EP3762587B1 - Airfoil for a turbine blade - Google Patents

Airfoil for a turbine blade Download PDF

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Publication number
EP3762587B1
EP3762587B1 EP19723730.8A EP19723730A EP3762587B1 EP 3762587 B1 EP3762587 B1 EP 3762587B1 EP 19723730 A EP19723730 A EP 19723730A EP 3762587 B1 EP3762587 B1 EP 3762587B1
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EP
European Patent Office
Prior art keywords
aerofoil
cooling holes
height
series
blade
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EP19723730.8A
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German (de)
French (fr)
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EP3762587A1 (en
Inventor
Fathi Ahmad
Daniela Koch
Marco Schüler
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Siemens Energy Global GmbH and Co KG
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Siemens Energy Global GmbH and Co KG
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Publication of EP3762587A1 publication Critical patent/EP3762587A1/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/12—Blades
    • F01D5/14—Form or construction
    • F01D5/18—Hollow blades, i.e. blades with cooling or heating channels or cavities; Heating, heat-insulating or cooling means on blades
    • F01D5/186—Film cooling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2220/00—Application
    • F05D2220/30—Application in turbines
    • F05D2220/32—Application in turbines in gas turbines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2240/00—Components
    • F05D2240/20—Rotors
    • F05D2240/30—Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor
    • F05D2240/303—Characteristics of rotor blades, i.e. of any element transforming dynamic fluid energy to or from rotational energy and being attached to a rotor related to the leading edge of a rotor blade
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2260/00—Function
    • F05D2260/20—Heat transfer, e.g. cooling
    • F05D2260/202—Heat transfer, e.g. cooling by film cooling

