Potential hazards of wind turbine wake vortices for ultra-light sports rotorcraft

Kurzfassung

The wake of wind turbines is modeled as a tip vortex helix with a vortex strength estimated from the turbine thrust. The rotors representative of an ultra-light class autogiro and an ultra-light class coaxial helicopter are subjected to equivalent straight line vortices. For both vehicles the rotor blade flapping perturbations generated by the vortices are computed and compared to the flapping margin available. The rotor controls of the helicopter required to mitigate the vortex effects are investigated and compared to the control margin available.