Abstract: A ducting arrangement (10) in a combustion stage downstream of a main combustion stage of a gas turbine engine is provided. A duct (18) is fluidly coupled to receive a cross-flow of combustion gases from the main combustion stage. Duct (18) includes a duct segment (23) with an expanding cross-sectional area (24) where one or more injector assemblies (26) are disposed. Injector assembly (26) includes one or more reactant-guiding structures (27) arranged to deliver a flow of reactants into the downstream combustion stage to be mixed with the cross-flow of combustion gases. Disclosed injector assemblies are arranged in expanding cross-sectional area (24) to reduce total pressure loss while providing an effective level of mixing of the injected reactants with the passing cross-flow. Respective duct components or the entire ducting arrangement may be formed as a unitized structure, such as a single piece using a rapid manufacturing technology, such as 3D Printing/Additive Manufacturing (AM) technologies.

Abstract: Injector assembly and ducting arrangement including such assemblies for a combustor system in a gas turbine engine are provided. A reactant-guiding structure (42) may be configured to define a curvilinear flow path (47) to route a flow of reactants from a first flow direction (50) to a second flow direction (52) toward a cross-flow of combustion gases (60). A cross-flow guiding structure (54) may further define a flow path (58) to route a portion of the cross-flow of combustion gases toward an outlet side of the cross-flow guiding structure. Disclosed injector assemblies can be configured to reduce pressure loss while providing an effective level of mixing of the injected reactants with the passing cross-flow. Respective injector assemblies or the entire ducting arrangement may be formed as a unitized structure, such as a single piece using a rapid manufacturing technology, such as 3D Printing/Additive Manufacturing (AM) technology.

Abstract: Method and computer-readable model for additively manufacturing an injector assembly or a ducting arrangement including such assembles, as may be used in a combustion system of a gas turbine engine. The injector assembly may include a reactant-guiding structure (42) that may be configured to define a curvilinear flow path (47) to route a flow of reactants from a first flow direction (50) to a second flow direction (52) toward a cross-flow of combustion gases (60). A cross-flow guiding structure (54) may further define a flow path (58) to route a portion of the cross-flow of combustion gases toward an outlet side of the cross-flow guiding structure. Disclosed injector assemblies can be configured to reduce pressure loss while providing an effective level of mixing of the injected reactants with the passing cross-flow.

Abstract: A ducting arrangement (30) in a combustion system of a gas turbine engine is provided. The ducting arrangement may be formed by duct segments (32) circumferentially adjoined with one another to form a flow duct structure (e.g., a flow-accelerating structure (34)) and a pre-mixing structure (35). The flow duct structure is fluidly coupled to pass a cross-flow of combustion gases. The pre-mixing structure (35) may include an array of pre-mixing tubes (48) fluidly coupled to receive air and fuel conveyed by a manifold (42) to inject a mixture of air and fuel into the cross-flow of combustion gases that passes through the flow duct structure. The duct segments or the entire ducting arrangement may be formed as a unitized structure, such as a single piece using a rapid manufacturing technology, such as 3D Printing/Additive Manufacturing (AM) technology.

Abstract: Method and computer-readable model for additively manufacturing a ducting arrangement in a combustion system of a gas turbine engine are provided. The ducting arrangement may be formed by duct segments (32) circumferentially adjoined with one another to form a flow duct structure (e.g., a flow-accelerating structure (34)) and a pre-mixing structure (35). The flow duct structure may be fluidly coupled to pass a cross-flow of combustion gases. The pre-mixing structure (35) may include an array of pre-mixing tubes (48) fluidly coupled to receive air and fuel conveyed by a manifold (42) to inject a mixture of air and fuel into the cross-flow of combustion gases that passes through the flow duct structure. The duct segments or the entire ducting arrangement may be formed as a unitized structure, such as a single piece using a rapid manufacturing technology, such as 3D Printing/Additive Manufacturing (AM) technology.

