Dynamic responses of a wind turbine installation vessel under various environmental conditions including time-varying wind loads

초록

The dynamic responses of a Jack-up type wind turbine installation vessel were calculated under various sea states. Wave and current excitation forces on steel-framed structures were obtained by using the modified Morison equation. Using the wind spectrum, time-varying wind loads acting on the superstructure was also considered. In order to determine the natural frequency and standardized displacement of the structure, modal analysis was performed. The Newmark-beta method was employed to obtain time series of dynamic responses of the structure. The maximum displacement and bending stress of the structure were compared for various environmental loads. Using the reliability index of the dynamic responses, the structural safety at critical members was predicted for the effects of uncertainty of input environmental parameters.