Definitions

  • the invention relates to a blade for a turbine blade, comprising a leading edge against which a hot gas can flow, from which a suction side wall and a pressure side wall extend to a trailing edge of the blade, the blade extending in a transverse direction thereto from a root end with a blade height of 0 % to a tip end with an airfoil height of 100%, with at least two rows of cooling holes arranged along the leading edge and having a first distance from one another to be measured perpendicular to the leading edge.
  • Such a turbine blade is, for example, from EP 2 154 333 A2 famous.
  • the cooling holes arranged in the leading edge serve to produce a cooling protective film over the leading edge during operation of a gas turbine equipped therewith, in order to counteract the incoming flow of hot gas.
  • the cooling holes are therefore also referred to as film cooling holes, which are also known in English as “shower head film cooling holes” due to their dense arrangement.
  • the airfoil divides the incoming hot gas flow at the leading edge into two partial flows, one of which flows along the suction side of the airfoil and the other part along the pressure side.
  • the location of the flow distribution on the blade profile is called the stagnation point, since in the idealized sense no cross flow occurs there.
  • film cooling holes are arranged on both sides of the front edge or the previously determined stagnation line, in order to prevent the hot gas flow impinging there from coming into too close contact with the component wall.
  • the invention is based on the object of providing an airfoil for a turbine blade which is designed in the best possible way for different operating conditions of a gas turbine, in particular in order to achieve adequate cooling with the longest possible service life of the airfoil when using an acceptable amount of coolant .
  • This object is achieved with a blade of the type mentioned at the outset in that the at least two rows of cooling holes are arranged at least partially along the leading edge on a wavy line.
  • the wavy line is slightly curved, without changing the sign of its curvature, such that the cooling holes of each of the at least two rows are arranged further downstream at both the root end and the tip end of the airfoil than the cooling holes of the corresponding row at half-height of the airfoil.
  • the invention is based on the finding that the actual hot gas flow direction depends on the design of the Airfoil used flow direction can differ on the one hand due to different operating modes of the gas turbine. The deviations can occur due to a change in the load output compared to the nominal load.
  • the stagnation point of a blade profile in the area of the leading edge can oscillate due to flow effects which are caused by a guide blade arranged upstream of the moving blade. The oscillation of the stagnation point of a blade profile leads to a locally increased surface temperature of the blade airfoil, which can be counteracted effectively with the invention.
  • the invention now proposes providing at least two rows of cooling holes in the area of the leading edge, which are at least partially arranged on a curved wavy line.
  • the cooling holes are shifted towards the pressure side or the suction side in relation to the oscillating stagnation point of the relevant blade profile.
  • an area is determined for each blade profile in which the stagnation point can occur.
  • Each of these areas is defined by two end points, from which an average stagnation point can then be determined.
  • the two cooling holes are then positioned in such a way that the best possible cooling is achieved. This allows the cooling effect to be optimized locally.
  • the amount of coolant required for cooling can be reduced. The reduced consumption of coolant contributes to the increase in efficiency of the gas turbine during operation.
  • each of the at least two rows are located near the root end and near the tip end of the airfoil further downstream than the cooling holes of the corresponding half-airfoil row.
  • the wavy line then extends between these points without one Changing the sign of its curvature so that it is only slightly curved.
  • this variant represents a more favorable cooling configuration, especially for guide vanes, since with these vanes the stagnation point shift occurs more at the ends of the airfoil than in its center and also towards the suction side.
  • the maximum displacement of the relevant cooling holes near the ends of the airfoil is then only a few millimeters, in particular 2 mm, towards the suction side, compared to the position of the cooling holes of the same row at half the airfoil height, ie at 50% of the airfoil height.
  • the first distance between the at least two rows of cooling holes varies along the leading edge, so that the first distance is different for some blade heights.
  • the local cooling capacity of the turbine blade in the area of the leading edge can be adapted locally to the individual temperature load.
  • a blade profile can be determined by examining a cross section, which profile is known to have the shape of a curved drop.
  • Each blade profile therefore has a nose radius in the area of the leading edge, with the blade profiles having a first distance between the at least two rows at the level of cooling holes, the size of which is in the range between 0.4 times and 0.7 times the associated nose radius located.
  • the effectiveness of the cooling depends on the distance between the cooling holes of different rows and the curvature of the leading edge, the so-called nose radius, as well as the length of the camberline, the number of blades and the turning of the blade profile. It was then found that a particularly efficient cooling of the leading edge region can be achieved if the first distance between the cooling holes of different rows that are at the same blade height lies within the claimed interval.
  • the first distance is smallest at half the height of the airfoil and increases towards the two ends.
  • the increase is particularly moderate.
  • each cooling hole preferably has a throttle cross section that adjusts the coolant flow, the throttle cross sections of some cooling holes being of different sizes.
  • the throttle cross sections of the cooling holes in the region of half the blade height are particularly preferably larger than the throttle cross section of the cooling holes in the region further away from half the blade height.
  • This configuration is based on the finding that at half the blade height and in the regions immediately adjacent thereto, there is a somewhat greater cooling requirement than in those regions of the leading edge which are further away from half the blade height.
  • the configuration in which the at least two rows of cooling holes are arranged on both sides of a central stagnation point line of the incoming hot gas flow is particularly preferred.
  • the hot gas flow is divided into a part flowing to the pressure side and a part flowing to the suction side, which is diverted to both sides, so that the component wall underneath is particularly efficiently protected from the high temperatures of the hot gas due to the arrangement of the cooling holes on both sides.
  • a further but shortened row of essentially evenly spaced cooling holes is provided on the pressure side in addition to the at least two rows, with the length of the further row between 50% and 60% of the airfoil height and the further row of cooling holes is arranged substantially centrally between the two ends of the airfoil.
  • the further row is arranged essentially centrally as long as it is divided by half the airfoil height into two parts, the shorter part of which is not shorter than 1/3 of the length of the further row.
  • the length of the further row of cooling holes is recorded in the same direction as the airfoil height.
  • the airfoil is preferably part of a turbine blade, in particular a turbine guide blade of a stationary gas turbine.
  • FIG 1 a turbine rotor blade 10 is shown in a perspective view.
  • the turbine blade 10 successively comprises an essentially fir-tree-shaped blade root 12, which is adjoined by a hot-gas platform 14 as the end wall.
  • an airfoil 16 On its surface facing the hot gas S, an airfoil 16 according to a first example is arranged.
  • the airfoil 16 is known to include a leading edge 18 and a trailing edge 20 between which a suction sidewall 17 and a pressure sidewall 19 extend. In a direction transverse thereto, the airfoil 16 extends from a root end 21 at 0% airfoil height to a tip end 23 at 100% airfoil height.
  • Two rows R 1 , R 2 of cooling holes 22 are arranged along the leading edge 18 .
  • the two rows R 1 , R 2 run along a wavy line with a plurality of wave troughs and wave crests and are simultaneously arranged on both sides of a central stagnation point line 24
  • a second example is in figure 2 shown.
  • a region is straight, followed by a bulbous section.
  • the two rows R 1 , R 2 of cooling holes 22 are arranged in the first, radially inner area in such a way that they are arranged parallel to the leading edge 18 on both sides thereof.
  • This first range B 1 extends between 0% and about 40% airfoil height.
  • a second area B 2 is provided radially on the outside. This ends at an airfoil height of about 75%.
  • the cooling holes 22 of both rows R 1 , R 2 move further towards the pressure side with increasing height until they have reached the maximum displacement away from the leading edge 18 at about 75% airfoil height.
  • the cooling holes 22 of the two rows R 1 , R 2 shift back again in the direction of the front edge 18 .
  • cooling holes 22 are shown only schematically as circles, with their throttle cross sections being shown schematically by circles of different sizes.
  • the cooling holes 22 can be film cooling holes that have a diffuser-like opening. Its diffuser can even be designed with a profile.
  • a distance A between the cooling holes 22 to be measured transversely on the surface of the airfoil 16 can also be of different sizes at different airfoil heights.
  • FIG. 12 also shows, as a blade profile 28, the cross section through the airfoil 16 of the first example according to FIG figure 1 .
  • the blade profile center line is provided with reference number 30 .
  • the foremost arranged point of the blade profile center line 30 defines the leading edge 18.
  • the stagnation point 25 can be slightly shifted away from the leading edge 18 towards the pressure side 19 or towards the suction side 17.
  • the (middle) stagnation points 25 of each blade profile section which can be determined at any blade height, together form the stagnation point line 24.
  • the nose radius is denoted by R.
  • FIG 4 An embodiment of the invention is in figure 4 shown. It shows a perspective view of a turbine blade configured as a guide blade, with the blade root 12 comprising two hook-shaped rails for fastening the blade to a blade carrier (not shown in any more detail).
  • a platform 14 is provided at both the root end 21 and the tip end 23 of the airfoil to limit the flow path.
  • the airfoil 16 extends along its airfoil height.
  • the at least two rows R 1 , R 2 of cooling holes 18 are also arranged analogously: starting with the cooling holes at half the height of the airfoil, within each row R 1 , R 2 the cooling holes arranged with decreasing spacing towards the platforms 14 are arranged further on the suction side .
  • the stagnation point line 24 is slightly curved without changing the sign of its curvature.
  • a further but shortened row of substantially evenly spaced cooling holes 18 is provided on the pressure side next to the two rows R 1 , R 2 .
  • This further row R 3 is according to this embodiment in the middle between the two platforms 14 and the two ends 21, 23 and extends over a length of only 55% of the blade height. It is therefore shorter than the two rows R 1 , R 2 .
  • the invention relates to an airfoil 16 for a turbine blade 10, comprising a leading edge 18 against which a hot gas S can flow, from which a suction sidewall 17 and a pressure sidewall 19 extend to a trailing edge 20 of the airfoil 16, the airfoil 16 being in a transverse direction thereto extending from a root end 21 with an airfoil height of 0% to a tip end 23 with an airfoil height of 100%, with two rows R 1 , R 2 of cooling holes 22 arranged along the leading edge, the mutually perpendicular to the leading edge 18 to be detected have first distance A.
  • the two rows R 1 , R 2 of cooling holes 22 be arranged at least partially along the leading edge 18 on a wavy line.
  • the wavy line 24 is slightly curved without changing the sign of its curvature such that the cooling holes 18 of each of the at least two rows (Ri, R2) are arranged further on the suction side than the cooling holes at both the root end 21 and the tip end 23 of the airfoil 18 of the corresponding row (Ri, R2) at half blade height.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)

Description

Die Erfindung betrifft ein Schaufelblatt für eine Turbinenschaufel, umfassend eine von einem Heißgas anströmbare Vorderkante, von der aus sich eine Saugseitenwand und eine Druckseitenwand zu einer Hinterkante des Schaufelblatts erstrecken, wobei das Schaufelblatt in einer Querrichtung dazu sich von einem fußseitigen Ende mit einer Schaufelblatthöhe von 0% zu einem spitzenseitigem Ende mit einer Schaufelblatthöhe von 100% erstreckt, mit zumindest zwei längs der Vorderkante angeordneten Reihen von Kühllöchern, die zueinander einen senkrecht zur Vorderkante zu erfassenden ersten Abstand aufweisen.The invention relates to a blade for a turbine blade, comprising a leading edge against which a hot gas can flow, from which a suction side wall and a pressure side wall extend to a trailing edge of the blade, the blade extending in a transverse direction thereto from a root end with a blade height of 0 % to a tip end with an airfoil height of 100%, with at least two rows of cooling holes arranged along the leading edge and having a first distance from one another to be measured perpendicular to the leading edge.

