Page 286 - statbility for masters and mates

274 Ship Stability for Masters and Mates
or
1 y3Edx Y 3
Fig. 30.6
Let Y be the depth of the centre of pressure below the surface, then: Moment of total thrust about OX Total Thrust Y
wg wg
3 y3Edx 2 y2EdxEY
12 y 2 Edx
The values of the two integrals can again be found using Simpson's
Rules.
Example 2
The breadth of the upper edge of a deep tank bulkhead is 12 m. The vertical heights of the bulkhead at equidistant intervals across it are 0, 3, 5, 6, 5, 3 and 0 m respectively. Find the depth of the centre of pressure below the waterline when the tank is ®lled to a head of 2 m above the top of the tank.
Area 13 CI S1 Area 13 2 68
4513 sqm