Abstract: A fuel injection system for a gas turbine engine includes a first plurality of fuel nozzles arrayed in a circular pattern. Each of the nozzles in the first plurality of fuel nozzles includes a first airflow area defined therethrough. A second plurality of fuel nozzles radially inward from the first plurality of fuel nozzles. Each of the nozzles in the second plurality of fuel nozzles includes a second airflow area defined therethrough. The first airflow area is larger than the second airflow area. A third plurality of fuel nozzles can be radially inward from the second plurality of fuel nozzles. Each of the nozzles in the third plurality of fuel nozzles can include a third airflow area defined therethrough. The second airflow area can be larger than the third airflow area.

Abstract: A system includes a combustor. The combustor has a combustor wall with a combustor dome at an upstream end of the combustor wall, and an outlet at a downstream end of the combustor wall opposite the upstream end. The combustor wall includes an inner wall portion and an outer wall portion defining an interior of the combustor therebetween. Each of the inner wall portion and outer wall portion extends from the combustor dome to the downstream end of the combustor wall. The combustor wall includes an air cooling passage embedded inside at least one of the inner wall portion and the outer wall portion. The air cooling passage extends from the upstream end of the combustor wall to the downstream end of the combustor wall.

Abstract: A system includes a combustor. The combustor has a combustor wall with a combustor dome at an upstream end of the combustor wall, and an outlet at a downstream end of the combustor wall opposite the upstream end. The combustor wall includes an inner wall portion and an outer wall portion defining an interior of the combustor therebetween. Each of the inner wall portion and outer wall portion extends from the combustor dome to the downstream end of the combustor wall. The combustor wall includes an air cooling passage embedded inside at least one of the inner wall portion and the outer wall portion. The air cooling passage extends from the upstream end of the combustor wall to the downstream end of the combustor wall.

Abstract: A method includes forming fluid conduit inside a heat shield in an additive manufacturing process, removing powder from an interior passage of the fluid conduit and from an insulation gap defined between the fluid conduit and the heat shield, separating the heat shield and fluid conduit from the build platform, and shifting the fluid conduit to a shifted position relative to the heat shield. The method includes securing the fluid conduit to the heat shield in the shifted position.

Abstract: A fuel injector for an exhaust heater includes a cover and an air blast nozzle. The cover has a nozzle seat, a fuel inlet, and an air inlet, the nozzle seat arranged along a flow axis. The air blast nozzle is seated in the nozzle seat and has a unibody. The air blast nozzle unibody is in fluid communication with the fuel inlet and the air inlet arranged along the flow axis to port fuel and air into a combustion volume, e.g., to heat a stream of exhaust gas flowing between an engine and a catalytic reactor by combustion with fuel introduced through the fuel inlet and air introduced through the air inlet.

Abstract: A torch ignitor system for a combustor of a gas turbine engine includes a torch ignitor, the torch ignitor including a combustion chamber oriented about a torch axis, the combustion chamber having axially upstream and downstream ends defining a flow direction through the combustion chamber, along the axis. The torch ignitor includes a cap defining the axially upstream end of the combustion chamber and oriented about the axis, wherein the cap is configured to receive a fuel injector and at least one glow plug. The torch ignitor includes an elbow connected to the downstream end of the combustion chamber for diverting combustion products along an ignition jet flame axis that is off of the torch axis for injection of combustion products into a gas turbine engine combustor. The torch ignitor further includes a tip at a downstream end of the elbow for issuing the injection of combustion products.

Abstract: An embodiment of a torch ignitor system for a combustor of a gas turbine engine includes a torch ignitor, the torch ignitor include a combustion chamber oriented about a torch axis, the combustion chamber having axially upstream and downstream ends defining a flow direction through the combustion chamber, along the axis. The torch ignitor further includes a tip at a downstream end of the elbow for issuing the injection of combustion products. An embodiment of a method includes initiating combustion in a combustion chamber of a torch ignitor to produce an ignition jet flame extending along an ignition jet flame axis, and igniting a fuel/air mixture in a gas turbine combustor by issuing a respective spray cone of the fuel/air mixture from a respective fuel injectors in a plurality of fuel injectors, wherein the ignition jet flame axis intersects a plurality of the spray cones.

Abstract: A method includes forming fluid conduit inside a heat shield in an additive manufacturing process, removing powder from an interior passage of the fluid conduit and from an insulation gap defined between the fluid conduit and the heat shield, separating the heat shield and fluid conduit from the build platform, and shifting the fluid conduit to a shifted position relative to the heat shield. The method includes securing the fluid conduit to the heat shield in the shifted position.

Abstract: A torch ignitor system for a combustor of a gas turbine engine includes a torch ignitor, the torch ignitor including a combustion chamber oriented about a torch axis, the combustion chamber having axially upstream and downstream ends defining a flow direction through the combustion chamber, along the axis. The torch ignitor includes a cap defining the axially upstream end of the combustion chamber and oriented about the axis, wherein the cap is configured to receive a fuel injector and at least one glow plug. The torch ignitor includes an elbow connected to the downstream end of the combustion chamber for diverting combustion products along an ignition jet flame axis that is off of the torch axis for injection of combustion products into a gas turbine engine combustor. The torch ignitor further includes a tip at a downstream end of the elbow for issuing the injection of combustion products.

Abstract: An embodiment of an ignition system for a gas turbine engine includes a high pressure engine case, a torch ignitor disposed at least partially within the high pressure engine case, the torch ignitor having a combustion chamber oriented about a torch axis, the combustion chamber having axially upstream and downstream ends defining a flow direction through the combustion chamber, along the axis. The ignition system also includes an access hatch configured to allow access through a high pressure engine case to the cap and to seal against the high pressure engine case when not accessing the cap. An embodiment of a method includes removing a hatch from a high pressure engine case to open a hatch opening, performing maintenance on a torch ignitor that is inside the high pressure engine case by accessing the torch ignitor through the hatch opening, replacing the hatch to close the hatch opening after completion of maintenance on the torch ignitor.

