Anna University Naval Architecture Model Test Paper
MARINE ENGINEERING
Time : 3 Hours Maximum Marks 100
Answer All Questions PART – A (10 x 2 = 20 marks)
1.Draw neat sketches of the following ship’s members:
(a) Rise of Keel (b) Bulbous Bow.
2.Explain the meaning of the following terms:
(a) BM_{T} (b) MCT 1 cm
3.The Water plane area of a ship is 1730 sq.m. Calculate TPC and the increase in draught if a mass of 270 tonne is added to the ship.
4.Define Prismatic Coefficient and Midship section area Coefficient.
5.Explain dynamical stability?
6.What is free Surface Effect? How it affects the metacentric height of the ship?
7.Define a) Trim b) LCF
8.A ship of 10,000 tonne displacement has a Water plane area of 1,300 sq.m. The ship loads in water of 1.010 t/cu.m and moves into water of 1.026 t/cu.m. Find the change in Mean draught.
9.On what factors the frictional resistance of a ship depends?
10.Explain what is ‘Ship Correlation Factor’?
PART – B (5 x 16 = 80 marks)
Question No. 11 is compulsory, Question Nos. 12 to 15, Answer (a) or (b) from each unit.
UNIT – I
11.Draw a typical midship section of a general cargo ship and name all the structural members. (16 marks)
UNIT – II
12.a)i)A ship 13.5 m long, 18 m beam and 7.6 m draught has a displacement of 14,000 tonne. The area of the load water plane is 1,925 sq.m. and the area of the immersed midship section is 130 sq.m. Calculate (1) Cw (2) Cm (3) Cb (4) Cp.
(12 marks)
ii)A ship of 5,000 tonne displacement, 95 m. long floats at a draught of 5.5 m. Calculate the wetted surface area of the ship using Denny’s formula. (4 marks
OR
12.b)A double bottom tank 21 m. long has a water tight center girder. The widths of the tank top measured from the center line to the ship side are 10.0, 9.5, 9.0, 8.0, 6.5, 4.0, and 1.0 m respectively. Calculate the second moment of area of the tank surface about a longitudinal axis through its centroid for one side of the ship only. (16 marks)
UNIT – III
13.a)Sketch the transverse section of a ship, showing the positions of Centre of Gravity, Centre of Buoyancy, and Initial Metacentre, when the ship is in (1) stable (2) unstable and (3) neutral equilibrium.
OR
13.b)i) A small vessel has the following particulars before modifications are carried out. Displacement150 tonne, GM: 0.45 m, KG: 1.98 m, KB: 0.9 m., TPC: 2.0, and draught: 1.65 m. After modification, 20 tonne has been added and KG: 3.6 m, Calculate the new GM, assuming constant water plane area over the change in draught. (8 marks)
ii) A ship of 12,000 tonnes displacement has a metacentric height of 0.6 m. and a Centre of Buoyancy of 4.5 m above the keel. The second moment of area of water plane about the centre line is 42.5 x 10^{3}m^{4}. Calculate the height of CG above keel.
(8 marks)
UNIT – IV
14a) A ship 80m, long has a light displacement of 1,050 tonne and LCG 4.64 m, aft of midships. The following items are then added:
Cargo 2,150 tonne, LCG 4.71 m, Fwd of midships.
Fuel 80 tonne, LCG 32.55 m, Aft of midships.
Water 15 tonne, LCG 32.9 m, Aft of midships.
Stores 5 tonne, LCG 33.6m, Fwd of midships.
Following hydrostatic particulars are available :
Draught Mtr.

Displacement Tonne 
MCT 1 cm Tonne m. 
LCB from midship (m) 
LCF from midship (m) 
5.00  3,533  43.10  1.00 F  1.27A 
4.50  3,172  41.26  1.24 F  0.84 A 
Calculate the final draughts of the loaded vessel. (16 marks)
OR
14.b) The draught of a ship 90 m. long are 5.80 m forward and 6.40 m. aft. MCT 1 cm is 50 tonne m., TPC: 11, LCF: 2 m. aft. of midships. Determine the point at which a mass of 180 tonnes should be placed so that the aft. draught remains unaltered and calculate the final draught forward. (16 marks)
15.a) A 6 m, model of a ship has a wetted surface area of 8 sq. m. When towed at speed of 3 knots in fresh water, the total resistance is found to be 38 N. If the ship is 130 m. long, calculate the effective power at the corresponding speed. Take n = 1.825, SCF : 1.15. Calculate ‘f’ from the formula. (16 marks)
OR
15.b)A ship’s speed is increased by 20 % above normal for 8 hours, reduced by 10 % below normal for 10 hours and for the remaining 6 hours of the day, the speed is maintained normal. Calculate the percentage variation in fuel consumption in that day form normal. (16 marks)
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