Abstract: A cooling system (10) for a fuel system in a turbine engine (14) that is usable to cool a fuel nozzle (16) is disclosed. The cooling system (10) may include one or more cooling system housings (18) positioned around the fuel nozzle (16), such that the cooling system housing (18) forms a cooling chamber (20) defined at least partially by an inner surface (22) of the cooling system housing (18) and an outer surface (24) of the fuel nozzle (16). The fuel nozzle (16) may extend into a combustor chamber (26) formed at least in part by a combustor housing (32). The fuel nozzle (16) may include one or more fuel exhaust orifices (28) with an opening (30) in an outer surface (24) of the fuel nozzle (16) and configured to exhaust fluids unrestricted by the housing (18) forming the cooling system cooling chamber (20). The cooling system (10) may provide cooling fluids to cool the fuel nozzle (16) within the cooling system cooling chamber (20) regardless of whether the fuel nozzle (16) is in use.

Abstract: A method of operating an axial stage combustion system in a gas turbine engine (12) including an EGR system (14) that extracts a portion of exhaust gas produced by the gas turbine engine (12) to a second axial stage of a combustor (18). The extracted exhaust gas is provided at an elevated temperature to a group of injector nozzles (50) at the second axial stage (34) of the combustor (18). A secondary fuel supply line (34) extends to an inlet on each of the injector nozzles (50), and the fuel is mixed with the exhaust gas within the injector nozzles (50) and the mixture of fuel and exhaust gas is injected into the second axial stage (34) of the combustor (18).

Abstract: A flow conditioning device for a can annular gas turbine engine, including a plurality of flow elements disposed in a compressed air flow path leading to a combustor, configured such that relative adjustment of at least one flow directing element with respect to an adjacent flow directing element during operation of the gas turbine engine is effective to adjust a level of choking of the compressed air flow path.

Abstract: A gas turbine combustor (23) includes a catalytic combustion stage (22) receiving a first portion (18) of a total oxidizer flow (16) and a first portion (30) of a total fuel flow (29) and discharging a partially oxidized fuel/oxidizer mixture (40) into a post catalytic combustion stage (24) defined by a combustion liner (58). The combustor further includes an injector scoop (54) having an injector scoop inlet (56) in fluid communication with an opening (56) in the combustion liner for receiving a second portion (20) of the oxidizer flow. A fuel outlet (e.g. 64) selectively supplies a second portion (42) of the total fuel flow into the second portion of the oxidizer flow.

Abstract: A gas turbine includes a compressor, a combustor, a turbine, and a flow path diverting an excess portion of the compressed air produced by the compressor around the turbine. The flow path conducts the excess portion into a turbine exhaust gas flow producing a cooled exhaust gas. A method of operating the gas turbine includes opening an inlet guide vane of the compressor to allow the compressor to produce an increased volume of compressed air. The increased volume exceeds a volume of compressed air needed to support combustion. An excess portion of the compressed air is directed into the exhaust gas to produce a cooled exhaust. In a combined cycle power plant, the cooled exhaust from the gas turbine may be used to warm a steam turbine portion to a desired temperature while allowing operation of the gas turbine at a power level that produces exhaust gas at a temperature higher than the desired temperature.

Abstract: A catalytic gas turbine includes a compressor, a catalytic combustor, a turbine, and a flow path conducting a bypass portion of the compressed air around the combustor and turbine. A method of operating the catalytic gas turbine to activate a catalyst in the catalytic combustor includes opening an inlet guide vane upstream of the compressor to a position to produce an increased volume of compressed air. The increased volume exceeds a volume of compressed air needed to support combustion. A bypass portion of the compressed air is extracted and directed around the combustor and turbine. The method may also include extracting a recirculation portion of the compressed air and directing the recirculation portion into the inlet of the compressor.

Abstract: A pilotless catalytic combustor (10) including a basket (12) having a central axis (14) and a central core region (16) disposed along a portion of the central axis. Catalytic combustion modules (18) are circumferentially disposed about the central axis radially outward of the central core region for receiving a fuel flow (20) and a first portion of an oxidizer flow (22), and discharge a partially oxidized fuel/oxidizer mixture (24) at respective exit ends (26). A base plate (30) is positioned in the central core region upstream of the exit ends of the catalytic combustion modules, the baseplate defining a recirculation zone (32) near the respective exit ends for stabilizing oxidation in the burnout zone. A method of staged fueling for a pilotless catalytic combustor includes providing fuel to at least one of the modules during start up and progressively providing fuel to other modules as a load on the turbine engine is increased.