Abstract: An embodiment of a torch ignitor system for a combustor of a gas turbine engine includes a torch ignitor, the torch ignitor include a combustion chamber oriented about a torch axis, the combustion chamber having axially upstream and downstream ends defining a flow direction through the combustion chamber, along the axis. The torch ignitor further includes a tip at a downstream end of the elbow for issuing the injection of combustion products. An embodiment of a method includes initiating combustion in a combustion chamber of a torch ignitor to produce an ignition jet flame extending along an ignition jet flame axis, and igniting a fuel/air mixture in a gas turbine combustor by issuing a respective spray cone of the fuel/air mixture from a respective fuel injectors in a plurality of fuel injectors, wherein the ignition jet flame axis intersects a plurality of the spray cones.

Abstract: A fuel injector system includes an outer support and an inner support, with a feed arm extending radially between the inner support and the outer support. A plurality of outlet openings extend in an axial direction from the feed arm for feeding respective injection nozzles. The outer support and feed arm define a plurality of fuel passages therethrough to convey fluid from an external source through the outer support and feed arm to the outlet openings. A heat shield extends around the feed arm from the outer support to the inner support. The heat shield is spaced apart from the feed arm with an insulative gap therebetween.

Abstract: A system includes an engine case. A heat exchanger is included inside the engine case. The heat exchanger includes an air passage and a fuel passage. The air passage and fuel passage are in fluid isolation from one another, but are in thermal communication with one another for exchange of heat.

Abstract: A multipoint fuel injection system comprises an injection system segment including a circumferentially extending outer support defining a fuel manifold with a plurality of manifold passages extending circumferentially therethrough. A first connector is included at a first circumferential end of the outer support and a second connector is included at a second circumferential end of the outer support opposite the first circumferential end. The first and second connectors are each configured to connect each manifold passage with a manifold passages of a respective outer support of a circumferentially adjacent injection system segment. The system includes a circumferentially extending inner support and a plurality of circumferentially spaced apart feed arms extending radially between the inner support and the outer support. A plurality of outlet openings extend in an axial direction from each feed arm for feeding respective injection nozzles.

Abstract: A system includes an internal manifold ring defining at least one circumferentially extending flow channel. A plurality of feed arms extends outward from the manifold ring. A circumferentially segmented outer ring can be supported from the feed arms, outboard of the feed arms. Each feed arm can include a plurality of branches extending therefrom, wherein each branch is in fluid communication with the manifold ring through a respective one of the feed arms. A plurality of nozzles can be included, each nozzle connected to a respective one of the branches, wherein the system is devoid of nozzles radially inward from the manifold ring.

Abstract: A fuel injection system includes an outer support defining a fuel manifold and an inner support, with a feed arm extending radially between the inner support and the outer support. A plurality of outlet openings extending in an axial direction from the feed arm for feeding respective injection nozzles. The feed arm defines a plurality of fuel passages therethrough in fluid communication with the fuel manifold and outlet openings to supply fuel from the fuel manifold to the outlet openings. A heat shield extends from the outer support to the inner support and extends about the outer support and the feed arm to provide heat shielding to the fuel manifold and the fuel passages.

Abstract: An air mixer includes an annular body defining a center axis. A plurality of slots are defined in the annular body circumferentially spaced apart from one another. Each slot defines a respective center injection axis extending from an outer surface of the annular body to an inner surface of the annular body. Each respective center injection axis is parallel to a respective plane bisecting the annular body. At least one of the slots is intersected by the respective bisecting plane parallel to its respective center injection axis.

Abstract: A fuel injector for an exhaust heater includes a cover and an air blast nozzle. The cover has a nozzle seat, a fuel inlet, and an air inlet, the nozzle seat arranged along a flow axis. The air blast nozzle is seated in the nozzle seat and has a unibody. The air blast nozzle unibody is in fluid communication with the fuel inlet and the air inlet arranged along the flow axis to port fuel and air into a combustion volume, e.g., to heat a stream of exhaust gas flowing between an engine and a catalytic reactor by combustion with fuel introduced through the fuel inlet and air introduced through the air inlet.

Abstract: A method includes forming a fluid conduit inside a heat shield in an additive manufacturing process, wherein a fluid nozzle is defined at a downstream end of the fluid conduit, and wherein the heat shield is formed about the fluid nozzle. The method includes removing powder from an interior passage of the fluid conduit and fluid nozzle and from an insulation gap defined between the heat shield and the fluid conduit and fluid nozzle. The method includes separating the heat shield, fluid conduit, and fluid nozzle from the build platform. The method includes shifting the fluid conduit and fluid nozzle to a shifted position relative to the heat shield, and securing the fluid conduit and fluid nozzle to the heat shield in the shifted position.

Abstract: A multipoint fuel injection system comprises an injection system segment including a circumferentially extending outer support defining a fuel manifold with a plurality of manifold passages extending circumferentially therethrough. A first connector is included at a first circumferential end of the outer support and a second connector is included at a second circumferential end of the outer support opposite the first circumferential end. The first and second connectors are each configured to connect each manifold passage with a manifold passages of a respective outer support of a circumferentially adjacent injection system segment. The system includes a circumferentially extending inner support and a plurality of circumferentially spaced apart feed arms extending radially between the inner support and the outer support. A plurality of outlet openings extend in an axial direction from each feed arm for feeding respective injection nozzles.