Computational Study of Wind Turbine Performance and Loading Response to Turbulent Inflow Conditions

Performance and loading patterns on wind turbine blades are analyzed using a coupled fluid/structure analysis method. Two distinct aerodynamic prediction methodologies are implemented and compared with one another. One method is a high complexity analysis that utilizes overset grid based computational fluid dynamics to model the exact geometry of turbine blades and the other method is a low complexity analysis that utilizes a free vortex wake method. Both of these aerodynamic predictions methodologies are combined with a multi-body structural analysis system to create a coupled framework that can faithfully represent the physics of rotating elastic blades. Turbulent inflow is introduced by developing interfaces that can prescribe atmospheric flow field data obtained from numerical weather prediction tools. Three different test cases are studied in order to highlight and characterize the prediction capabilities of both the approaches. In addition, the sensitivity of power and blade loading are characterized for various turbulence levels and turbine placement scenarios.