Patent Description:
Gas turbine engines can include a fan for propulsion air and to cool components. The fan also delivers air into a core engine where it is compressed. The compressed air is then delivered into a combustion section, where it is mixed with fuel and ignited. The combustion gas expands downstream over and drives turbine blades. Static vanes are positioned adjacent to the turbine blades to control the flow of the products of combustion. The blades and vanes are subject to extreme heat, and thus cooling schemes are utilized for each.

<CIT> discloses five serpentine radially extending cooling passages formed in a gas turbine stationary vane airfoil.

<CIT> discloses baffles formed integrally with a wall within an airfoil.

The baffles comprise wedge sections and split the cooling passage into two sections. <CIT> discloses a gas turbine airfoil comprising a cooling passage, wherein a baffle is inserted inside the cooling passage.

From a first aspect, the invention provides an airfoil as claimed in claim <NUM>.

In an embodiment, the apex of the first wedge region is oriented in a direction towards an outer wall of the turn section.

In a further embodiment of any of the forgoing embodiments, the apex is arranged such that a division of the fluid flow into the two cooling flow paths at the apex is within a predetermined range, such that the fluid flow through each of the first and second flow paths is equal.

In a further embodiment of any of the forgoing embodiments, the baffle is arranged in the internal passage such that a ratio of a volume of one of the two cooling flow paths and a volume of another one of the cooling flow paths in the turn section is within a predetermined range, to provide different cooling augmentation to portions of the airfoil adjacent to the cooling flow paths.

In a further embodiment of any of the forgoing embodiments, the body defines a hollow interior, and the baffle defines one or more openings configured to communicate coolant flow between the hollow interior and the internal passage.

In a further embodiment of any of the forgoing embodiments, the baffle is elongated, and a cross-section of the baffle taken transverse to a longitudinal direction of the baffle at the turn section has five to seven distinct sides.

In a further embodiment of any of the forgoing embodiments, the second wedge region abuts a terminal end of a rib separating the first and second passage sections, the rib defining a notch configured to receive a portion of the second wedge region such that the portion of the second wedge region is radially inboard of a radially outermost portion of the terminal end of the rib.

In a further embodiment of any of the forgoing embodiments, one of the two cooling flow paths is bounded by a pressure side of the airfoil body, and another one of the two cooling flow paths is bounded by a suction side of the airfoil body.

In a further embodiment of any of the forgoing embodiments, the airfoil body extends from a platform section, and the platform section defines a cavity configured to at least partially receive the baffle.

From a further aspect, the invention provides an airfoil as claimed in claim <NUM>.

In a further embodiment of any of the forgoing embodiments, the apex is offset towards one of the opposed walls.

In a further embodiment of any of the forgoing embodiments, a cross-section of the baffle taken at one of the first wedge region and the second wedge region has five to seven distinct sides.

From a still further aspect, the invention provides a gas turbine engine as claimed in claim <NUM>.

In a further embodiment of any of the forgoing embodiments, the apex of the first wedge region is arranged in the turn section such that a division of the fluid flow into each of the at least two cooling paths at the apex is within a predetermined range, to provide different cooling augmentation to portions of the airfoil adjacent to the cooling flow paths.

In a further embodiment of any of the forgoing embodiments, the apex slopes towards a rib of the airfoil body separating the first and second passage sections.

In a further embodiment of any of the forgoing embodiments, the airfoil body extends from a platform section, and an end portion of the baffle extends through the platform section.

In a further embodiment of any of the forgoing embodiments, the second wedge region extends from the body into the first passage section, the first wedge region slopes inwardly from opposed walls of the body.

In a further embodiment of any of the forgoing embodiments, the internal passage is a serpentine passage.

The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of an embodiment.

The concepts described herein are not limited to use with turbofans and may be applied to other types of turbine engines, such as three-spool architectures. Alternative engines might also include an augmentor section (not shown) among other systems or features, or, may not include the fan section <NUM>, such as in industrial gas turbine engines.

