Abstract: A system includes a gas turbine engine that includes a combustor section having a turbine combustor that generates combustion products, a turbine section having one or more turbine stages driven by the combustion products, an exhaust section disposed downstream of the turbine section, an oxygen sensor adaptor housing disposed in at least one of the combustor section, the turbine section, or the exhaust section, or any combination thereof, and an oxygen sensor disposed in the oxygen sensor adaptor housing. The oxygen sensor adaptor housing is configured to maintain a temperature of a portion of the oxygen sensor below an upper threshold.

Abstract: Certain embodiments herein relate to systems and methods for managing a combustor of a gas turbine engine. In one embodiment, a system can include at least one memory configured to store computer-executable instructions and at least one controller configured to access the at least one memory and execute the computer-executable instructions. The instructions may be configured to monitor the dynamic and static pressures of the combustor by a single sensor. The instructions may be further configured to generate a signal based at least in part on the dynamic and static pressures. Furthermore, the instructions may be configured to facilitate in the execution of at least combustor control event based at least in part on the signal.

Abstract: In a gas turbine engine that includes a compressor and a combustor, wherein the combustor includes a primary fuel injector within a fuel nozzle and a secondary fuel injector that is upstream of the fuel nozzle and configured to inject fuel into a flow annulus of the combustor, a method for detecting a flame holding condition about a fuel injector. The method may include the steps of: detecting an upstream pressure upstream of the secondary fuel injector; detecting a downstream pressure downstream of the secondary fuel injector; determining a measured pressure difference between the upstream pressure and the downstream pressure; and comparing the measured pressure difference to an expected pressure difference.

Abstract: A system includes a gas turbine engine that includes a combustor section having a turbine combustor that generates combustion products, a turbine section having one or more turbine stages driven by the combustion products, an exhaust section disposed downstream of the turbine section, an oxygen sensor adaptor housing disposed in at least one of the combustor section, the turbine section, or the exhaust section, or any combination thereof, and an oxygen sensor disposed in the oxygen sensor adaptor housing. The oxygen sensor adaptor housing is configured to maintain a temperature of a portion of the oxygen sensor below an upper threshold.

Abstract: A system is provided for detecting and controlling flashback and flame holding in a combustor of a gas turbine. The system includes at least one flame indicator disposed in a combustor and at least one detector disposed downstream from the flame indicator. The flame indicator may be configured to produce light when exposed to a flame and the detector may be configured to detect the light produced by the flame indicator.

Abstract: A system is disclosed that includes a combustor having an end cover and at least one fuel nozzle assembly extending from an inner face of the end cover. A cartridge may extend through the end cover and into the fuel nozzle assembly. The cartridge may define an opening for receiving light emitted from within the combustor. Additionally, a fiber optic cable may be disposed within the cartridge and may be configured to capture at least a portion of the light received through the opening.

Abstract: In one embodiment, a system includes at least one sensor configured to communicate a signal representative of a gas turbine operations. The system further includes a controller communicatively coupled to the sensor. The system additionally includes a stoichiometric model configured to receive one or more inputs representative of the gas turbine operations and a measured equivalence ratio, wherein the controller is configured to transform the signal into the one or more inputs and to use the stoichiometric model to derive an actuation signal based on a target equivalence ratio.

Abstract: Optical flame holding and flashback detection systems and methods are provided. Exemplary embodiments include a combustor including a combustor housing defining a combustion chamber having combustion zones, flame detectors disposed on the combustor housing and in optical communication with the combustion chamber, wherein each of the flame detectors is configured to detect an optical property related to one or more of the combustion zones.

Abstract: A turbine to detect a flame holding event includes a combustion section to receive a fluid from a compressor, to heat the fluid by combusting a fuel to generate heat, and to output the heated fluid to a turbine section. The combustion section includes a combustor having a combustion chamber in which the fuel is combusted, and the combustion section having a sensor to sense a static pressure within the combustion chamber. A combustion control device detects a flame holding event in the combustion chamber based only on the sensed static pressure.

Abstract: A method for detecting defects in a combustion duct in a combustion system of a turbine engine while the turbine engine operates, wherein the combustion duct comprises an inner surface, which, during operation, is exposed to the hot-gas flowpath, the method comprising the steps of: providing a first electrode that is electrically connected to the combustion duct; providing a second electrode that resides within the hot-gas flowpath; applying a voltage across the first electrode and the second electrode; and detecting current flowing between the first electrode and the second electrode.

