Effect of interpolation on convergence of overset grids using implicit hole cutting

Accurately predicting the aerodynamic behavior of a wind farm requires high fidelity modeling of the individual components and their interaction with each other. Components in a wind farm include blades, nacelles, hubs, and towers, which possess complex geometries. The need to resolve flow structures around complex geometries has driven the research on overlapping grids commonly referred to as the overset grid approach. Exchange of information between overlapping grids is at the core of an overset framework and usually involves interpolation of data between grids. An important question to ask when using overlapping grids is how this interpolation influences the accuracy and convergence of the system. The answer depends on the behavior of the region of overlap as the overlapping meshes are refined or coarsened. This work investigates this question in detail from an implicit hole-cutting standpoint wherein a cell selection process determines computationally inactive regions based on how the meshes overlap with each other. We quantify our study using 3D problems simulating heat conduction and Low Mach fluid flow discretized using the CVFEM.