Patent Description:
Turbomachines (such as a land-based power generating gas turbine) 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.

Generally, the compressor section includes a compressor casing, a plurality of stator vanes mounted to the compressor casing, and a plurality of rotor blades mounted to a rotor of the turbomachine. The compressor casing is a stationary component that includes an upper portion and a lower portion, which are connected to one another to surround the plurality of rotor blades. Where the upper portion and the lower portion of the compressor casing meet and are joined is typically referred to as a split-line of the compressor section. Traditionally, stator vanes mounted to the compressor casing near the split-line experience higher stresses and are more difficult to assemble and disassemble.

Accordingly, an improved compressor section having a split-line stator vane assembly is desired in the art. In particular, an improved split-line stator vane assembly, that reduces operational stresses, increases hardware life, and simplifies installation, is desired.

<CIT> discloses a gas turbine engine including a combustor section, a turbine section, and a compressor section, the compressor section supporting a stator assembly comprising a plurality of stator vanes. The plurality of stator vanes comprises a split-line stator vane assembly including a first split-line stator vane that has a first shank with a first platform portion and a first mounting portion that extends radially outward of the first platform portion and that is mounted to one of the upper casing portion or the lower casing portion of the compressor casing. A first airfoil extends radially inward of the platform portion. The first shank includes a protrusion that extends circumferentially beyond the split-line. A second split-line stator vane includes a second shank with a second platform portion and a second mounting portion that extends radially outward of the second platform portion and that is mounted to the other of the upper casing portion or the lower casing portion of the compressor casing. A second airfoil extends radially inward of the second platform portion. The second shank includes a recess that extends circumferentially away from the split-line.

<CIT> discloses an array of stator vane segments for a compressor or turbine section of a gas turbine engine, each stator vane segment being separated by an axially extending joint from an adjacent stator vane segment and being releasably mounted to an outer engine casing. Each stator vane segment has: a number of vane airfoils spanning radially between an inner platform and an outer platform, and the outer platform includes a casing mounting fastener on an outer surface and mating lateral joint edges extending between forward and aft edges. The mating lateral joint edges have mating tongues and recesses that define an overlapping joint having a radial thickness equal to the radial thickness of the outer platform. Further <CIT> relates to a prior art turbine split casing.

Aspects and advantages of the compressor sections 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, a compressor section of a turbomachine, according to claim <NUM>, is provided The compressor section includes a compressor casing that has an upper casing portion coupled to a lower casing portion such that a split-line is defined between the upper casing portion and the lower casing portion. A plurality of stator vanes is circumferentially arranged in a stage of the compressor casing. The plurality of stator vanes comprises a split-line stator vane assembly mounted in the compressor casing at the split-line. The split-line stator vane assembly includes a first split-line stator vane that has a first shank with a first platform portion and a first mounting portion that extends radially outward of the first platform portion and that is mounted to one of the upper casing portion or the lower casing portion of the compressor casing. A first airfoil extends radially inward of the platform portion. The first shank includes a protrusion that extends circumferentially beyond the split-line. A second split-line stator vane includes a second shank with a second platform portion and a second mounting portion that extends radially outward of the second platform portion and that is mounted to the other of the upper casing portion or the lower casing portion of the compressor casing. A second airfoil extends radially inward of the second platform portion. The second shank includes a recess that extends circumferentially away from the split-line.

In accordance with another embodiment, a turbomachine is provided. The turbomachine includes a combustor section, a turbine section downstream of the combustor section, and a compressor section upstream of the combustor section, the compressor section configured as described above.

These and other features, aspects and advantages of the present compressor sections and turbomachines will become better understood with reference to the following description and appended claims.

A full and enabling disclosure of the present compressor sections and turbomachines, including the best mode of making and using the present systems and methods, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:.

Reference now will be made in detail to embodiments of the present compressor sections and turbomachines, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation, rather than limitation of, the technology. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present technology without departing from the scope of the claimed technology. Thus, it is intended that the present disclosure covers such modifications and variations as come within the scope of the appended claims and their equivalents.

