(19)
(11)EP 2 538 025 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
08.08.2018 Bulletin 2018/32

(21)Application number: 12172488.4

(22)Date of filing:  18.06.2012
(51)International Patent Classification (IPC): 
F01D 5/18(2006.01)

(54)

Hot gas path component and corresponding method of forming a component

Bauteil für Heissgasstrom und zugehöriges Verfahren zur Herstellung eines Bauteils

Composant de passage de gaz chaud et procédé associé de fabrication d'un composant


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 20.06.2011 US 201113164113

(43)Date of publication of application:
26.12.2012 Bulletin 2012/52

(73)Proprietor: General Electric Company
Schenectady, NY 12345 (US)

(72)Inventors:
  • Itzel, Gary Michael
    Greenville, SC South Carolina 29615 (US)
  • Pal, Dipankar
    Greenville, SC South Carolina 29615 (US)

(74)Representative: Fischer, Michael Maria et al
General Electric Technology GmbH GE Corporate Intellectual Property Brown Boveri Strasse 7
5400 Baden
5400 Baden (CH)


(56)References cited: : 
EP-A1- 1 188 902
EP-A2- 1 074 696
EP-A2- 2 469 034
US-A- 5 413 458
EP-A1- 2 233 693
EP-A2- 1 726 785
US-A- 3 800 864
US-B1- 7 690 894
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    BACKGROUND OF THE INVENTION



    [0001] The subject matter disclosed herein relates to a turbine engine airfoil and, more particularly, to a turbine engine airfoil with a pin-bank alignment for film- cooling design.

    [0002] The current usage of pin-fins and film-cooling holes in gas turbine component cooling, especially in complex end-wall cooling configurations, is not provided so that film-cooling can be most effective for a given arbitrarily arranged pin-fin structure in a typically cast cavity of a gas path component. As such, it is difficult to place film-cooling holes on the hot surface of the gas path component due to film-cooling hole drilling restrictions for existing pin-fin arrays in the underlying coolant cavity. Thus, film-cooling holes are typically drilled at locations where they do not interfere with the pin-fin structure but do not necessarily provide for the most efficient film-cooling. Therefore, film effectiveness on the hot-surface is often non-optimal for given gasflow conditions.

    [0003] EP1726785 described an airfoil assembly including an airfoil extending away from a platform, with one or more cooling circuits formed through the platform. The cooling circuit includes a downwardly directed inlet receiving cooling air from below the platform which is then directed in a direction generally parallel to the outer surface of the platform and through exits formed therethrough. The cooling circuit may include a plurality of pedestals extending from an outer wall to an inner wall of the cooling circuit to increase the rigidity and the cooling function of the cooling circuit.

    [0004] US 5413458 describes a turbine vane for a gas turbine engine including a platform with a cavity along the trailing edge having a double feed arrangement for injecting cooling fluid into the cavity. The turbine vane includes a platform cavity having a first inlet located on the pressure side of the platform and forward of an attachment rail and a second inlet located on the suction side and forward of the attachment rail. The cavity includes a plurality of trip strips and a plurality of film cooling passages. The trip strips extend from the corners of the cavity and are angled to encourage cooling fluid to flow into the corners. The film cooling passages direct the exiting cooling fluid to form a film of cooling fluid over the platform flow surface.

    [0005] US 3800864 describes a fluid cooled element for partially defining a hot gas flow path within a gas turbine engine is provided with a cooling system incorporating a plurality of pin-fins or similar protuberances disposed upon a face of the wall bounding the hot gas passage. The protuberances can be arranged in greater densities per unit area in areas where heat concentrations exist in order to reduce temperature gradients. Furthermore, apertures for introducing and exhausting cooling fluid to and from the plenum may be sized and positioned to concentrate greater quantities of fluid upon areas of heat concentrations.

    [0006] EP 1074 696 describes a stator vane having a platform with internal cooling. The platform comprises a two-pass passage in flow communication with the exterior of the platform, the rearmost pass 170 discharging more than half the cooling fluid entering the two pass passage.

    [0007] EP 2 233 693 describes the features of the preamble of claim 1. It describes a cooling structure of a turbine airfoil cooling a turbine airfoil exposed to hot gas, using cooling air of a temperature lower than that of the hot gas. US 7 690 894 describes a turbine blade for use in a gas turbine engine having an internal serpentine flow cooling circuit with pin fins and trip strips to promote heat transfer for obtaining a thermally balanced blade sectional temperature distribution.

