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Q15. A ship 160 m in length floats in sea water of density 1025 kg/m³. At the load draught, the

Immersed sectional areas of the main body of the ship are as given in Table Q1A

Calculate EACH of the following:

(a) The displacement;

(b) The longitudinal position of the center of buoyancy from midships.

Q2. A ship has a lightship displacement of 9500 tonne and the height of the centre of gravity above the keel (KG) is 8.54 m.  Loading now takes place as detailed in Table Q2.

Table Q2

In this loaded condition, the height of the transverse metacentre above the keel (KM) is 10.38m.

(a) Draw a curve of statical stability for the loaded vessel, using the cross curves of stability provided in Worksheet Q2.  (12)

(b) Using the curve derived in Q 2 (a), determine the dynamical stability of the vessel up to an angle of  40^o.  (4)

Q3) A ship of 125 m length has the following particulars when floating in sea water of density 1025 kg/m³ .

Displacement  = 11923 tonne

Draught aft  = 7.244 m

Draught forward  = 6.844 m

Longitundinal metacentric height (GML)  = 130 m

Longitudinal centre of floating (LCF)  = 2.5 m aft of midships

Tonne per centimetre immersion (TPC)   = 18.5

TWO tanks, EACH contanining a substantial quantity of water ballast, are situated with their centres of gravity 50 m aft of midships and 25 m forward of midships respectively.

The vessel is required to enter dock with a draught aft of 7.0 m and a trim of 0.6 m by the stern.

Calculate the mass of ballast to be removed from each tank. (16)

Q5. A rectangular oil barge of light displacement 300 tonne is 60 m tong and 10 m wide. The barge is divided by four transverse bulkheads into five Compartments of equal length.

When compartments 2 and 4 contain equal quantities of oil and the other compartments are empty, the barge floats at a draught of 3 m in fresh water of density 1000 kg/m³.

(a) Plot EACH of the following curves on a base of barge length:

(i) curve of toads; (4)

(ii) curve of shearing forces; (4)

(iii) curve of bending moments.  (5)

(b) State the magnitude and position of the maximum bending moment. (3)

Q15. The following results in Table Q5 were obtained from resistance tests on a ship model 6 m in length having a wetted surface area of 7 m² in fresh water of 1000 kg/m³ at a Temperature of 12°C.

Ship correlation factor 1.18

Temperature correction ±0.43% per °C

Calculate the effective power of a similar ship 140 in long travelling at a speed of 18 knots in sea water of density 1025 kg/rn³ at a temperature of l5 °C

Note: The frictional coefficient for the model in water of density 1000 kg/m³ at 15°C is 1.655

The fractional coefficient for the ship in water of density 1025 kg/rn³ at 15 °C is 1.415

Speed in m/c with index (n) for ship and model 1.825

Q8. A ship 145 m long and 23 m beam displaces 19690 tonne when floating at a draught of 8 m in sea water of density 1025 kg/m³.

The following data are given for the service speed of 16 knots:

Effective power (naked) = 3450 kW

Appendage and weather allowance = 20%

Quasi-propulsive coefficient = 0.71

Thrust deduction fraction = 0.21

Transmission losses = 3%

Specific fuel consumption = 0.205 kg/kW hr

The Taylor wake fraction is obtained from: wt = 0.5 Cb - 0.05

(a) Calculate EACH of the following at the service speed:

(i) The delivered power;

(ii) The thrust power;

(iii) The fuel consumption per day.

(b) Calculate the maximum speed at which the ship must travel to complete a voyage of 3000 nautical miles, with only 200 tonne of fuel on board.

Q4) With reference to the inclining experiment:

(a) state the purpose of the experiment and when the experiment should be performed during the life of a ship; (2)

(b) explain the procedure immediately prior to the experiment; (4)

(c) describe the procedure for the experiment; (4)

(d) list SIX precautions to ensure acceptable accuracy of results. (6)