Accuracy of Low‐Order Models for Simulations of Random Ocean Waves
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 119, Issue 1
Abstract
The accuracy of low‐order time‐domain simulation techniques for modeling wave maxima, periods, and spectral bandwidths is examined in detail. The techniques are based on the direct summation of sinusoidal components, with the number of components largely dependent on the spectral bandwidth. At the lower end of bandwidths corresponding to actual ocean waves, only five to 10 components of equal amplitude are sufficient to give values that deviate by only a few percent from theoretical criteria governing random waves. At the upper end of the bandwidth range, 15–20 components at equal frequency intervals are required to give comparable accuracy. Guidelines are given for proper choices of the upper and lower spectral energy (or frequency) cutoffs. Criteria that are not satisfied by these low‐order models are identified. The significance of these criteria in actual applications and possible remedies within the framework of the present models are discussed.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Bishop, R. E. D., and Price, W. G. (1978). “On the truncation of spectra.” Int. Shipbuilding Progress, 25(281), 3–6.
2.
Cartwright, D. E., and Longuet‐Higgins, M. S. (1956). “The statistical distribution of the maxima of a random function.” Proc., Royal Society of London, London, England, A237(1209), 212–232.
3.
Chakrabarti, S. K., and Cooley, R. P. (1977). “Statistical distribution of periods and heights of ocean waves.” J. Geophysical Res., 82(9), 1363–1368.
4.
Chakrabarti, S. K. (1987). Hydrodynamics of offshore structures. Computational Mechanics Publications, Boston, Mass., 102–122.
5.
Cuong, H. T., Troesch, A. W., and Birdsall, T. G. (1982). “The generation of digital random time histories.” Oc. Engrg., 9(6), 581–588.
6.
Elgar, S., Guza, R. T., and Seymour, R. J. (1985). “Wave group statistics from numerical simulations of a random sea.” Appl. Oc. Res., 7(2), 93–96.
7.
Flower, J. O. (1981). “Probabilistic properties of a limited number of summed sinusoidal waves with reference to sea‐wave simulation and experiments.” Int. Shipbuilding Progress, 28(324), 180–190.
8.
Haver, S., and Moan, T. (1983). “On some uncertainties related to the short term stochastic modeling of ocean waves.” Appl. Oc. Res., 5(2), 93–108.
9.
Hudspeth, R. T., and Borgman, L. E. (1979). “Efficient FFT simulation of digital time sequences.” J. Engrg. Mech. Div., ASCE, 105(2), 223–235.
10.
Hurwitz, R. B., and Neal, E. (1979). “Digital simulation of a Gaussian seaway based on the random phase model.” Report No. 79/056, David W. Taylor Naval Ship R&D Center, Bethesda, Md.
11.
Kinsman, B. (1965). Wind waves—Their generation and propagation on the ocean surface. Prentice‐Hall, Inc., Englewood Cliffs, N.J., 394–396.
12.
Longuet‐Higgins, M. S. (1983). “On the joint distribution of wave periods and amplitudes in a random wave field.” Proc., Royal Society of London, London, England, A389, 241–258.
13.
Medina, J. R., Aguilar, J., and Diez, J. J. (1985). “Distortions associated with random sea simulators.” J. Wtrwy., Port, Coast., and Oc. Engrg., ASCE, 111(4), 603–628.
14.
Nath, J. H., and Yeh, R.‐C. (1987). “Some time and frequency relations in random waves.” J. Wtrwy., Port, Coast., and Oc. Engrg., ASCE, 113(6), 672–683.
15.
Sarpkaya, T., and Isaacson, M. (1981). Mechanics of wave forces on offshore structures. Van Nostrand Reinhold Co., New York, N.Y.
16.
Spanos, P.‐T. D., and Hansen, J. E. (1981). “Linear prediction theory for digital simulation of sea waves.” J. Energy Resour. Tech., 103(3), 243–249.
17.
Stansberg, C. T. (1989). “On the use, modeling and analysis of irregular water surface waves.” Proc., 8th Int. Conf. on Offshore Mech. and Arctic Engrg., American Society of Mechanical Engineers, New York, N.Y., Vol. II, 585–594.
18.
Tuah, H., and Hudspeth, R. T. (1982). “Comparisons of numerical random sea simulations.” J. Wtrwy., Port, Coast. and Oc. Div., ASCE, 108(4), 569–584.
19.
Tucker, M. J., Challenor, P. G., and Carter, D. J. T. (1984). “Numerical simulation of a random sea: A common error and its effect upon wave group statistics.” Appl. Oc. Res., 6(2), 118–122.
20.
Wang, H. T. (1985). “Temporal and spatial simulations of random ocean waves.” Proc., 4th Int. Offshore Mech. and Arctic Engrg. Symp., American Society of Mechanical Engineers, New York, N.Y., Vol. I, 72–80.
21.
Webster, W. C., and Trudell, R. W. (1981). “Statistics of local motions on a ship.” Proc., Conf. on Directional Spectra Applications, Prentice‐Hall Inc., Englewood Cliffs, N.J., 461–482.
Information & Authors
Information
Published In
Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 119 • Issue 1 • January 1993
Pages: 70 - 87
Copyright
Copyright © 1993 American Society of Civil Engineers.
History
Received: Mar 13, 1991
Published online: Jan 1, 1993
Published in print: Jan 1993
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.