    [0008] EP 1 188 902 describes a component having a panel impacted by hot gases and cooled by impact-cooling jets, each of which is protected from a crosswise flow of cooling liquid by a projecting part.

    BRIEF DESCRIPTION OF THE INVENTION



    [0009] The invention resides in a hot gas path component and in a method of forming a hot gas path component as defined in the appended claims.

    [0010] These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0011] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:

    FIG. 1 is a schematic view of a hot gas path component; and

    FIG. 2 is a flow diagram illustrating a method of forming a hot gas path component.



    [0012] The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.

    DETAILED DESCRIPTION OF THE INVENTION



    [0013] With reference to FIG. 1, a hot gas path component 10 is provided. The hot gas path component 10 includes a body 20 having a surface 21. The body 20 is formed to define a cavity 30 therein. The cavity 30 employs coolant flow to cool the body 20 through a pin-fin bank 40 with coolant discharge to the surface 21 being permitted through film-cooling holes 50. The film-cooling holes 50 are defined on the surface 21 between individual pin-fins 55 of the pin-fin bank 40.

    [0014] In particular, the film-cooling holes 50 are defined on the surface 21 at a predefined film-hole centerline that provides the best cooling benefit, based on analysis, for topography of a given surface 21. Since optimal film-hole centerline locations would not be known, after the body 20 is formed (i.e., cast), it is necessary to provide space between the individual pin-fins 55 of the pin-fin bank 40 during the forming process.

    [0015] The film-cooling holes 50 can then be formed at a later time once the predefined film-hole centerline is ascertained in the space between the individual pin-fins 55. This later forming of the film-cooling holes 50 allows for tunable film cooling based on engine/test data without requiring, for example, a casting change and provides for relatively non-restricted film-cooling hole locations.

    [0016] The pin-fin bank 40 includes at least a first plurality of pin-fins 60 and a second plurality of pin-fins 70. The first plurality of pin-fins 60 and the second plurality of pin-fins 70 are each substantially and respectively aligned in parallel with a determined flow streamline 80, which describes an external gas flow velocity vector and which is known at a time the body 20 is formed. Any two individual pin-fins 55 of the first and/or the second pluralities of pin-fins 60, 70 are separated from one another by at least a gap, G. The gap, G, is determined as a function of at least a dimension of one or more of the film-cooling holes 50 in a direction substantially perpendicular to the determined flow streamline 80.

    [0017] The surface 21 includes a surface of an airfoil end wall structure of a gas turbine engine with the first plurality of pin-fins 60 being arranged proximate to an edge 90 of an airfoil footprint on an end wall and the second plurality of pin-fins 70 being arranged on a side of the first plurality of pin-fins 60 facing away from the edge 90. The pin-fin bank 40 may further include additional pluralities of pin-fins, such as third plurality of pin-fins 100 and fourth plurality of pin-fins 110. In addition, the pin-fin bank 40 may include a first set of pin-fins 120 and a second set of pin-fins 130, which are separated from one another by a predefined distance that is at least as large as the gap, G, along the determined flow streamline 80.

    [0018] The gap, G, is determined as a function of at least the dimension of one or more of the film-cooling holes 50 and at least one or more of the true position of the individual pin-fins 55 and film-cooling holes 50. The film-cooling holes 50 may have polygonal, trapezoidal, elliptical or other similar shapes. The dimensions of the one or more of the film-cooling holes 50 by which the gap, G, is determined may be a film-cooling hole diameter. Also, a film-cooling hole diffuser spread angle may be provided to cover pin-fin widths. This allows for potential film-cooling of any portion of the pin-fin bank 40 as needed without requiring, for example, a casting change.

    [0019] With reference to FIG. 2, a method of forming a hot gas path component 10 is provided. The method includes modeling 200 a shape of the hot gas path component 10, determining 210 the flow streamline 80 along the surface 21 of the modeled hot gas path component 10, and casting 220 the modeled hot gas path component 10. The casting 220 includes casting of the pin-fin bank 40 including first and second pluralities of pin-fins 60, 70, where the first plurality of pin-fins 60 and the second plurality of pin-fins 70 are each substantially and respectively aligned with the determined flow streamline 80. The casting 220 may include separating any two individual pin-fins 55 of the first and second pluralities of pin-fins 60, 70 by a gap, G, as a function of a film-cooling hole dimension where the film-cooling hole dimension may be a film-cooling hole diameter.

