Patent Application
20160102580
The present disclosure relates to a gas turbine engine and, more particularly, to a power turbine section therefor.
In a gas turbine engine, such as a large frame heavy-duty industrial gas turbine (IGT) engine, a core gas stream generated in a gas generator section is passed through a power turbine section to produce mechanical work. The power turbine includes one or more rows, or stages, of stator vanes and rotor blades that react with the core gas stream.
Interaction of the core gas stream with the power turbine hardware may result in the hardware being subjected to temperatures beyond the design points. Over time, such temperatures may reduce the life of the power turbine at the junction between the gas generator section and the power turbine section.
A power turbine section for a gas turbine engine according to one disclosed non-limiting embodiment of the present disclosure includes a first power turbine vane array; and an inlet duct upstream of said first power turbine vane array, said inlet duct including an annular inner duct wall spaced from an annular outer duct wall, said annular inner duct wall including a lip.
A further embodiment of the present disclosure includes, wherein said lip extends from a gas path surface of said annular inner duct wall.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said lip defines a ramp.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said ramp defines an angle of about ten (10) degrees with respect to a gas path surface.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said lip is defines a downstream edge of said annular inner duct wall.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said downstream edge of said annular inner duct wall at least partially axially overlaps a mount lug of said first power turbine vane array, said mount lug receivable into a bearing support.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said inlet duct generally forms a frustoconical shape.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein an upstream edge of said annular inner duct wall and said annular outer duct wall are radially inboard of a respective downstream edge of said annular inner duct wall and said annular outer duct wall.
A further embodiment of any of the foregoing embodiments of the present disclosure includes an inlet case that supports said first power turbine vane array and said inlet duct upstream.
A further embodiment of any of the foregoing embodiments of the present disclosure includes an air strut that extends through said inlet case and said inlet duct.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said air strut extends through said inlet duct aft of an upstream edge and forward of a downstream edge of said inlet duct.
A gas turbine engine according to another disclosed non-limiting embodiment of the present disclosure includes a gas generator section and a power turbine section driven by said gas generator section, said power turbine section including an inlet duct, said inlet duct including an annular inner duct wall spaced from an annular outer duct wall, said annular inner duct wall including a lip.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, a first power turbine vane array, said inlet duct upstream of said first power turbine vane array.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said lip extends from a gas path surface of said annular inner duct wall.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said lip defines a ramp.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said ramp defines an angle of about ten (10) degrees with respect to said gas path surface.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said lip defines a downstream edge of said annular inner duct wall
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said downstream edge of said annular inner duct wall at least partially axially overlaps a mount lug of a first power turbine vane array, said mount lug receivable into a bearing support.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said bearing support is a #7 bearing support.
A further embodiment of any of the foregoing embodiments of the present disclosure includes, wherein said gas turbine engine is an industrial gas turbine engine within a ground mounted enclosure.
The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be exemplary in nature and non-limiting.
Various features will become apparent to those skilled in the art from the following detailed description of the disclosed non-limiting embodiment. The drawings that accompany the detailed description can be briefly described as follows:
The compressor section 24, the combustor section 26, and the turbine section 28 is commonly referred to as the gas generator section to drive the power turbine section 30. The power turbine section 30 drives an output shaft 34 to power a generator 36 or other system. The power turbine section 30 generally includes a power turbine inlet 50 (
With reference to
With reference to
The respective inner vane platform 72 and the outer vane platform 74 at least partially bound a core gas path flow C along a core gas path 62 inclusive of the airfoils 70. The air strut 56 communicates a secondary cooling airflow “S” from, for example, the compressor section 24 to cool hardware in the rotor and bearing compartment of the power turbine section 30. In this disclosed non-limiting embodiment, the secondary cooling airflow
“S” flows through the annular inner duct wall 80, then through the bearing support 58. It should be appreciated that various apertures, and metering features may be provided within the annular inner duct wall 80 and/or the bearing support 58 to control the secondary cooling airflow “S”.
The inlet duct 54 generally includes an annular inner duct wall 80 and an annular outer duct wall 82. The annular inner duct wall 80 includes an upstream edge 84 (
The air strut 56 extends through the inlet duct 54 aft of the upstream edges 84, 92 and fore of the downstream edges 86, 94. It should be appreciated that “fore” and “aft” as described herein are with respect with the core airflow C through the engine 20 from the compressor section 24 to the exhaust section 32. The downstream edges 86, 94 are upstream of the respective inner vane platform 72 and the outer vane platform 74. The annular inner duct wall 80 and the annular outer duct wall 82 are spaced to generally correspond with the span of the airfoils 70.
With reference to
The lip 100 facilitates direction of the core gas stream with respect to the inner vane platform 72 to minimize the entry of the core gas path flow C into an inner cavity 104 to minimize the thermal stresses otherwise applied to the bearing support 58 as compared to a conventional edge (RELATED ART;
The lip 100 of the downstream edge 86 of the annular inner duct wall 80 also extends toward the respective inner vane platform 72 to at least partially axially overlap a mount lug 110 of the first power turbine vane array 60 that is received into the bearing support 58. The lip 100 thereby further minimizes ingestion of the core gas path flow C as compared to the conventional edge (RELATED ART;
The use of the terms “a,” “an,” “the,” and similar references in the context of description (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or specifically contradicted by context. The modifier “about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the particular quantity). All ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other. It should be appreciated that relative positional terms such as “forward,” “aft,” “upper,” “lower,” “above,” “below,” and the like are with reference to the normal operational attitude and should not be considered otherwise limiting.
Although the different non-limiting embodiments have specific illustrated components, the embodiments of this invention are not limited to those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments.
It should be appreciated that like reference numerals identify corresponding or similar elements throughout the several drawings. It should also be appreciated that although a particular component arrangement is disclosed in the illustrated embodiment, other arrangements will benefit herefrom.
Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated and will still benefit from the present disclosure.
The foregoing description is exemplary rather than defined by the limitations within. Various non-limiting embodiments are disclosed herein, however, one of ordinary skill in the art would recognize that various modifications and variations in light of the above teachings will fall within the scope of the appended claims. It is therefore to be appreciated that within the scope of the appended claims, the disclosure may be practiced other than as specifically described. For that reason the appended claims should be studied to determine true scope and content.