Although depicted as a two-spool turbofan gas turbine engine in the disclosed non-limiting embodiment, the examples herein are not limited to use with two-spool turbofans and may be applied to other types of turbomachinery, including direct drive engine architectures, three-spool engine architectures, and ground-based turbines.

The engine <NUM> generally includes a low speed spool <NUM> and a high speed spool <NUM> mounted for rotation about an engine central longitudinal axis A relative to an engine static structure <NUM> via several bearing systems <NUM>.

The low speed spool <NUM> generally includes an inner shaft <NUM> that interconnects a fan <NUM>, a first (or low) pressure compressor <NUM> and a second (or low) pressure turbine <NUM>. The inner shaft <NUM> is connected to the fan <NUM> through a speed change mechanism, which in exemplary gas turbine engine <NUM> is illustrated as a geared architecture <NUM>, to drive the fan <NUM> at a lower speed than the low speed spool <NUM>.

The high speed spool <NUM> includes an outer shaft <NUM> that interconnects a second (or high) pressure compressor <NUM> and a first (or high) pressure turbine <NUM>. A combustor <NUM> is arranged between the high pressure compressor <NUM> and the high pressure turbine <NUM>. The mid-turbine frame <NUM> further supports the bearing systems <NUM> in the turbine section <NUM>. The inner shaft <NUM> and the outer shaft <NUM> are concentric and rotate via bearing systems <NUM> about the engine central longitudinal axis A, which is collinear with their longitudinal axes.

The geared architecture <NUM> may be an epicycle gear train, such as a planetary gear system or other gear system, with a gear reduction ratio of greater than about <NUM>:<NUM>. It should be understood, however, that the above parameters are only exemplary of one embodiment of a geared architecture engine and that the present invention is applicable to other gas turbine engines, including direct drive turbofans.

The fan section <NUM> of the engine <NUM> is designed for a particular flight condition -- typically cruise at about <NUM> Mach and about <NUM>,<NUM> feet (<NUM>,<NUM>). The flight condition of <NUM> Mach and <NUM>,<NUM> ft (<NUM>,<NUM>), with the engine at its best fuel consumption - also known as "bucket cruise Thrust Specific Fuel Consumption ('TSFC')" - is the industry standard parameter of lbm of fuel being burned divided by lbf of thrust the engine produces at that minimum point. "Low corrected fan tip speed" is the actual fan tip speed in ft/sec divided by an industry standard temperature correction of [(Tram °R) / (<NUM> °R)]<NUM> (where R° = K x <NUM>/<NUM>). The "Low corrected fan tip speed" as disclosed herein according to one non-limiting embodiment is less than about <NUM> ft / second (<NUM>/s).

<FIG> illustrates a portion of the turbine section <NUM>/<NUM>, such as one of the high or low pressure turbines <NUM>, <NUM>, which includes an airfoil <NUM>. In this disclosure, like reference numerals designate like elements where appropriate and reference numerals with the addition of one-hundred or multiples thereof designate modified elements that are understood to incorporate the same features and benefits of the corresponding original elements. In this example, the airfoil <NUM> is a vane that is situated between two rotatable blades <NUM>. It is to be understood that although the examples herein are described with respect to the airfoil <NUM> as a vane, the examples are also applicable to rotatable blades (airfoils) or other airfoils in other sections of the engine <NUM>, including other sections of the turbine section <NUM>/<NUM> or the compressor section <NUM>/<NUM>.