Abstract: Systems and methods for avoidance and correction of potentially adverse combustion states such as flame holding and flashback are disclosed. According to one embodiment of the disclosure, one or more sensors acquire sensor data from one or more sensors associated with combustion. An operational limit margin (OLM) is calculated using an OLM model and based at least in part on the sensor data. A determination is made as to the presence of a potentially adverse combustion state based at least in part on the OLM and the model. Once determined, corrective action may be taken to avoid an adverse combustion event prior to occurrence of the event.

Abstract: A system is provided for detecting and controlling flashback and flame holding in a combustor of a gas turbine. The system includes at least one flame indicator disposed in a combustor and at least one detector disposed downstream from the flame indicator. The flame indicator may be configured to produce light when exposed to a flame and the detector may be configured to detect the light produced by the flame indicator.

Abstract: A nozzle includes a center body that defines an axial centerline. A shroud circumferentially surrounds at least a portion of the center body to define an annular passage between the center body and the shroud. A plenum is inside the center body and substantially parallel to the axial centerline, and an igniter is inside the center body and generally adjacent to the plenum. A method for igniting a combustor includes flowing a fuel through a center body axially aligned in a nozzle and flowing a working fluid through an annular passage, wherein the annular passage is substantially parallel to and radially outward of the center body. The method further includes projecting at least one of a beam, spark, or flame from an igniter located inside the center body.

Abstract: A turbine to detect a flame holding event includes a combustion section to receive a fluid from a compressor, to heat the fluid by combusting a fuel to generate heat, and to output the heated fluid to a turbine section. The combustion section includes a combustor having a combustion chamber in which the fuel is combusted, and the combustion section having a sensor to sense a static pressure within the combustion chamber. A combustion control device detects a flame holding event in the combustion chamber based only on the sensed static pressure.

Abstract: A system for detecting defects in a combustion duct of a combustion system of a combustion turbine engine while the combustion turbine engine operates, wherein the combustion duct comprises a hot side, which is exposed to combustion gases and, opposing the hot side, a cold side. The system may include: an indicator coating disposed on an outer surface of the combustion duct, the indicator coating comprising a detectable substance; and a gas sensor positioned downstream of the combustor, the gas sensor configured to take a measurement of the amount of the detectable substance in the combustion products of the combustion turbine engine.

Abstract: A combustor nozzle includes a center body that defines an axial centerline. A shroud circumferentially surrounds at least a portion of the center body to define an annular passage between the center body and the shroud. A plenum is inside the center body and aligned substantially parallel to the axial centerline. A sensor extends inside the center body and is generally adjacent to the plenum, wherein the sensor detects a condition proximate to the combustor nozzle. A method for monitoring a combustor includes flowing a fuel through a center body axially aligned in a nozzle and flowing a working fluid through an annular passage substantially parallel to and radially outward of the center body. The method further includes sensing a condition inside the combustor using a sensor located inside the center body.

Abstract: In a gas turbine engine that includes a compressor and a combustor, wherein the combustor includes a primary fuel injector within a fuel nozzle and a secondary fuel injector that is upstream of the fuel nozzle and configured to inject fuel into a flow annulus of the combustor, a method for detecting a flame holding condition about a fuel injector. The method may include the steps of: detecting an upstream pressure upstream of the secondary fuel injector; detecting a downstream pressure downstream of the secondary fuel injector; determining a measured pressure difference between the upstream pressure and the downstream pressure; and comparing the measured pressure difference to an expected pressure difference.

Abstract: A method for detecting defects in a combustion duct in a combustion system of a turbine engine while the turbine engine operates, wherein the combustion duct comprises an inner surface, which, during operation, is exposed to the hot-gas flowpath, the method comprising the steps of: providing a first electrode that is electrically connected to the combustion duct; providing a second electrode that resides within the hot-gas flowpath; applying a voltage across the first electrode and the second electrode; and detecting current flowing between the first electrode and the second electrode.

Abstract: A system is disclosed that includes a combustor having an end cover and at least one fuel nozzle assembly extending from an inner face of the end cover. A cartridge may extend through the end cover and into the fuel nozzle assembly. The cartridge may define an opening for receiving light emitted from within the combustor. Additionally, a fiber optic cable may be disposed within the cartridge and may be configured to capture at least a portion of the light received through the opening.

Abstract: A system for detecting defects in a combustion duct of a combustion system of a combustion turbine engine while the combustion turbine engine operates, wherein the combustion duct comprises a hot side, which is exposed to combustion gases and, opposing the hot side, a cold side. The system may include: an indicator coating disposed on the cold side of the combustion duct; and a proximity sensor positioned in proximity to the combustion duct and configured to detect a distance between the position of the proximity sensor and the cold side of the combustion duct.