Eine derartige Turbinenschaufel ist beispielsweise aus der EP 2 154 333 A2 bekannt. Die in der Vorderkante angeordneten Kühllöcher dienen während des Betriebs einer damit ausgestatteten Gasturbine zur Erzeugung eines kühlenden Schutzfilmes über der Vorderkante, um der ankommenden Heißgasströmung entgegenwirken. Die Kühllöcher werden deswegen auch als Filmkühllöcher bezeichnet, die im Englischen aufgrund ihrer dichten Anordnung zudem auch als "Shower Head Film Cooling Holes" bekannt sind. Zugleich teilt das Schaufelblatt die anströmende Heißgasströmung an der Vorderkante in zwei Teilströme auf, von denen der eine Teilstrom entlang der Saugseite des Schaufelblatts entlang strömt und der andere Teil entlang der Druckseite. Der Ort der Strömungsaufteilung am Schaufelprofil wird dabei Stagnationspunkt genannt, da im idealisierten Sinne dort keine Querströmung auftritt. Aus diesem Grund sind im Stand der Technik beidseits der Vorderkante bzw. der vorab ermittelten Stagnationslinie Filmkühllöcher angeordnet, um die dort auftreffende Heißgasströmung nicht in zu engen Kontakt mit der Bauteilwand gelangen zu lassen.Such a turbine blade is, for example, from EP 2 154 333 A2 famous. The cooling holes arranged in the leading edge serve to produce a cooling protective film over the leading edge during operation of a gas turbine equipped therewith, in order to counteract the incoming flow of hot gas. The cooling holes are therefore also referred to as film cooling holes, which are also known in English as "shower head film cooling holes" due to their dense arrangement. At the same time, the airfoil divides the incoming hot gas flow at the leading edge into two partial flows, one of which flows along the suction side of the airfoil and the other part along the pressure side. The location of the flow distribution on the blade profile is called the stagnation point, since in the idealized sense no cross flow occurs there. For this reason, in the prior art, film cooling holes are arranged on both sides of the front edge or the previously determined stagnation line, in order to prevent the hot gas flow impinging there from coming into too close contact with the component wall.

Nachteilig ist jedoch, dass der Stagnationspunkt eines Schaufelprofils bzw. die Stagnationslinie eines Schaufelblatts von unterschiedlichen Einflussfaktoren abhängig sein kann, so dass der Bedarf besteht, die Turbinenschaufel und dessen Schaufelblatt sowie dessen Vorderkantenkühlung an die unterschiedlichen Betriebsbedingungen bestmöglich anzupassen.The disadvantage, however, is that the stagnation point of a blade profile or the stagnation line of a blade leaf can depend on different influencing factors, so that there is a need to adapt the turbine blade and its blade leaf as well as its leading edge cooling to the different operating conditions as best as possible.

So lehrt die US 2016/0010463 A1 bei einer Verschiebung der Stagnationslinie, auf der Druckseite von Laufschaufeln eine zusätzliche Halb-Reihe von Filmkühllöcher auf der radial äußeren Hälfte des Schaufelblatts anzuordnen. Die zusätzlichen Filmkühllöcher erhöhen jedoch den Verbrauch an Kühlluft, was sich negativ auf den Wirkungsgrad einer damit ausgestatteten Turbine auswirkt.That's how she teaches US 2016/0010463 A1 with a stagnation line shift, on the pressure side of blades to place an additional half-row of film cooling holes on the radially outer half of the airfoil. However, the additional film cooling holes increase the consumption of cooling air, which has a negative effect on the efficiency of a turbine equipped with them.

Nach der EP 3 043 026 A2 kann eine angepasste Kühlung auch dadurch erreicht werden, dass bei einer vorab ermittelten Verschiebung der Staupunktlinie nicht die Position, sondern lediglich die Neigung einiger Anströmkanten-Filmkühllöcher so gewählt wird, dass diese zur erwarteten lokalen Heißgasströmung nicht in entgegengesetzter Richtung die Kühlluft ausblasen, sondern in gleicher Richtung.After EP 3 043 026 A2 Adapted cooling can also be achieved in that, with a previously determined shift in the stagnation point line, not the position but only the inclination of some leading edge film cooling holes is selected in such a way that they do not blow out the cooling air in the opposite direction to the expected local hot gas flow, but in the same direction Direction.

Ausgehend vom zuvor beschriebenen Stand der Technik liegt der Erfindung die Aufgabe zugrunde ein Schaufelblatt für eine Turbinenschaufel bereitzustellen, welches für unterschiedliche Betriebsbedingungen einer Gasturbine bestmöglich gestaltet ist, insbesondere um bei Einsatz einer vertretbaren Menge an Kühlmittel eine hinreichende Kühlung mit möglichst hoher Lebensdauer des Schaufelblatts zu erzielen.Proceeding from the prior art described above, the invention is based on the object of providing an airfoil for a turbine blade which is designed in the best possible way for different operating conditions of a gas turbine, in particular in order to achieve adequate cooling with the longest possible service life of the airfoil when using an acceptable amount of coolant .

Diese Aufgabe wird mit einem Schaufelblatt der eingangs genannten Art dadurch gelöst, dass die zumindest zwei Reihen von Kühllöchern zumindest teilweise längs der Vorderkante auf einer Wellenlinie angeordnet sind. Die Wellenlinie ist ohne eine Änderung des Vorzeichens ihrer Krümmung derart geringfügig gekrümmt, dass die Kühllöcher jeder der zumindest zwei Reihen sowohl an dem fußseitigen Ende und an dem spitzenseitigen Ende des Schaufelblatts weiter saugseitig angeordnet sind als die Kühllöcher der entsprechenden Reihe auf halber Schaufelblatthöhe.This object is achieved with a blade of the type mentioned at the outset in that the at least two rows of cooling holes are arranged at least partially along the leading edge on a wavy line. The wavy line is slightly curved, without changing the sign of its curvature, such that the cooling holes of each of the at least two rows are arranged further downstream at both the root end and the tip end of the airfoil than the cooling holes of the corresponding row at half-height of the airfoil.

