Bundled tube fuel nozzle assembly for gas turbine combustor
A bundled tube fuel nozzle assembly for a gas turbine combustor includes: a forward plate facing a head end air plenum, an aft plate facing a combustion chamber, and premixing tubes extending from the forward plate to the aft plate. An interior side wall extends circumferentially around the first plurality of premixing tubes and defines an interior fuel plenum, and an exterior side wall extends circumferentially around the interior side wall and defines an exterior fuel plenum. Both side walls extend axially from the forward plate to the aft plate. The interior fuel plenum is in fluid communication with the exterior fuel plenum. Each premixing tube includes at least one fuel injection hole therethrough, which is in fluid communication with the interior fuel plenum. The head end air plenum is in fluid communication with the combustion chamber, via inlet ends of the premixing tubes.
1. A bundled tube fuel nozzle assembly for a gas turbine combustor, the bundled tube fuel nozzle assembly comprising:
a forward plate facing a head end air plenum, an aft plate facing a combustion chamber, a first plurality of premixing tubes extending from the forward plate to the aft plate, a second plurality of premixing tubes extending from the forward plate to the aft plate and disposed in a center region of the bundled tube fuel nozzle assembly, a partition extending circumferentially around the second plurality of premixing tubes and defining a center fuel plenum, an interior side wall extending circumferentially around the first plurality of premixing tubes and extending axially from the forward plate to the aft plate, and an exterior side wall extending circumferentially around the interior side wall and extending axially from the forward plate to the aft plate;
wherein the forward plate, the aft plate, the interior side wall, and the exterior side wall define an exterior fuel plenum;
wherein the forward plate, the aft plate, and the interior side wall define an interior fuel plenum in fluid communication with the exterior fuel plenum; the first plurality of premixing tubes comprises a radially outer group of premixing tubes; and each premixing tube of the first plurality of premixing tubes includes at least one fuel injection hole therethrough in fluid communication with the interior fuel plenum;
wherein the forward plate, the aft plate, and the partition define the center fuel plenum, the partition separating the center fuel plenum from the interior fuel plenum; the second plurality of premixing tubes comprises a radially inner group of premixing tubes; and each premixing tube of the second plurality of premixing tubes includes at least one fuel injection hole therethrough in fluid communication with the center fuel plenum; and
wherein the head end air plenum is in fluid communication with the combustion chamber, via inlet ends of the first plurality of premixing tubes.
2. The bundled tube fuel nozzle assembly of claim 1 , wherein at least one fuel conduit is coupled to the forward plate in fluid communication with the exterior fuel plenum.
3. The bundled tube fuel nozzle assembly of claim 2 , wherein the at least one fuel conduit includes a coupling conduit with a forward end having a circular cross-section and an aft end having a slot-shaped cross-section, the aft end being coupled to the exterior fuel plenum at a respective slot-shaped fuel inlet defined in the forward plate.
4. The bundled tube fuel nozzle assembly of claim 2 , wherein the at least one fuel conduit extends through an end cover that defines a forward boundary of a head end section that includes the bundled tube fuel nozzle assembly; and wherein the at least one fuel conduit is free from seals and fittings as the at least one fuel conduit extends through the end cover.
5. The bundled tube fuel nozzle assembly of claim 2 , wherein the at least one fuel conduit is a plurality of circumferentially spaced conduits, each of the plurality of circumferentially spaced conduits being in fluid communication with the exterior fuel plenum.
6. The bundled tube fuel nozzle assembly of claim 1 , wherein the interior fuel plenum and the exterior fuel plenum are fluidly connected, via fuel delivery chutes that are arranged in groups around a perimeter of the bundled tube fuel nozzle assembly; wherein the fuel delivery chutes are disposed tangentially relative to a radius of the bundled tube fuel nozzle assembly and are oriented to direct fuel flowing from the exterior fuel plenum into the interior fuel plenum between adjacent rows of premixing tubes of the first plurality of premixing tubes.
7. The bundled tube fuel nozzle assembly of claim 1 , wherein the interior fuel plenum and the exterior fuel plenum are fluidly connected, via slot-shaped openings defined in the interior side wall.
8. The bundled tube fuel nozzle assembly of claim 1 , wherein a center fuel conduit is coupled to the forward wall and is in fluid communication with the center fuel plenum.
9. The bundled tube fuel nozzle assembly of claim 1 , wherein the partition comprises a plurality of boundary premixing tubes, each of the plurality of boundary premixing tubes being in fluid communication with both the center fuel plenum and the interior fuel plenum.
10. The bundled tube fuel nozzle assembly of claim 1 , wherein the partition further comprises a plurality of air flow passages disposed between adjacent premixing tubes of the plurality of boundary premixing tubes, the plurality of air flow passages being in fluid communication with the head end air plenum.
