SELF-EXCITED VIBRATION OF PROPELLER NOZZLES EXPERIENCED ON OCEAN- GOING TUGBOATS, 2ND REPORT

Model experiments were performed to identify causes of inordinate propeller nozzle vibration experienced on ocean-going tugboats. The galloping was imputable to flow separation over the entire outside nozzle surface, which had induced a negative slope of the lift coefficient in reference to incident angle. To prevent the occurrence of galloping, recommended measures are: (1) In design, to select and specify nozzle profile and operating parameters such as to prevent total separation of flow over outside nozzle surface; (2) As a remedial measure, to ensure a vibration mode of large structural damping; (3) In service, to reduce ship speed, so as to lower the absolute value of negative hydrodynamic damping of the nozzle.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/05148499
• Supplemental Notes:
  • Journal article
• Authors:
  • Okamura, N
  • Kumazaki, S
• Publication Date: 1985-12

Media Info

• Features: References;
• Pagination: 12 p.
• Serial:
  • Journal of the Society of Naval Architects of Japan
  • Volume: 158
  • Issue Number: No.60
  • ISSN: 0514-8499

Subject/Index Terms

• TRT Terms: Ocean going tugs; Vibration
• Uncontrolled Terms: Model tests
• Old TRIS Terms: Propeller nozzles
• Subject Areas: Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00648931
• Record Type: Publication
• Source Agency: Maritime Technical Information Facility
• Files: TRIS
• Created Date: Jul 21 1994 12:00AM