Análise acoplada de uma turbina eólica offshore semissubmersível de torre central

Abstract

In recent years, the concerns about global energy to avoid severe impacts on climate change has been driving the exploration of renewable energy sources. The wind industry has developed very fast, moving from onshore to offshore in shallow water and more recent trends point to turbines in deeper waters. This work presents the design of a semi - submersible offshore wind turbine (named, OC4 DeepCWind Phase II), proposed by NREL, with a static stability study in the MAXSURF and coupled dynamic analysis in SIMA with SIMO-RIFLEX code, to study the rigid body movements, natural frequency and mooring improvement. This model is a semi-submersible of three offsets columns and a central column supporting a 5 MW wind turbine with 3 mooring lines forming angles of 120° between them. For the coupled analysis it is proposed a modeling method that allows the analysis of the system in the time domain, considering the columns of the floating unit as a rigid body connected by braces and pontoons modeled as flexible slender element. Blades, tower and mooring are also modeled as slender element.