INSTABILITY OF SHIP MOTIONS IN LONGITUDINAL WAVES RESULTING FROM NONLINEAR COUPLING

Abstract

An investigation was made of the effect of certain nonlinear coupling terms on the heave-pitchroll motions of a ship moving in longitudinal waves (either head or following waves). Linear damping terms were retained in the analysis because when forced ship motions under wave excitation are studied, the damping terms are essential elements of the problem. The analysis for the heave-pitch-roll system showed the existence of a type of instability such that the responses in pitch or roll may grow without bound even when the effect of damping was taken into account because of nonlinear coupling between heave and pitch and between heave and roll. This is in contrast to the results obtained from the linear theory in which, because of the presence of damping, all the responses are finite. (Author)

Document Details

Document Type
Technical Report
Publication Date
May 01, 1961
Accession Number
AD0262696

Entities

People

  • C.s. Hsu

Organizations

  • University of California, Berkeley

Tags

Communities of Interest

  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Contrast
  • Couplings
  • Excitation
  • Fittings
  • Instability
  • Mental Processes
  • Motion
  • Ship Motion

Fields of Study

  • Engineering

Readers

  • Control Systems Engineering.