SEAKEEPING TESTS OF A 250,000 DWT TANKER MODEL IN VARIOUS BALLAST CONDITIONS

The objective of the work was to produce model data to aid in the evaluation of the effect of different ballast displacements on seakeeping behavior of a typical 250,000 DWT tanker. A series of tests were made at three headings in long-crested irregular waves of two levels of severity. Additional parametric variations included four model displacement conditions and two speeds. Heave motions were of lower magnitude than would in general be expected. The most violent longitudinal motions occurred in bow seas. In general, the influence of ballast condition on motion magnitudes is not large. The incidence of propeller emergence appears worse in bow seas. Similarly, the effect of forward draft on keel emergence and the incidence of re-entry velocities greater than 17 ft/sec is very strong. It is apparent from the head sea relative motion results that the model was on the verge of supercritical operation in the model seas. This is important from the point of view of data interpretation and eventual design conclusions.

• Corporate Authors:

  Stevens Institute of Technology

  Davidson Laboratory, Castle Point Station
  Hoboken, NJ  United States  07030
• Authors:
  • Dalzell, J F
  • Klosinski, W E
• Publication Date: 1973-7

Media Info

• Features: References;
• Pagination: 42 p.

Subject/Index Terms

• TRT Terms: Ballast (Railroads); Ballast (Ships); Maneuverability; Seakeeping; Tankers; Waves
• Old TRIS Terms: Ballast condition; Irregular waves; Segregated ballast tankers
• Subject Areas: Marine Transportation; Railroads; Vehicles and Equipment;

Filing Info

• Accession Number: 00048084
• Record Type: Publication
• Source Agency: Maritime Administration
• Report/Paper Numbers: SIT-DL-73-1687 Letter Rpt
• Contract Numbers: DOC 3-36299
• Files: TRIS, USDOT
• Created Date: Oct 31 1973 12:00AM