinal and transverse transects with the Extended Goda formula	86
Figure 66. Normalized wave height comparisons of unidirectional incident waves along longitudinal and transverse transects with the Extended Goda formula	87
Figure.67. Calculated wave height contours for directional incident waves without current and with current by the Battjes and Janssen formula	88
Figure 68. Calculated wave height contours for unidirectional waves without current and with currents by the Battjes and Janssen formula	88
Figure 69. Measured versus calculated wave heights for directional and unidirectional incident waves with the Battjes and Janssen formula	89
Figure 70. Normalized wave height comparisons of directional incident waves along longitudinal and transverse transects with the Battjes and Janssen formula	89
Figure 71. Normalized wave height comparisons of unidirectional incident waves along longitudinal and transverse transects with the Battjes and Janssen formula	90
Figure 72. Calculated wave height contours for directional incident waves without current and with current by the Chawla and Kirby formula with  of 0.6	91
Figure 73. Calculated wave height contours for directional incident waves without current and with current by the Chawla and Kirby formula with  of 1.0	91
Figure 74. Calculated wave height contours for unidirectional incident waves without current and with current by the Chawla and Kirby formula with  of 0.6	92
Figure 75. Calculated wave height contours for unidirectional incident waves without current and with current by the Chawla and Kirby formula with  of 1.0	92
Figure 76. Measured versus calculated wave heights for directional and unidirectional incident waves with the Chawla and Kirby formula	93
Figure 77. Normalized wave height comparisons of directional incident waves along longitudinal and transverse transects with the Chawla and Kirby formula	93
Figure 78. Normalized wave height comparisons of unidirectional incident waves along longitudinal and transverse transects with the Chawla and Kirby formula	94
Figure 79. Wind, tides, and wave data-collection stations in Matagorda Bay	97
Figure 80. Matagorda Bay wind and water level data, September-December 2005	98
Figure 81. Directional wave data collected at MBWAV, September-December 2005	98
Figure 82. Calculated Matagorda Bay wave field at 08:00 GMT, 24 October 2005	99
Figure 83. Wave data-collection stations at Grays Harbor	101
Figure 84. Wind and wave data from NDBC 46029 and CDIP 036, 20-31 December 2003	102
Figure 85. Calculated maximum flood current field, 19:00 GMT, 25 December 2003	103
Figure 86. Calculated maximum ebb current field, December 2003	103
Figure 87. Measured and calculated waves at HMB01, 24-28 December 2003	104
Figure 88. Measured and calculated waves at HMB02, 24-28 December 2003	104
Figure 89. Measured and calculated waves at HMB03, 24-28 December 2003	105
Figure 90. Measured and calculated waves at HMB04, 24-28 December 2003	105
Figure 91. Tide and wave data-collection stations and model domain for SEO/RSM studies	107
Figure 92. Bathymetry grid, and different bottom friction coefficient regions	108
Figure 93. Measured and calculated waves at ADV1 and ADV3, August-September 2005	109
Figure 94. Measured and calculated waves at ADV2, August-September 2005	110

Tables

Table 1. CMS-Wave simulation files	26
Table 2. CMS-Wave Menu Commands	30
Table 3. CMS-Wave Tools	31
Table 4. Spectral Parameters	37
Table 5. Incident wave parameters and current conditions	44
Table 6. Incident wave conditions	49
Table 7. Statistics of measured and calculated wave runup	53
Table 8. Comparison of measured and calculated wave height at wave Gauge LT14	64
Table 9. Coordinates of wave monitoring stations at MCR	67
Table 10. Waves in two extreme storms observed offshore of MCR at Buoy 46029	75
Table 11. Total computer runtime for two storm wave events at MCR	78
Table 12. Calculated wave height and direction, 12:00 GMT, 14 December 2001	78
Table 13. Calculated wave height and direction, 13:00 GMT, 4 February 2006	78
Table 14. Statistical mean relative errors and correlation coefficients	95
Table 15. Comparison of measured and calculated waves at MBWAV	99
Table 16. Coordinates of wave monitoring stations at Grays Harbor	101
Table 17. Coordinates of ADV stations at southeast Oahu	106

Preface

The Coastal Inlets Research Program (CIRP) is developing and supporting a phase-averaged spectral wave model for inlets and nearshore applications. The model, called CMS-Wave is part of the Coastal Modeling System (CMS) for simulating nearshore waves, flow, sediment transport, and morphology change affecting planning, design, maintenance, and reliability of federal navigation projects. This report describes the theory and numerical implementation of the CMS-Wave interface in the Surface-water Modeling System (SMS), and contains examples to demonstrate use of the model in project applications.

The CIRP is administered at the U.S. Army Engineer Research and Development Center (ERDC), Coastal and Hydraulics Laboratory (CHL) under the Navigation Systems Program for Headquarters, U.S. Army Corps of Engineers (HQUSACE). James E. Walker is HQUSACE Navigation Business Line Manager overseeing CIRP. Jeff Lillycrop, CHL, is the Technical Director for the Navigation Systems Program. Dr. Nicholas C. Kraus, Senior Scientists Group (SSG), CHL, is the CIRP Program Manager.

The mission of CIRP is to conduct applied research to improve USACE capabilities to manage federally maintained inlets, which are present on all coasts of the United States, including the Atlantic Ocean, Gulf of Mexico, Pacific Ocean, Great Lakes, and U.S. territories. CIRP objectives are to advance knowledge and provide quantitative predictive tools to (a) make management of federal coastal inlet navigation projects, principally the design, maintenance, and operation of channels and jetties, more effective and reduce the cost of dredging; and (b) preserve the adjacent beaches and estuary in a systems approach that treats the inlet, beaches, and estuary as sediment-sharing components. To achieve these objectives, CIRP is organized in work units conducting research and development in hydrodynamics; sediment transport and morphology change modeling; navigation channels and adjacent beaches; navigation channels and estuaries; inlet structures and scour; laboratory and field investigations; and technology transfer.

This report was prepared by Drs. Lihwa Lin, Coastal Engineering Branch and Zeki Demirbilek, Harbors, Entrances and Structures Branch, both of ERDC-CHL, Vicksburg, MS; Drs. Hajime Mase of Disaster Research Institute at Kyoto University, Japan, and Jinhai Zheng, visiting Scholar at Kyoto University, and Fumihiko Yamada of the Applied Coastal Research Laboratory at Kumamato University, Japan.

Work at CHL was performed under the general supervision of Mr. Edmond J. Russo, Jr., P.E., Chief of Coastal Engineering Branch, Dr. Donald L. Ward, Acting Chief of Coastal Entrances and Structures Branch, and Dr. Rose M. Kress, Chief of Navigation Division. J. Holley Messing, Coastal Engineering Branch, Navigation Division, CHL, typed the equations and format-edited the report. Mr. Thomas W. Richardson was Director, CHL, and Dr. William D. Martin was Deputy Director, CHL, during the study and preparation of this report.

COL Gary E. Johnston was Commander and Executive Director of ERDC. Dr. James R. Houston was Director of ERDC.