ABSTRACT
Here is a calculation method that calculates drainage volume and center of buoyancy according to water surface profile. This method is also known as vertical calculation method. First, calculate the areas of the water surface profile. Then integral the water plane area along the draft direction to calculate the drainage volume and center of buoyancy. When ship’s draft is d, the positive floating state is shown in Figure 2. Pick a small layer shown in Figure 2 and calculate its volume,
d∇ = ∇ ∫A dz A⇒ = dzw wd0 Followings are static moment of this micro vol-
ume to plane YOZ and plane XOY,
d dM zA dzyoz f w xoy w=;
Calculate,
M zA dzyoz d
The buoyancy ordinate XB and the vertical coordinate ZB,
X M x A dz
A dz
Z M z A dz
A dz
=
∇ =
=
∇ =
When it’s in positive floating condition, the horizontal coordinate of the center of buoyancy YB is zero.
