Question: A submarine is 130 m long and has a mean perimeter of 50 m. Assume its wetted surface area is hydraulically smooth and equivalent to a flat plate measuring 130m × 50m. Calculate the power required to maintain a cruising speed of 16 m/s when submerged in a polar sea at 0?C. If the engines develop the same power as before, at what speed is the submarine able to cruise in a tropical sea at 20?C?
- Take the water density to be 1000 kg/m3 and its kinematic viscosity to be 1.79 × 10-6 m2/s at 0?C and 1.01 × 10-6 m2 /s at 20?C.