EFFECTS OF VORTEX EXCITATION ON THE RESPONSE OF FLEXIBLE RISERS

A new approach to vortex shedding, incorporating lift forces by a quasi-steady model, is used to evaluate the effects of vortex excitation. The modelled lift forces are used directly as a part of the external forces in the equations of motion. The effects of the vortex excitation on the flexible riser are presented by comparing the results derived in analyses with and without lift forces. Lift forces produce small lateral vibrations of the riser, and cause larger displacements under current and wave loading because of the larger displacements under current and wave loading because of the larger effective drag coefficient. Even though the vibration amplitudes are modest, the associated bending stresses are not insignificant in the context of fatigue.

• Supplemental Notes:
  • OMAE 1995, 14th Intl Conf on Offshore Mechanics & Arctic Engng; 18-22 June 1995; Copenhagen, Denmark. Sponsored by ASME et al. Procs. Publ by ASME, ISBN 0-7918-1307-X. Vol I, Pt B, p 331 [9 p, 10 fig, 3 tab, 11 fig]
• Authors:
  • SAKAMOTO, T
  • HOBBS, R E
• Publication Date: 1995

Language

• English

Subject/Index Terms

• TRT Terms: Aerodynamic lift; Vortex shedding
• Old TRIS Terms: Risers; Vortex induced vibration
• Subject Areas: Marine Transportation;

Filing Info

• Accession Number: 00718519
• Record Type: Publication
• Source Agency: British Maritime Technology
• Files: TRIS
• Created Date: Mar 27 1996 12:00AM