    [0020] Once the casting is complete, the alignment of the pin-fin bank 40 and the separation between individual pin-fins 55 allows for the tunable film cooling based on engine/test data without requiring, for example, casting changes and provides for relatively non-restricted film-cooling hole locations. As such, the method further includes machining 230 a film-cooling hole 50 at a predefined position wherein the machining may include, for example, machining the film-cooling hole 50 to have a polygonal, trapezoidal shape, an elliptical shape or another similar shape.

    [0021] 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, within the scope of the appended claims. 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.


    Claims

    1. A hot gas path component (10), comprising:

    a body (20) having a surface (21) and being formed to define a cavity (30), the cavity (30) employing coolant flow through a pin-fin bank (40) with coolant discharge through a plurality of film-cooling holes (50) defined on the surface (21),

    the pin-fin bank (40) including first and second pluralities of pin-fins (60, 70), the first plurality of pin-fins (60) and the second plurality of pin-fins (70) each being aligned in parallel with a determined flow streamline (80), and

    the plurality of film-cooling holes (50) defined on the surface (21) of the body (20) being between individual pin-fins of the pin-fin bank (40), wherein the distance between any two pin-fins (55) of the first and second pluralities of pin-fins (60, 70) is a function of a dimension of one or more of the plurality of film-cooling holes (50) in a direction perpendicular to the determined flow streamline (80),

    characterized in that

    the surface (21) includes a surface of an airfoil end wall structure of a gas turbine engine with the first plurality of pin-fins (60) being arranged proximate to an edge (90) of an airfoil footprint on an end wall of the airfoil end wall structure and the second plurality of pin-fins (70) being arranged on a side of the first plurality of pin-fins (60) facing away from the edge (90).


     
    2. The hot gas path component (10) according to claim 1, wherein the film-cooling hole (50) dimension is a film-cooling hole diameter.
     
    3. The hot gas path component (10) according to claim 1 or 2, wherein the film-cooling hole (50) has a polygonal shape.
     
    4. The hot gas path component (10) according to claim 1 or 2, wherein the film-cooling hole (50) has an elliptical shape.
     
    5. A gas turbine engine, comprising the hot gas path component of any of claims 1 to 4.
     
    6. A method of forming a hot gas path component according to claim 1, comprising:

    modeling the hot gas path component (200);

    determining a flow streamline (80) along a surface (21) of the modeled hot gas path component (210); and

    casting the modeled hot gas path component (210) with a pin-fin bank (40) including first and second pluralities of pin-fins (220), the first plurality of pin-fins (60) and the second plurality of pin-fins (70) each being aligned parallel with the determined flow streamline (80), wherein the distance between any two pin-fins (55) of the first and second pluralities of pin-fins (60, 70) is a function of a dimension of one or more film-cooling holes (50) in a direction perpendicular to the determined flow streamline (80); and

    machining film-cooling holes (50) on the surface (21) of the component (210) between individual pin-fins of the pin-fin bank (40);

    characterized in that

    the surface (21) includes a surface of an airfoil end wall structure of a gas turbine engine with the first plurality of pin-fins (60) being arranged proximate to an edge (90) of an airfoil footprint on an end wall of the airfoil end wall structure and the second plurality of pin-fins (70) being arranged on a side of the first plurality of pin-fins (60) facing away from the edge (90).


     
    7. The method according to claim 6, wherein dimension of the film-cooling hole (50) is a film-cooling hole diameter.
     
    8. The method according to claim 6 or 7, wherein the machining comprises machining the film-cooling hole (50) to have a polygonal shape.
     
    9. The method according to claim 6 or 7, wherein the machining comprises machining the film-cooling hole (50) to have an elliptical shape.
     


    Ansprüche

    1. Heißgasbeaufschlagter Bauteil (10), umfassend:

    einen Körper (20), der eine Fläche (21) aufweist und derart gebildet ist, um einen Hohlraum (30) zu definieren, wobei der Hohlraum (30) einen Kühlmittelfluss durch eine Pin-Fin-Platte (40) mit einem Kühlmittelablauf durch eine Vielzahl von filmkühlenden Löchern (50), die an der Fläche (21) definiert ist, einsetzt,

    wobei die Pin-Fin-Platte (40) erste und zweite Vielzahlen von Pin-Fins (60, 70) einschließt, wobei die erste Vielzahl von Pin-Fins (60) und die zweite Vielzahl von Pin-Fins (70) jeweils parallel mit einer festgestellten Laminarströmung (80) ausgerichtet ist, und