Der Erfindung liegt die Erkenntnis zugrunde, dass die tatsächliche Heißgasströmungsrichtung von der zur Auslegung des Schaufelblatts herangezogenen Strömungsrichtung abweichen kann einerseits aufgrund unterschiedlicher Betriebsweisen der Gasturbine. Die Abweichungen können aufgrund einer zur Nennlast veränderten Lastabgabe auftreten. Andererseits wurde erkannt, dass insbesondere bei Laufschaufeln der Stagnationspunkt eines Schaufelprofils im Bereich der Vorderkante oszillieren kann aufgrund von Strömungseffekten, die von einer stromauf der Laufschaufel angeordneten Leitschaufel hervorgerufen werden. Die Oszillation des Stagnationspunktes eines Schaufelprofils führt zu lokal erhöhter Oberflächentemperatur des Schaufelblattes, dem mit der Erfindung wirksam begegnet werden kann.The invention is based on the finding that the actual hot gas flow direction depends on the design of the Airfoil used flow direction can differ on the one hand due to different operating modes of the gas turbine. The deviations can occur due to a change in the load output compared to the nominal load. On the other hand, it was recognized that, particularly in the case of moving blades, the stagnation point of a blade profile in the area of the leading edge can oscillate due to flow effects which are caused by a guide blade arranged upstream of the moving blade. The oscillation of the stagnation point of a blade profile leads to a locally increased surface temperature of the blade airfoil, which can be counteracted effectively with the invention.

Um beiden Effekten entgegenzuwirken wird mit der Erfindung nunmehr vorgeschlagen, zumindest zwei Reihen von Kühllöchern im Bereich der Vorderkante vorzusehen, die zumindest teilweise auf einer gekrümmten Wellenlinie angeordnet sind. Die Kühllöcher sind zur Druckseite bzw. Saugseite hin verschoben, bezogen auf den oszillierenden Stagnationspunkt des betreffenden Schaufelprofils. Während der Designphase wird für jedes Schaufelprofil ein Bereich ermittelt, in dem der Stagnationspunkt auftreten, kann. Jeder dieser Bereiche ist durch zwei Endpunkte definiert, aus denen dann ein mittlerer Staupunkt ermittelbar ist. Anschließend werden die beiden Kühllöcher so positioniert, dass eine bestmögliche Kühlung erreicht wird. Hiermit lässt sich der Kühleffekt lokal optimieren. Durch die Verwendung von lediglich zwei Kühlreihen anstelle von üblicherweise drei oder mehr vollständigen Kühlreihen kann zudem die zur Kühlung erforderliche Menge an Kühlmittel reduziert werden. Der reduzierte Verbrauch an Kühlmittel trägt während des Betriebs der Gasturbine zu dessen Wirkungsgradsteigerung bei.In order to counteract both effects, the invention now proposes providing at least two rows of cooling holes in the area of the leading edge, which are at least partially arranged on a curved wavy line. The cooling holes are shifted towards the pressure side or the suction side in relation to the oscillating stagnation point of the relevant blade profile. During the design phase, an area is determined for each blade profile in which the stagnation point can occur. Each of these areas is defined by two end points, from which an average stagnation point can then be determined. The two cooling holes are then positioned in such a way that the best possible cooling is achieved. This allows the cooling effect to be optimized locally. In addition, by using only two refrigeration banks instead of typically three or more full refrigeration banks, the amount of coolant required for cooling can be reduced. The reduced consumption of coolant contributes to the increase in efficiency of the gas turbine during operation.

Die Kühllöcher jeder der zumindest zwei Reihen sind nahe dem fußseitigen Ende und nahe dem spitzenseitigen Ende des Schaufelblatts weiter saugseitig angeordnet als die Kühllöcher der entsprechenden Reihe auf halber Schaufelblatthöhe. Die Wellenlinie erstreckt sich dann zwischen diesen Punkten ohne eine Änderung des Vorzeichens ihrer Krümmung, sodass sie lediglich geringfügig gekrümmt ist. Eingehende Untersuchungen zeigten, dass diese Variante insbesondere für Leitschaufeln eine günstigere Kühlkonfiguration darstellt, da bei diesen Schaufeln die Staupunktverschiebung vielmehr an den Enden des Schaufelblatts als in dessen Mitte und zudem zur Saugseite hin auftritt. Die maximale Verschiebung der betreffenden Kühllöcher nahe der Enden des Schaufelblatts beträgt dann lediglich einige Millimeter, insbesondere 2 mm, zur Saugseite hin, verglichen mit der Position der Kühllöcher der gleichen Reihe auf halber Schaufelblatthöhe, d.h. bei 50 % der Schaufelblatthöhe.The cooling holes of each of the at least two rows are located near the root end and near the tip end of the airfoil further downstream than the cooling holes of the corresponding half-airfoil row. The wavy line then extends between these points without one Changing the sign of its curvature so that it is only slightly curved. Detailed investigations showed that this variant represents a more favorable cooling configuration, especially for guide vanes, since with these vanes the stagnation point shift occurs more at the ends of the airfoil than in its center and also towards the suction side. The maximum displacement of the relevant cooling holes near the ends of the airfoil is then only a few millimeters, in particular 2 mm, towards the suction side, compared to the position of the cooling holes of the same row at half the airfoil height, ie at 50% of the airfoil height.

In den Unteransprüchen sind weitere vorteilhafte Maßnahmen aufgelistet, die beliebig miteinander kombiniert werden können. Damit lassen sich weitere Vorteile erzielen.Further advantageous measures are listed in the dependent claims, which can be combined with one another as desired. This allows further advantages to be achieved.

Ergänzend zu den vorgenannten Ausgestaltungen ist es von besonderem Vorteil, wenn der erste Abstand zwischen den zumindest zwei Reihen von Kühllöchern längs der Vorderkante variiert, so dass der erste Abstand für einige Schaufelblatthöhen unterschiedlich groß ist. Mit dieser Maßnahme kann das lokale Kühlvermögen der Turbinenschaufel im Bereich der Vorderkante an die individuelle Temperaturbelastung lokal angepasst werden.In addition to the aforementioned configurations, it is particularly advantageous if the first distance between the at least two rows of cooling holes varies along the leading edge, so that the first distance is different for some blade heights. With this measure, the local cooling capacity of the turbine blade in the area of the leading edge can be adapted locally to the individual temperature load.

Selbstverständlich ist für jede Schaufelblatthöhe durch eine Querschnittsbetrachtung ein Schaufelprofil ermittelbar, welches bekanntermaßen die Form eines gewölbten Tropfens aufweist. Jedes Schaufelprofil weist mithin im Bereich der Vorderkante einen Nasenradius auf, wobei die Schaufelprofile auf Höhe von Kühllöchern einen ersten Abstand zwischen den zumindest zwei Reihen aufweisen, dessen Größe im Bereich zwischen dem 0,4-fachen und dem 0,7-fachen des zugehörigen Nasenradius liegt. Eingehende Untersuchungen haben herausgefunden, dass die Wirksamkeit der Kühlung vom Abstand der Kühllöcher unterschiedlicher Reihen und von der Krümmung der Vorderkante, dem sogenannten Nasenradius sowie der Länge der Camberline, der Schaufelzahl und dem Turning des Schaufelprofils abhängt. Es wurde sodann festgestellt, dass eine besonders effiziente Kühlung des Vorderkantenbereichs erzielt werden kann, wenn der erste Abstand zwischen den auf gleicher Schaufelblatthöhe liegenden Kühllöchern unterschiedlicher Reihen im beanspruchten Intervall liegt.Of course, for each blade height, a blade profile can be determined by examining a cross section, which profile is known to have the shape of a curved drop. Each blade profile therefore has a nose radius in the area of the leading edge, with the blade profiles having a first distance between the at least two rows at the level of cooling holes, the size of which is in the range between 0.4 times and 0.7 times the associated nose radius located. Extensive investigations have found that the effectiveness of the cooling depends on the distance between the cooling holes of different rows and the curvature of the leading edge, the so-called nose radius, as well as the length of the camberline, the number of blades and the turning of the blade profile. It was then found that a particularly efficient cooling of the leading edge region can be achieved if the first distance between the cooling holes of different rows that are at the same blade height lies within the claimed interval.