The term "fluid" may be a gas or a liquid. The term "fluid communication" means that a fluid is capable of making the connection between the areas specified.

As used herein, the terms "upstream" (or "forward") and "downstream" (or "aft") refer to the relative direction with respect to fluid flow in a fluid pathway. However, the terms "upstream" and "downstream" as used herein may also refer to a flow of electricity. The term "radially" refers to the relative direction that is substantially perpendicular to an axial centerline of a particular component, the term "axially" refers to the relative direction that is substantially parallel and/or coaxially aligned to an axial centerline of a particular component and the term "circumferentially" refers to the relative direction that extends around the axial centerline of a particular component.

Terms of approximation, such as "about," "approximately," "generally," and "substantially," are not to be limited to the precise value specified. For example, the approximating language may refer to being within a <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> percent margin in either individual values, range(s) of values and/or endpoints defining range(s) of values. When used in the context of an angle or direction, such terms include within ten degrees greater or less than the stated angle or direction. For example, "generally vertical" includes directions within ten degrees of vertical in any direction, e.g., clockwise or counter-clockwise.

For example, a process, method, article, or apparatus that comprises a list of features is not necessarily limited only to those features but may include other features not expressly listed or inherent to such process, method, article, or apparatus. Further, unless expressly stated to the contrary, "or" refers to an inclusive- or and not to an exclusive- or.

Referring now to the drawings, <FIG> illustrates a schematic diagram of one embodiment of a turbomachine, which in the illustrated embodiment is a gas turbine <NUM>. Although an industrial or land-based gas turbine is shown and described herein, the present disclosure is not limited to a land-based and/or industrial gas turbine unless otherwise specified in the claims. For example, the invention as described herein may be used in any type of turbomachine including but not limited to a steam turbine, an aircraft gas turbine, or a marine gas turbine.

As shown, gas turbine <NUM> generally includes an inlet section <NUM>, a compressor section <NUM> disposed downstream of the inlet section <NUM>, a plurality of combustors (not shown) within a combustor section <NUM> disposed downstream of the compressor section <NUM>, a turbine section <NUM> disposed downstream of the combustor section <NUM>, and an exhaust section <NUM> disposed downstream of the turbine section <NUM>. Additionally, the gas turbine <NUM> may include one or more shafts <NUM> coupled between the compressor section <NUM> and the turbine section <NUM>.

The compressor section <NUM> may generally include a plurality of rotor disks <NUM> (one of which is shown) and a plurality of rotor blades <NUM> extending radially outwardly from and connected to each rotor disk <NUM>. Each rotor disk <NUM> in turn may be coupled to or form a portion of the shaft <NUM> that extends through the compressor section <NUM>.

The turbine section <NUM> may generally include a plurality of rotor disks <NUM> (one of which is shown) and a plurality of rotor blades <NUM> extending radially outwardly from and being interconnected to each rotor disk <NUM>. Each rotor disk <NUM> in turn may be coupled to or form a portion of the shaft <NUM> that extends through the turbine section <NUM>. The turbine section <NUM> further includes an outer casing <NUM> that circumferentially surrounds the portion of the shaft <NUM> and the rotor blades <NUM>, thereby at least partially defining a hot gas path <NUM> through the turbine section <NUM>.

During operation, a working fluid such as air flows through the inlet section <NUM> and into the compressor section <NUM> where the air is progressively compressed, thus providing pressurized air to the combustors of the combustor section <NUM>. The pressurized air is mixed with fuel and burned within each combustor to produce combustion gases <NUM>. The combustion gases <NUM> flow through the hot gas path <NUM> from the combustor section <NUM> into the turbine section <NUM>, wherein energy (kinetic and/or thermal) is transferred from the combustion gases <NUM> to the rotor blades <NUM>, causing the shaft <NUM> to rotate. The mechanical rotational energy may then be used to power the compressor section <NUM> and/or to generate electricity. The combustion gases <NUM> exiting the turbine section <NUM> may then be exhausted from the gas turbine <NUM> via the exhaust section <NUM>.