    wobei die Vielzahl von filmkühlenden Löchern (50), die an der Fläche (21) des Körpers (20) definiert ist, zwischen einzelnen Pin-Fins der Pin-Fin-Platte (40) vorhanden ist, wobei der Abstand zwischen beliebigen zwei Pin-Fins (55) der ersten und der zweiten Vielzahlen von Pin-Fins (60, 70) eine Funktion einer Abmessung der einen oder der mehreren Vielzahlen von filmkühlenden Löchern (50) in einer Richtung senkrecht zu der festgestellten Laminarströmung (80) ist,

    dadurch gekennzeichnet, dass

    die Fläche (21) eine Fläche eines Abschlusswand-Strukturprofils eines Gasturbinenmotors einschließt, wobei die erste Vielzahl von Pin-Fins (60) benachbart einer Kante (90) einer Profilstandfläche an einer Abschlusswand des Abschlusswand-Strukturprofils angeordnet ist, und die zweite Vielzahl von Pin-Fins (70) an einer Seite der ersten Vielzahl von Pin-Fins (60), die von der Kante (90) weggerichtet ist, angeordnet ist.


     
    2. Heißgasbeaufschlagter Bauteil (10) nach Anspruch 1, wobei die Abmessung des filmkühlenden Lochs (50) ein Durchmesser des filmkühlenden Lochs ist.
     
    3. Heißgasbeaufschlagter Bauteil (10) nach Anspruch 1 oder 2, wobei das filmkühlende Loch (50) eine mehreckige Gestalt aufweist.
     
    4. Heißgasbeaufschlagter Bauteil (10) nach Anspruch 1 oder 2, wobei das filmkühlende Loch (50) eine elliptische Gestalt aufweist.
     
    5. Gasturbinenmotor, umfassend das heißgasbeaufschlagte Bauteil (10) nach einem der Ansprüche 1 bis 4.
     
    6. Verfahren zum Formen eines heißgasbeaufschlagten Bauteils (10) nach Anspruch 1, umfassend:

    das Modellieren des heißgasbeaufschlagten Bauteils (200);

    das Feststellen einer Laminarströmung (80) entlang einer Fläche (21) des modellierten, heißgasbeaufschlagten Bauteils (210); und

    das Gießen des heißgasbeaufschlagten Bauteils (210) mit einer Pin-Fin-Platte (40), einschließlich der ersten und der zweiten Vielzahlen von Pin-Fins (220), wobei die erste Vielzahl von Pin-Fins (60) und die zweite Vielzahl von Pin-Fins (70) jeweils parallel mit der festgestellten Laminarströmung (80) ausgerichtet ist, wobei der Abstand zwischen beliebigen zwei Pin-Fins (55) der ersten und der zweiten Vielzahlen von Pin-Fins (60, 70) eine Funktion einer Abmessung des einen oder der mehreren filmkühlenden Löcher (50) in einer Richtung senkrecht zu der festgestellten Laminarströmung (80) ist; und

    das maschinelle Bearbeiten der filmkühlenden Löcher (50) an der Fläche (21) des Bauteils (210) zwischen einzelnen Pin-Fins der Pin-Fin-Platte (40);

    dadurch gekennzeichnet, dass

    die Fläche (21) eine Fläche eines Abschlusswand-Strukturprofils eines Gasturbinenmotors einschließt, wobei die erste Vielzahl von Pin-Fins (60) benachbart einer Kante (90) einer Profilstandfläche an einer Abschlusswand des Abschlusswand-Strukturprofils angeordnet ist, und die zweite Vielzahl von Pin-Fins (70) an einer Seite der ersten Vielzahl von Pin-Fins (60), die von der Kante (90) weggerichtet ist, angeordnet ist.


     
    7. Verfahren nach Anspruch 6, wobei die Abmessung des filmkühlenden Lochs (50) ein Durchmesser des filmkühlenden Lochs ist.
     
    8. Verfahren nach Anspruch 6 oder 7, wobei die maschinelle Bearbeitung die maschinelle Bearbeitung des filmkühlenden Lochs (50) umfasst, um eine mehreckige Gestalt aufzuweisen.
     
    9. Verfahren nach Anspruch 6 oder 7, wobei die maschinelle Bearbeitung die maschinelle Bearbeitung des filmkühlenden Lochs (50) umfasst, um eine elliptische Gestalt aufzuweisen.
     


