Adjustable pitch screw, variable pitch screw, variable pitch screw ( VRS , VISH ) - a screw propeller, the angle of attack of the blades of which is not specified during production, but can be changed directly during operation.
SRS consists of a hub, blades and a mechanism that rotates and fixes the blades.
This type of screw is more complicated, heavier and more expensive than fixed pitch screws, but it is widely used in shipbuilding and aviation. The variable pitch of the screw allows maintaining the propulsion efficiency close to optimal regardless of the speed of the carrier in the stream. It also allows you to realize the reverse of the mover without changing the direction of its rotation - due to the rotation of the blades in the desired direction (so that the stop of the mover was directed against the movement of the object).
Using an adjustable pitch propeller on a vessel in ice conditions is not effective due to the high probability of such a screw breaking on ice.
See also
- Mover
- Propeller screw
- Air propeller
Links
- adjustable pitch screw
- Kuzmin G.I. Propellers. M .: Oborongiz, 1937., ch. 4. Adjustable pitch screws. 1 (inaccessible link)