<FIG> illustrates a cross-sectional side view of an embodiment of the compressor section <NUM> of the gas turbine <NUM> of <FIG>, which is shown as a multi-stage axial compressor section <NUM>, in accordance with embodiments of the present disclosure. As shown in <FIG> and <FIG>, the gas turbine <NUM> may define a cylindrical coordinate system. The cylindrical coordinate system may define an axial direction A (e.g., downstream direction) substantially parallel to and/or along an axial centerline <NUM> of the gas turbine <NUM>, a radial direction R perpendicular to the axial centerline or rotary axis <NUM>, and a circumferential direction C extending around the axial centerline <NUM>.

In operation, air <NUM> may enter the compressor section <NUM> in the axial direction A through the inlet section <NUM> and may be pressurized in the multi-stage axial compressor section <NUM>. The compressed air may then be mixed with fuel for combustion within the combustor section <NUM> to drive the turbine section <NUM>, which rotates the shaft <NUM> in the circumferential direction C and, thus, the multi-stage axial compressor section <NUM>. The rotation of the shaft <NUM> also causes one or more rotor blades <NUM> (e.g., compressor rotor blades) within the multi-stage axial compressor section <NUM> to draw in and pressurize the air received by the inlet section <NUM>.

The multi-stage axial compressor section <NUM> may include a rotor assembly <NUM> having a plurality of rotor disks <NUM>. Rotor blades <NUM> may extend radially outward from the rotor disks <NUM>. The entire rotor assembly <NUM> (e.g., rotor disks <NUM> and rotor blades <NUM>) may rotate in the circumferential direction C during operation of the gas turbine <NUM>. The rotor assembly <NUM> may be surrounded by a compressor casing <NUM>. The compressor casing may be static or stationary, such that the rotor assembly <NUM> rotates relative to the compressor casing <NUM>. Stator vanes <NUM> (e.g., variable stator vanes and/or fixed stator vanes) extend radially inward from the compressor casing <NUM>. As shown in <FIG>, one or more stages of the stator vanes <NUM> may be variable stator vanes, such that an angle of the stator vane <NUM> may be selectively actuated (e.g., by a controller <NUM>). For example, in the embodiments shown in <FIG>, first two stages of the compressor section <NUM> may include variable stator vanes. In many embodiments, as shown, the rotor blades <NUM> and stator vanes <NUM> may be arranged in an alternating fashion, such that most of the rotor blades <NUM> are disposed between two stator vanes <NUM> in the axial direction A.

In some embodiments, the compressor casing <NUM> of the compressor section <NUM> or the inlet section <NUM> may have one or more sets of inlet guide vanes <NUM> (IGVs) (e.g., variable IGV stator vanes). The inlet guide vanes <NUM> may be mounted to the compressor casing <NUM>, spaced apart from one another in the circumferential direction C, and may be operable to control the amount of air <NUM> that enters the compressor section <NUM>. Additionally, an outlet <NUM> of the compressor section <NUM> may have a set of outlet guide vanes <NUM> (OGVs). The OGVs <NUM> may be mounted to the compressor casing <NUM>, spaced apart from one another in the circumferential direction C, and may be operable to control the amount of air <NUM> that exits the compressor section <NUM>.

In exemplary embodiments, as shown in <FIG>, the variable stator vane, the IGVs <NUM>, and the OGVs may each be configured to vary its vane angle relative to the gas flow (e.g., air flow) by rotating the vane, <NUM>, <NUM> about an axis of rotation (e.g., radially oriented vane shaft). However, each variable stator vane (including the IGVs <NUM> and the OGVs <NUM>) may be otherwise stationary relative to the rotor blades <NUM>. In certain embodiments, the variable stator vanes, the IGVs <NUM>, and the OGVs <NUM> may be coupled to an actuator <NUM> (e.g., electric drive, pneumatic drive, or hydraulic drive). The actuators <NUM> may be in operable communication (e.g., electrical communication) with a controller <NUM>. The controller may be operable to selectively vary the vane angle. In other embodiments, all of the stator vanes <NUM> may be fixed, such that the stator vanes <NUM> are configured to remain in a fixed angular position (e.g., the vane angle does not vary).

