20 WAVE RESISTANCE THEORY AND APPLICATION 
vious that this method would not be worth while 
for low speeds, as the number of elements would 
be too large and other methods of calculation, 
such as that used by Weinblum, would be less 
laborious. However, one possible extension is of 
some interest; we may subdivide the ship into 
compartments also by longitudinal vertical planes, 
so that the sources are not just located in one 
plane but are distributed in space. This repre- 
sents an attempt to extend the theory to models 
of fuller form than can be represented adequately 
by a plane distribution; although the method is 
rather crude, it might give some better idea of the 
15.0 
effect of finite beam. I reproduce some diagrams 
to show the sort of results which have been ob- 
tained by these methods. 
Fig. 8 shows calculated and observed wave pro- 
file for a certain model. The calculations were 
made both by the wedge method and by the 
source method, and there is not much difference 
in the first approximation; it should be added 
that Guilloton has considered various second 
order corrections by his method, and his cor- 
rected curve in this diagram shows extremely good 
agreement with the observed profile. 
12.5 | 
Longeur:4.8 
5.0 
Profils de Vague calcules et mesurés 
Model 755 Equation n=(1-Z?) cos ( E/2) 
6m. Largeur: 0.610m. Profondeur 0310m 
Vitesse: c=3.5| m/s. Numbre de Froude: C/VgL=0.505 
Profil mesuré 
75 ———— Calcul de Guilloton 
i —-—-— Calcu] de Guilloton avec correction 
Calcul par la methode des Sources 
N 
o 
Niveau deleau @ lJinfini 
[o) 
| 
N 
oO 
Hauteur de la Vague en Cm 
5.0 
US 
-10.0 
0.2 
0) 
Valeurs de & 
Fic. 8 
570 
