Abstract: A fuel nozzle includes an outer body extending parallel to a centerline axis, having a generally cylindrical exterior surface, forward and aft ends, and a plurality of openings through the exterior surface. The fuel nozzle further includes an inner body inside the outer body, cooperating with the outer body to define an annular space, and a main injection ring inside the annular space, the main injection ring including fuel posts extending therefrom. Each fuel post is aligned with one of the openings and separated from the opening by a perimeter gap which communicates with the annular space. There is a circumferential main fuel gallery in the main injection ring, and a plurality of main fuel orifices, wherein each orifice communicates with the main fuel gallery and extends through one of the fuel posts.

Abstract: A fuel injection system for use in a combustor of a turbine engine includes a mixer assembly including a mixer housing and a fuel nozzle assembly positioned radially inward of the mixer housing. The fuel nozzle assembly includes a substantially annular fuel injection housing and a substantially annular main fuel injector coupled to the fuel injection housing. The main fuel injector includes a body, a fuel delivery passage defined in the body, a swirl chamber defined in the body downstream of the fuel delivery passage, and a plurality of circumferentially-spaced fuel metering slots defined in the body and coupled in flow communication with and between the fuel delivery passage and the swirl chamber.

Abstract: A fuel injector for a gas turbine engine including an outer sleeve. An upstream end of the outer sleeve defines an inlet opening and a downstream end defines an exit opening, each of which defined within the outer sleeve. The outer sleeve defines a radial opening extended therethrough along the radial direction. At least a portion of the outer sleeve defines a plurality of grooves. The outer sleeve defines a fuel conduit through at least a portion of the outer sleeve outward of the plurality of grooves along the radial direction from the fuel injector centerline. The fuel conduit defines a fuel injection opening inward along the radial direction of the radial opening defined through the outer sleeve. A first member of an arm is coupled to the outer sleeve. A second member of the arm is contoured defining a fuel injection port generally concentric to the fuel injector centerline.

Abstract: A method and structure for operating a combustion system of a gas turbine engine to mitigate low frequency combustion acoustics is generally provided. The method includes flowing an oxidizer through a fuel nozzle passage defining an inner wall and an outer wall, in which each of the inner wall and the outer wall are contoured from a first radius to a second radius smaller than the first radius; flowing the oxidizer at a higher axial velocity at the inner wall relative to the outer wall upstream of a fuel injection port; flowing a fuel through the fuel injection port to the fuel nozzle passage to mix with the flow of oxidizer to produce a fuel-oxidizer mixture; and igniting the fuel-oxidizer mixture downstream of the fuel injection port.

Abstract: A combustor assembly for a turbine engine and method for cooling a portion of the combustor assembly, the combustor assembly comprising a combustor liner defining a combustion chamber with an inlet and an outlet, a fuel dome located in the inlet and having a wall adjacent at least a portion of the combustor liner, and a deflector overlying and spaced from at least a portion of the wall.

Abstract: A combustor liner, a gas turbine engine including a combustor having the combustor liner, and a method for regulating jet wakes in the combustor are disclosed. The combustor liner includes a panel, at least one first through-hole, and a plurality of second through-holes including first and second set of through-holes. The at least one first through-hole is disposed on a section of the panel in a first row. The plurality of second through-holes is disposed on the section along axial and circumferential directions and arranged adjacent to the at least one first through-hole. The first set and the second set of through-holes are arranged in a second row and a third row respectively. The first, second, and third rows extend along the circumferential direction. The at least one first through-hole and the plurality of second through-holes collectively cover circumferential plane of the section along the first, second, and third rows.

Abstract: A system and method for operating a combustion system comprising a fuel nozzle defining at least one main fuel circuit and at least one pilot fuel circuit is generally provided. The method includes determining an overall flow of fuel, the overall flow of fuel defining a sum total fuel through the main fuel circuit and the pilot fuel circuit; determining a plurality of ranges of ratios of main fuel flow through the main fuel circuit versus pilot fuel flow through the pilot circuit from the overall flow of fuel, wherein each range of ratios is based on a combustion criterion different from one another; determining a resultant range of ratios of main fuel flow versus pilot fuel flow based on a hierarchy of combustion criteria, wherein the hierarchy of combustion criteria provides a priority ranking of the combustion criterion; and flowing the overall flow of fuel to the main fuel circuit and the pilot fuel circuit based on the resultant range of ratios of main fuel flow versus pilot fuel flow.

