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What is BHP, IHP, SHP, EHP, and Torque ?

Hydrodynamics for Ocean Engineers Prof. A.H. Techet Fall 2004 Marine Propellers Today, conventional marine propellers remain the standard propulsion mechanism for surface ships and underwater vehicles. Modifications of basic propeller geometries into water jet propulsors and alternate style thrusters on underwater vehicles, has not significantly changed how we determine and analyze propeller performance. We still need propellers to generate adequate thrust to propel a vessel at some design speed with some care taken in ensuring some “reasonable” propulsive efficiency. Considerations are made to match the engine’s power and shaft speed, as well as the size of the vessel and the ship’s operating speed, with an appropriately designed propeller. Given that the above conditions are interdependent (ship speed depends on ship size, power required depends on desired speed, etc.) we must at least know a priori our desired operating speed for a given vessel. Following this we should understand