The compressor section <NUM> may include a plurality of rows or stages arranged in a serial flow order, such as between <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, or <NUM> to <NUM> rows or stages, or any specific number or range therebetween. Each stage may include a plurality of rotor blades <NUM> circumferentially spaced about the axial centerline <NUM> and a plurality of stator vanes <NUM> circumferentially spaced about the axial centerline <NUM>. In each stage, the multi-stage axial compressor section <NUM> may include <NUM> to <NUM>, <NUM> to <NUM>, or <NUM> to <NUM> of circumferentially arranged rotor blades <NUM>, and <NUM> to <NUM>, <NUM> to <NUM>, or <NUM> to <NUM> of circumferentially arranged stator vanes <NUM>. In particular, the illustrated embodiment of the multi-stage axial compressor section <NUM> includes <NUM> stages (e.g., S1-S22).

It may be appreciated that each stage has a set of rotor blades <NUM> disposed at a first axial position and a set of stator vanes <NUM> disposed at a second axial position along the length of the compressor section <NUM>. In other words, each stage has the rotor blades <NUM> and stator vanes <NUM> axially offset from one another, such that the compressor section <NUM> has an alternating arrangement of rotor blades <NUM> and stator vanes <NUM> one set after another along the length of the compressor section <NUM>. Each set of rotor blades <NUM> extends (e.g., in a spaced arrangement) in the circumferential direction C about the shaft <NUM>, and each set of stator vanes <NUM> extends (e.g., in a spaced arrangement) in the circumferential direction C within the compressor casing <NUM>.

While the compressor section <NUM> may include greater or fewer stages than is illustrated, <FIG> illustrates an embodiment of the compressor section <NUM> having twenty two stages arranged in a serial flow order and identified as follows: first stage S1, second stage S2, third stage S3, fourth stage S4, fifth stage S5, sixth stage S6, seventh stage S7, eighth stage S8, ninth stage S9, tenth stage S10, eleventh stage S11, twelfth stage S12, thirteenth stage S13, and fourteenth stage S14, fifteenth stage S15, sixteenth stage S16, seventeenth stage S17, eighteenth stage S18, nineteenth stage S19, twentieth stage S20, twenty-first stage S21, and twenty-second stage S22. In certain embodiments, each stage may include rotor blades <NUM> and stator vanes <NUM> (e.g., fixed stator vanes <NUM> and/or variable stator vanes). As used herein, a rotor blade <NUM> disposed within one of the sections S1-S22 of the compressor section <NUM> may be referred to by whichever stage it is disposed within, e.g., "a first stage compressor rotor blade," "a second stage compressor rotor blade," "a third stage compressor rotor blade," etc..

In use, the rotor blades <NUM> may rotate circumferentially about the compressor casing <NUM> and the stator vanes <NUM>. Rotation of the rotor blades <NUM> may result in air entering the inlet section <NUM>. The air is then subsequently compressed as it traverses the various stages (e.g., first stage S1 to twenty-second stage S22) of the compressor section <NUM> and moves in the axial direction <NUM> downstream of the multi-stage axial compressor section <NUM>. The compressed air may then exit through the outlet <NUM> of the multi-stage axial compressor section <NUM>. As discussed above, the outlet <NUM> may have a set of outlet guide vanes <NUM> (OGVs). The compressed air that exits the compressor section <NUM> may be mixed with fuel, directed to the combustor section <NUM>, directed to the turbine section <NUM>, or elsewhere in the gas turbine <NUM>.

