Abstract: A wind turbine blade for use in a wind energy system comprises a blade body having a trailing edge and a leading edge, and a plurality of bristles disposed on an outer surface of said blade body. The bristles are typically attached to said blade body in the vicinity of said trailing edge and serve to reduce noise caused by the airflow around the blade during operation.

Abstract: A slat is selectively extended from a main wing body, with a concave rear surface of the slat facing a convex forward nose surface of the wing body, with a slat gap therebetween. At least one row of flexible bristles is movably arranged relative to the lower rear edge of the slat, to flexibly protrude up into the slat air gap. At least one row of flexible bristles is movably arranged along the upper rear edge of the slat to extend rearwardly over the slat air gap and the upper surface of the main wing body. The flexible bristles are flexibly self-positioning and self-contouring due to the aerodynamic forces acting thereon, to improve the air flow conditions through the slat gap, separate the slat gap airflow from an entrapped eddy vortex on the concave rear surface of the slat, and thereby reduce the aerodynamic noise generated along the slat gap.

Abstract: A slat is selectively extended from a main wing body, with a concave rear surface of the slat facing a convex forward nose surface of the wing body, with a slat gap therebetween. At least one row of flexible bristles is movably arranged relative to the lower rear edge of the slat, to flexibly protrude up into the slat air gap. At least one row of flexible bristles is movably arranged along the upper rear edge of the slat to extend rearwardly over the slat air gap and the upper surface of the main wing body. The flexible bristles are flexibly self-positioning and self-contouring due to the aerodynamic forces acting thereon, to improve the air flow conditions through the slat gap, separate the slat gap airflow from an entrapped eddy vortex on the concave rear surface of the slat, and thereby reduce the aerodynamic noise generated along the slat gap.

Abstract: A separating surface (6) is arranged on an additional airfoil for an aircraft main wing (3). The separating surface (6) is hinged on the main wing (3) and can be extended. The separating surface (6) extends in the direction of the main wing (3) and is arranged along a separation flow line (9) between a vortex flow region (8) and a slat cove flow (7) of the air flowing between the additional airfoil and the main wing (3).