Preliminary Performance Assessment of a Twin-rotor Horizontal Axis Wind Turbine Using Fast Aerodynamic Methods

Kurzfassung

The present work describes a simplified computational setup for the preliminary estimation of the power output of an overlapping twin-rotor horizontal axis wind turbine. A blade element theory based rotor code coupled to a lifting-line vortex-lattice downwash model is used for the prediction of the turbine behavior. The relation of power output versus rotor overlap of the twin-rotor configuration is compared to a single isolated rotor at identical operation conditions. An acceptable amount of rotor overlap in terms of power loss is found to allow for a close spacing. An analysis of the wake-induced velocity seeks to shed some light on the aerodynamic interaction.