FIELD

The present disclosure relates generally to an integrated combustion nozzle for a gas turbine engine. More specifically, this disclosure relates to a compact integrated combustion nozzle having a unified two stage combustion system.

BACKGROUND

Turbomachines are utilized in a variety of industries and applications for energy transfer purposes. For example, a gas turbine engine generally includes a compressor section, a combustion section, a turbine section, and an exhaust section. The compressor section progressively increases the pressure of a working fluid entering the gas turbine engine and supplies this compressed working fluid to the combustion section. The compressed working fluid and a fuel (e.g., natural gas) mix within the combustion section and burn in a combustion chamber to generate high pressure and high temperature combustion gases. The combustion gases flow from the combustion section into the turbine section where they expand to produce work. For example, expansion of the combustion gases in the turbine section may rotate a rotor shaft connected, e.g., to a generator to produce electricity. The combustion gases then exit the gas turbine via the exhaust section.

Turbomachine combustion systems usually burn hydrocarbon fuels and produce air polluting emissions such as oxides of nitrogen (NOx) and carbon monoxide (CO). Oxidization of molecular nitrogen in the turbomachine depends upon the temperature of gas located in a combustor, as well as the residence time for reactants located in the highest temperature regions within the combustor. Thus, the amount of NOx produced by the turbomachine may be reduced or controlled by either maintaining the combustor temperature below a temperature at which NOx is produced, or by limiting the residence time of the reactant in the combustor.

One approach for controlling the temperature of the combustor involves pre-mixing fuel and air to create a fuel-air mixture prior to combustion. This approach may include the axial staging of fuel injectors where a first fuel-air mixture is injected and ignited at a first or primary combustion zone of the combustor to produce a main flow of high energy combustion gases, and where a second fuel-air mixture is injected into and mixed with the main flow of high energy combustion gases via a plurality of radially oriented and circumferentially spaced fuel injectors or axially staged fuel injector assemblies positioned downstream from the primary combustion zone. The injection of the second fuel-air mixture into the secondary combustion zone is sometimes referred to as a “jet-in-crossflow” arrangement.

Axially staged injection increases the likelihood of complete combustion of available fuel, which in turn reduces the air polluting emissions. However, with conventional axially staged fuel injection combustion systems, there are multiple components having complex geometries that are difficult and time consuming to assemble. Thus, scaling the axially staged combustors, e.g., from a large combustor to a small combustor, can be difficult due to the room required for the assembly. Therefore, an improved gas turbine combustion system which includes axially staged fuel injection and is capable of being fully scaled would be useful in the industry.

BRIEF DESCRIPTION

Aspects and advantages of the integrated combustion nozzles and turbomachines in accordance with the present disclosure will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the technology.

In accordance with one embodiment, an integrated combustion nozzle is provided. The integrated combustion nozzle includes a combustion liner that extends along a radial direction between an inner liner segment and an outer liner segment. The combustion liner includes a forward end portion axially separated from an aft end portion. The combustion liner further includes a first side wall and a second side wall. The aft end portion of the combustion liner defines a turbine nozzle. The first side wall and the second side wall each define an opening that extends both axially and radially. The integrated combustion nozzle further includes a unified head end coupled to the combustion liner. The unified head end is in fluid communication with a fuel supply. The unified head end includes a first fuel nozzle and a second fuel nozzle disposed at the forward end portion of the combustion liner. A fuel plenum is defined between the first fuel nozzle and the second fuel nozzle. A first liner portion extends from the first fuel nozzle and into the opening of the first wall such that the first liner portion forms a continuous surface with the first wall of the combustion liner. The unified head end further includes a second liner portion that extends from the second fuel nozzle and into the opening of the second wall such that the second liner portion forms a continuous surface with the second wall of the combustion liner.

In accordance with another embodiment, a turbomachine is provided. The turbomachine includes a compressor section and a compressor discharge casing disposed downstream from the compressor section. A turbine section is disposed downstream from the compressor discharge casing. The turbomachine further includes an annular combustion system disposed within the compressor discharge casing. The annular combustion system includes a plurality of integrated combustion nozzles disposed in an annular array about an axial centerline of the turbomachine. Each integrated combustion nozzle includes a combustion liner extending along a radial direction between an inner liner segment and an outer liner segment. The combustion liner includes a forward end portion axially separated from an aft end portion. The combustion liner further includes a first side wall and a second side wall. The aft end portion of the combustion liner defines a turbine nozzle. The first side wall and the second side wall each define an opening that extends both axially and radially. The integrated combustion nozzle further includes a unified head end coupled to the combustion liner. The unified head end is in fluid communication with a fuel supply. The unified head end includes a first fuel nozzle and a second fuel nozzle disposed at the forward end portion of the combustion liner. A fuel plenum is defined between the first fuel nozzle and the second fuel nozzle. A first liner portion extends from the first fuel nozzle and into the opening of the first wall such that the first liner portion forms a continuous surface with the first wall of the combustion liner. The unified head end further includes a second liner portion that extends from the second fuel nozzle and into the opening of the second wall such that the second liner portion forms a continuous surface with the second wall of the combustion liner.

These and other features, aspects and advantages of the present integrated combustion nozzles and turbomachines will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the technology and, together with the description, serve to explain the principles of the technology.