The airfoil <NUM> includes an airfoil body <NUM> extending in a radial direction R between platforms <NUM>. The airfoil body <NUM> extends in a chordwise direction C between a leading edge <NUM> and a trailing edge <NUM>, and in a circumferential or thickness direction T between pressure and suction sides P, S (<FIG>). The airfoil body <NUM> has an internal passage <NUM> that serves to convey a fluid flow F through the airfoil <NUM>. For example, the fluid flow F can be relatively cool air from the compressor section <NUM> or an upstream stage of the turbine section <NUM>. Although not limited, the internal passage <NUM> in this example is a serpentine passage that winds radially back and forth within the airfoil body <NUM> with one or more ribs <NUM> separating the passage sections of the internal passage <NUM>. In this regard, the internal passage <NUM> includes at least a first passage section <NUM> and a second passage section <NUM> separated by one of the ribs <NUM>. A bend or turn section <NUM> connects the first and second passage sections <NUM>, <NUM>. The fluid flow F is thus conveyed through the internal passage <NUM> and is then discharged into the core flow path C through holes or openings in the airfoil body <NUM>. Although the first and second passage sections <NUM>, <NUM> are depicted as extending in the radial direction R, and the turn section <NUM> is depicted as turning approximately <NUM> degrees, it should be appreciated that the first and second passage sections <NUM>, <NUM> and turn section <NUM> can be arranged at different orientations relative to each other and/or relative to the engine axis A to provide the desired cooling augmentation.

Referring to <FIG>, a baffle <NUM> is situated in the internal passage <NUM> of the airfoil <NUM> to reduce an effective volume of the internal passage <NUM>. <FIG> illustrates an axially-sectioned view of the airfoil <NUM>. <FIG> illustrates a sectioned, radially outward view of the airfoil <NUM> taken along line 3B-3B. <FIG> illustrates a perspective view of the airfoil <NUM> of <FIG> in cross-section (with platform <NUM> omitted). <FIG> illustrates an axially-sectioned view of the airfoil <NUM> taken along line 3D-3D. Although the baffle <NUM> is situated adjacent to a leading edge <NUM> of the airfoil <NUM>, it should be understood that the baffle <NUM> can be situated in other locations of the internal passage <NUM>, such as in a passage section adjacent to a trailing edge <NUM> of the airfoil <NUM> or an intermediate passage section of the internal passage <NUM>. The baffle <NUM> can be arranged to join or divide fluid flow F at radially inner portions of the internal passage <NUM> (<FIG>) and/or radially outer portions of the internal passage <NUM>, for example.

In the illustrated example, the baffle <NUM> is situated in the second passage section <NUM> and the turn section <NUM>. In some examples, the baffle <NUM> is fabricated of a metal or metal alloy, such as sheet metal, by additive manufacturing, by casting, or the like. The baffle <NUM> is configured to occupy a volume of the second passage section <NUM> to provide a desired cooling augmentation to portions of the airfoil body <NUM> adjacent to the baffle <NUM> or other heat loads.

The baffle <NUM> is arranged in the internal passage <NUM> to bound or otherwise define at least two cooling flow paths together with surfaces of the internal passage <NUM>. In the illustrated example, the baffle <NUM> is arranged in the internal passage <NUM> to define two cooling flow paths F1, F2 (<FIG>). The baffle <NUM> extends at least partially between the turn section <NUM> and the second passage section <NUM> such that the fluid flow F is directed through the turn section <NUM> between the first passage section <NUM> and the two cooling flow paths F1, F2. Accordingly, the baffle <NUM> is arranged in the internal passage <NUM> such that there is a radial and axial splitting of the fluid flow F in the two cooling flow paths F1, F2 with respect to the engine axis A (<FIG>).

At least a portion of the baffle <NUM> is spaced from surfaces of the second passage section <NUM> such that one of the two cooling flow paths F1 is bounded by pressure side P of the airfoil body <NUM>, and another one of the two cooling flow paths F2 is bounded by a suction side S of the airfoil body <NUM>. In other examples, portions of baffle <NUM> extends in a circumferential direction to abut opposed surfaces of the second passage section <NUM>, thereby defining a desired volume through the first and second flow paths F1, F2. The first and second flow paths F1, F2 are bounded by outermost surfaces 70D (<FIG>) of the turn section <NUM>. The arrangements disclosed herein improve flow distribution through the turn section <NUM> by reducing flow separation of the first and second flow paths F1, F2 at the turn section <NUM>.

