Motions of ship in oblique waves

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Motions of Ship in Oblique Waves By Shin Tamiya, Member

Abstract

Assuming that the centre of gravity of a ship advances horizontally with a uniform velocity, the equations of general motions of the ship n oblique sine waves are obtained. From the

solution of the equations, we have found that the effect of the exciting moment and accordingly the angles of oscillations vary complicatedly with respect to the angle of encounter when the wave length is short or comparable with the length of the ship.

lt is also revealed that the interactions of rolling, pitching and yawing are small.

Making use of the results as to the motions in regular waves, the author has worked out an illustrative calculation of pitching and rolling angles in irregular seas and obtained some re-markable results which are, however, ordinarily experienced on board.

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