<FIG> each illustrate a schematic cross-sectional view of a compressor section <NUM>, in accordance with embodiments of the present disclosure. Particularly, <FIG> each illustrate a single stage (such as any one of S1-S22 of the compressor section <NUM>) of stator vanes <NUM> circumferentially arranged in, and mounted in, a compressor casing <NUM> of the compressor section <NUM>. As shown, in exemplary embodiments, the compressor casing <NUM> includes an upper casing portion <NUM> and a lower casing portion <NUM>, such that a first half (e.g., about <NUM>%) of the stator vanes <NUM> are mounted in the upper casing portion <NUM> and a second half (e.g., about <NUM>%) of the stator vanes <NUM> are mounted in the lower casing portion <NUM>. During assembly of the compressor section <NUM>, the first half of the stator vanes <NUM> may be installed in the upper casing portion <NUM>, and the second half of the stator vanes <NUM> may be installed in the lower casing portion <NUM>. Subsequently, the upper casing portion <NUM> may be coupled to the lower casing portion <NUM>.

The upper casing portion <NUM> and the lower casing portion <NUM> couple to one another such that a split-line <NUM> is defined between the upper casing portion <NUM> and the lower casing portion <NUM>. The split-line <NUM> may be a horizontal line defined at the junction (e.g., the contact point or plane) of the upper casing portion <NUM> and the lower casing portion <NUM>. In many embodiments, the split-line <NUM> may extend along the radial direction R through a center point of the compressor section <NUM>.

The plurality of stator vanes <NUM> include a split-line stator vane assembly <NUM> mounted in the compressor casing <NUM> at the split-line <NUM>. Particularly, because the upper and lower casing portions <NUM>, <NUM> may connect to one another on two ends, the plurality of stator vanes <NUM> may include two split-line stator vane assemblies <NUM> (e.g., each located at the split-line <NUM> on either side of the compressor casing <NUM>). In various embodiments, the split-line stator vane assembly <NUM> may be disposed in any stage of the compressor section <NUM> (e.g., S1-S22). In some embodiments, the split-line stator vane assembly <NUM> may be disposed in one or more of stages three (S3) through sixteen (S16). However, in exemplary embodiments, the split-line stator vane assembly <NUM> may be disposed in one or more of stages eleven (S11) through sixteen (S16).

As shown schematically in <FIG>, the stator vane assembly <NUM> includes a first split-line stator vane <NUM> mounted in one of the upper casing portion <NUM> or the lower casing portion <NUM>. Additionally, the stator vane assembly <NUM> further includes a second split-line stator vane <NUM> mounted in the other of the upper casing portion <NUM> or the lower casing portion <NUM>, such that the first split-line stator vane <NUM> and the second split-line stator vane <NUM> are disposed adjacent to one another and at least partially contact the split-line <NUM> of the compressor section <NUM>. Particularly, the first split-line stator vane <NUM> includes a protrusion <NUM> that intersects (and extends across) the split-line <NUM> of the compressor section <NUM>, and the second split-line stator vane <NUM> defines a recess <NUM> that that is complementary to the protrusion (such that the recess <NUM> receives the protrusion <NUM>). For example, the recess <NUM> may correspond in shape and size to the protrusion <NUM>, such that they may flushly contact one another when assembled (<FIG>). In this way, the first split-line stator vane <NUM> is mounted in one of the upper casing portion <NUM> or the lower casing portion <NUM>, and the protrusion <NUM> extends across the split-line <NUM> into the recess <NUM> disposed in the second split-line stator vane <NUM> mounted in the other of the upper casing portion <NUM> or the lower casing portion <NUM>.

Additionally, the plurality of stator vanes <NUM> may further include a plurality of main-body stator vanes <NUM> and a plurality of spacers <NUM> mounted in the compressor casing <NUM>. For example, the main-body stator vanes <NUM> and the spacers <NUM> may be mounted in an alternating arrangement in both the upper casing portion <NUM> and the lower casing portion <NUM> between the split-line stator vane assemblies <NUM>. In this way, all of the main-body stator vanes <NUM> and spacers <NUM> in the upper casing portion <NUM> may be disposed circumferentially between a first split-line stator vane assembly <NUM> and a second split-line stator vane assembly <NUM>, such that none of the main-body stator vanes <NUM> or spacers <NUM> in the upper casing portion <NUM> contact or intersect with the split-line <NUM> of the compressor section <NUM>. Similarly, all of the main-body stator vanes <NUM> and spacers <NUM> in the lower casing portion <NUM> may be disposed circumferentially between a first split-line stator vane assembly <NUM> and a second split-line stator vane assembly <NUM>, such that none of the main-body stator vanes <NUM> or spacers <NUM> in the lower casing portion <NUM> contact or intersect with the split-line <NUM> of the compressor section <NUM>.

