Model tests for determining critical vibrations of the rudderpost of a “Mariner” rudder 1

Abstract

Model tests have been executed to determine the bending and torsional vibration phenomena in the rudderpost of a “Mariner” rudder.

Discussion of the laws of mechanical similarity which must be satisfied in these model tests.

It appears from the measurements of the tension amplitudes that the excitation of the rudder by the helicoidal tip vortices of the propeller is not exactly harmonic but that it also contains a “noise” element.

The added mass of the rudder could be established from the measurements.