Acoustic damper, combustor and target frequency change method for a gas turbine as well as an acoustic damper

摘要

PROBLEM TO BE SOLVED: To provide an acoustic damper that can satisfactorily damp a gas vibration of a vibration gas, without requiring a complex variable mechanism or the like for varying a tube length of an acoustic tube, even if a generation frequency such as combustion vibration is varied from a target frequency.SOLUTION: An acoustic damper D1 includes: an acoustic tube body 10 having a first flow path 11 in communication with a combustor; a separation tube 20 detachably inserted into the acoustic tube body 10, and having a second flow path 21 overlapped with at least a portion of the first flow path 11 while being inserted; and a blocking part 22 integrally provided to the separation tube 20, and blocking up a portion in the extending direction of the second flow path 21. The acoustic tube body 10 is provided with a thin wall part 14 at the insertion side of the separation tube 20. The separation tube 20 can be inserted into the thin wall part 14, and is formed into the same thickness dimension as a reduced thickness forming the thin wall part 14.