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LuckyWell [14K]
3 years ago
9

Transverse thrusters are used to make large ships fully maneuverable at low speeds without tugboat assistance. A transverse thru

ster consists of a propeller mounted in a duct; the unit is then mounted below the waterline in the bow or stern of the ship. The duct runs completely across the ship. Calculate the thrust developed by a 1900 kW unit supplied to the propeller if the duct is 2.6 m in diameter and the ship is stationary.
Physics
1 answer:
suter [353]3 years ago
8 0

Answer:

Thrust developed = 212.3373 kN

Explanation:

Assuming the ship is stationary

<u>Determine the Thrust developed</u>

power supplied to the propeller ( Punit ) = 1900 KW

Duct distance ( diameter ; D  ) = 2.6 m

first step : <em>calculate the area of the duct </em>

A = π/4 * D^2

   =  π/4 * ( 2.6)^2  = 5.3092 m^2

<em>next : calculate the velocity of propeller</em>

Punit = (A*v*β ) / 2  * V^2     ( assuming β = 999 kg/m^3 ) also given V1 = 0

∴V^3 = Punit * 2 / A*β

         = ( 1900 * 10^3 * 2 ) / ( 5.3092 * 999 )

hence V2 = 8.9480 m/s

<em>Finally determine the thrust developed </em>

F = Punit / V2

  = (1900 * 10^3) / ( 8.9480)

  = 212.3373 kN

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