Referring to <FIG>, with continued reference to <FIG>, an isolated view of the baffle <NUM> is shown. The baffle <NUM> includes a body <NUM> extending in a longitudinal direction <NUM>, which can be parallel or substantially parallel to the radial direction R with respect to the engine axis A. The body <NUM> is elongated in the longitudinal direction <NUM> such that the body <NUM> occupies a desired volume of the second passage section <NUM>. In the illustrated example, the first passage section <NUM> is free of the body <NUM> when the baffle <NUM> is located in an installed position (<FIG>). In alternative examples, at least a portion of the body <NUM> extends into the first passage section <NUM>.

In the illustrated example of <FIG>, the body <NUM> defines a hollow interior <NUM> for conveying a secondary fluid flow. The baffle <NUM> defines one or more cooling holes or openings <NUM> for discharging or otherwise conveying flow from the hollow interior <NUM> to selected portions of the internal passage <NUM>, such as one of the cooling flow paths F1, F2 at the turn section <NUM>, to provide a desired cooling augmentation through mixing of flow through the hollow interior <NUM> with the fluid flow F. The cooling holes <NUM> can be arranged such that flow is distributed in an axial and/or radial direction along external surfaces of the baffle <NUM> to reduce cooling air heat pickup and pressure loss. In some examples, a radially inner (or first) end portion <NUM> (<FIG>) of the baffle <NUM> is configured to receive a portion of coolant flow from the second passage section <NUM> such that that the coolant flow is communicated through the hollow interior <NUM> and is discharged at the cooling holes <NUM> located at a radially outer (or second) end of the baffle <NUM>. Utilizing this technique, the coolant flow from the hollow interior <NUM> of the baffle <NUM> is slowly diffused downstream at the turn section <NUM> and into the first passage section <NUM> to reduce downstream flow separation and pressure loss. In alternative examples, the hollow interior <NUM> is fluidly closed with respect to the internal passage <NUM> when the baffle <NUM> is located in an installed position (<FIG>). Although a hollow interior <NUM> is depicted, in alternative examples a volume of the body <NUM> is occupied by material to provide a desired rigidity.

The baffle <NUM> includes a first wedge region <NUM> configured to be received in at least the turn section <NUM> of the internal passage <NUM>. The first wedge region <NUM> includes a first sloped side 76A and a second sloped side 76B that slope inwardly from opposed walls 77A, 77B of the baffle <NUM> and are joined at an apex 76C. In the illustrated example, the apex 76C forms a defined edge. In other examples, the apex 76C is rounded to provide a smooth transition between the first passage section <NUM> and the turn section <NUM>. The apex 76C is arranged in the internal passage <NUM> to divide and/or join the fluid flow F in the circumferential or thickness direction T between the first and second passage portions <NUM>, <NUM> through the turn section <NUM>.

When the baffle <NUM> is located in an installed position, the apex 76C is oriented in a direction <NUM> (<FIG>) transverse to the longitudinal direction <NUM> of the baffle <NUM> such that a projection of the apex 76C intersects an outer wall 70C of the turn section <NUM>. In a further example, a length of the apex 76C is oriented in the longitudinal direction <NUM> such a projection of the apex 76C along the length intersects the platform <NUM>. In the illustrated example, the apex 76C is offset towards wall 77A and away from opposed wall 77B. In alternative examples, the apex 76C is positioned substantially between the opposed walls 77A, 77B.

The baffle <NUM> includes a second wedge region <NUM> configured to be received in at least the turn section <NUM> of the internal passage <NUM>. The second wedge region <NUM> includes a third sloped side 78A and a fourth sloped side 78B that slope inwardly from the first and second sloped sides 76A, 76B of the first wedge region <NUM> and towards the body <NUM>. The sloped sides 78A, 78B are joined at an apex 78C. In the illustrated example, the apex 78C is substantially aligned in the longitudinal direction <NUM> with apex 76C of the first wedge portion <NUM>, and slopes inwardly from an end of the apex 76C towards the body <NUM>. The second wedge region <NUM> slopes inwardly from the first wedge region <NUM> towards the body <NUM> such that the second wedge region <NUM> is spaced from outer surfaces of the turn section <NUM> (shown in <FIG>).

