A RATIONAL STRIP THEORY OF SHIP MOTIONS: PART II

The exact ideal-fluid boundary-value problem is formulated for the diffraction of head-sea regular waves by a restrained ship. The problem is then simplified by applying four restrictions: 1) the body must be slender; 2) the wave amplitude is small; 3) the wave length of the incoming waves is of the order of magnitude of the transverse dimensions of the ship; 4) the forward speed is zero or it is on the order of e exp(1/2-a) for a between O and 1/2 where e is the slenderness parameter. The problem is solved by using matched asymptotic expansions. The result shows that the wave is attenuated as it propagates along the ship. The result is not expected to be valid near the bow or stern of the ship. The pressure distribution and force distribution along a ship model with circular cross-sections have been calculated. The total force on the ship has been compared with the value predicted by the Khaskind relation. The agreement is good. The experimental and theoretical pressure distribution along a prolate spheroid have been compared. The predicted attenuation of the peak pressure is very well confirmed by the experiments. In addition, theory and experiment agree that the peak pressure near the ship generally leads the Froude-Kriloff pressure peak by 45 degrees.

• Corporate Authors:

  University of Michigan, Ann Arbor

  Department of Naval Architects and Marine Engineers
  Ann Arbor, MI  United States  48109
• Authors:
  • Faltinsen, O
• Publication Date: 1971-12

Media Info

• Features: References;
• Pagination: 137 p.

Subject/Index Terms

• TRT Terms: Ship motion; Thinness; Wave resistance; Waves
• Old TRIS Terms: Regular waves; Slender bodies
• Subject Areas: Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00032746
• Record Type: Publication
• Source Agency: University of Michigan, Ann Arbor
• Report/Paper Numbers: 113
• Files: TRIS
• Created Date: Apr 28 1972 12:00AM