A gas turbine engine includes combustion apparatus defining a volume, a compressor, a cooling air supply feed from the compressor, and a Helmholtz resonator. The Helmholtz resonator has a neck and a chamber having an attenuation volume and which is in fluid communication with the attenuation volume, the cooling air supply feed is connected to the Helmholtz resonator and includes a valve arrangement. In a first engine operating condition, the valve arrangement is closed and the Helmholtz resonator attenuates acoustic frequencies in a first range and, in a second engine operating condition, the valve arrangement is open whereby cooling air purges the attenuation volume and the Helmholtz resonator attenuates acoustic frequencies in a second range.

A combustor for a gas turbine engine, the gas turbine engine defining a longitudinal centerline extending in a longitudinal direction, a radial direction extending orthogonally outward from the longitudinal centerline, and a circumferential direction extending concentrically around the longitudinal centerline, the combustor including: a forward liner segment; an aft liner segment disposed downstream from the forward liner segment relative to a direction of flow through the combustor, the forward and aft liner segments at least partially defining a combustion chamber; and a fence disposed between the forward and aft liner segments, wherein the fence extends in the circumferential direction, and wherein the fence extends into the combustion chamber along the radial direction.

A combustor component of a combustor for combusting fuel to produce a combustion gas includes a combustion cylinder forming a passage for the combustion gas, a first acoustic device which internally includes a first cavity communicating with the passage via a first through hole formed in the combustion cylinder, a second acoustic device which is located on a radially outer side of the first acoustic device so as to cover the first acoustic device, and internally includes a second cavity communicating with the passage via a second through hole formed in the combustion cylinder, and a first communication passage causing the first cavity and an outer space of the combustion cylinder to communicate with each other without via the first through hole and the second cavity.

A gas turbine engine that is configured to mitigate fuel coupled dynamics. The engine includes a combustor, a fuel delivery system, a fuel manifold line; and a device configured to mitigate fuel coupled dynamics. The device is attached to the fuel manifold line and includes a housing and a reflector. The housing includes a wall and the wall defines a housing surface that is configured to reflect waves conducted by fuel within the fuel delivery system. The reflector is positioned within the housing and the reflector includes an anterior surface that is configured to reflect waves conducted by fuel within the fuel delivery system such that wave the reflected waves can strike the surface.

A structure for damping at a fluid manifold assembly for an engine is generally provided. The fluid manifold assembly includes a first walled conduit defining a first fluid passage therewithin. A flow of fluid defining a first frequency is permitted through the first fluid passage. A second walled conduit includes a pair of first portions each coupled to the first walled conduit. A second portion is coupled to the pair of first portions. A second fluid passage is defined through the first portion and the second portion in fluid communication with the first fluid passage. The flow of fluid is permitted through the second fluid passage at a second frequency approximately 180 degrees out of phase from the first frequency.

An acoustic damper for a rotary machine includes at least one wall, at least one inlet, at least one outlet, at least one separating wall, and at least one neck. The wall extends from the back side of a combustor front panel and defines a damping chamber. The inlet is defined within the wall and is oriented to channel a flow of air into the damping chamber. The outlet is defined within the back side of the front panel. The separating wall is oriented to separate the damping chamber into a first volume and a second volume. The first volume of the damping chamber is configured to damp an acoustic pressure oscillation at a first frequency. The second volume of the damping chamber is configured to damp the acoustic pressure oscillation at a second frequency. The neck extends through the separating wall and is axially offset from the outlet.

A resonator formed as a ring for a gas turbine combustion chamber, includes an outer shell and an inner shell, wherein one part of a hot gas channel of the gas turbine combustion chamber is delimited by the inner shell, wherein at least one Helmholtz resonator is arranged between the outer shell and the inner shell.

A spacer for a fluid nozzle can include a body configured to fit within a sheath of the fluid nozzle such that a fluid tube positioned within the sheath is held bent over its longitudinal dimension by the body thereby altering a natural frequency of the fuel tube compared to if the fuel tube were not held bent.

An acoustic attenuator comprises a first attenuation unit, a second attenuation unit, a welded section, and a communication part. A first acoustic damper is provided on an outer surface of a first acoustic liner, which faces toward a side opposite from an object, to form a first damper space that communicates with an internal space of the object. The second attenuation unit is attached to an outer surface of the object. The welded section is provided at least between the first acoustic damper and a second acoustic damper. The welded section secures the second attenuation unit to the first acoustic liner. The communication part is disposed in a position farther from an outer surface of the object than the welded section, allowing communication between the first damper space and a second damper space.

Combustor systems are provided. For example, a combustor system comprises a combustor having forward and aft ends and including annular inner and outer liners that each extend generally along an axial direction and define a combustion chamber therebetween. The combustor system also comprises a fuel nozzle having an outlet defined in an outlet end of the fuel nozzle and including a pilot swirler. The outlet is positioned at the forward end of the combustor to direct a fuel-air mixture into the combustion chamber. The combustor system further comprises a main mixer attached to the outlet end of the fuel nozzle and extending about the outlet. A total combustor airflow through the combustor comprises a pilot swirler airflow that is greater than about 14% of the total combustor airflow and a main mixer airflow that is less than about 50% of the total combustor airflow.