Abstract: A computer-implemented method for multi-mode operation of a combustion system, a combustion system, and a heat engine are provided. The method includes initializing combustion of a fuel/oxidizer mixture, determining whether conditions at the combustion system meet or exceed a first threshold operating parameter, transitioning to detonation combustion of the fuel/oxidizer mixture if conditions at the combustion system meet or exceed the first threshold operating parameter, and maintaining or increasing fuel flow through a deflagrative fuel circuit if conditions at the combustion system do not meet or exceed the first threshold operating parameter.

Abstract: A rotating detonation combustion (RDC) system is provided. The RDC includes a first outer wall and a second outer wall each extended around a centerline axis, and a detonation chamber formed radially inward of the second outer wall. A fuel passage extended between the first outer wall and the second outer wall, the fuel passage including a first inlet opening proximate to the aft end through which a flow of fuel is received into the fuel passage. The flow of fuel is provided through the fuel passage from the aft end to the forward end of the RDC system and to the detonation chamber.

Abstract: A rotating detonation combustion (RDC) system is provided. The RDC includes a first outer wall and a second outer wall each extended around a centerline axis, and a detonation chamber formed radially inward of the second outer wall. A fuel passage extended between the first outer wall and the second outer wall, the fuel passage including a first inlet opening proximate to the aft end through which a flow of fuel is received into the fuel passage. The flow of fuel is provided through the fuel passage from the aft end to the forward end of the RDC system and to the detonation chamber.

Abstract: A computer-implemented method for multi-mode operation of a combustion system, a combustion system, and a heat engine are provided. The method includes initializing combustion of a fuel/oxidizer mixture, determining whether conditions at the combustion system meet or exceed a first threshold operating parameter, transitioning to detonation combustion of the fuel/oxidizer mixture if conditions at the combustion system meet or exceed the first threshold operating parameter, and maintaining or increasing fuel flow through a deflagrative fuel circuit if conditions at the combustion system do not meet or exceed the first threshold operating parameter.

Abstract: Systems for rotating detonation combustion are provided herein. The system includes an inner wall and an outer wall each extended around a centerline axis, wherein a detonation chamber is defined between the inner wall and the outer wall, and an iterative structure positioned at one or both of the inner wall or the outer wall. The iterative structure includes a first threshold structure corresponding to a first pressure wave attenuation and a second threshold structure corresponding to a second pressure wave attenuation. The iterative structure provides for pressure wave strengthening along a first circumferential direction in the detonation chamber or pressure wave weakening along a second circumferential direction opposite of the first circumferential direction. The first circumferential direction corresponds to a desired direction of pressure wave propagation in the detonation chamber.

Abstract: A micromixer of a gas turbine has a plurality of tubes each having an inlet and an outlet for receiving a flow and dispersing the flow to a combustor. At least some of the tubes have a liquid fuel injector, and the liquid fuel injector projects into one of the tubes. The liquid fuel injector has a ramped upstream surface and two converging side surfaces. The ramped upstream surface compresses the flow passing thereover, and a top surface of the liquid fuel injector comprises a liquid fuel outlet.

Abstract: A rotating detonation combustor includes an annular combustion passage that is non-circular. Specifically, the present rotating detonation combustor includes a forward wall, a radially inner wall, and a radially outer wall. The radially inner wall and the radially outer wall extend downstream from the forward wall around a longitudinal axis of the combustor, thus defining an annular passage between the radially inner wall and the radially outer wall. An air inlet and a fuel inlet are disposed proximate to the forward wall and in fluid communication with the annular passage. The cross-section of the annular passage, which can be elliptical or polygonal, is defined by arcuate and/or straight sides of the inner and outer walls.

Abstract: A micromixer of a gas turbine has a plurality of tubes each having an inlet and an outlet for receiving a flow and dispersing the flow to a combustor. At least some of the tubes have a liquid fuel injector, and the liquid fuel injector projects into one of the tubes. The liquid fuel injector has a ramped upstream surface and two converging side surfaces. The ramped upstream surface compresses the flow passing thereover, and a top surface of the liquid fuel injector comprises a liquid fuel outlet.

Abstract: A liquid fuel injection assembly for a gas turbine engine is provided. The liquid fuel injection assembly includes at least one micromixer, at least one liquid fuel injection nozzle, and at least one post. The at least one micromixer includes at least one wall defining a conduit. The at least one liquid fuel injection nozzle extends from the at least one wall into the conduit. The at least one liquid fuel injection nozzle has a first drag coefficient. The at least one liquid fuel injection nozzle is configured to inject a flow of liquid fuel into the flow of air. The at least one post extends from the at least one wall and circumscribes the at least one liquid fuel injection nozzle. The liquid fuel injection nozzle and post have a second drag coefficient. The first drag coefficient is greater than the second drag coefficient.

Abstract: A fuel injector to reduce NOx emissions in a combustor system. The fuel injector including a housing, at least one oxidizer flow path, extending axially through the fuel injector housing and defining therein one or more oxidizer flow paths for an oxidizer stream and a fuel manifold, extending axially through the fuel injector housing and defining therein one or more fuel flow path. The fuel manifold includes a forward portion and an aft portion including an aft face. A plurality of fuel injector outlets are defined in the aft portion, wherein the plurality of fuel injector outlets are configured to inject a fuel flow along a mid-plane of the fuel injector and away from a downstream wall. The fuel flow exiting the fuel manifold undergoes circumferential and radial mixing upon interaction with the oxidizer stream. Additionally disclosed is a combustor system including the fuel injector.

