EFFECT OF BALLAST IN TANKER DESIGN

Tanker design is undertaken in a conventional manner, including consideration of the following: resistance and weight estimates; economic analysis; application of IMCO Regulations. A literature survey was conducted to develop the principal dimensions of the designs. Deadweights for the selected designs were approximately: 70,000 L.T.; 120,000 L.T.; 200,000 L.T.; 340,000 L.T. It has been determined that the boundary line between volume-limited ships and weight-limited ships lie somewhere between deadweights of 120,000 L.T. and 200,000 L.T. To meet IMCO Requirements it was necessary to modify some of the designs--the 70,000 DWT and the 120,000 DWT. A seakeeping analysis was conducted for the 120-design and its modified version. The results of this analysis showed that IMCO Regulations should be modified in such a way as to include seakeeping considerations for the determination of the minimum amount of ballast, instead of the currently used which is based in the restraint of dimensions. A propeller experiment was conducted to investigate the propulsive efficiency characteristics of a propeller when it is partially submerged. Results of this experiment have shown that the efficiency of a propeller partially submerged decreases very little, therefore, the validity of the IMCO requirement for a fully immersed propeller is questioned.

  • Corporate Authors:

    Massachusetts Institute of Technology

    Department of Naval Architecture and Marine Engineering
    Cambridge, MA  USA  02139
  • Authors:
    • Mossone, RAZ
  • Publication Date: 1974-5

Subject/Index Terms

Filing Info

  • Accession Number: 00071682
  • Record Type: Publication
  • Source Agency: Massachusetts Institute of Technology
  • Report/Paper Numbers: MS Degree
  • Files: TRIS
  • Created Date: Nov 12 1974 12:00AM