Shallow water effect on rolling period of ship in still water

Shallow Water' Effect on Rolling Period of Ship in Still

Water

A. Iwai

Abstract

When a ship moves in shallow water, the hydrodynamic _{phenomena around the sides of} ship cause the increasing of added mass moment of inertia of ship.

This in turn affects on natüral period of rolling of ship.

This paper relates to sorne model experiments in respect to shallow water effects upon the rolling period of ship in still water.

Tests were carried out for 3 models their principal dimensions are shown in table 1., As results of these tests, periods of rolliog are virtually increased in accordance _with decrea-sing of water depth shown in Fig. i & 2.

For example, it 'is necessary to coriect the rolling period of 20 percent or so in shallow water depth is twice the draft of ship.

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