Patent Application
20150338101
The subject matter disclosed herein relates to the art of turbomachines and, more particularly, to a turbomachine combustor including a combustor sleeve baffle.
Turbomachines include a compressor portion linked to a turbine portion through a common compressor/turbine shaft and a combustor assembly. An inlet airflow is passed through an air intake toward the compressor portion. In the compressor portion, the inlet airflow is compressed through a number of sequential stages toward the combustor assembly. In the combustor assembly, the compressed airflow mixes with a fuel to form a combustible mixture. The combustible mixture is combusted in the combustor assembly to form hot gases. The hot gases are guided along a hot gas path of the turbine portion through a transition piece. The hot gases expand along a hot gas path through a number of turbine stages acting upon turbine bucket airfoils mounted on wheels to create work that is output, for example, to power a generator. A portion of the compressed air is passed through various components of the turbomachine for cooling purposes. In some case, air for cooling is passed through a combustor sleeve that surrounds the combustor. The air for cooling may enter the combustor as part of the combustible mixture.
According to an aspect of an exemplary embodiment, a turbomachine combustor includes a combustor body extending from a head end to a discharge end. The combustor body includes a combustor liner defining a combustion chamber. A combustor sleeve surrounds the combustor liner. The combustor sleeve is spaced from the combustor liner forming a passage. The combustor sleeve includes at least one opening. A baffle is arranged in the passage. The baffle includes a curvilinear surface extending from the combustor sleeve across the at least one opening toward the head end of the combustor body. The baffle is configured and disposed to compress a fluid flow passing through the passage toward the head end.
According to another aspect of an exemplary embodiment, a turbomachine includes a compressor portion, a turbine portion operatively connected to the compressor portion, and a combustor assembly fluidically connected to the compressor portion and the turbine portion. The combustor assembly includes at least one combustor having a combustor body extending from a head end to a discharge end. The combustor body includes a combustor liner defining a combustion chamber. A combustor sleeve surrounds the combustor liner. The combustor sleeve is spaced from the combustor liner forming a passage. The combustor sleeve includes at least one opening. A baffle is arranged in the passage. The baffle includes a curvilinear surface extending from the combustor sleeve across the at least one opening toward the head end of the combustor body. The baffle is configured and disposed to compress a fluid flow passing through the passage toward the head end.
According to yet another aspect of an exemplary embodiment, a method of passing air through a combustor includes a passage defined between a combustor liner and a combustor sleeve including guiding a first airflow through the passage toward a head end of the combustor, passing the first airflow over a baffle, compressing the first airflow between the baffle and the combustor liner, introducing a second airflow into the first airflow downstream of the baffle, and merging the first airflow and the second airflow creating a substantially turbulent free airflow.
These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.
The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
With reference to
Air enters air inlet system 24 and flows to compressor portion 4. The air is compressed and passed to combustor assembly 10. A portion of the air is passed into turbine portion 6 for cooling. In combustor assembly 10 the air is mixed with a fuel and or diluents to form a combustible mixture. The combustible mixture is combusted forming hot gases that pass from combustor assembly 10 to turbine portion 6. The hot gases expand through turbine portion 6 which converts thermal energy from the hot gases into mechanical energy that drives driven component 20. The hot gases pass from turbine portion 6 to an exhaust system (not shown).
As best shown in
In accordance with an exemplary embodiment, combustor 14 includes a baffle 80 arranged in passage 64. Baffle 80 is arranged downstream from any obstacles that may be present in passage 64. With this arrangement, air passing over baffle 80 has a substantially unobstructed flow path to head end 36. As shown in
The reduction of turbulence in passage 64 resulting from compressing the air between combustion liner 50 and curvilinear surface 86 also improves heat transfer from a hot side of the combustion liner 50 to air passing over the combustion liner 50 thereby prolonging an overall service life and reliability of combustor assembly 10. Performance improvements may also be realized by a reduction in pressure losses and by a reduction of NOx emissions. More specifically, improving uniformity will lead to each nozzle 46 receiving a substantially identical (by volume) air flow and thus create a more uniform air/flow mixture for combustion. Uniformity of the air/fuel mixtures leads to more complete combustion and improved flameholding resulting in a reduction in emissions such as NOx.
In accordance with an aspect of an exemplary embodiment illustrated in
At this point it should be understood that the exemplary embodiments describe a baffle arranged in an annular passage of a reverse flow combustor. The baffle conditions a turbulent airflow passing along the combustor toward the head end. More specifically, the baffle compresses the airflow against the combustor liner to reduce air recirculation leading to enhanced flow uniformity. In this manner, the exemplary embodiments reduce impingement pressure losses for air coming through openings in the baffle to enhance combustion properties of the combustor. It should also be understood that baffle 80 may include a divergent portion 160 that may further enhance flow uniformity in passage 64, as shown in
While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
