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Q8. A ship 150 m in length, 24 m breadth, displaces 25000 tonne when floating at a draught of 9 m in sea water of density 1025 kg/m³. The ship’s propeller has a diameter of 5.8 m, a pitch ratio of 0.9 and a blade area ratio of 0.45. With the propeller operating at 2 rev/sec, the following results were recorded:

Apparent slip ratio = 0.06

Thrust power = 3800 kW

Propeller efficiency = 64%

The Taylor wake fraction is given by: WT = 0.5CB - 0.05

Calculate EACH of the following for the above condition:

(a) The ship’s speed

(b) The real slip ratio

(c) The thrust per unit area of blade surface

(d) The torque delivered to the propeller.