摘要 |
A liner assembly (22) includes a plurality of aligned passages (28) providing a large open area combined with openings (30) much smaller than a length (36) of the passages (28). The plurality of passages (28) are disposed parallel with each other and include an opening (30) transverse to incident sound waves. The passages (28) are separated by walls (32) and are blocked at an end distal from the openings (30). Sound waves incident on a face of the liner (22) enter the passages (28) and are dissipated by viscous losses. Sound energy is further dissipated as thermal energy to the walls (32) of the passages (28). The long narrow passages (28) provide the desired visco-thermal losses for sound energy in a broad frequency range. |