ON THE HYDRODYNAMIC DERIVATIVES FOR THE DIRECTIONAL STABILITY OF SHIPS IN FOLLOWING SEAS

The maneuverability of ships in a seaway may be considered from various aspects which include small and favorable wave motion. Especially, it is well known that the most dangerous condition of a ship at sea developed when the ship is in a following sea or quartering sea. In order to investigate the directional stability of ships under such circumstances, in this paper the linearized equations of motion of ship are carried out taking into account the hydrodynamic forces which act on the ship due to the presence of waves. These hydrodynamic forces are calculated using the Froude-Kriloff hypothesis and according to the conception of simple flow theory of the slender body and the quasi-static theory and the assumption that width and draft of the ships are small in comparison with the wave length. So as to consider stationary condition of the surging motion, herein the ship travels with the propagating velocity of waves at any position of the ship relative to the waves. On the other hand, a method is shown that these hydrodynamic derivatives of the model ship are experimentally measured by operating the planar motion mechanism behind the wave making board realizing stationary following sea conditions.

  • Availability:
  • Corporate Authors:

    Society of Naval Architects of Japan

    15-16, Toranomon, 1-chome, Minato-ku
    Tokyo,   Japan 
  • Authors:
    • HAMAMOTO, M
  • Publication Date: 1970

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00323602
  • Record Type: Publication
  • Source Agency: Stevens Institute of Technology
  • Files: TRIS
  • Created Date: Mar 12 1981 12:00AM