Each of the first and second wedge regions <NUM>, <NUM> extends from the body <NUM> into the first passage section <NUM> such that the fluid flow F is directed through the turn section <NUM> between the first passage section <NUM> and the two cooling flow paths F1, F2. Thus, the first and second wedge regions <NUM>, <NUM> extend through a reference plane R<NUM> (<FIG>) defined by the rib <NUM>. When the fluid flow F is communicated in a first direction from the first passage section <NUM> to the first and section flow paths F <NUM>, F2, the second wedge region <NUM> serves to begin accelerating a velocity of the radial component of fluid flow F by gradually lowering an effective cross-sectional area of the turn section <NUM>, while the first wedge region <NUM> gradually accelerates the axial component of fluid flow F in turn section <NUM>. The incorporation of the second wedge region <NUM> allows the first wedge region <NUM> to extend farther into first passage section <NUM> and turn section <NUM> without disrupting the cooling flow and creating a relatively large pressure loss. The orientation and/or geometry of the first and second wedge regions <NUM>, <NUM> can be selected to reduce pressure loss at an inlet to the turn section <NUM> and/or an exit of the turn section <NUM> for an accelerating or diffusing flow field condition.

A cross-section of the baffle <NUM> includes at least two distinct sides defined by wedge regions <NUM>, <NUM> to divide and/or join flow through the turn section <NUM>. For the purposes of this disclosure, adjacent distinct sides are defined by a corresponding inflection. Thus, the wedge regions <NUM>, <NUM> can include distinct edges or can have contoured surfaces with no discrete edges. In the illustrated example, a cross-section of the baffle <NUM> taken transverse to a longitudinal direction <NUM> of the baffle <NUM> has five to seven distinct sides, such as five distinct sides at the first wedge region <NUM> (<FIG>) and seven distinct sides at the second wedge region <NUM> (<FIG>). Each of the cross-sections through the first and second wedge regions <NUM>, <NUM> can be taken at the turn section <NUM> transverse to the reference plane Ri (<FIG>) of rib <NUM> when the baffle <NUM> is located in an installed position.

Although the apexes 76C, 78C and other edges of the sloped sides 76A, 76B, 78A, 78B are depicted having sharp or otherwise distinct edges, it should be appreciated that the edges can be beveled, filleted or rounded, or otherwise contoured to reduce pressure loss and flow instability. In the illustrated example, the sloped sides 76A, 76B, 78A, 78B are planar or substantially planar. In alternative examples, at least some of the sloped sides 76A, 76B, 78A, 78B may comprise convex surfaces, concave surfaces, or be defined as more complex surfaces, consisting of multiple compound shapes having one or more inflection points. The arrangement of these geometric features (76A, 76B, 78A, and/or 78B) enables the tailoring of near wall and bulk coolant momentum and thermal boundary layer flow characteristics, velocity profiles and pressure gradients which directly affect local flow instability, pressure loss, and heat transfer performance.

Referring to <FIG>, the fluid flow F can be communicated in a first direction in the internal passage <NUM> such that the first and second wedge regions <NUM>, <NUM> branch or otherwise divide the fluid flow F from the first passage section <NUM> to the first and section flow paths F <NUM>, F2. In some examples, the first and second wedge regions <NUM>, <NUM> are situated in the turn section <NUM> such that the fluid flow F is partially or fully diverted into (or entirely distributed between) the first and second flow paths F1, F2 (and around an exterior of the baffle <NUM>) before entering the second passage section <NUM>. In another example, the fluid flow F is communicated in a second, different direction such that the first and second wedge regions <NUM>, <NUM> join the fluid flow F from the first and section flow paths F <NUM>, F2 to the first passage section <NUM>. Regardless of the direction of fluid flow, the wedge regions <NUM>, <NUM> are situated in the turn section <NUM> to provide a smooth or otherwise gradual transition to guide the fluid flow F1 through the turn section <NUM> between the first passage section <NUM> and first and section flow paths F1, F2. Accordingly, pressure loss through the turn section <NUM> caused by abrupt changes and flow separation in the flow path can be reduced. Additionally, vortices and other instabilities in the flow path during joining of the fluid flow can be reduced.

