SYSTEMATIC STUDIES OF CONTRA-ROTATING PROPELLERS FOR MERCHANT SHIPS

This paper describes work carried out at the Swedish State Shipbuilding Experimental Tank in which a family of contra-rotating propeller models, the SSPA K118 CR-series, has been developed in order to examine the hydrodynamic properties and possible improvements in relation to other propeller arrangements. The results of open water and cavitation tests in homogeneous flow and behind conditions carried out in the SSPA cavitation tunnel No. 1, are discussed. The cavitation tests in homogeneous flow covers determination of incipient cavitation limits and studies of cavitation patterns at different loadings. Cavitation tests with propeller models in behind conditions were executed with two propeller sets, one suitable for a 150,000 tdw tanker and the other for a 12,000 tdw container ship. Self-propulsion tests were also carried out for these two projects. All the results have been compared with those available for conventional single propeller arrangement, and the paper shows how, with the aid of faired values of geometric and propulsive properties, power predictions and geometric data of an arbitary propeller for any loading within the range can be determined.

• Supplemental Notes:
  • 45 Conference Papers presented at IMAS 73, London, 4-8 June 1973, organized by the Institute of Marine Engineers. This paper is available only in a set of 6 papers in Subject Group 9: "Stern Gear, Shafting and Propellers" at $10.00.
• Corporate Authors:

  Institute of Marine Engineers

  Memorial Building, 76 Mark Lane
  London EC3R 7JN,   England 
• Authors:
  • BJARNE, E
• Publication Date: 1973

Subject/Index Terms

• TRT Terms: Cavitation (Mechanics); Cavitation erosion; Contrarotating propellers; Energy consumption; Mechanical loads; Open water tests
• Old TRIS Terms: Power prediction; Propeller loading
• Subject Areas: Energy; Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00048490
• Record Type: Publication
• Source Agency: Institute of Marine Engineers
• Files: TRIS
• Created Date: Nov 14 1973 12:00AM