Hybrid Meshing Strategies for Horizontal Axis Wind Turbines and Wind Farm Applications
This paper was produced for the 2019 NAFEMS World Congress in Quebec Canada
A multi-block hybrid meshing strategy is introduced that adapts itself well to the challenges faced moving from the micro to the meso-scale in the wind energy industry. Starting with a wind turbine blade, we demonstrate a hybrid meshing approach that borrows many characteristics from multi-block structured methods without the topological complexity. Our technique begins with an anisotropic quadrilateral-dominant surface mesh and isolation of the blade geometry in a hybrid viscous core. Swept hexahedra and prismatic elements are used upstream and downstream, optimizing the alignment of cell face normals. This technique is highly automated and flexible enough to support design changes and the addition of features without the need to regenerate much of the computational domain. A similar strategy is used when meshing a complete wind farm including the terrain and wind turbine geometry. Starting with hexahedra, we demonstrate a technique to transition from the terrain scale to the wind turbine scale using unstructured buffer zones, resulting in a fully conformal mesh across the entirety of the wind farm. This technique has been automated to support the arbitrary placement of wind turbines for wind turbine siting applications.