초록 ▼

A noise attenuation device having an array of quarter wave resonators which have varying mouth widths disposed adjacent an aperture or ventilation opening having a predefined width. The resonators are tuned to a resonant frequency, increasing from one face of the attenuation device to another, and s

A noise attenuation device having an array of quarter wave resonators which have varying mouth widths disposed adjacent an aperture or ventilation opening having a predefined width. The resonators are tuned to a resonant frequency, increasing from one face of the attenuation device to another, and so that the mouth widths are each greater than the width of the aperture or ventilation opening, respectively. Optionally, a second array tuned to a different frequency may be disposed on the opposite side of the aperture and the aperture may be kinked so that there is no direct line of sight through the device.

대표청구항 ▼

1. A noise attenuation device including an array of quarter wave attenuators, the array comprising a plurality of rows of tubes having a mouth width w and a length L, the rows being arranged in parallel in side by side relation, each array including tubes having different mouth widths and lengths so

1. A noise attenuation device including an array of quarter wave attenuators, the array comprising a plurality of rows of tubes having a mouth width w and a length L, the rows being arranged in parallel in side by side relation, each array including tubes having different mouth widths and lengths so that at least some of the rows of tubes in each array are tuned to a different resonant frequency to others of the rows of tubes in that array;the mouths of the tubes being contiguous a gap or ventilation opening having a width H; and wherein the width of the tubes satisfy the relation: w>H.