COMPARATIVE MODEL TESTS ON CAPSIZING OF SHIPS IN QUARTERING SEAS

Comparative model tests on the capsizing of container ships in quartering waves were carried out. Two hull forms were used, one with a large stability variation in waves and the other with a small stability variation. From the results the following features were found to be common to both hull forms: 1) the most dangerous encounter angle is 20~40 or 50 deg, and the dangerous range extends to 0~60 deg as the ship speed increases; 2) as the ship speed decreases, the capsizing also decreases, and there exists a critical ship speed below which capsizing never occurs; 3) the direction of capsizing is always to the leeside. Although these results are almost the same as the authors' previous model tests, the model used in previous tests proved to have an extraordinary tendency of inward heel in turning motion. It has therefore been considered necessary to reconfirm the above features by supplementary tests for more general hull forms. A previously proposed hypothetical explanation on the mechanism of capsizing in quartering waves can also explain the present results. Capsizing due to parametric rolling, which has been considered to be one of the typical modes of dynamical capsizing, was not observed for both hull forms. A new mode of dynamical capsizing accompanied with the period bifurcation phenomenon, which is regarded as a precursor of the chaos, was reconfirmed.

• Supplemental Notes:
  • STAB 94, 5th Intl Conf on Stability of Ships and Ocean Vehicles; 7-11 Nov 1994; Florida, USA. Sponsored by SNAME, USA and RINA, UK. Procs. Publ by Florida Inst Technology, USA. Vol 3, session 9 [20 p, 14 ref, 2 tab, 12 fig]
• Authors:
  • Kan, M
  • Saruta, T
  • Taguchi, H
• Publication Date: 1994

Language

• English

Subject/Index Terms

• TRT Terms: Capsizing; Stability (Mechanics)
• Uncontrolled Terms: Model tests
• Old TRIS Terms: Quartering seas
• Subject Areas: Marine Transportation; Safety and Human Factors;

Filing Info

• Accession Number: 00717280
• Record Type: Publication
• Source Agency: British Maritime Technology
• Files: TRIS
• Created Date: Mar 4 1996 12:00AM