Structure with active acoustic openings
AssigneeHexcel Corporation
InventorFumitaka Ichihashi
Life of this patent
Estimating the term…
Abstract
An acoustic structure that includes a septum having an acoustic opening which defines an open area that varies in response to changes in the velocity of noise-containing media passing through the acoustic opening. The septum includes a fixed portion and one or more movable flapper portions wherein the fixed portion and/or the flapper portion(s) include surfaces that define an acoustic opening through the septum. The acoustic opening has an open area which varies due to movement of the movable flapper(s) in response to changes in velocity of the noise-containing media that passes through the acoustic opening. The resulting septum has a relatively low non-linearity factor (NLF).
Claims19
An acoustic structure comprising a septum having an acoustic opening that varies in size in response to changes in the velocity of noise-containing media passing through said acoustic opening, said acoustic structure comprising:
- a septum comprising a fixed portion and one or more movable flapper portions that surround said acoustic opening wherein said one or more movable flapper portions are hinged to said fixed portion so that said one or more movable flapper portions move in order to vary the size of said acoustic opening in response to changes in the velocity of said noise-containing media passing through said acoustic opening.
A method for making an acoustic structure comprising a septum having an acoustic opening that varies in size in response to changes in the velocity of noise-containing media passing through said acoustic opening, said method comprising the steps of:
- providing a septum;
- forming an acoustic opening through said septum, said septum comprising a fixed portion and one or more movable flapper portions that surround said acoustic opening, wherein said one or more movable flapper portions are hinged to said fixed portion so that said one or more movable flapper portions move in order to vary the size of said acoustic opening in response to changes in the velocity of said noise-containing media passing through said acoustic opening.
A method of attenuating noise from a source wherein the velocity of noise-containing media emitted from said source is variable, said method comprising the step of locating an acoustic structure near said noise source, said acoustic structure comprising a septum having an acoustic opening that varies in size in response to changes in the velocity of said noise-containing media passing through said acoustic opening, said acoustic structure comprising:
- a septum comprising a fixed portion and one or more movable flapper portions that surround said acoustic opening wherein said one or more movable flapper portions are hinged to said fixed portion so that said one or more movable flapper portions move in order to vary the size of said acoustic opening in response to changes in the velocity of said noise-containing media passing through said acoustic opening.
Dependencies are inferred from the claim text.