Page 284 - statbility for masters and mates

272 Ship Stability for Masters and Mates
Find the depth of the centre of pressure below the waterplane when the hold is ¯ooded to a depth of 2 metres above the top of the bulkhead.
Ord. SM
15.4 1 15.4 4 15.4 2 15.3 4 15.0 1
Area func. Lever
15.4 0 61.6 1 30.8 2 61.2 3 15.0 4
366:8 S2 Area 13 h S1 3 184:0
184sqm
Moment func. Lever
0 0 61.6 1 61.6 2
183.6 3 60.0 4
Inertia func.
0 61.6
123.2 550.8 240.0
975:6 S3
184:0 S1
Referring to Figure 30.5:
CG
CD z IOZ
ICG IWL
IWL y
S2 h S1
366:8 3 184
5:98 m
2:00 m
7:98 m
13 h3 S3 13 33 975:6 8780m4
IOZ A (CG)2, i.e. parallel axis theorem ICG A z2
IOZ A(CG2 z2)
8780 184 5:982 7:982
13928m4
IWL A z
13928 184 7:98
y 9 : 5 m .
Ans. The Centre of
Pressure is 9.5 m below the waterline.