In many embodiments, the main-body stator vane <NUM> may include a platform portion and a mounting body. The platform portion of the main-body stator vane <NUM> may define a main circumferential width (e.g., measured between the pressure-side slash face and the suction-side slash face). Similarly, the first platform portion <NUM> of the first split-line stator vane <NUM> may define a first circumferential width, and the second platform portion <NUM> of the second split-line stator vane <NUM> may define a second circumferential width. The main circumferential width of the main-body stator vane <NUM> may be smaller than both the first circumferential width of the first split-line stator vane <NUM> and the second circumferential width of the second split-line stator vane <NUM>.

<FIG> illustrates a perspective view of a single stage of stator vanes <NUM> isolated from the compressor casing <NUM>. As shown, the split-line stator vane assemblies <NUM> are circled with a dashed line. For example, the split-line stator vane assemblies <NUM> may include a first split-line stator vane assembly <NUM> at a first end (e.g., a first end of the compressor casing <NUM> at the split-line <NUM>), and a second split-line stator vane assembly <NUM> at a second end (e.g., a second end of the compressor casing <NUM> at the split-line <NUM>). In this way, as shown, the first split-line stator vane assembly <NUM> may be diametrically opposed to the second split-line stator vane assembly <NUM>. Additionally, as shown in <FIG> and <FIG>, each of the main-body stator vanes <NUM> may circumferentially neighbor one of two spacers <NUM> of the plurality of spacers <NUM> or one spacer <NUM> of the plurality of spacers <NUM> and the split-line stator vane assembly <NUM>. For example, each main-body stator vane <NUM> may be positioned between two spacers <NUM>. Additionally, or alternatively, near the split-line <NUM>, one or more main-body stator vanes <NUM> may be disposed between one spacer <NUM> and a split-line stator vane (such as the first split-line stator vane <NUM> or the second split-line stator vane <NUM>).

<FIG> illustrates an enlarged plan view of the first split-line assembly <NUM>, and <FIG> illustrates an enlarged plan view of the second split-line assembly <NUM>, in accordance with embodiments of the present disclosure. As shown, the first split-line stator vane <NUM> and the second split-line stator vane <NUM> may directly neighbor one another when arranged in the compressor casing <NUM>, such that the first split-line stator vane <NUM> and the second split-line stator vane <NUM> are in direct contact with one another (e.g., no spacers or intermediate components positioned between the split-line stator vanes <NUM> and <NUM>). Additionally, the first split-line stator vane <NUM> and the second split-line stator vane <NUM> may each at least partially contact (and/or extend across) the split-line <NUM>. As shown in <FIG>, the protrusion <NUM> extends circumferentially beyond the split-line <NUM> (e.g., beyond the split-line <NUM> and into the recess <NUM> which is correspondingly shaped). Likewise, as shown, the recess <NUM> extends circumferentially away from the split-line <NUM>, in order to define a space for the protrusion <NUM> to extend.

