DEVELOPMENT OF THE SMALL-SIZE DYNAMIC DAMPER

The development of a small-size dynamic damper to reduce the vibration of main fittings and local structure on ships is described. The authors manufactured the passive mass damper which consists of a plate spring with sliding support and removable viscous-damper, and confirmed the vibration characteristics by an experiment using a test structure and exciter. These were applied to actual ship fitting to verify the efficiency. The following conclusions were obtained: (1) The required specifications as a damper for the fittings and local structure of a ship were cleared. (2) The performance of the newly developed passive type damper was confirmed to satisfy the required specification by the experiment using the test structure and exciter. (3) From the experiments on the ships, it was confirmed that the vibration of a funnel was reduced to about 1/2.9 by fitting the dynamic damper without viscous-damper and the vibration of the support structure for the cell guides was reduced to about 1/5.5 by fitting the dynamic damper with a viscous damper.