A New Theory of Wave Resistancc, based on the exact ship Surface Conditions

Abstract

The former theory of ship wave resistance does not satisfy exactly the boundary condition on ship surface. The author examines the degree of this approximation with some models by finding the actual forms which are represented by the approximate source distribution. Even in the case of ordinary fine ship, the difference between the given and actual lines gets so large unexpectedly, that the author goes to obtain the exact source distribution by solving the integral equation, and then calculates the exact wave resistance.As the first application of the new theory, the effect of breadth is studied, and it is found that the effect depends remarkably on ship speed.As the second application, the effect of water-lines forms is studied and Prof T.H. Havelock's calculations, which are refered to by D.W. Taylor in his“Speed & Power of Ships”, p.47, Fig. 59 (1933 edit.), are corrected.By the numerical comparisons in these applications, we see that the former theory does fail in almost all cases which have been investigated by the former authors, Wigley, Weinblum and etc, etc, …….