Patent ID: 8061476

Claim:
A sound dampening flow channel device defining at least two flow channels, each comprising an inlet opening and an outlet opening, wherein the outlet opening of each flow channel cannot be seen from the inlet opening and vice versa, wherein the flow channels are at least partly delimited by a stack of at least three single-walled acoustic energy dissipative sheets, wherein each single-walled sheet has a thickness within the range of 0.001 to 3 mm, wherein a first and a second of the single-walled sheets define between them a first flow channel and wherein the second single-walled sheet and a third of the single walled sheets define between them a second flow channel, said first, second, and third single-walled sheets each being provided with a plurality of protrusions or indentations, or combinations thereof, wherein the protrusions or indentations or combinations thereof are arranged such that fluid flowing through either of the first or second flow channel is simultaneously directed laterally and vertically from a longitudinal path, and wherein the flow channel device dampens audible sounds.