Vortex Generator

A vortex generator is a small aerodynamic vane fixed to a lifting surface, such as an aircraft wing or a wind turbine blade, and set at an angle to the oncoming airflow so that it sheds a small trailing vortex off its tip. That vortex pulls faster moving air from outside the boundary layer down into the slower moving air close to the surface, which both energizes the boundary layer and encourages it to become turbulent rather than laminar, and a turbulent boundary layer resists separating from the surface far better than a laminar one does. By delaying that separation, vortex generators help prevent a wing from stalling and keep control surfaces such as flaps, ailerons, elevators and rudders effective at lower speeds, which improves an aircraft's handling during slow flight, takeoff and landing.