World Library  
Flag as Inappropriate
Email this Article


Article Id: WHEBN0000870613
Reproduction Date:

Title: Propulsor  
Author: World Heritage Encyclopedia
Language: English
Subject: Acoustic signature, Magnetohydrodynamic drive, L-drive, Akula-class submarine, Garfield Thomas Water Tunnel
Collection: Marine Propulsion
Publisher: World Heritage Encyclopedia


Mark-50 torpedo propulsor

A propulsor is a mechanical device that gives propulsion. The word is commonly used in the marine vernacular, and implies a mechanical assembly that is more complicated than a propeller. The Kort nozzle and pump-jet are examples.

An example propulsor is shown in the accompanying picture. It has a shroud which cuts down on blade-tip cavitation and radiated noise. It also has a rotor element and a stator. The stator concentrates the thrust in axial direction and reduces energy wasted in the tangential flow (therefore eliminating torque on the hull). The number of blades in the rotor & stator will typically be two different prime numbers to avoid standing waves. The blades in the rotor or the stator may be angled to further reduce noise. The physical design and layout is very much similar to a single stage axial-flow compressor.


  • Other propulsors 1
    • Voith Schneider 1.1
    • Azimuth thruster 1.2
    • Magnetohydrodynamic drive 1.3
  • See also 2
  • External links 3

Other propulsors

Voith Schneider

Voith‐Schneider propeller

The Voith Schneider Propeller (VSP), also known as a cycloidal drive (CD) is a specialized marine propulsion system (MPS). It is highly maneuverable, being able to change the direction of its thrust almost instantaneously. It is widely used on tugs and ferries.

From a circular plate, rotating around a vertical axis, a circular array of vertical blades (in the shape of hydrofoils) protrude out of the bottom of the ship. Each blade can rotate itself around a vertical axis. The internal gear changes the angle of attack of the blades in sync with the rotation of the plate, so that each blade can provide thrust in any direction, very similar to the collective pitch control and cyclic in a helicopter.

Azimuth thruster

Siemens Schottel azimuth thrusters

An azimuth thruster is a configuration of ship propellers placed in pods that can be rotated on the horizontal plane, making a rudder unnecessary. These give ships better maneuverability than a fixed propeller and rudder system.

Magnetohydrodynamic drive

A magnetohydrodynamic drive or MHD propulsor is a method for propelling seagoing vessels using only electric and magnetic fields with no moving parts, using magnetohydrodynamics. The working principle involves electrification of the propellant (gas or water) which can then be directed by a magnetic field, pushing the vehicle in the opposite direction. Although some working prototypes exist, MHD drives remain impractical and exist mostly in the world of science fiction. Tom Clancy's fictional submarine Red October in his novel The Hunt for Red October employed a magnetohydrodynamic drive for virtually silent propulsion.

See also

External links

  • Rolls-Royce Marine
  • Schottel marine propulsion
  • Pleuger Propulsion
  • Voith Schneider propulsors
  • Kort nozzles
  • Tug boat FAQ
  • UltraJet web site
  • ZF Marine
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.