Aeroelastic analysis tools to predict rotor airloads must be both accurate and time effective if they are to become design tools. While the coupling of computational fluid dynamic (CFD) and comprehensive codes (CC) show ever improving predictions, such an approach is computationally expensive and is therefore impractical for use in design. Using simplified aerodynamic theories based on lifting line theory to predict airloads and inflow distributions not only allow the use of coarser models, but also require less time to compute per step than grid based CFD methods. In this project, a comprehensive code (DYMORE) is coupled with a free wake code (Maryland Free Wake). Results show a significant improvement in the aerodynamic loads predictions using the free wake model. Correlation is similar to other comprehensive models using a free wake. Loose- and tight-coupled solutions are viable; the free wake azimuthal step size appears to be the primary driver of any solution. Multiple versus single tip free wake trailers have also been studied; the computational cost for multiple trailers currently outweighs the benefits, though processes to reduce the simulation times appear practical. Multiple free wake trailers are not warranted at each airstation, but should be placed where geometric features indicate rapid aerodynamic changes may occur.
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