When a body is moving in a undisturbed water the surface create a varying pressure field which manifests itself as waves because the pressure at the surface must be constant and equal to atmospheric pressure.
From observation when the body moves at a steady speed, the wave pattern seems to remain the same and move with the body. With a ship the energy for creating and maintaining this wave system must be provided by the ship's propulsive system. Put another way, the waves cause a drag force on the ship which must be opposed by the propulsor if the ship is not to slow down. This drag force is the wave-making resistance.
Several attempt have been made to reduce the wave making resistance of the ship, with varying degrees of success. One method which has proved to be successful is the use of bulbous bow. The wave produced by the bulb interferes by the wave produced by the stern, resulting in a reduced height of bow wave and consequent reduction in the energy required to produce the wave.
From observation when the body moves at a steady speed, the wave pattern seems to remain the same and move with the body. With a ship the energy for creating and maintaining this wave system must be provided by the ship's propulsive system. Put another way, the waves cause a drag force on the ship which must be opposed by the propulsor if the ship is not to slow down. This drag force is the wave-making resistance.
Several attempt have been made to reduce the wave making resistance of the ship, with varying degrees of success. One method which has proved to be successful is the use of bulbous bow. The wave produced by the bulb interferes by the wave produced by the stern, resulting in a reduced height of bow wave and consequent reduction in the energy required to produce the wave.
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