The functioning is more easily understood if you consider only those VSP blade
positions within which thrust is generated.
Blade movements on opposite sides of the propeller
On a Voith-Schneider Propeller the blades project below the ships hull and rotate about a vertical axis, having an oscillatory motion about its own axis superimposed on this uniform motion. Compared to a classic screw , the functioning of the Voith-Schneider propeller is more difficult to explain.
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The functioning is more easily understood if you consider only those VSP blade
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The blade's oscillating movement - a non-stationary process in hydrodynamic theory - determines the magnitude of thrust through variation of the amplitude, the phase correlation determining the thrust direction between 0 and 360 degrees. Therefore there is no preferred direction. A fish's fin action not only produces a force in the direction of motion but simultaneosly forces normal to that direction during a fish's steering force. In nature many animals use such movement and in this way optimally adapted to their living environment.
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"Skulling" is known by every sailor -a movement where by oscillating the |  |
Actual path of one blade.
By superimposing the rotary movement of the propeller on a straight line perpendicular to the rotational axis (to represent the movement of the vessel), the blade of the Voith-Schneider Propeller follows a cycloid.
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1 Lower spherical bush 2 Link 3 Bearing pin 4 Crank 5 Connecting rod 6 Actuating lever |
neutral position, | thrusting position, |
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The hydrodynamic principle of the blade action are produced mechanically by the "heart" of VSP: the kinematics.
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The figure shows a vertical bodycut of a type "G" propeller whith crank type kinematics.
