In this article published in Riviera Maritime Media’s Marine Propulsion magazine, Patrik Wheater reports on the developments taking place to reduce underwater radiated propeller noise.
As the International Maritime Organization’s Sub-Committee on Ship Design and Construction continues its work to review 2014 guidelines for underwater radiated noise (URN) abatement, existing propeller and shaft technology can be easily retrofitted for a more peaceful marine environment.
The review aims to make new recommendations based on the latest developments in ship design and technology and to address any barriers that could prevent the wider take up of noise reduction measures.
Initial findings from research carried out by Thordon Bearings indicates a seawater-lubricated propeller shaft could have an important role to play in reducing propeller noise given it is significantly quieter than one lubricated by oil.
While comparative studies have yet to be completed, the Canadian polymer bearings specialist says the low URN of a ship operating seawater-lubricated propeller shaft bearings is, more than any other aspect, the primary reason why the arrangement is favoured by naval forces and the fisheries sector.