Patent ID: 7837147
Filing Date: 2010-11-23
Classification: B29C,B29D,B29K,B32B,B64C,F16F,Y02T,Y10T

Abstract:
1. A noise reduction system comprising: an aircraft skin; a stiffener having a first stiffener portion attached to the aircraft skin and a second stiffener portion offset from the aircraft skin, the second stiffener portion having a first width; a strip of auxetic core supported by the second stiffener portion, the strip of auxetic core having a second width that is at least approximately the same as the first width, the strip of auxetic core further having a first surface facing at least approximately toward the stiffener and a second surface facing at least approximately away from the stiffener; a constraining layer positioned toward the second surface of the auxetic core; and a damping layer sandwiched between the constraining layer and the second surface of the auxetic core.