The baffle <NUM> is arranged in the turn section <NUM> such that a division of the fluid flow into or through the two cooling flow paths F1, F2 at the apex 76C, 78C is within a predetermined range. In one example, the baffle <NUM> is arranged in the internal passage <NUM> such that a ratio of a volume of one of the two cooling flow paths F1, F2 and a volume of another one of the cooling flow paths F1, F2 in the turn section <NUM> is within a predetermined range. The relative flow distribution can be tailored at the inlet and/or exit of the turn section <NUM>, as well as through the turn section <NUM>, based on the geometry distribution, surface contour, and relative location of the protrusion formed by sloped sides 76A, 76B, 78A, and 78B, and the apex 76C and 78C in passage <NUM>. The first and second flow paths F1, F2 can be selected such that the fluid flow through each of the first and second flow paths F1, F2 is substantially equal, or can be selected to provide different cooling augmentation to portions of the airfoil <NUM> adjacent to the first and second flow paths F1, F2 such that the overall cooling demand and/or supply pressure can be reduced.

For example, apex 76C and/or 78C can be situated in the turn section <NUM> such that a projection of the apex 76C and/or 78C along the direction <NUM> generally bisects a cross-sectional area of the internal passage <NUM> at the turn section <NUM>. In alternative examples, a projection of the apex 76C and/or 78C along the direction <NUM> can be such that a cross-sectional area of first and second flow paths F1, F2 at the turn section <NUM> differ. Utilizing this technique, an offset of apex 76C and/or apex 78C provides different distributions of the fluid flow F though the first and second flow paths F1, F2 depending on the desired relative cooling capacities.

In another example, the first sloped side 76A defines a reference plane intersecting localized surfaces 70A of the turn section <NUM> to define a first angle ΘA. Similarly, the second sloped side 76B defines a reference plane intersecting localized surfaces 70B of the turn section <NUM> to define a second angle ΘB. For the purposes of this disclosure, the reference plane corresponds to a geometry or profile of the corresponding sloped side, such as sloped sides 76A, 76B. The reference plane can be substantially planar, or can have a curved profile characterized by a rate of curvature of the corresponding sloped side, for example. The first and second angles ΘA, ΘB can be taken at a tangent of the corresponding localized surfaces 70A, 70B of the turn section <NUM>. In some examples, the first and/or second angles ΘA, ΘB are equal to or less than <NUM> degrees, or more narrowly between <NUM> degrees and <NUM> degrees. In some examples, the first and/or second angles ΘA, ΘB differ, and in other examples, the first and/or second angles ΘA, ΘB are equal or substantially equal.

In some examples, the sloped sides 78A, 78B of the second wedge region <NUM> arranged in a similar manner, including any of the angles of the sloped sides 76A, 76B disclosed herein. Regardless of the particular shape and orientations, the sloped sides 76A, 76B, 78A, 78B can be acutely angled or positioned with respect to one another to gradually divert or join the fluid flow F through the turn section <NUM>. In this manner, a volume of the fluid flow F communicated through each of the first and second flow paths F1, F2 in the turn section <NUM> is within a predetermined range.

Referring again to <FIG>, the second wedge region <NUM> abuts a terminal end <NUM> of rib <NUM> separating the first and second passage sections <NUM>, <NUM>. In the illustrated example, the rib <NUM> defines a locating feature or notch <NUM> extending radially inwardly from the terminal end <NUM>. The notch <NUM> has a geometry complementary to the second wedge region <NUM>, such as generally V-shaped profile. The notch <NUM> is configured to receive a portion of the second wedge region <NUM> such that the portion of the second wedge region <NUM> is radially inboard of a radially outermost portion of the terminal end <NUM> of the rib <NUM>. In this example, a portion of the second wedge region <NUM> extends a distance in the first passage section <NUM> radially inward of the turn section <NUM> bounded by a radially outermost portion of the terminal end <NUM> of rib <NUM>. Thus, the notch <NUM> limits or otherwise reduces radial, axial and/or circumferential movement of the baffle <NUM> in the internal passage <NUM>. The body <NUM> is configured to abut surfaces of the second passage section <NUM> and the rib <NUM> to reduce axial and/or circumferential movement of the baffle <NUM> (<FIG>).

