CALCULATION OF THE SECOND ORDER MEAN FORCE ON A SHIP IN OBLIQUE SEAS

A design tool is developed for use by engineers for the calculation of the mean added resistance or drift force on an elongated body such as a ship in a seaway. Only forces arising from wave-ship motion interaction or wave reflection are considered and developed in a form suitable for a computer program. This procedure allows computation of the mean second order force from first order quantities already known in strip theory of ship motions. Regular wave computer results generated by the MIT 5-D motions program for the Mariner cargo vessel are presented and compared with experiment, including a set of new beam seas experiments. Comparison is also made with published results from two other programs. The extension of the regular wave theory to an irregular long-crested seaway and then to a short-crested seaway is outlined. Finally, six representative sea spectra are used in a brief design analysis for the Mariner at service speed.

• Corporate Authors:

  Massachusetts Institute of Technology

  Department of Naval Architecture and Marine Engineering
  Cambridge, MA  United States  02139
• Authors:
  • Erb, P R
• Publication Date: 1977-5

Subject/Index Terms

• TRT Terms: Coefficients; Computer programs; Fluid resistance; Reflection; Ship motion; Ships; Waves
• Old TRIS Terms: Wave reflection coefficient; Wave theory
• Subject Areas: Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00168235
• Record Type: Publication
• Source Agency: Massachusetts Institute of Technology
• Report/Paper Numbers: MS Thesis
• Files: TRIS
• Created Date: Jan 30 1978 12:00AM