SELF-EXCITED VIBRATION OF PROPELLER NOZZLES EXPERIENCED ON

Violent vibrations were reported on two large ocean-going tugboats built by IHI, which were equipped with controllable pitch propellers and fixed nozzles. It was postulated that the self-excited vibration was caused by locked-in vibration induced by Karman's vortex streets, occurring downstream of the nozzle trailing edges, and because of the occurrence of negative damping. The vibrations have been completely suppressed by attaching fins to the nozzle to modify the resonance velocity, and hence the exciting frequency, and by placing strutting between the two nozzles to alter the negative damping to positive values.

• Supplemental Notes:
  • Ocean-Going Tugboats -- 1st Report -- <in English>. Soc. Nav. Arch. Japan, 156 <1984>, p. 388 <Dec.> (9 pp., 3 refs., 3 tab., 19 diag.)
• Authors:
  • Ogawa, Y
  • Kumazaki, S
• Publication Date: 1984

Language

• English

Subject/Index Terms

• Subject Areas: Marine Transportation;

Filing Info

• Accession Number: 00688093
• Record Type: Publication
• Source Agency: British Maritime Technology
• Files: TRIS
• Created Date: Aug 14 1995 12:00AM