R & D OF A DISPLACEMENT-TYPE HIGH SPEED SHIP; PART 3, SEAKEEPING QUALITIES IN HIGH SPEED RANGE

For the estimation of seakeeping qualities in the normal speed range, theoretical prediction methods, such as the strip method are commonly used. However such methods have not been verified in the high speed range up to 50 knots, and their applicability remains uncertain. Consequently, seakeeping model tests were carried out in regular and irregular head waves, frequency response functions in regular waves and short-term responses in irregular waves were obtained for ship motions, acceleration, relative motion, and vertical wave loads. Comparison between theoretical calculations and experimental results revealed that the strip method can generally estimate ship motions and wave loads even at Fn=0.6. However, for the accurate prediction of short-term responses in irregular waves, experimental values of frequency response functions should be used. From the study of seaworthiness in irregular head waves of various sea states at various ship speeds, it is proved that the displacement- type high speed ship generally has good seakeeping qualities for ship motions and vertical wave loads. However, vertical accelerations and relative bow motions are estimated to be significant in the high speed range in long-mean-period irregular waves.

• Supplemental Notes:
  • Fast '93, 2nd Intl Conf on Fast Sea Transportation; 13-16 Dec 1993; Yokohama, Japan. Sponsored by Min Transport, Japan & Sasakawa Foundation. Procs. Pubs by Soc Naval Architects of Japan, 1993, ISBN 4-930966-00-0. Vol 1, p 341 [10 p, 5 ref, 1 tab, 6 fig]
• Authors:
  • Takarada, N
  • Takezawa, S
• Publication Date: 1993

Language

• English

Subject/Index Terms

• TRT Terms: Seakeeping; Strip method
• Uncontrolled Terms: High speed vessels; Model tests
• Old TRIS Terms: Displacement hulls
• Subject Areas: Marine Transportation;

Filing Info

• Accession Number: 00709570
• Record Type: Publication
• Source Agency: British Maritime Technology
• Files: TRIS
• Created Date: Aug 14 1995 12:00AM