Abstract: Various embodiments include a trapped vortex combustor and a method for operating trapped vortex combustor. In one embodiment, the trapped vortex combustor comprises a trapped vortex combustion zone and at least one secondary combustion zone disposed downstream of the trapped vortex combustion zone. The trapped vortex combustion zone is operable to receive and combust a first fuel and a first air and produce a first combustion product flowing toroidally therein. The at least one secondary combustion zone is operable to receive and combust the first combustion product and at least one second injection consisting of fuel and/or air and produce at least one second combustion product therein. The combustor may reduce the residence time of the highest temperature combustion products and achieve the lower NOx emission.

Abstract: Fuel nozzle assemblies are provided. For example, a fuel nozzle assembly for a combustor system comprises a fuel nozzle having a pilot swirler and an outlet defined in an outlet end, as well as a main mixer attached to the outlet end and extending about the outlet. A total combustor airflow through the combustor system comprises a pilot swirler airflow that is greater than about 14% and a main mixer airflow that is less than about 50% of the total combustor airflow. In further embodiments, the fuel nozzle also comprises main and pilot fuel injectors that each are configured to receive a portion of a fuel flow to the fuel nozzle. The fuel nozzle provides less than about 80% of the fuel flow to the main fuel injector at a high power operating condition of a gas turbine engine in which the fuel nozzle assembly is installed.

Abstract: An aft heat shield for a fuel nozzle tip includes: an annular shield wall; an annular shield flange extending radially outward from an aft end of the shield wall; an annular baffle flange surrounding the conical section, and disposed such that an axial gap is defined between the shield flange and the baffle flange, the baffle flange including a radially outer rim extending axially forward therefrom; and a plurality of impingement cooling holes passing through the baffle flange and oriented to as to direct air flow towards the shield wall.

Abstract: The present disclosure is directed to a fuel nozzle assembly for a gas turbine engine. The fuel nozzle assembly includes a centerbody extended along a nozzle centerline axis and generally concentric thereto and an outer sleeve surrounding the centerbody and extended along the nozzle centerline axis and generally concentric thereto. The centerbody defines an outer wall extended at least partially along the nozzle centerline axis in which the centerbody defines a first fuel passage therewithin and one or more first fuel exit openings through the outer wall. Each first fuel exit opening is discrete from another along the outer wall. The outer sleeve and centerbody together define a first air passage therebetween. The first fuel passage and the first fuel exit opening are in fluid communication with the first air passage.

Abstract: A fuel nozzle is provided for a gas turbine engine, and can include a pilot fuel injector having an axially-elongated, inner pilot centerbody wall and an outer pilot centerbody wall, with the axially-elongated, inner pilot centerbody wall extending from an upstream end to an annular fuel passage defining the downstream end of the pilot fuel injector. The fuel passage intersects with the inner pilot centerbody wall at a pilot fuel metering orifice. The fuel nozzle also includes a pilot fuel film surface downstream from the annular fuel passage and an annular splitter surrounding the pilot fuel injector. The annular splitter comprises, in axial sequence: an upstream section, a splitter throat having a diameter that is larger than a downstream diameter defined by the pilot fuel film surface, and a downstream diverging surface having an average diverging angle of about 24° to about 40° in relation to a centerline axis.

Abstract: A fuel nozzle for a gas turbine engine includes an outer body defining a plurality of openings in an exterior surface. The fuel nozzle also includes a main injection ring disposed at least partially inside the outer body. The main injection ring includes a plurality of fuel posts extending into or through the plurality of openings of the outer body. The plurality of fuel posts include an LP fuel post defining a main fuel orifice, a top surface, and a scarf, the scarf of the LP fuel post extending in the top surface in a first direction relative to the centerline axis away from the main fuel orifice. The plurality of fuel posts also include an HP fuel post defining a main fuel orifice, a top surface, and a scarf, the scarf of the HP fuel post extending in the top surface fin a second direction relative to the centerline axis away from the main fuel orifice, the second direction being at least ninety degrees different than the first direction.