11. The bundled tube fuel nozzle assembly of claim 10 , wherein at least one air flow passage of the plurality of air flow passages has a uniform cross-sectional shape from an inlet at the forward plate to an outlet defined in the aft plate; and wherein the outlet is fluidly coupled to one or more cooling channels defined in the aft plate.
12. The bundled tube fuel nozzle assembly of claim 1 , wherein at least one premixing tube of the first plurality of premixing tubes comprises at least one air flow passage integral with an exterior surface of the respective premixing tube and extending from the forward plate to the aft plate; and wherein the at least one air flow passage is in fluid communication with the head end air plenum and a combustion zone downstream of the aft plate.
13. The bundled tube fuel nozzle assembly of claim 12 , wherein the at least one air flow passage has an inlet defined in the forward plate and an outlet defined in the aft plate; wherein the outlet is fluidly coupled to at least one cooling channel defined in the aft plate and extending among respective outlets of neighboring premixing tubes; and wherein the at least one cooling channel terminates in a swirl funnel, the swirl funnel being in fluid communication with the combustion zone for delivering a swirling flow of air to the combustion zone.
14. The bundled tube fuel nozzle assembly of claim 1 , wherein the bundled tube fuel nozzle assembly comprises an additively manufactured body that spans an entire diameter of a head end section of the gas turbine combustor; and wherein the premixing tubes are integrally connected to the forward plate and the aft plate.
15. The bundled tube fuel nozzle assembly of claim 14 , wherein the forward plate defined by the additively manufactured body comprises ridges projecting radially outward from the forward plate in a honeycomb pattern between premixing tubes of the first plurality of premixing tubes; wherein the inlet ends of the first plurality of premixing tubes are concentric with concavities defined by the ridges and are recessed relative to the ridges; and wherein each premixing tube of the first plurality of premixing tubes has a tube wall thickness, and the ridges are configured to spread out the transitions between the tube wall thickness of the respective first plurality of premixing tubes and a thickness of the forward plate.
16. The bundled tube fuel nozzle assembly of claim 1 , wherein the exterior fuel plenum is devoid of premixing tubes.
17. A bundled tube fuel nozzle assembly for a gas turbine combustor, the bundled tube fuel nozzle assembly comprising:
a forward plate facing a head end air plenum, an aft plate facing a combustion chamber, a first plurality of premixing tubes extending from the forward plate to the aft plate, an interior side wall extending circumferentially around the first plurality of premixing tubes and extending axially from the forward plate to the aft plate, and an exterior side wall extending circumferentially around the interior side wall and extending axially from the forward plate to the aft plate;
wherein the forward plate, the aft plate, the interior side wall, and the exterior side wall define an exterior fuel plenum;
wherein the forward plate, the aft plate, and the interior side wall define an interior fuel plenum in fluid communication with the exterior fuel plenum, and each premixing tube of the first plurality of premixing tubes includes at least one fuel injection hole therethrough in fluid communication with the interior fuel plenum;
wherein the head end air plenum is in fluid communication with the combustion chamber, via inlet ends of the first plurality of premixing tubes;
wherein at least one fuel conduit is coupled to the forward plate in fluid communication with the exterior fuel plenum; and
wherein the at least one fuel conduit includes a coupling conduit with a forward end having a circular cross-section and an aft end having a slot-shaped cross-section, the aft end being coupled to the exterior fuel plenum at a respective slot-shaped fuel inlet defined in the forward plate.
18. A bundled tube fuel nozzle assembly for a gas turbine combustor, the bundled tube fuel nozzle assembly comprising:
a forward plate facing a head end air plenum, an aft plate facing a combustion chamber, a first plurality of premixing tubes extending from the forward plate to the aft plate, an interior side wall extending circumferentially around the first plurality of premixing tubes and extending axially from the forward plate to the aft plate, and an exterior side wall extending circumferentially around the interior side wall and extending axially from the forward plate to the aft plate;
wherein the forward plate, the aft plate, the interior side wall, and the exterior side wall define an exterior fuel plenum;
wherein the forward plate, the aft plate, and the interior side wall define an interior fuel plenum in fluid communication with the exterior fuel plenum via fuel delivery chutes that extend from the interior side wall into the interior fuel plenum and are disposed around a perimeter of the bundled tube fuel nozzle assembly and that are oriented tangentially relative to a radius of the bundled tube fuel nozzle assembly, and each premixing tube of the first plurality of premixing tubes includes at least one fuel injection hole therethrough in fluid communication with the interior fuel plenum;
wherein the head end air plenum is in fluid communication with the combustion chamber, via inlet ends of the first plurality of premixing tubes.