摘要 |
An annular acoustic liner for gas turbine engine ducts comprising Helmholtz resonator chambers wherein the resonator's turnable neck length and chamber depth lie on a surface which is concentric to the liner centerline. In another embodiment of the invention the liner is generally rectangular and the resonator's turnable neck length and chamber depth lie on a surface which is parallel to the duct flow. A more particular embodiment of the invention the duct is an afterburner duct which may have a rectangular or circular cross section. |