A Case Study of the Generation of Irregular Sea Waves

Abstract

This article describes the generation methods of irregular sea waves specified by its spectrum. It will describe the difference between the small equal frequency division method and the energy equivalence frequency division method. In the latter method, it is shown to completely generate a stationary irregular wave in an engineering regard. The theoretical iteration period of the time histories generated by the method is also obtained by using a symbolic computation. Finally, experimental results of the generation of sea waves spectra are presented. The spectrum of the revolution of the AC servomotor driven by the energy equivalence frequency division method is obtained. The good agreement between the measured and calculated spectra is shown.

Keywords

Energy equivalence irregular sea waves iteration period spectrum

Get full access to this article

View all access options for this article.

References

Coastal Engineering Research Center , 1984, Shore Protection Manual, Fourth Edition: US Army Coastal Engineering Research Centre, Government Printing Office, Washington DC.

Elishakoff, I. , 1979, "Simulation of space-random fields for solution of stochastic boundary value problem," J. Acoustical Society of America 61, 399-403.

Hasselmann, K. , Barnett, T.P. , Bouws, E. , Carlson, H. , Cartwright, D.E. , Enke, K. , Ewing, J.A. , Gienapp, H. , Hasselmann, D.E. , Kruseman, P. , Meerburgh, A. , Muller, P. , Olbers, D.J. , Richter, K. , Sell, W. , and Walden, H. , 1973, "Measurements of wind-wave growth and swell decay during the Joint North Sea Wave Project (JONSWAP)," Deutsche Hydrograph Z. A8(12).

Heck, A. , 1993, Introduction to Maple, Springer-Verlag , New York.

Huang, N.E. , Tung, C. , and Long, S.R. , 1990, "Wave spectra," Ocean Engineering Science, The Sea 9(Pt. A), 197-237.

Longuet-Higgins, M.S. , 1952, "On the statistical distribution of the heights of sea waves," Journal of Marine Research 11, 245-266.

Mitsuyasu, W. , 1970, "Development of spectra ofwmd and waves (2)," in Proceedings of the 17th Coastal Engineering Conference , Tokyo, pp. 1-7 (in Japanese).

Nagai, Y. , 1972, "Calculation of refraction and diffraction of irregular sea waves," Report of the Port and Harbour Research Institute 11(2), 47-119.

Pierson, W.J. and Moskowitz, L. , 1964, "A proposed spectral form for fully developed wind sea based on the similarity theory of S. A. Kitaigorodskii," J. Geophysical Res. 69, 5181-5190.

10.

Shinozuka, M. and Deodatis, G. , 1996, "Simulation of multi-dimensional Gaussian stochastic fields by spectral representation," Applied Mechanics Reviews 19(1), 29-53.

11.

Takayama, T. and Hiraishi, T. , 1989, "Reproducibility of directional random waves in laboratory wave simulation," Report of the Port and Harbour Research Institute 28(4), 3-24.

12.

Wiegel, R.L. , 1964, Oceanographical Engineering, Prentice Hall, Englewood Cliffs, NJ.