Analysis of large-scale ocean current turbine blades using Fluid-Structure Interaction and blade element momentum theory

摘要

We have developed a Fluid-Structure Interaction (FSI) procedure to investigate large-scale ocean current turbine blades by combining blade element momentum theory and finite element method. FSI procedure included changes in inflow velocity, lift coefficient and drag coefficient of blade elements. Geometric non-linearity was also considered. Three case studies were investigated to visualise effects of FSI to predict blade deflection and turbine's performance. It was observed that at an inflow velocity of 5 m/s, the flap-wise tip deflection decreased by 10% due to inclusion of FSI. This decrease was mostly due to change in lift and drag coefficients. Power coefficients were also calculated for both rigid and deformed blades. It was observed that power coefficient decreased by 2% due to blade deflection. For validation, a comparison of pressure coefficients along the chord length was made with published literature and a good correlation was observed.