In the illustrated example, the apex 78C slopes inwardly from an end of the apex 76C towards the rib <NUM> when the baffle <NUM> is located in an installed position. The second wedge region <NUM> is arranged relative to the body <NUM> and first wedge region <NUM> such that second wedge region <NUM> is spaced apart from outer surfaces of the turn section <NUM> when in the installed position.

The platform <NUM> defines a cavity <NUM> dimensioned to receive a portion of the baffle <NUM>. An end of the baffle <NUM> extends radially outward from the turn section <NUM> of the internal passage <NUM>. The cavity <NUM> can be configured to seal against or abut the baffle <NUM> such that the turn section <NUM> and radially outward portions of the platform <NUM> are fluidly isolated from each other. In alternative examples, the baffle <NUM> terminates radially inward from the platform <NUM> at the turn section <NUM>.

<FIG> depicts an exploded view of an airfoil <NUM> and a baffle <NUM> according to a second embodiment. The baffle <NUM> defines a ledge <NUM> configured to abut a floor <NUM> of notch <NUM>. The apex 178C terminates at the ledge <NUM>. The floor <NUM> is configured to position the baffle <NUM> at a desired position radially in the second passage section <NUM> and turn section <NUM>.

Referring to <FIG> (installed position) and <FIG> (uninstalled position), for installation, an end of the baffle <NUM>/<NUM> is moved from a radially outward direction to a radially inward direction into the cavity <NUM>/<NUM>. The end of the baffle <NUM>/<NUM> is moved in the radially inward direction through the cavity <NUM>/<NUM> and into the second passage section <NUM>/<NUM> such that the second wedge region <NUM> abuts the notch <NUM>. The baffle <NUM>/<NUM> can be welded or otherwise attached to surfaces of the internal passage <NUM>/<NUM>, rib <NUM>/<NUM> and/or cavity <NUM>/<NUM> to secure the baffle <NUM>/<NUM> in the internal passage <NUM>/<NUM>. In another example, the baffle <NUM>/<NUM> is situated in the internal passage <NUM>/<NUM> utilizing a casting or additive manufacturing technique.

Claim 1:
An airfoil (<NUM>; <NUM>) for a gas turbine engine (<NUM>), comprising:
an airfoil body (<NUM>; <NUM>) having an internal passage (<NUM>; <NUM>) for conveying a fluid flow (F), the internal passage (<NUM>; <NUM>) including first and second passage sections (<NUM>, <NUM>; <NUM>) coupled at a turn section (<NUM>; <NUM>), wherein the first and second passage sections are separated by a rib,
wherein the airfoil comprises a baffle (<NUM>; <NUM>) including a body (<NUM>) arranged in the second passage section (<NUM>; <NUM>) to define two cooling flow paths (F1, F2) together with surfaces of the internal passage (<NUM>; <NUM>), and a first wedge region (<NUM>; <NUM>) extending from the body (<NUM>) into the first passage section (<NUM>) such that the fluid flow (F) is directed through the turn section (<NUM>; <NUM>) between the first passage section (<NUM>) and the two cooling flow paths (F1, F2),
wherein the first wedge region (<NUM>; <NUM>) includes first and second sloped sides (76A, 76B) that are joined at an apex (76C), the first sloped side (76A) defining a first reference plane intersecting a surface of the turn section (<NUM>; <NUM>) to define a first angle (ΘA), the first angle (ΘA) being equal to or less than <NUM> degrees,
wherein the baffle (<NUM>; <NUM>) includes a second wedge region (<NUM>; <NUM>) sloping inwardly from the first wedge region (<NUM>; <NUM>) towards the body (<NUM>) such that the second wedge region (<NUM>; <NUM>) is spaced from outer surfaces of the turn section (<NUM>; <NUM>).