Passive motion reduction of semisubmersible floating offshore wind turbine foundations

Abstract

The present work consists of numerical analysis of passive motion reduction strategies applied to semi-submersible platforms for Floating Offshore Wind (FOW) turbines. Focusing on damping structures, such as, heave plates, structures designed to damp the platforms vertical motion, by increasing the added mass and viscous damping of the device. Nevertheless, in terms of motion response, the main issue for FOW turbines is associated with pitch motion. The aim of this work is to improve understanding of heave plate influence on pitch motion, allowing for potential improvements in motion reduction in the future. The main amount of data it was obtained by NEMOH a potential flow Boundary Element Method (BEM) code. In addition, the opensource code OpenFOAM with a Reynolds-averaged Navier–Stokes equations (RANS) based solver is used to solve the flow-structure interaction of this problem and the results are compared against experimental data from the literature.