scholarly journals Ship waves on a viscous fluid of finite depth

1997 ◽  
Vol 9 (4) ◽  
pp. 940-944 ◽  
Author(s):  
Andy T. Chan ◽  
Allen T. Chwang
2014 ◽  
Vol 742 ◽  
Author(s):  
Simen Å. Ellingsen

AbstractLord Kelvin’s result that waves behind a ship lie within a half-angle $\phi _{\mathit{K}}\approx 19^{\circ }28'$ is perhaps the most famous and striking result in the field of surface waves. We solve the linear ship wave problem in the presence of a shear current of constant vorticity $S$, and show that the Kelvin angles (one each side of wake) as well as other aspects of the wake depend closely on the ‘shear Froude number’ $\mathit{Fr}_{\mathit{s}}=VS/g$ (based on length $g/S^2$ and the ship’s speed $V$), and on the angle between current and the ship’s line of motion. In all directions except exactly along the shear flow there exists a critical value of $\mathit{Fr}_{\mathit{s}}$ beyond which no transverse waves are produced, and where the full wake angle reaches $180^\circ $. Such critical behaviour is previously known from waves at finite depth. For side-on shear, one Kelvin angle can exceed $90^\circ $. On the other hand, the angle of maximum wave amplitude scales as $\mathit{Fr}^{-1}$ ($\mathit{Fr}$ based on size of ship) when $\mathit{Fr}\gg 1$, a scaling virtually unaffected by the shear flow.


The theory of ship waves, when the sea is considered to be of infinite depth, has been the subject of many researches. When the sea is of finite depth the integrals involved are more complicated, but in this case also the theory has been worked out in considerable detail. The main object of the present communication is to add to the number of cases which have been solved, or, to be more precise, which have been exactly formulated, a certain series in which the depth is variable. Of subsidiary interest, but coming under the title of the paper, are some considerations relating to the wave disturbance when the depth is finite. These are dealt with briefly in section 5.


2005 ◽  
Vol 54 (10) ◽  
pp. 4496
Author(s):  
Wu Yun-Gang ◽  
Tao Ming-De

1972 ◽  
Vol 3 (4) ◽  
pp. 46-49
Author(s):  
L. V. Cherkesov
Keyword(s):  

2002 ◽  
Vol 23 (10) ◽  
pp. 1221-1228 ◽  
Author(s):  
Liu Min-jia ◽  
Tao Ming-de

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