Developments of Tuned Mass Damper for yacht structures

The comfort level on board superyachts depends on a variety of parameters all dealing with the human perception of various phenomena such vibrations, noise, ship motions and son on. In this work, the attention has been strictly devoted to vibrations and on possible solutions to reduce them. This kind of analysis is a challenging task for designers and a relevant subject for shipyards that are seriously engaged to find solutions aimed at improving the quality of their products. In this perspective, current numerical methods represent a reliable predictive tool in the design phase to identify natural frequencies of the hull and local structures. The adoption of "Tuned Mass Damper" system could be a suitable solution both at the design stage, when for the sake of weight containment heavy structure reinforcements should not be advisable and after construction when any other intervention is not possible. In this paper, the application of such device on decks of yacht is presented. TMD numerical models are created and tested to identify the main parameters characterizing a dynamic absorber, then two passive control devices, able to easily conform to the yacht deck geometry, are tuned to decrease the vibration level of the sun deck zone.