Abstract
This study investigates the effect of blade tower interaction (BTI) on power generation of a floating offshore wind turbine (FOWT) with platform pitching and surging motion. The modeled geometry is the 5MW spar-buoy FOWT developed by the National Renewable Energy Laboratory (NREL). Three CFD simulations are performed using CFDShip-Iowa V4.5:a rotor-only simulation, a full-system simulation including the tower, nacelle, and platform (TNP), and a third simulation in which the TNP is included and utilizing a larger rotor overhang.The results of these simulations are compared for analysis of the aerodynamic disruption that occurs when the blade passes in front of the tower (BTI). The present study shows that the pitching motion of the platform has little effect on shaft thrust but has a significant effect on the pressures developed near the blade and tower. The present results can potentially be used to understand the nature of the FOWT BTI for future design of turbine blade aerodynamics and structure, to help establish an empirical BTI correction model applicable to FOWT, or to aid in design of a control scheme to help mitigate power losses due to BTI.