Jet ring propeller
The jet ring propeller is a drive system of some modern submarine and torpedo types in which a rotor , similar to a compressor wheel of a turbine drive , rotates against a stator of a similar shape. Both are located within a round collar around the stern of the boat, through which they pump water with their opposing blades in order to generate sufficient propulsion even at a comparatively low number of revolutions. As a result, the vehicle is considerably quieter and more difficult to locate at the same speed. The disadvantage compared to a conventional propeller is the extra weight and the increased water resistance .
The conventional drive for military submarines, on the other hand, consists of one or two large propellers, about seven-bladed models with a supine position.
In a variant of the drive, two propellers rotate against each other within a collar. This design is suitable for higher speeds and is about the 48 mark - Torpedo used.
The British Trafalgar class was the first class to receive such a drive system in the early 1980s. France then implemented it in the Triomphant class , the United States Navy in the Seawolf class and later in the Virginia class . The Russian Navy uses the jet ring propeller on the diesel-electric submarine Alrosa of the Kilo class (variant 877W) and in the boats of the Borei class with nuclear propulsion . The British Astute class planned from 2009 and the French Suffren class planned from 2017 will also use a nozzle ring propeller. In addition, it is still installed in the Spearfish and Mark 48 torpedo .
Terminology, definition of terms
The direct-acting nozzle ring propeller should not be confused with an indirectly-acting water jet propulsion system (also known as a pump jet, pump jet propulsion system , etc.), which takes water from the environment in order to accelerate it in a pipe system and then use it to drive it by means of an outlet nozzle . Although the two systems differ significantly, the nozzle ring propeller is often referred to in the specialist literature as a water jet propulsion system or is at least assigned to it.
The nozzle ring propeller should also not be confused with the propeller pods used in shipbuilding, some of which are also sheathed propellers.
confidentiality
The nozzle ring propeller is only installed in military underwater vehicles. Because of this, and because it is only installed on relatively few vehicles, the level of secrecy was comparatively high.
Individual evidence
- ^ The world of ships , p. 521, Bassermann, 2007, ISBN 978-3-8094-2186-3
- ^ Robert Hutchinson: Combat under water, submarines from 1776 to today. Motorbuchverlag, Stuttgart 2006, ISBN 978-3-613-02585-1 , in particular pp. 152-153.
- ↑ Anthony Preston: The History of the Submarines. Karl Miller Verlag, ISBN 3-86070-697-7 .
- ↑ a b c FAS: MK-48 Torpedo Federation of American Scientists , fas.org, accessed October 31, 2019.