Development of a Three-Dimensional Viscous-Inviscid coupling Method for Wind Turbine Computations

MIRAS, a computational model for predicting the aerodynamic behavior of wind turbine blades and wakes subject to unsteady motions and viscous effects has been developed. The model is based on a three-dimensional panel method using a surface distribution of quadrilateral singularities with a Neumann no penetration condition.

Viscous effects inside the boundary layer are taken into account through the coupling with the quasi-3D integral boundary layer solver Q3UIC. A free-wake model is employed to simulate the vorticity released by the blades in the wake. In this paper simulations are presented in an effort to validate the code for three different rotor geometries, the MEXICO experiment rotor, the DELFT rotor and the NREL 5MW rotor.