Abstract: A fuel nozzle includes a center body that extends from an upstream end to a downstream end. A nozzle tip, which is fixedly coupled to the downstream end of the center body, includes an outer annular wall that has a forward end and an aft end. A solid aft wall is disposed at the aft end of the outer annular wall. The solid aft wall and the outer annular wall at least partially define a plenum. A nozzle portion, which is disposed within the plenum, includes an inner annular wall and an impingement wall. The impingement wall is spaced apart from the solid aft wall and defines a plurality of apertures configured to direct fluid to impinge upon the solid aft wall. A plurality of outlets is defined in the outer annular wall forward of the solid aft wall to direct post-impingement fluid from the nozzle tip.

Abstract: A fuel nozzle includes a center body that extends from an upstream end to a downstream end. A nozzle tip, which is fixedly coupled to the downstream end of the center body, includes an outer annular wall that has a forward end and an aft end. A solid aft wall is disposed at the aft end of the outer annular wall. The solid aft wall and the outer annular wall at least partially define a plenum. A nozzle portion, which is disposed within the plenum, includes an inner annular wall and an impingement wall. The impingement wall is spaced apart from the solid aft wall and defines a plurality of apertures configured to direct fluid to impinge upon the solid aft wall. A plurality of outlets is defined in the outer annular wall forward of the solid aft wall to direct post-impingement fluid from the nozzle tip.

Abstract: An insert for an impingement plate and an impingement plate including the insert are disclosed. The impingement plate includes a plurality of cooling holes therein. The insert includes a body including an opening extending longitudinally therethrough. The body also includes a discharge end configured for positioning in an impingement air plenum between the impingement plate and an upstream surface of a combustor cap plate; a flexible insertion end configured for insertion into a respective cooling hole of the plurality of cooling holes; and a fixation element between the discharge end and the flexible insertion end. The fixation element has an outer dimension configured to fixedly couple the body in the respective cooling hole.

Abstract: A combustor cap assembly, combustor and related method are disclosed. The combustor cap assembly includes: an impingement plate defining a plurality of impingement cooling holes with a first side of the impingement plate in fluid communication with a cooling air plenum. The assembly also includes a combustor cap plate coupled to the impingement plate, such that an impingement air plenum is defined between a second side of the impingement plate and the combustor cap plate. Tubes extend from at least a portion of the plurality of impingement cooling holes at the second side of the impingement plate and extend partially towards the combustor cap plate through the impingement air plenum. The plurality of impingement cooling holes provides for fluid communication between the cooling air plenum and the impingement air plenum through the tubes.

Abstract: An insert for an impingement plate and an impingement plate including the insert are disclosed. The impingement plate includes a plurality of cooling holes therein. The insert includes a body including an opening extending longitudinally therethrough. The body also includes a discharge end configured for positioning in an impingement air plenum between the impingement plate and an upstream surface of a combustor cap plate; a flexible insertion end configured for insertion into a respective cooling hole of the plurality of cooling holes; and a fixation element between the discharge end and the flexible insertion end. The fixation element has an outer dimension configured to fixedly couple the body in the respective cooling hole.

Abstract: A combustor cap assembly, combustor and related method are disclosed. The combustor cap assembly includes: an impingement plate defining a plurality of impingement cooling holes with a first side of the impingement plate in fluid communication with a cooling air plenum. The assembly also includes a combustor cap plate coupled to the impingement plate, such that an impingement air plenum is defined between a second side of the impingement plate and the combustor cap plate. Tubes extend from at least a portion of the plurality of impingement cooling holes at the second side of the impingement plate and extend partially towards the combustor cap plate through the impingement air plenum. The plurality of impingement cooling holes provides for fluid communication between the cooling air plenum and the impingement air plenum through the tubes.