Abstract: An aft heat shield for a fuel nozzle tip includes: an annular shield wall; an annular shield flange extending radially outward from an aft end of the shield wall; an annular baffle flange surrounding the conical section, and disposed such that an axial gap is defined between the shield flange and the baffle flange, the baffle flange including a radially outer rim extending axially forward therefrom; and a plurality of impingement cooling holes passing through the baffle flange and oriented to as to direct air flow towards the shield wall.

Abstract: A combustor for a turbine engine includes an inner combustion liner and an outer combustion liner together defining at least in part an interior. The interior includes a combustion chamber and a main portion. The combustor also includes an inlet combustion liner at least partially defining the combustion chamber of the interior and including an inlet assembly. The inlet assembly includes at least two cavity air tubes arranged along the axial direction, each cavity air tube extending between an inlet and an outlet, the outlet of each cavity air tube in airflow communication with the combustion chamber for providing the combustion chamber with a flow of air.

Abstract: A pilot fuel injector is provided for a fuel nozzle of a gas turbine engine. The pilot fuel injector can include an axially-elongated, inner pilot centerbody wall extending from an upstream end to a downstream end, with the axially-elongated, inner pilot centerbody wall having a diverging-converging orientation with respect to a centerline axis to define a hollow tube having an upstream diameter, a throat, and a downstream diameter such that the throat has an inner diameter that is less than both of the upstream diameter and the downstream diameter. The pilot fuel injector also includes a center air circuit positioned at the upstream end, and an annular fuel passage defining the downstream end and intersecting with the centerbody wall at a pilot fuel metering orifice. A pilot fuel film surface is downstream from the annular fuel passage.

Abstract: A fuel injection system for use in a combustor of a turbine engine includes a mixer assembly including a mixer housing and a fuel nozzle assembly positioned radially inward of the mixer housing. The fuel nozzle assembly includes a substantially annular fuel injection housing and a substantially annular main fuel injector coupled to the fuel injection housing. The main fuel injector includes a body, a fuel delivery passage defined in the body, a swirl chamber defined in the body downstream of the fuel delivery passage, and a plurality of circumferentially-spaced fuel metering slots defined in the body and coupled in flow communication with and between the fuel delivery passage and the swirl chamber.

Abstract: A fuel nozzle includes an outer body extending parallel to a centerline axis, having a generally cylindrical exterior surface, forward and aft ends, and a plurality of openings through the exterior surface. The fuel nozzle further includes an inner body inside the outer body, cooperating with the outer body to define an annular space, and a main injection ring inside the annular space, the main injection ring including fuel posts extending therefrom. Each fuel post is aligned with one of the openings and separated from the opening by a perimeter gap which communicates with the annular space. There is a circumferential main fuel gallery in the main injection ring, and a plurality of main fuel orifices, wherein each orifice communicates with the main fuel gallery and extends through one of the fuel posts.

Abstract: A pilot fuel injector is provided for a fuel nozzle of a gas turbine engine. The pilot fuel injector can include an axially-elongated, inner pilot centerbody wall extending from an upstream end to a downstream end, with the axially-elongated, inner pilot centerbody wall having a diverging-converging orientation with respect to a centerline axis to define a hollow tube having an upstream diameter, a throat, and a downstream diameter such that the throat has an inner diameter that is less than both of the upstream diameter and the downstream diameter. The pilot fuel injector also includes a center air circuit positioned at the upstream end, and an annular fuel passage defining the downstream end and intersecting with the centerbody wall at a pilot fuel metering orifice. A pilot fuel film surface is downstream from the annular fuel passage.

Abstract: A fuel nozzle is provided for a gas turbine engine, and can include a pilot fuel injector having an axially-elongated, inner pilot centerbody wall and an outer pilot centerbody wall, with the axially-elongated, inner pilot centerbody wall extending from an upstream end to an annular fuel passage defining the downstream end of the pilot fuel injector. The fuel passage intersects with the inner pilot centerbody wall at a pilot fuel metering orifice. The fuel nozzle also includes a pilot fuel film surface downstream from the annular fuel passage and an annular splitter surrounding the pilot fuel injector. The annular splitter comprises, in axial sequence: an upstream section, a splitter throat having a diameter that is larger than a downstream diameter defined by the pilot fuel film surface, and a downstream diverging surface having an average diverging angle of about 24° to about 40° in relation to a centerline axis.