Ocean and Polar Research

Korea Institute of Ocean Science & Technology (한국해양과학기술원)
권호 표지
DOI QR코드

DOI QR Code

Field Measurements of Wave Directionality in Water of Finite Depth

  • Memos, Constantine (School of Civil Engineering, National Technical University of Athens) ;
  • Ziros, Athanassios (School of Civil Engineering, National Technical University of Athens)
  • Published : 2003.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

Field measurements of directional waves were carried out during the summer of 2002 at two coastal sites in water of finite depth. A couple of general purpose instruments were used employing acoustic Doppler technology. The aim of the study was to investigate the spatial behavior of the directional movement of waves as they come ashore. In total,74 tests were carried out during which sea states of low to moderate intensity were recorded. A great number of these runs displayed bimodal characteristics of the spreading function at high frequencies. It was found that in general, the frequency-integrated directional width tends to broaden as the water shoals and when refraction effects are negligible. This is attributed to wave-wave interactions that become pronounced in shallow water. The same directional width showed, also, a tendency to increase with increasing peak frequency of the sea state spectrum. The behavior of the kurtosis of the spreading function was also examined. It was found that for higher frequencies this index tends to increase in wave spectra above a certain sea severity threshold.

Keywords

References

  1. Banner, M.L. 1990. Equilibrium spectra of wind waves J.Phys. Oceanogr., 20, 966-984. https://doi.org/10.1175/1520-0485(1990)020<0966:ESOWW>2.0.CO;2
  2. Banner, M.L. and I.R. Young. 1994. Modelling spectral dissipation in the evolution of wind waves-Part 1. Assessment of existing model performance. J. Phys. Oceanogr.,24, 1550-1671. https://doi.org/10.1175/1520-0485(1994)024<1550:MSDITE>2.0.CO;2
  3. Borgman, L.E. 1969. Directional spectra models for design use. Proc. Offshore Tech. Conf., 1069, 721-746.
  4. Borgman, L.E. 1984. Directional spectrum estimation for the Sxy gauges. p. 1-104. In: Tech. Rept. CERC, USAE Waterways Exper. Station, Vicksburg.
  5. Capon, J. 1969. High-resolution frequency-wavenumber spectrum analysis. Proc. IEEE, 57, 203-219.
  6. Coastal Engineering Research Center. 1985. Directional Wave Spectra using cosine-squared and cosine 2s Spreading Functions. Coast. Eng. Tech., Note-I-28, 6/85, 6 p.
  7. Collins, J.I., W-L. Chiang, and F. Wu. 1981. Refraction of directional spectra. p. 251-268. In: Proc. Conf. Directional Wave Spectra Applications. ASCE, Berkeley, CA.
  8. Donelan, M.A., J. Hamilton, and W.H. Hui. 1985. Directional spectra of wind-generated waves. Phil. Trans. Roy. Soc. London, A 315, 509-562.
  9. Gordon, L. and L. Clarke. 1999. Doppler Current Meter Wave Observations in the Near-Shore and Surf Zone. .
  10. Gordon, L. and A. Lohrmann. 2001. Near shore Doppler current meter wave spectra. Proc. Waves'01, ASCE.
  11. Hasselmann, D.E., M. Dunckel, and J.A. Ewing. 1980. Directional wave spectra observed during JONSWAP. J. Phys. Oceanogr., 13, 191-207. https://doi.org/10.1175/1520-0485(1983)013<0191:OOTDDO>2.0.CO;2
  12. Herbers, T.H.C., S. Elgar, and R.T. Guza. 1999. Directional spreading of waves in the nearshore. J. Geophys. Res., 104 (C4), 7683-7693. https://doi.org/10.1029/1998JC900092
  13. Kuik, A.J., G. Vledder, and L.H. Holthuijsen. 1988. A method for the routine analysis of pitch and roll buoy wave data. J. Phys. Oceanogr., 18, 1020-1034. https://doi.org/10.1175/1520-0485(1988)018<1020:AMFTRA>2.0.CO;2
  14. Kumar, V.S., M.C. Deo, N.M. Anand, and K.A. Kumar. 2000. Directional spread parameter at intermediate water depth. Ocean Eng., 27, 889-905. https://doi.org/10.1016/S0029-8018(99)00029-3
  15. Longuet-Higgins, M.S. 1957. The Statistical Analysis of a Random, Moving Surface. Phil. Trans. Roy. Soc. London, A 966, 321-387.
  16. Longuet-Higgins, M.S., D.E. Cartwright, and N.D. Smith. 1963. Observations of the directional spectrum of sea waves using the motions of a floating buoy. Ocean Wave Spectra, Prentice-Hall, N.J. p. 111-136.
  17. Mardia, K.V. 1972. Statistics of directional data. Academic Press, London & New York.
  18. Mitsuyasu, H., F. Tasai, T. Suhara, S. Mizuno, M. Onkusu, T. Hond, and K. Rukiiski. 1975. Observations of the directional spectrum of ocean waves using a cloverleaf buoy. J. Phys. Oceanogr., 5, 751-761.
  19. Nagai, K. 1972. Diffraction of the irregular sea due to breakwater. Coastal Eng. Japan, 15, 59-67.
  20. Nwogu, O. 1989. Maximum entropy estimation of directional wave spectra from an array of wave probes. Applied Ocean Res., 11, 176-182. https://doi.org/10.1016/0141-1187(89)90016-3
  21. Pierson, W.J., Jr., G. Neuman, and R.W. James. 1955. Practical methods for observing and forecasting ocean waves by means of wave spectra and statistics. Publ. no. 603, US Naval Hydr. Office.
  22. Van der Vlugt, A.J.M., A.J. Kuik, and L.H. Holthuijsen. 1981. The wave directional buoy under development. p. 50-60. In: Proc. Conf. Directional Wave Spectra Application Berkeley, CA, ASCE.
  23. Wang, D.W. 1992. Estimation of wave directional spreading in severe seas. Proc. 2nd Int. Offshore & Polar Eng. Conf., III, 146-153.
  24. Willebrand, J. 1975. Energy transport in a nonlinear and in homogeneous random wave field. J. Fluid Mech., 70, 113-126. https://doi.org/10.1017/S0022112075001929
  25. Young, I.R., L.A. Verhagen, and S.K. Khatri. 1996. The growth of fetch limited waves in water of finite depth. Part 3. Directional spectra. Coastal Eng., 29, 101-121. https://doi.org/10.1016/S0378-3839(96)00026-9

Cited by

  1. A simple method for obtaining wave directional spreading 2016, https://doi.org/10.1080/23249676.2016.1172270