Although contrarotating (CR) propellers have merits, their practical application to ships has been impeded by the difficulty of finding a reliable bearing and sealing arrangement for the pair of long, contrarotating propeller shafts that are entailed. A way to avoid these mechanical difficulties is noted. It involves driving the forward propeller from ahead by a shaft and engine arranged in the conventional way, and the rear propeller from behind by a level gear and strut arrangment. With this means of overcoming the difficulty explained, the advantages of a CR propeller-thruster system--i.e., of a rotatable thruster applied as a CR propeller working behind a larger conventional propeller--are detailed, and the gain in total efficiency is said to be from 5 to 10 percent.

  • Availability:
  • Supplemental Notes:
    • Journal article
  • Authors:
    • Larberg, L
    • Bjorheden, O
  • Publication Date: 1990

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Filing Info

  • Accession Number: 00661376
  • Record Type: Publication
  • Source Agency: Maritime Technical Information Facility
  • Files: TRIS
  • Created Date: Jul 21 1994 12:00AM