    Revendications

    1. Composant de trajet de gaz chaud (10) comprenant :

    un corps (20) ayant une surface (21) et formé pour définir une cavité (30), la cavité (30) employant un écoulement de réfrigérant à travers un banc d'aiguilles (40) avec une décharge de réfrigérant à travers une pluralité de trous de refroidissement de film (50) définis sur la surface (21),

    le banc d'aiguilles (40) incluant une première et une seconde pluralité d'aiguilles (60, 70), la première pluralité d'aiguilles (60) et la seconde pluralité d'aiguilles (70) étant alignées chacune en parallèle avec une ligne aérodynamique d'écoulement déterminée (80), et

    la pluralité de trous de refroidissement de film (50) définis sur la surface (21) du corps (20) se trouvant entre des aiguilles individuelles du banc d'aiguilles (40), dans lequel la distance entre deux aiguilles quelconques (55) de la première et de la seconde pluralité d'aiguilles (60, 70) est fonction d'une dimension d'un ou plusieurs de la pluralité de trous de refroidissement de film (50) dans une direction perpendiculaire à la ligne aérodynamique d'écoulement déterminée (80),

    caractérisé en ce que

    la surface (21) inclut une surface d'une structure de paroi d'extrémité de profil aérodynamique d'un moteur à turbine à gaz avec la première pluralité d'aiguilles (60) qui est agencée à proximité d'un bord (90) d'une empreinte de profil aérodynamique sur une paroi d'extrémité de la structure de paroi d'extrémité de profil aérodynamique et la seconde pluralité d'aiguilles (70) qui est agencée sur un côté de la première pluralité d'aiguilles (60) opposée au bord (90).


     
    2. Composant de trajet de gaz chaud (10) selon la revendication 1, dans lequel la dimension de trou de refroidissement de film (50) est un diamètre de trou de refroidissement de film.
     
    3. Composant de trajet de gaz chaud (10) selon la revendication 1 ou 2, dans lequel le trou de refroidissement de film (50) a une forme polygonale.
     
    4. Composant de trajet de gaz chaud (10) selon la revendication 1 ou 2, dans lequel le trou de refroidissement de film (50) a une forme elliptique.
     
    5. Moteur à turbine à gaz comprenant le composant de trajet de gaz d'échappement selon l'une quelconque des revendications 1 à 4.
     
    6. Procédé de formation d'un composant de trajet de gaz chaud (10) selon la revendication 1, comprenant :

    la modélisation du composant de trajet de gaz chaud (200) ;

    la détermination d'une ligne aérodynamique d'écoulement (80) le long d'une surface (21) du composant de trajet de gaz chaud modélisé (210) ; et

    la coulée du composant de trajet de gaz chaud modélisé (210) avec un banc d'aiguilles (40) incluant une première et une seconde pluralité d'aiguilles (220), la première pluralité d'aiguilles (60) et la seconde pluralité d'aiguilles (70) étant chacune alignées parallèlement à la ligne aérodynamique d'écoulement déterminée (80), dans lequel la distance entre deux aiguilles quelconques (55) de la première et de la seconde pluralité d'aiguilles (60, 70) est fonction d'une dimension d'un ou plusieurs trous de refroidissement de film (50) dans une direction perpendiculaire à la ligne aérodynamique d'écoulement déterminée (80) ; et

    l'usinage de trous de refroidissement de film (50) sur la surface (21) du composant (210) entre des aiguilles individuelles du banc d'aiguilles (40) ;

    caractérisé en ce que

    la surface (21) inclut une surface d'une structure de paroi d'extrémité de profil aérodynamique d'un moteur à turbine à gaz avec la première pluralité d'aiguilles (60) qui est agencée à proximité d'un bord (90) d'une empreinte de profil aérodynamique sur une paroi d'extrémité de la structure de paroi d'extrémité de profil aérodynamique et la seconde pluralité d'aiguilles (70) qui est agencée sur un côté de la première pluralité d'aiguilles (60) opposée au bord (90).


     
    7. Procédé selon la revendication 6, dans lequel la dimension du trou de refroidissement de film (50) est un diamètre de trou de refroidissement de film.
     
    8. Procédé selon la revendication 6 ou 7, dans lequel l'usinage comprend l'usinage du trou de refroidissement de film (50) en sorte qu'il ait une forme polygonale.
     
    9. Procédé selon la revendication 6 ou 7, dans lequel l'usinage comprend l'usinage du trou de refroidissement de film (50) en sorte qu'il ait une forme elliptique.
     




    Drawing











    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description