Gemäß einer weiteren vorteilhaften Ausgestaltung ist der erste Abstand auf halber Schaufelblatthöhe am kleinsten und nimmt zu den beiden Enden hin zu. Die Zunahme ist insbesondere moderat.According to a further advantageous embodiment, the first distance is smallest at half the height of the airfoil and increases towards the two ends. The increase is particularly moderate.

Um die Kühlung der Vorderkante für unterschiedliche Schaufelblatthöhen weiter bedarfsgemäß anzupassen, weist bevorzugtermaßen jedes Kühlloch einen den Kühlmitteldurchfluss einstellenden Drosselquerschnitt auf, wobei die Drosselquerschnitte einiger Kühllöcher unterschiedlich groß sind. Besonders bevorzugt sind die Drosselquerschnitte der Kühllöcher im Bereich der halben Schaufelblatthöhe größer als der Drosselquerschnitt der Kühllöcher im von der halben Schaufelblatthöhe weiter entfernten Bereich.In order to further adapt the cooling of the leading edge for different airfoil heights as required, each cooling hole preferably has a throttle cross section that adjusts the coolant flow, the throttle cross sections of some cooling holes being of different sizes. The throttle cross sections of the cooling holes in the region of half the blade height are particularly preferably larger than the throttle cross section of the cooling holes in the region further away from half the blade height.

Dieser Ausgestaltung liegt die Erkenntnis zugrunde, dass bei halber Schaufelblatthöhe und der daran unmittelbar angrenzenden Bereiche ein etwas erhöhter Kühlbedarf vorherrscht als in denjenigen Bereichen der Vorderkante, welche von der halben Schaufelblatthöhe weiter entfernt liegen.This configuration is based on the finding that at half the blade height and in the regions immediately adjacent thereto, there is a somewhat greater cooling requirement than in those regions of the leading edge which are further away from half the blade height.

Besonders bevorzugt ist diejenige Ausgestaltung, bei der die zumindest zwei Reihen von Kühllöchern beidseits einer mittleren Staupunktlinie der ankommenden Heißgasströmung angeordnet sind. An dieser Stelle teilt sich die Heißgasströmung auf in einen zur Druckseite und einen zur Saugseite strömenden Anteil aufteilende zu beiden Seiten hin umgelenkt, sodass aufgrund der beidseitigen Anordnung der Kühllöcher die darunter liegende Bauteilwand besonders effizient vor den hohen Temperaturen des Heißgases geschützt ist.The configuration in which the at least two rows of cooling holes are arranged on both sides of a central stagnation point line of the incoming hot gas flow is particularly preferred. At this point, the hot gas flow is divided into a part flowing to the pressure side and a part flowing to the suction side, which is diverted to both sides, so that the component wall underneath is particularly efficiently protected from the high temperatures of the hot gas due to the arrangement of the cooling holes on both sides.

Je nach Ausgestaltung kann es zudem zur Vermeidung einer lokalen thermischen Überbelastung der Vorderkante hilfreich sein, wenn bei der vorgenannten Ausgestaltung druckseitig neben den zumindest zwei Reihen eine weitere, jedoch verkürzte Reihe von im Wesentlichen gleichmäßig beabstandeten Kühllöchern vorgesehen ist, wobei die Länge der weiteren Reihe zwischen 50% und 60% der Schaufelblatthöhe beträgt und die weitere Reihe von Kühllöchern im Wesentlichen mittig zwischen den beiden Enden des Schaufelblatts angeordnet ist. Die weitere Reihe ist im Sinne dieser Anmeldung solange im Wesentlichen mittig angeordnet, solange diese von der halben Schaufelblatthöhe in zwei Teile geteilt ist, deren kürzerer Teil nicht kürzer als 1/3 der Länge der weiteren Reihe ist. Die Länge der weiteren Reihe von Kühllöchern wird in gleicher Richtung wie die Schaufelblatthöhe erfasst.Depending on the design, it can also be helpful to avoid local thermal overloading of the leading edge if, in the aforementioned design, a further but shortened row of essentially evenly spaced cooling holes is provided on the pressure side in addition to the at least two rows, with the length of the further row between 50% and 60% of the airfoil height and the further row of cooling holes is arranged substantially centrally between the two ends of the airfoil. For the purposes of this application, the further row is arranged essentially centrally as long as it is divided by half the airfoil height into two parts, the shorter part of which is not shorter than 1/3 of the length of the further row. The length of the further row of cooling holes is recorded in the same direction as the airfoil height.

Bevorzugtermaßen ist das Schaufelblatt Teil einer Turbinenschaufel, insbesondere einer Turbinenleitschaufel einer stationären Gasturbine.The airfoil is preferably part of a turbine blade, in particular a turbine guide blade of a stationary gas turbine.

Im Folgenden wird nun die Erfindung anhand der in den Figuren dargestellten Ausführungsbeispiele näher beschrieben und erläutert. Darin zeigen:

Figur 1
in perspektivischer Darstellung eine Turbinenlaufschaufel mit einem Schaufelblatt gemäß einem ersten Beispiel,
Figur 2
in perspektivischer Darstellung eine Turbinenlaufschaufel mit einem Schaufelblatt gemäß einem zweiten Beispiel,
Figur 3
das Schaufelprofil des Schaufelblatts gemäß dem ersten Beispiel und
Figur 4
in perspektivischer Darstellung eine Turbinenleitschaufel mit einem erfindungsgemäßen Schaufelblatt gemäß dem Ausführungsbeispiel der Erfindung.
The invention will now be described and explained in more detail below with reference to the exemplary embodiments illustrated in the figures. Show in it:
figure 1
a perspective view of a turbine rotor blade with a blade airfoil according to a first example,
figure 2
a perspective view of a turbine rotor blade with a blade airfoil according to a second example,
figure 3
the airfoil of the airfoil according to the first example and
figure 4
a perspective view of a turbine vane with a blade according to the invention according to the embodiment of the invention.

