Abstract:
In operating a gas turbine, there can be a difference between the desired heating value of the fuel and the actual needs of the fuel for sustainable combustion during various stages of the turbine operation. In one aspect, combustible lean limit operation of the gas turbine free of lean blow out is enabled by adjusting fuel-air-ratio of the fuel and fuel-air mixture properties, based on the operation requirements of the turbine and flammability of the fuel components.
Abstract:
A method and system for preventing or reducing the risk of combustion instabilities in a gas turbine includes utilizing a turbine controller computer processor to compare predetermined and stored stable combustion characteristics, including rate of change of the characteristics, with actual operating combustion characteristics. If the actual operating combustion characteristics are divergent from stable combustion characteristics then the controller modifies one or more gas turbine operating parameters which most rapidly stabilize the operation of the gas turbine.
Abstract:
Certain embodiments of the invention may include systems and methods for compensating fuel composition variations in a gas turbine. According to an example embodiment of the invention, a method is provided for compensating for fuel composition variations in a turbine. The method can include: monitoring at least one fuel parameter associated with a turbine combustor; monitoring one or more combustion dynamics characteristics associated with the turbine combustor; monitoring one or more performance and emissions characteristics associated with the turbine; estimating fuel composition based at least in part on the at least one fuel parameter, the one or more combustion dynamics characteristics, and the one or more performance and emissions characteristics, and adjusting at least one fuel parameter based at least in part on the estimated fuel composition.
Abstract:
A fuel nozzle and a method for operating a combustor are disclosed. The method includes flowing a fuel and an oxidizer through a fuel nozzle, the fuel nozzle comprising an inner tube, an intermediate tube, and an outer tube each configured for flowing one of the fuel or the oxidizer therethrough. At least one of the inner tube, the intermediate tube, or the outer tube includes a plurality of swirler vanes. The method further includes imparting a swirl to the fuel and the oxidizer in the fuel nozzle, and exhausting the fuel and the oxidizer from the fuel nozzle into a combustion zone.
Abstract:
A combustor nozzle includes a fuel passage that extends generally axially in the nozzle and a surface that extends radially across at least a portion of the fuel passage. A projection in the surface extends generally axially down-stream from the surface, and an indention in the surface radially surrounds the projection. An oxidant supply is in fluid communication with an oxidant passage, and the oxidant passage is radially displaced from the fuel passage and terminates at an oxidant outlet. A method of supplying a fuel to a combustor includes flowing fuel through a projection in a surface, wherein the projection extends generally axially downstream from the surface, and flowing fuel through an indention in the surface, wherein the indention radially surrounds the projection. The method further includes flowing an oxidant through an oxidant outlet that circumferentially surrounds the indention in the surface.
Abstract:
The present application thus provides a fuel nozzle for use with one or more flows of fuel and a flow of air in a combustor. The fuel nozzle may include one or more gas fuel passages for the one or more of flows of fuel, a swirler with one or more air chambers therein surrounding the gas fuel passages, and a collar with one or more curtain slots surrounding the swirler. The flow of air is divided between a swirler flow through the air chambers and a curtain flow through the curtain slots.
Abstract:
A system including a controller. The controller may receive a signal indicative of an emissions level of a turbine. The controller may also generate at least one control signal. This control signal may control a split of diluent between a first and a second mixing chamber, whereby the first and the second mixing chambers are located in a fuel nozzle in the turbine.
Abstract:
A combustor includes an end cover having a nozzle. The nozzle has a front end face and a central axis. The nozzle includes a plurality of fuel passages and a plurality of oxidizer passages. The fuel passages are configured for fuel exiting the fuel passage. The fuel passages are positioned to direct fuel in a first direction, where the first direction is angled inwardly towards the center axis. The oxidizer passages are configured for having oxidizer exit the oxidizer passages. The oxidizer passages are positioned to direct oxidizer in a second direction, where the second direction is angled outwardly away from the center axis. The plurality of fuel passages and the plurality of oxidizer passages are positioned in relation to one another such that fuel is in a cross-flow arrangement with oxidizer to create a burning zone in the combustor.
Abstract:
A secondary fuel nozzle for a turbine includes a passive purge air passageway which provides purge air to the secondary nozzle at all times that the nozzle is in operation. The passive purge air passageway draws in air from a location adjacent an upstream end of the nozzle. Because of a pressure differential between air located at the downstream end of the nozzle and air located at the upstream end of the nozzle, purge air will run through the passive purge air passageway at all times the nozzle is in operation. There is no need for a supply of compressed purge air.
Abstract:
A fuel nozzle and a method for operating a combustor are disclosed. The method includes flowing a fuel and an oxidizer through a fuel nozzle, the fuel nozzle comprising an inner tube, an intermediate tube, and an outer tube each configured for flowing one of the fuel or the oxidizer therethrough. At least one of the inner tube, the intermediate tube, or the outer tube includes a plurality of swirler vanes. The method further includes imparting a swirl to the fuel and the oxidizer in the fuel nozzle, and exhausting the fuel and the oxidizer from the fuel nozzle into a combustion zone.