Abstract: An air-shielded fuel injection assembly for use in a combustion chamber of a turbine assembly. The air-shielded fuel injection assembly generally includes a fuel manifold including a plurality of fuel injection ports and an air manifold including a plurality of air injection ports. Each of the plurality of fuel injection ports is configured to introduce a fuel column into an annular cavity of a mixer assembly. Each of the plurality of air injection ports is configured to introduce an air curtain about an associated fuel injection column to minimize recirculation upstream of the fuel injection column and increase penetration of the fuel injection column into the cavity. Also disclosed are a mixer assembly and a turbine assembly including the air-shielded fuel injection assembly.

Abstract: A turbine assembly is provided. The turbine assembly includes a gas turbine engine including at least one hot gas path component formed at least partially from a ceramic matrix composite material. The turbine assembly also includes a treatment system positioned to receive a flow of exhaust gas from the gas turbine engine. The treatment system is configured to remove water from the flow of exhaust gas to form a flow of treated exhaust gas, and to channel the flow of treated exhaust gas towards the at least one hot gas path component. The at least one hot gas path component includes a plurality of cooling holes for channeling the flow of treated exhaust gas therethrough, such that a protective film is formed over the at least one hot gas path component.

Abstract: An air-shielded fuel injection assembly for use in a combustion chamber of a turbine assembly. The air-shielded fuel injection assembly generally includes a fuel manifold including a plurality of fuel injection ports and an air manifold including a plurality of air injection ports. Each of the plurality of fuel injection ports is configured to introduce a fuel column into an annular cavity of a mixer assembly. Each of the plurality of air injection ports is configured to introduce an air curtain about an associated fuel injection column to minimize recirculation upstream of the fuel injection column and increase penetration of the fuel injection column into the cavity. Also disclosed are a mixer assembly and a turbine assembly including the air-shielded fuel injection assembly.

Abstract: A turbine engine assembly including a rotating detonation combustor configured to combust a fuel-air mixture formed at least partially from a primary fuel including methane. The assembly also includes a fuel reformer configured to produce a secondary fuel, wherein the fuel reformer is further configured to channel a flow of secondary fuel towards the rotating detonation combustor such that the fuel-air mixture further includes the secondary fuel.

Abstract: A fuel nozzle system for enabling a gas turbine to start and operate on low-Btu fuel includes a primary tip having primary fuel orifices and a primary fuel passage in fluid communication with the primary fuel orifices, and a fuel circuit capable of controlling flow rates of a first and second low-Btu fuel gases flowing into the fuel nozzle. The system is capable of operating at an ignition status, in which at least the first low-Btu fuel gas is fed to the primary fuel orifices and ignited to start the gas turbine, and a baseload status, in which at least the second low-Btu fuel gas is fired at baseload. The low-Btu fuel gas ignited at the ignition status has a content of the first low-Btu fuel gas higher than that of the low-Btu fuel gas fired at the baseload status. Methods for using the system are also provided.

Abstract: A turbine assembly is provided. The turbine assembly includes a gas turbine engine including at least one hot gas path component formed at least partially from a ceramic matrix composite material. The turbine assembly also includes a treatment system positioned to receive a flow of exhaust gas from the gas turbine engine. The treatment system is configured to remove water from the flow of exhaust gas to form a flow of treated exhaust gas, and to channel the flow of treated exhaust gas towards the at least one hot gas path component. The at least one hot gas path component includes a plurality of cooling holes for channeling the flow of treated exhaust gas therethrough, such that a protective film is formed over the at least one hot gas path component.

Abstract: A turbine system and method of operating is provided. The system includes a compressor configured to generate a compressed low-oxygen air stream and a combustor configured to receive the compressed low-oxygen air stream and to combust a fuel stream to generate a post combustion gas stream. The turbine system also includes a turbine for receiving the post combustion gas stream to generate a low-NOx exhaust gas stream, a heat recovery system configured to receive the low-NOx exhaust gas stream and generate a cooled air stream and an auxiliary compressor configured to generate an oxygen and water vapor deficient cooled and compressed air stream. A portion of the oxygen and water vapor deficient cooled and compressed air stream is directed to the combustor to generate an Oxygen and H2O deficient film on exposed portions of the combustor, and another portion is directed to the turbine to provide a cooling flow.

Abstract: A nozzle for assemblies and gas turbines is provided. The nozzle exhibits destabilized flame holding characteristics, i.e., the nozzle is unable to stabilize flame up to an equivalence ratio of about 0.65. As a result, flame heat release is delayed resulting in lower peak flame temperatures and correspondingly lower NOx levels. Flame stabilization capability is retained for higher equivalence ratios to support operation of the combustor in other regions of the load range.

Abstract: A gas turbine engine system includes a compressor, a combustor, and a turbine. The combustor is coupled to the compressor and disposed downstream of the compressor. The combustor includes a secondary combustor section coupled to a primary combustor section and disposed downstream of the primary combustor section. The combustor also includes a transition nozzle coupled to the secondary combustor section and disposed downstream of the secondary combustor section. The combustor further includes an injector coupled to the secondary combustor section, for injecting an air-fuel mixture to the secondary combustor section. The turbine is coupled to the combustor and disposed downstream of the transition nozzle; wherein the transition nozzle is oriented substantially tangential to the turbine.

Abstract: An air-shielded fuel injection assembly for use in a combustion chamber of a turbine assembly. The air-shielded fuel injection assembly generally includes a fuel manifold including a plurality of fuel injection ports and an air manifold including a plurality of air injection ports. Each of the plurality of fuel injection ports is configured to introduce a fuel column into an annular cavity of a mixer assembly. Each of the plurality of air injection ports is configured to introduce an air curtain about an associated fuel injection column to minimize recirculation upstream of the fuel injection column and increase penetration of the fuel injection column into the cavity. Also disclosed are a mixer assembly and a turbine assembly including the air-shielded fuel injection assembly.