ADDED MASS AND DAMPING COEFFICIENTS FOR SHIPS HEAVING IN SMOOTH WATER

Theoretical predictions of the added mass and damping coefficient curves for ships performing small vertical oscillations in calm water are determined. A method for the inversion of a power series type transform which conformally maps a unit circle into cylinders and ship-like forms is shown. Using this method, the transform coefficients corresponding to the sections of the ships considered are obtained. From these transform coefficients, plots of the sectional added mass and damping coefficients against frequency of vibration are derived using Porter's analytical solution to the problem. Comparisons are made between these curves and Grim's predictions. Finally, by virtue of strip theory, the two-dimensional values for each cross section are integrated over the length of the ship to obtain the ship's added mass and damping coefficients at each frequency considered. No correction is made for three-dimensional effects. The resultant curves for each ship are compared with the corresponding published experimental results.

• Corporate Authors:

  Massachusetts Institute of Technology

  Department of Naval Architecture and Marine Engineering
  Cambridge, MA  United States  02139
• Authors:
  • Bermejo, R T
• Publication Date: 1965-6

Media Info

• Pagination: 75 p.

Subject/Index Terms

• TRT Terms: Amplitude (Physics); Coefficients; Damping (Physics); Mass; Ship motion
• Uncontrolled Terms: Heaving
• Old TRIS Terms: Added mass; Heave amplitude
• Subject Areas: Design; Marine Transportation;

Filing Info

• Accession Number: 00026901
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: 65-5
• Contract Numbers: MA-2720, MIT-DSR-5054
• Files: TRIS
• Created Date: Mar 2 1973 12:00AM