<FIG> illustrates a perspective view of a split-line stator vane assembly <NUM>, and <FIG> each illustrate different perspective views of a first split-line stator vane <NUM> of the split-line stator vane assembly <NUM>, in accordance with embodiments of the present disclosure. As shown, the first split-line stator vane <NUM> includes a first shank <NUM> having a first platform portion <NUM> and a first mounting portion <NUM>. The protrusion <NUM> is defined by the shank <NUM> (i.e., collectively defined by the first platform portion <NUM> and the first mounting portion <NUM>). Additionally, the first mounting portion <NUM> extends radially outward of the first platform portion <NUM>. The first mounting portion <NUM> is mounted to one of the upper casing portion <NUM> or the lower casing portion <NUM> of the compressor casing <NUM>. In many embodiments, the first mounting portion <NUM> may include a protrusion <NUM> that is slidably received by a corresponding recess defined in the compressor casing <NUM>. For example, the first mounting portion <NUM> may be a dovetail or other suitable mounting construction that is slidably received by a correspondingly shaped slot defined in the compressor casing <NUM>.

Likewise, as shown, the second split-line stator vane <NUM> includes a second shank <NUM> having a second platform portion <NUM> and a second mounting portion <NUM>. The recess <NUM> is defined by the second shank <NUM> (i.e., collectively defined by the second platform portion <NUM> and the second mounting portion <NUM>). Additionally, the second mounting portion <NUM> extends radially outward of the second platform portion <NUM>. The second mounting portion <NUM> is mounted to one of the upper casing portion <NUM> or the lower casing portion <NUM> of the compressor casing <NUM>. Particularly, the second mounting portion <NUM> is mounted to the other of the upper casing portion <NUM> or the lower casing portion <NUM> that the first mounting portion <NUM> is mounted on. For example, if the first split-line stator vane <NUM> is attached to the upper casing portion <NUM>, then the second split-line stator vane <NUM> would be mounted to the lower casing portion <NUM> (and vice versa). In many embodiments, the second mounting portion <NUM> may include a protrusion <NUM> that may be slidably received by a corresponding recess defined in the compressor casing <NUM>. For example, the second mounting portion <NUM> may be a dovetail or other suitable mounting construction that is slidably received by a correspondingly shaped slot defined in the compressor casing <NUM>.

Each of the stator vanes <NUM> described herein, including the first split-line stator vane <NUM>, the second split-line stator vane <NUM>, and the main-body stator vanes <NUM>, includes an airfoil <NUM> that extends radially inwardly from the respective platform portion of the respective stator vane when the stator vane is mounted in the casing <NUM>. Each airfoil <NUM> may include a pressure-side surface <NUM> and an opposing suction-side surface <NUM>. The pressure-side surface <NUM> and the suction-side surface <NUM> meet or intersect at a leading edge <NUM> and a trailing edge <NUM> of the airfoil <NUM>. The leading edge <NUM> and the trailing edge <NUM> may be spaced apart from one another and define the terminal ends of the airfoil <NUM>.

The pressure-side surface <NUM> generally defines an aerodynamic, concave external surface of the airfoil <NUM>. Similarly, the suction-side surface <NUM> may generally define an aerodynamic, convex external surface of the airfoil <NUM>. The leading edge <NUM> of airfoil <NUM> may be the first portion of the airfoil <NUM> to engage, i.e., be exposed to, the compressed air within the compressor section <NUM>. Compressed air may be guided along the aerodynamic contour of airfoil <NUM> from the leading edge <NUM> to the trailing edge <NUM>.

In many embodiments, each airfoil <NUM> may include a root or first end <NUM>, which intersects with and extends radially outwardly from the respective platform portion of the stator vane. Each airfoil <NUM> terminates radially at a second end or tip <NUM> of the airfoil <NUM>. The root <NUM> of the airfoil <NUM> may be defined at an intersection between the airfoil <NUM> and the platform portion of the stator vane.

In exemplary embodiments, as shown best in <FIG>, the first shank <NUM> may define a first pressure-side slash face <NUM> and a first suction-side slash face <NUM>. The first pressure-side slash face <NUM> and the first suction-side slash face <NUM> may be circumferentially spaced apart from one another and disposed on opposite sides of the airfoil <NUM>. Similarly, the second shank <NUM> may define a second pressure-side slash face <NUM> and a second suction-side slash face <NUM>. The second pressure-side slash face <NUM> and the second suction-side slash face <NUM> may be circumferentially spaced apart from one another and disposed on opposite sides of the airfoil <NUM>.

