Patent ID: 6821090
Filing Date: 2004-11-23
Classification: B64C,Y02T,Y10S

Abstract:
An active control device for improving air flow characteristics in a vicinity of an airfoil, the airfoil having an outer aerodynamic surface and an interior volume, the airfoil having a chord of predetermined length, the aerodynamic surface comprising a leading edge and a trailing edge, the active control device comprising:a plurality of apertures disposed on the outer aerodynamic surface, said plurality of apertures communicating the outer aerodynamic surface to the interior volume and all of said plurality of apertures being disposed closer to said trailing edge than to said leading edge; a chamber disposed within the interior volume, said chamber defining a volume in fluid communication with said apertures; a plurality of diaphragms defining a wall of said chamber, said plurality of diaphragms each being movable between a first position and a second position, wherein movement of each of said diaphragms from said first position to said second position pushes air present in the interior volume through said plurality of apertures and but of the interior volume, and wherein movement of each of said diaphragms from said second position to said first position draws air through said plurality of apertures and into the interior volume; a controller operatively coupled to said plurality of diaphragms, said controller controlling movement of said plurality of diaphragms; and first and second sensors operatively coupled to said controller, said first and second sensors disposed on the aerodynamic surface, said first and second sensors measuring a flow characteristic of air proximal to said first and second sensors; a total number of said plurality of apertures corresponding to a total number of said plurality of diaphragms, and each of said plurality of diaphragms pushing and drawing air through a corresponding one of said plurality of apertures; wherein said controller regulates an oscillation amplitude of at least one of said plurality of diaphragms in response to said flow characteristic of air measured by said first and second sensors.