Patent ID: 8459597
Filing Date: 2013-06-11
Classification: B64D,F02C,F02K,F05D

Abstract:
1. A method for preventing separation of air flow from an inner surface of a nacelle for a gas turbine engine comprising the steps of: communicating air along the inner surface of the nacelle with a noise attenuation structure, wherein the noise attenuation structure comprises a face sheet including a plurality of openings communicating with a plurality of cells with uninterrupted solid walls, and a back sheet supporting the plurality of cells and including a plurality of openings in communication with the plurality of cells; generating a pressure differential to draw a portion of air flow along the inner surface through the noise attenuation structure and into a plenum in communication with the back sheet and each of the openings in the back sheet that correspond with the plurality of cells; and exhausting the portion of air flow drawn through the noise attenuation structure out of the nacelle with a vacuum source that draws air through the noise attenuation structure and away from the inner surface of the nacelle.