Assignment -
Learning outcomes - On successful completion of these tasks a student will:
- Be able to assess the forces acting on ship structures
- Understand basic vessel construction, design, materials and methods
- Understand trim and stability at small & large angles of heel
- Understand the effects of compartment flooding on ship, trim and stability
- Be able to analyse resistance to ship motion in relation to fuel consumption
Scenario
You have been supervising the new building of a small commercial vessel.
Part of your instructions is to assess the vessel's basic stability and hydrostatic information to produce the appropriate part of the statutory stability booklet for the vessel.
1a. Describe in detail (using appropriate diagrams/drawings) a common accepted method (experiment) you would use to obtain an accurate assessment of the vessel's initial GM.
1b. Using the following information provided below, calculate the following measurements for this vessel?
Mass Displacement.
Water plane area.
LCB (longitudinal Centre of Buoyancy).
BM.
TPC (Tonnes per centimetre Immersion)
Initial KG
Initial GM
The vessel is in salt water.
| Station |
Half area, m2 |
Waterplane half-breadths, metres |
| 0 |
0.00 |
0.0 |
| 1 |
3.04 |
1.7 |
| 2 |
4.90 |
2.6 |
| 3 |
5.02 |
3.4 |
| 4 |
4.62 |
3.4 |
| 5 |
4.21 |
3.4 |
| 6 |
3.80 |
3.4 |
| 7 |
3.38 |
3.4 |
| 8 |
2.93 |
3.4 |
| 9 |
1.79 |
2.9 |
| 10 |
0.00 |
0.0 |
Waterline length = 50m
Mean draught 1.37m
KB = 0.737m
1c. On the same vessel.
2 x weights A&B (1.8t each) are placed 2.2m each side of the LCB (v/l in equilibrium)
Weight A is moved to the position of weight B giving a pendulum movement of 75mm.
Pendulum length 3m (mounted at the LCB)
If the weight A is moved back to the original position and a new weight of 10t is loaded amidships with a CG of 3m.
What will be the shift of G and the new KG.?
1d. Explain how a KN (SZ) curve is used to determine the vessel's stability data?
Then using the vessel's calculated displacement from 1b and the KN (SZ) curve provided below for this small commercial work boat. (KS is 3.193m)
Draw the vessel's GZ curve of statical stability and state the maximum GZ value?
Attachment:- Assignment.rar