Air-transparent selective sound silencer using ultra-open metamaterial
AssigneeTrustees of Boston University
InventorsXin Zhang, Reza Ghaffarivardavagh, Stephan Anderson
Life of this patent
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Abstract
A bilayler metamaterial silencer allows substantial fluid through the apparatus, while mitigating the propagation of sound through the apparatus, and while providing a form factor that is significantly more compact than previously-known devices. Moreover, illustrative embodiments allow a designer to specify one or both of the frequency or frequencies at which the apparatus mitigates sound propagation, and/or the bandwidth around the frequency or frequencies at which the apparatus mitigates sound propagation.
Claims20
An apparatus comprising:
- a first channel open to the propagation of a first target frequency and a second target frequency therethrough, said first channel configured to remain in a continuum state during propagation of the first target frequency and the second target frequency therethrough;
- two or more second channels, wherein
- a first of said second channels is open to the propagation of the first target frequency, and configured to resonate at the first target frequency, and
- a second of said second channels is open to the propagation of the second target frequency, and configured to resonate at the second target frequency;
- wherein said two or more second channels are disposed relative to the first channel such that:
- the first target frequency of the first of said second channels is capable of destructively interfering with the first target frequency of said first channel, and
- the second target frequency of the second of said second channels is capable of destructively interfering with the second target frequency of said first channel;
- and
- wherein the first target frequency is different from the second target frequency.
An apparatus configured to dampen an acoustic signal, the apparatus comprising:
- an outer ring defining an interior region;
- an arc-shaped resonator (“arc-resonator”) comprising a set of channels, each channel of the set of channels configured to resonate at a corresponding resonant frequency and to produce a corresponding acoustic output at its corresponding resonant frequency;
- the arc resonator disposed within the interior region to provide its acoustic output to the interior region to dampen acoustic energy within the interior region.
Dependencies are inferred from the claim text.