Floating offshore wind turbines can exploit the high energy
density experienced in offshore environments, with turbines now
reaching up to 15 MW in size. However, given the larger size of
these turbines and the severe offshore environment, there
remains significant challenges in motion stabilization. To
overcome these challenges, ...
Floating offshore wind turbines can exploit the high energy
density experienced in offshore environments, with turbines now
reaching up to 15 MW in size. However, given the larger size of
these turbines and the severe offshore environment, there
remains significant challenges in motion stabilization. To
overcome these challenges, the inclusion of a damper system
could be considered to reduce motions. This paper conducts a
numerical dynamic analysis of a 15 MW semi-submersible
floating offshore wind turbine under a range of environmental
conditions, informing the design criteria for such a damper
system. The study presents the findings under different
environmental loading conditions. In the first instance, the time domain results of hydrodynamic study were used to determine
the dominant characteristics. The initial study identified the
pitch motion of main concern. The simulations were carried out
under wave-only and wind-wave loading. In the wave-only
conditions study, excitation modes were observed at both the
eigenfrequency and excitation frequency, dependent on wave
conditions. When the wind loads were introduced, a large mean
pitch offset and amplitude relative to the mean offset were
observed. Within the discussion, a dual damper system is
suggested to increase the stability of the platform.