In den Figuren können gleiche oder gleichwirkende Merkmale jeweils mit den gleichen Bezugszeichen versehen sein. Die dargestellten Merkmale und deren Größenverhältnisse untereinander sind grundsätzlich nicht als maßstabsgerecht anzusehen, vielmehr können einzelne Elemente zur besseren Darstellung und/oder zum besseren Verständnis im Verhältnis größer dimensioniert dargestellt sein.In the figures, features that are the same or have the same effect can each be provided with the same reference symbols. The features shown and their proportions to one another are not to be regarded as true to scale, rather individual elements can be shown with larger proportions for better representation and/or better understanding.

In Figur 1 ist in perspektivischer Darstellung eine Turbinenlaufschaufel 10 dargestellt. Die Turbinenschaufel 10 umfasst aufeinanderfolgend einen im Wesentlichen tannenbaumförmigen Schaufelfuß 12, an den sich als Endwand eine Heißgasplattform 14 anschließt. An dessen dem Heißgas S zugewandten Oberfläche ist ein Schaufelblatt 16 gemäß einem ersten Beispiel angeordnet. Das Schaufelblatt 16 umfasst bekanntermaßen eine Vorderkante 18 und eine Hinterkante 20, zwischen denen sich eine Saugseitenwand 17 und eine Druckseitenwand 19 erstreckt. In einer Querrichtung dazu erstreckt sich das Schaufelblatt 16 von einem fußseitigen Ende 21 bei 0% Schaufelblatthöhe zu einem spitzenseitigen Ende 23 bei 100% Schaufelblatthöhe. Längs der Vorderkante 18 sind zwei Reihen R1, R2 von Kühllöchern 22 angeordnet. Die beiden Reihen R1, R2 verlaufen entlang einer Wellenlinie mit mehreren Wellentälern und Wellenbergen und sind gleichzeitig beidseits einer mittleren Staupunktlinie 24 angeordnet.In figure 1 a turbine rotor blade 10 is shown in a perspective view. The turbine blade 10 successively comprises an essentially fir-tree-shaped blade root 12, which is adjoined by a hot-gas platform 14 as the end wall. On its surface facing the hot gas S, an airfoil 16 according to a first example is arranged. The airfoil 16 is known to include a leading edge 18 and a trailing edge 20 between which a suction sidewall 17 and a pressure sidewall 19 extend. In a direction transverse thereto, the airfoil 16 extends from a root end 21 at 0% airfoil height to a tip end 23 at 100% airfoil height. Two rows R 1 , R 2 of cooling holes 22 are arranged along the leading edge 18 . The two rows R 1 , R 2 run along a wavy line with a plurality of wave troughs and wave crests and are simultaneously arranged on both sides of a central stagnation point line 24 .

Ein zweites Beispiel ist in Figur 2 dargestellt. Anstelle der insgesamt wellenförmigen Anordnung von Kühllöchern 22 in den Reihen R1, R2 ist hier ein Bereich geradlinig, gefolgt von einem bauchigen Abschnitt. Im Detail sind die beiden Reihen R1, R2 von Kühllöchern 22 in dem ersten, radial innenliegenden Bereich so angeordnet, dass sie parallel zur Vorderkante 18 beidseits dieser angeordnet sind. Dieser erste Bereich B1 erstreckt sich zwischen 0% und etwa 40% Schaufelblatthöhe. Daran radial außen anschließend ist ein zweiter Bereich B2 vorgesehen. Dieser endet auf einer Schaufelblatthöhe von etwa 75%. In diesem Bereich verschieben sich die Kühllöcher 22 beider Reihen R1, R2 mit zunehmender Höhe weiter in Richtung Druckseite, bis sie bei etwa 75% Schaufelblatthöhe die Maximalverschiebung von der Vorderkante 18 weg erreicht haben. In dem sich daran anschließenden dritten Bereich B3 verlagern sich die Kühllöcher 22 der beiden Reihen R1, R2 in Richtung der Vorderkante 18 wieder zurück.A second example is in figure 2 shown. Instead of the generally wavy arrangement of cooling holes 22 in the rows R 1 , R 2 , here a region is straight, followed by a bulbous section. In detail, the two rows R 1 , R 2 of cooling holes 22 are arranged in the first, radially inner area in such a way that they are arranged parallel to the leading edge 18 on both sides thereof. This first range B 1 extends between 0% and about 40% airfoil height. A second area B 2 is provided radially on the outside. This ends at an airfoil height of about 75%. In this area, the cooling holes 22 of both rows R 1 , R 2 move further towards the pressure side with increasing height until they have reached the maximum displacement away from the leading edge 18 at about 75% airfoil height. In the adjoining third area B 3 , the cooling holes 22 of the two rows R 1 , R 2 shift back again in the direction of the front edge 18 .

Mit Hilfe der beiden dargestellten Beispiele ist es möglich, die Vorderkante 18 der Turbinenschaufel 10 für unterschiedliche Anströmungsbedingungen und unterschiedliche Betriebsweisen anzupassen unter Erreichung einer weiterhin hinreichenden Kühlung der Vorderkante 18 bei moderatem Einsatz von Kühlmittel. Insbesondere durch die Verwendung von lediglich zwei Reihen R1, R2 an Kühllöchern 22 anstelle von drei Reihen lässt sich der Herstellungsaufwand bei der Turbinenschaufel 10 signifikant reduzieren. Eine geringere Anzahl von Kühllöchern 22 bedeutet zugleich, dass das Risiko der Risserzeugung gesenkt worden ist. Weiterhin wird die Menge an Kühlmittel, beispielsweise Kühlluft, reduziert, was zur Erhöhung des Turbinenwirkungsgrades beiträgt.With the help of the two examples shown, it is possible to adapt the leading edge 18 of the turbine blade 10 for different flow conditions and different modes of operation while still achieving adequate cooling of the leading edge 18 with moderate use of coolant. In particular, through the use of only two rows R 1 , R 2 of cooling holes 22 instead of three rows, the manufacturing effort for the turbine blade 10 can be significantly reduced. At the same time, a smaller number of cooling holes 22 means that the risk of crack generation has been reduced. Furthermore, the amount of coolant, for example cooling air, is reduced, which contributes to increasing the turbine efficiency.

