A box-shaped vessel 100m long, 15m beam floating in salt water, at a mean draft of 5m, has an amidships compartment 10m long which is loaded with a general cargo. Find the new mean draft if this compartment is bilged, assuming the permeability to be 25 percent.

A box-shaped vessel 100m long, 15m beam floating in salt water, at a mean draft of 5m, has an amidships compartment 10m long which is loaded with a general cargo. Find the new mean draft if this compartment is bilged, assuming the permeability to be 25 percent.

Reference: Ship Stability for Masters & Mates (6^th edition), Exercise – 22.1

 

Solution:

Increase in draft = (L*B*d*μ)/(L-l) *B

                            = (10*15*5*0.25)/ (100-10) *15

                            = 0.1388 m

New draft = 5 + 0.138 = 5.138 m