Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-11T00:30:32.814Z Has data issue: false hasContentIssue false

Kelvin Ship Wake in the Wind Waves Field and on the Finite Sea Depth

Published online by Cambridge University Press:  31 March 2011

M.-C. Fang
Affiliation:
Research Center of Ocean Environment and Technology, National Cheng Kung University, Tainan, Taiwan 70101, R.O.C.
R.-Y. Yang*
Affiliation:
Research Center of Ocean Environment and Technology, National Cheng Kung University, Tainan, Taiwan 70101, R.O.C.
I. V. Shugan
Affiliation:
Research Center of Ocean Environment and Technology, National Cheng Kung University, Tainan, Taiwan 70101, R.O.C.
*
** Associate Director, corresponding author
Get access

Abstract

A kinematics model of the ship wake in the presence of surface waves, generated by wind is presented. It was found that the stationary wave structure behind the ship covered a wedge region with the 16.9° half an angle at the top of the wake and only divergent waves are present in a ship wake for co propagating wind waves. Wind waves field directed at some nonzero angle to the ship motion can cause essential asymmetry of the wake and compressing of its windward half. The extension of Whitham-Lighthill kinematics theory of ship wake for the intermediate sea depth is also presented. The ship wake structure essentially depends from the Froude (Fr) number based on the value of the sea depth and ship velocity. For Froude number less than unit both longitudinal and cross waves are presented in the wake region and Kelvin wake angle increased with Fr. For Fr > 1 wake angle decreased with Froude number and finally only divergent waves are presented in the very narrow ship wake.

Type
Articles
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Kelvin W., Thomson), Deep sea ship-waves, Mathematical and Physical Papers, V.4, Cambridge, pp. 303306 (1910).Google Scholar
2.Lighthill, M. J. and Whitham, G. B., “On Kinematic Waves: I. Flood Movement in Long Rivers; II. Theory of Traffic Flow on Long Crowded Roads,” Proceedings of the Royal Society A, 229, pp. 281345 (1955).Google Scholar
3.Reed, A. and Milgram, J., “Ship Wakes and Their Radar Images,” Annual Review of Fluid Mechanics, 34, pp. 469502 (2002).CrossRefGoogle Scholar
4.Shemdin, O. H., “Synthetic Aperture Radar Imaging of Ship Wakes in the Gulf of Alaska,” Journal of Geophysical Research, 95, pp. 1631916338 (1990).CrossRefGoogle Scholar
5.Hennings, I., Romeiser, R., Alpers, W. and Viola, A., Radar Imaging of Kelvin Arms of Ship Wakes International Journal for Remote Sensing, 20, pp. 25192543 (1999).Google Scholar
6.Case, K., Dashen, R., Munk, W., Vesecky, J. and Watson, K.SEASAT report. Jason Rep. JSR 84–203, Mitre Corp., McLean, Virginia, p. 221 (1985).Google Scholar
7.Melsheimer, C., Lim, H. and Shen, C., “Observation and Analysis of Ship Wakes in ERS-SAR and SPOT Images,” Proceedings of the 20th Asian Conference on Remote Sensing, Hong Kong, China, pp. 554559 (1999).Google Scholar
8.Alpers, W., Romeiser, R. and Hennings, I., “On the Radar Imaging Mechanism of Kelvin Arms of Ship Wakes,” Proceedings IGARSS'98, IEEE, Piscataway, NJ, pp. 19321934 (1998).Google Scholar
9.Tunaley, J. K. E., Buller, Eric H., Wu, K. H. and Rey, Maria T., “The Simulation of the SAR Images of a Ship Wake,” Geoscience and Remote Sensing IEEE Transactions, 29, pp. 149155 (1991).CrossRefGoogle Scholar
10.Tunaley, J., “The Unsteady Wake from a Body Moving Near an Internal Layer,” Proceedings of the 5th Canadian Conference on Marine Hydromechanics and Structures, St. Johns, Newfoundland, pp. 513 (1999).Google Scholar
11.Eldhuset, K., “An Automatic Ship and Ship Wake Detection System for Spaceborne Sarimages in Coastal Regions,” Geoscience and Remote Sensing IEEE Transactions, 34, pp. 10101019 (1996).CrossRefGoogle Scholar
12.Kuo, J. M. and Chen, K. S., “The Application of Wavelets Correlator for Ship Wake Detection in SAR Images,” IEEE Transaction Geoscience and Remote Sensing (SCI), 41, pp. 15061511 (2003).Google Scholar
13.Akylas, T., “Unsteady and Nonlinear Effects Near the Cusp Lines of the Kelvin Ship- Wave Pattern,” Journal of Fluid Mechanics, 175, pp. 333342 (1987).CrossRefGoogle Scholar
14.Phillips, O. M., The Dynamics of the Upper Ocean, 2nd Ed., Cambridge Univ. Press, Cambridge (1977).Google Scholar
15.Whitham, G. B., Linear and Nonlinear Waves, Wiley, New York (1999).CrossRefGoogle Scholar