In beiden Figuren sind die Kühllöcher 22 lediglich schematisch als Kreise dargestellt, wobei deren Drosselquerschnitte durch unterschiedlich große Kreise schematisch dargestellt worden sind. Selbstverständlich kann es sich bei den Kühllöchern 22 um Filmkühllöcher handeln, die eine diffusorartige Öffnung aufweisen. Deren Diffusor kann sogar profiliert ausgestaltet sein. Auch ein auf der Oberfläche des Schaufelblatts 16 quer zu erfassender Abstand A zwischen den Kühllöchern 22 kann auf unterschiedlichen Schaufelblatthöhen unterschiedlich groß sein.In both figures, the cooling holes 22 are shown only schematically as circles, with their throttle cross sections being shown schematically by circles of different sizes. Of course, the cooling holes 22 can be film cooling holes that have a diffuser-like opening. Its diffuser can even be designed with a profile. A distance A between the cooling holes 22 to be measured transversely on the surface of the airfoil 16 can also be of different sizes at different airfoil heights.

Figur 3 zeigt zudem als ein Schaufelprofil 28 den Querschnitt durch das Schaufelblatt 16 des ersten Beispiels gemäß Figur 1. Zwischen der Saugseitenwand 17 und der Druckseitenwand 19 erstreckt sich mittig einer gedachten Linie, welche als Schaufelprofilmittenlinie oder auch als Camberline bekannt ist. Die Schaufelprofilmittenlinie ist mit dem Bezugszeichen 30 versehen. Der zuvorderst angeordnete Punkt der Schaufelprofilmittenlinie 30 definiert die Vorderkante 18. Je nach tatsächlicher Anströmung bzw. Fehlanströmung des Schaufelprofils 28 kann der Stagnationspunkt 25 abseits der Vorderkante 18 hin zur Druckseite 19 oder hin zur Saugseite 17 geringfügig verschoben sein. Die (mittleren) Stagnationspunkte 25 jedes Schaufelprofilschnitts, die auf beliebigen Schaufelblatthöhen ermittelbar sind, bilden gemeinsam die Staupunktlinie 24. Der Nasenradius ist mit R bezeichnet. figure 3 FIG. 12 also shows, as a blade profile 28, the cross section through the airfoil 16 of the first example according to FIG figure 1 . Between the suction sidewall 17 and the pressure sidewall 19 extends in the middle of an imaginary line, which is known as the blade profile center line or also as the camberline. The blade profile center line is provided with reference number 30 . The foremost arranged point of the blade profile center line 30 defines the leading edge 18. Depending on the actual inflow or incorrect inflow of the blade profile 28, the stagnation point 25 can be slightly shifted away from the leading edge 18 towards the pressure side 19 or towards the suction side 17. The (middle) stagnation points 25 of each blade profile section, which can be determined at any blade height, together form the stagnation point line 24. The nose radius is denoted by R.

Ein Ausführungsbeispiel der Erfindung ist in Figur 4 dargestellt. Sie zeigt perspektivisch eine als Leitschaufel ausgestaltete Turbinenschaufel, wobei der Schaufelfuß 12 zwei hakenförmige Schienen zur Befestigung der Schaufel an einen nicht weiter dargestellten Schaufelträger umfasst. Im Gegensatz zu der in Figur 1 dargestellten Laufschaufel ist sowohl an dem fußseitigen Ende 21 als auch an dem spitzenseitigen Ende 23 des Schaufelblatts eine Plattform 14 zur Begrenzung des Strömungspfad vorgesehen. Dazwischen erstreckt sich das Schaufelblatt 16 längs seiner Schaufelblatthöhe. Wie detaillierte Untersuchungen gezeigt haben, ist bei derartigen Leitschaufeln die Staupunktlinie 24 zu den Enden 21, 23 des Schaufelblatts 16 hin zusehends in Richtung der Saugseite verschoben. Dementsprechend sind auch die zumindest zwei Reihen R1, R2 von Kühllöchern 18 analog angeordnet: beginnend mit den Kühllöchern auf der halben Schaufelblatthöhe sind innerhalb jeder Reihe R1, R2 die mit geringer werdendem Abstand zu den Plattformen 14 hin angeordneten Kühllöcher weiter saugseitig angeordnet. Die Staupunktlinie 24 ist geringfügig gekrümmt, ohne eine Änderung des Vorzeichens ihrer Krümmung. Zudem ist eine weitere, jedoch verkürzte Reihe von im Wesentlichen gleichmäßige beabstandete Kühllöchern 18 druckseitig neben den beiden Reihen R1, R2 vorgesehen. Diese weitere Reihe R3 ist gemäß diesem Ausführungsbeispiel mittig zwischen den beiden Plattformen 14 bzw. den beiden Enden 21, 23 angeordnet und erstreckt sich lediglich über eine Länge von 55 % der Schaufelblatthöhe. Sie ist somit kürzer als die beiden Reihen R1, R2. Falls erforderlich, können lokal weitere, vereinzelte Kühllöcher nahe der Vorderkante vorgesehen sein. Insgesamt betrifft die Erfindung ein Schaufelblatt 16 für eine Turbinenschaufel 10, umfassend eine von einem Heißgas S anströmbare Vorderkante 18, von der aus sich eine Saugseitenwand 17 und eine Druckseitenwand 19 zu einer Hinterkante 20 des Schaufelblatts 16 erstrecken, wobei das Schaufelblatt 16 in einer Querrichtung dazu sich von einem fußseitigen Ende 21 mit einer Schaufelblatthöhe von 0% zu einem spitzenseitigen Ende 23 mit einer Schaufelblatthöhe von 100% erstreckt, mit zwei längs der Vorderkante angeordneten Reihen R1, R2 von Kühllöchern 22, die zueinander einen senkrecht zur Vorderkante 18 zu erfassenden ersten Abstand A aufweisen. Um eine Turbinenschaufel bereitzustellen, welche mit vermindertem Kühlaufwand eine weiterhin zuverlässige Kühlung der Vorderkante 18 für unterschiedliche Betriebsbedingungen einsetzbar ist, wird vorgeschlagen, dass die beiden Reihen R1, R2 von Kühllöchern 22 zumindest teilweise längs der Vorderkante 18 auf einer Wellenlinie angeordnet sind. Die Wellenlinie 24 ist ohne eine Änderung des Vorzeichens ihrer Krümmung derart geringfügig gekrümmt, dass die Kühllöcher 18 jeder der zumindest zwei Reihen (Ri, R2) sowohl an dem fußseitigen Ende 21 und an dem spitzenseitigen Ende 23 des Schaufelblatts weiter saugseitig angeordnet sind als die Kühllöcher 18 der entsprechenden Reihe (Ri, R2) auf halber Schaufelblatthöhe.An embodiment of the invention is in figure 4 shown. It shows a perspective view of a turbine blade configured as a guide blade, with the blade root 12 comprising two hook-shaped rails for fastening the blade to a blade carrier (not shown in any more detail). In contrast to the in figure 1 In the rotor blade shown, a platform 14 is provided at both the root end 21 and the tip end 23 of the airfoil to limit the flow path. In between, the airfoil 16 extends along its airfoil height. As detailed investigations have shown, with guide vanes of this type, the stagnation point line 24 is increasingly shifted towards the ends 21, 23 of the vane blade 16 in the direction of the suction side. Accordingly, the at least two rows R 1 , R 2 of cooling holes 18 are also arranged analogously: starting with the cooling holes at half the height of the airfoil, within each row R 1 , R 2 the cooling holes arranged with decreasing spacing towards the platforms 14 are arranged further on the suction side . The stagnation point line 24 is slightly curved without changing the sign of its curvature. In addition, a further but shortened row of substantially evenly spaced cooling holes 18 is provided on the pressure side next to the two rows R 1 , R 2 . This further row R 3 is according to this embodiment in the middle between the two platforms 14 and the two ends 21, 23 and extends over a length of only 55% of the blade height. It is therefore shorter than the two rows R 1 , R 2 . If necessary, further isolated cooling holes can be provided locally near the leading edge. Overall, the invention relates to an airfoil 16 for a turbine blade 10, comprising a leading edge 18 against which a hot gas S can flow, from which a suction sidewall 17 and a pressure sidewall 19 extend to a trailing edge 20 of the airfoil 16, the airfoil 16 being in a transverse direction thereto extending from a root end 21 with an airfoil height of 0% to a tip end 23 with an airfoil height of 100%, with two rows R 1 , R 2 of cooling holes 22 arranged along the leading edge, the mutually perpendicular to the leading edge 18 to be detected have first distance A. In order to provide a turbine blade which can be used with reduced cooling effort to continue to reliably cool the leading edge 18 for different operating conditions, it is proposed that the two rows R 1 , R 2 of cooling holes 22 be arranged at least partially along the leading edge 18 on a wavy line. The wavy line 24 is slightly curved without changing the sign of its curvature such that the cooling holes 18 of each of the at least two rows (Ri, R2) are arranged further on the suction side than the cooling holes at both the root end 21 and the tip end 23 of the airfoil 18 of the corresponding row (Ri, R2) at half blade height.