In many embodiments, as shown, the first pressure-side slash face <NUM> contacts the second suction-side slash face <NUM>. For example, the first pressure-side slash face <NUM> of the first split-line stator vane <NUM> and the second suction-side slash face <NUM> of the second split-line stator vane <NUM> may be entirely in contact with one another (e.g., both faces <NUM> and <NUM> may be contoured to correspond with one another such that they are in flush contact). Particularly, in exemplary embodiments, the protrusion <NUM> may be defined on the first pressure-side slash face <NUM>, and the recess <NUM> may be defined on the second suction-side slash face <NUM>. In this way, the protrusion <NUM> of the first split-line stator vane <NUM> may be entirely in contact with the recess <NUM> of the second split-line stator vane <NUM>.

In many embodiments, the first suction-side slash face <NUM> and the second pressure-side slash face <NUM> are planar surfaces (e.g., entirely planar surfaces). For example, as shown, the first suction-side slash face <NUM> and the second pressure-side slash face <NUM> may be substantially flat surfaces (e.g., not including any curvatures, protrusions, or recesses). This allows the first suction-side slash face <NUM> and the second pressure-side slash face <NUM> to be in flush contact with one of a spacer <NUM> or a main-body stator vane <NUM> when installed in the casing <NUM> of the compressor section <NUM>.

Additionally, in many embodiments, the first pressure-side slash face <NUM> includes a first planar portion <NUM>, and the second suction-side slash face <NUM> includes a second planar portion <NUM>. The first planar portion <NUM> and the second planar portion <NUM> may be generally parallel to one another and generally parallel to the first suction-side slash face <NUM> and the second pressure-side slash face <NUM>. For example, the first planar portion <NUM> and the second planar portion <NUM> may be aligned with the split-line <NUM>. In exemplary embodiments, as shown best in <FIG>, a portion <NUM> of the airfoil <NUM> belonging to the first split-line stator vane <NUM> is coupled to the protrusion <NUM> of the first split-line stator vane <NUM> such that the portion <NUM> of the first airfoil extends circumferentially beyond the split-line <NUM>. For example, the portion <NUM> may include the leading edge <NUM> of the airfoil <NUM>.

Claim 1:
A compressor section (<NUM>) of a turbomachine (<NUM>) comprising:
a compressor casing (<NUM>) having an upper casing portion (<NUM>) coupled to a lower casing portion (<NUM>) such that a split-line (<NUM>) is defined between the upper casing portion (<NUM>) and the lower casing portion (<NUM>); and
a plurality of stator vanes (<NUM>) circumferentially arranged in a stage of the compressor casing (<NUM>), the plurality of stator vanes (<NUM>) comprising a split-line stator vane assembly (<NUM>) mounted in the compressor casing (<NUM>) at the split-line (<NUM>), the split-line stator vane assembly (<NUM>), characterized in further comprising:
a first split-line stator vane (<NUM>) having a first shank (<NUM>) with a first platform portion (<NUM>) and a first mounting portion (<NUM>) extending radially outward of the first platform portion (<NUM>) and mounted to one of an upper casing portion (<NUM>) or a lower casing portion (<NUM>) of the compressor casing (<NUM>), and a first airfoil (<NUM>) extending radially inward of the first platform portion (<NUM>), wherein the first shank (<NUM>) includes a protrusion (<NUM>) that extends circumferentially beyond the split-line (<NUM>); and
a second split-line stator vane (<NUM>) having a second shank (<NUM>) with a second platform portion (<NUM>) and a second mounting portion (<NUM>) extending radially outward of the second platform portion (<NUM>) and mounted to the other of the upper casing portion (<NUM>) or the lower casing portion (<NUM>) of the compressor casing (<NUM>), and a second airfoil (<NUM>) extending radially inward of the second platform portion (<NUM>), wherein the second shank (<NUM>) includes a recess (<NUM>) complementary to the protrusion (<NUM>) that extends circumferentially away from the split-line (<NUM>).