Fluid-Structure Interaction Model of a Wind Turbine Blade

Abstract

Abstract The continuous development of the wind turbine blades in expanding size and flexibility introduces significant aeroelastic effects, which are brought on by the fluid-structure interaction (FSI). These effects can lead to aeroelastic instability issues including edgewise instability and flutter, which may be fatal to the wind turbine’s blades. Therefore, designing large wind turbine blades, especially offshore wind turbine blades requires accurate FSI modeling of the wind turbine. In this study, a full-scale NREL 5MW wind turbine blade is used for modeling the coupling FSI behavior for wind turbine blades for different operating conditions. An FEA (finite element analysis) model implemented in the ANSYS Static Structural module is used to calculate the structural response under the dynamic load applied by the wind, and a CFD (computational fluid dynamics) model developed in ANSYS FLUENT is used to compute the flow behaviors of the wind on the variable cross-section of the wind turbine blade. In this simulation, the aerodynamic loads estimated from CFD modeling are translated to FEA modeling for different angles of attacks (AOA) and the wind speed as load boundary conditions at the interface between CFD and FEA. Five different operating conditions are considered where the maximum deflection of the blade is found to be in the rated operating condition. According to pertinent design requirements, maximum tensile/compressive stresses and tip deflections in each situation are found to be within the material and structural limits.