Abstract: An injection assembly for a gas turbine combustor having a liner defining a combustion zone and a secondary combustion zone and a forward casing circumferentially surrounding at least a portion of the liner is provided. The injection assembly includes a thimble assembly and an injector unit. The thimble assembly, which is mounted to the liner, includes a thimble that extends through a thimble aperture in the liner. The injector unit, which is mounted to and extends through the forward casing, includes an injector blade that extends into the thimble. The injection assembly introduces a flow of fuel into a flow of air flowing through the thimble, such that fuel and air are injected into the secondary combustion zone in a direction transverse to a flow of combustion products from the primary combustion zone.

Abstract: A gas turbine combustor includes: a head end comprising a primary fuel nozzle; a liner defining a primary combustion zone proximate the head end and a downstream secondary combustion zone; a forward casing radially outward of and surrounding at least a portion of the liner; and an axial fuel staging system. The axial fuel staging system includes a plurality of fuel injection assemblies. Each fuel injection assembly includes a thimble assembly mounted to the liner, and an injector unit attached to the forward casing. A thimble of the thimble assembly extends through a thimble aperture in the liner. The injector unit extends through the forward casing, such that a portion of the injector unit is disposed within the thimble, and a fuel line fitting is disposed outward of the forward casing. The injector unit introduces fuel into air flowing through the thimble for injection into the secondary combustion zone.

Abstract: A thimble assembly, which directs fluid flow through a combustor liner, includes a thimble boss and a thimble. The thimble boss is mounted an outer surface of the liner and surrounds a liner opening, thus defining a thimble boss passage. The thimble is disposed through the passage and the liner opening. The thimble wall extends from an inlet portion to an outlet of the thimble. The inlet portion has a greater diameter than the outlet and defines an inlet plane and a parallel intermediate plane. A terminal plane, parallel to the intermediate plane, includes an array of points most distant from a corresponding array of points defining the intermediate plane. The thimble wall has a non-uniform length, such that the outlet of the thimble is oriented at an oblique angle relative to the terminal plane. The thimble wall may have an arcuate shape defined as one-fourth of an ellipse.

Abstract: A gas turbine combustor includes: a head end comprising a primary fuel nozzle; a liner defining a primary combustion zone proximate the head end and a downstream secondary combustion zone; a forward casing radially outward of and surrounding at least a portion of the liner; and an axial fuel staging system. The axial fuel staging system includes a plurality of fuel injection assemblies. Each fuel injection assembly includes a thimble assembly mounted to the liner, and an injector unit attached to the forward casing. A thimble of the thimble assembly extends through a thimble aperture in the liner. The injector unit extends through the forward casing, such that a portion of the injector unit is disposed within the thimble, and a fuel line fitting is disposed outward of the forward casing. The injector unit introduces fuel into air flowing through the thimble for injection into the secondary combustion zone.

Abstract: A thimble assembly, which directs fluid flow through a combustor liner, includes a thimble boss and a thimble. The thimble boss is mounted an outer surface of the liner and surrounds a liner opening, thus defining a thimble boss passage. The thimble is disposed through the passage and the liner opening. The thimble wall extends from an inlet portion to an outlet of the thimble. The inlet portion has a greater diameter than the outlet and defines an inlet plane and a parallel intermediate plane. A terminal plane, parallel to the intermediate plane, includes an array of points most distant from a corresponding array of points defining the intermediate plane. The thimble wall has a non-uniform length, such that the outlet of the thimble is oriented at an oblique angle relative to the terminal plane. The thimble wall may have an arcuate shape defined as one-fourth of an ellipse.

Abstract: An injection assembly for a gas turbine combustor having a liner defining a combustion zone and a secondary combustion zone and a forward casing circumferentially surrounding at least a portion of the liner is provided. The injection assembly includes a thimble assembly and an injector unit. The thimble assembly, which is mounted to the liner, includes a thimble that extends through a thimble aperture in the liner. The injector unit, which is mounted to and extends through the forward casing, includes an injector blade that extends into the thimble. The injection assembly introduces a flow of fuel into a flow of air flowing through the thimble, such that fuel and air are injected into the secondary combustion zone in a direction transverse to a flow of combustion products from the primary combustion zone.