Analysis of tripod supported offshore wind turbines under conditions of marine growth

Offshore wind turbines are now a mature technology to produce renewable energy on vast scale, nonetheless several design and maintenance planning challenges remain. There have been attempts investigate the impact of marine growth fixed offshore turbine structures, but only few adopted whole dynamics approach. This work presents methodology capture influence dynamic response tripod substructure, supporting NREL 5 MW reference turbine, under combined loads from waves, including soil-structure interaction by means spring-to-ground model. Marine is modelled as prescribed DNV API, evaluating effects variation its thickness, roughness, distribution. It here demonstrated that thickness roughness significantly acting turbines' structures response, heterogeneity in profiles vs depth available literature lead substantially different results. Tower top displacement becomes 24% higher when grows 0 200 mm. On other hand, changes natural frequencies support structure with an increase growth's almost negligible (0.3%).