elopments in Theory of Bulbous Ships 



WAVES 



LOCAL DISTURBANCE 



REGULAR WAVES 



HIGHER ORDER 

 WAVES 



SUPERPOSITION OF 

 ELEMENTARY WAVES 



COSINE WAVES 



Fig. 1 - Diagram for the characteristics of ship waves 



surface. The intersection of the ship's center plane and the mean free surface 

 is taken as the x axis, with the z axis perpendicular to the free surface, posi- 

 tive upward. The flow at x = - oo is considered to be uniform with the velocity v 

 parallel to the x axis in the positive x direction (see Fig. 2). 



SHIPS OF MINIMUM WAVE RESISTANCE AND 

 BULBOUS SHIPS 



Since Michell's wave resistance formula (1898) was found, problems of 

 finding the Michell's linearized ship which has the minimum wave resistance 

 have been attacked by many hydrodynamists in various forms and ways. 

 Sretenskii (1935), Pavlenko (1937), Karp, Votik and Lurye (1958) and Maruo and 

 Bessho (1962) treated symmetric infinite vertical struts. Weinblum (1930, 1957), 

 Krein (1955) and Martin (1961) dealt with three-dimensional symmetric ship 



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