Claims (9)

  1. Hollow aerofoil (16) for a turbine blade,
    comprising a leading edge against which a hot gas (S) is able to flow and from which a suction-side wall (17) and a pressure-side wall (19) extend to a trailing edge (20) of the aerofoil (16), wherein, in a transverse direction with respect thereto, the aerofoil (16) extends from a root-side end at an aerofoil height of 0% to a tip-side end (23) at an aerofoil height of 100%,
    having at least two series (R1, R2) of cooling holes (22) that are arranged along the leading edge (18), which, with respect to one another, have a first spacing (A) which is to be measured perpendicularly to the leading edge (18), wherein the at least two series (R1, R2) of cooling holes (22) are arranged at least partially on a wavy line along the leading edge (18),
    characterized in that
    the wavy line (24), without a change in sign of its curvature, is slightly curved in such a way that, both at the root-side end (21) and at the tip-side end (23) of the aerofoil, the cooling holes (18) of each of the at least two series (R1, R2) are arranged further to the suction side than the cooling holes (18) of the corresponding series (R1, R2) at the aerofoil mid-height.
  2. Aerofoil according to Claim 1,
    in which the first spacing (A) between the at least two series (R1, R2) varies along the leading edge (18).
  3. Aerofoil according to either of the preceding claims, in which a blade profile (28) is able to be determined for any aerofoil height, which blade profile (28) has a nose radius (R) in the region of the leading edge (18), wherein, at the height of cooling holes (22), the blade profiles have between the at least two series (R1, R2) a first spacing (A) whose size lies in the range between 0.4 and 0.7 times the associated nose radius.
  4. Aerofoil according to one of the preceding claims,
    in which the first spacing (A), at the aerofoil mid-height, is at its smallest and increases towards the two ends.
  5. Aerofoil according to one of the preceding claims,
    in which each cooling hole has a throttle cross section which sets the cooling medium throughflow, wherein the throttle cross sections of some cooling holes (22) are of different sizes.
  6. Aerofoil according to one of the preceding claims,
    in which the throttle cross sections of the cooling holes (22) in the region of the aerofoil mid-height are larger than the throttle cross section of the cooling holes (22) in the region further away from the aerofoil mid-height.
  7. Aerofoil according to one of the preceding claims,
    in which the at least two series (R1, R2) of cooling holes (22) are arranged on both sides of a stagnation point line (24) of the incoming hot-gas flow.
  8. Aerofoil according to one of the preceding claims,
    in which, besides the at least two series (R1, R2), a further series (R3) of cooling holes (18) is provided adjacently on the pressure side, wherein a length of the further series (R3) is between 50% and 60% of the aerofoil height, and the further series (R3) is arranged substantially centrally between the two ends (21, 23) of the aerofoil (16).
  9. Turbine blade (10) for a stationary gas turbine, comprising an aerofoil (16) according to one of the preceding claims, preferably in the form of a turbine guide blade.
EP19723730.8A 2018-05-04 2019-05-03 Airfoil for a turbine blade Active EP3762587B1 (en)

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EP18170731.6A EP3564483A1 (en) 2018-05-04 2018-05-04 Blade base for a turbine blade
PCT/EP2019/061354 WO2019211427A1 (en) 2018-05-04 2019-05-03 Aerofoil for a turbine blade

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EP3762587B1 true EP3762587B1 (en) 2022-04-13

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EP3564483A1 (en) * 2018-05-04 2019-11-06 Siemens Aktiengesellschaft Blade base for a turbine blade
JP7224928B2 (en) * 2019-01-17 2023-02-20 三菱重工業株式会社 Turbine rotor blades and gas turbines
KR102507408B1 (en) 2022-11-11 2023-03-08 터보파워텍(주) Rrepairing Airfoil Process of gas turbine blades by 3D printing

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6869268B2 (en) * 2002-09-05 2005-03-22 Siemens Westinghouse Power Corporation Combustion turbine with airfoil having enhanced leading edge diffusion holes and related methods
US7217094B2 (en) 2004-10-18 2007-05-15 United Technologies Corporation Airfoil with large fillet and micro-circuit cooling
EP1898051B8 (en) * 2006-08-25 2017-08-02 Ansaldo Energia IP UK Limited Gas turbine airfoil with leading edge cooling
US8105030B2 (en) 2008-08-14 2012-01-31 United Technologies Corporation Cooled airfoils and gas turbine engine systems involving such airfoils
CA2880540A1 (en) * 2012-08-06 2014-02-13 General Electric Company Rotating turbine component with preferential hole alignment
US11143038B2 (en) * 2013-03-04 2021-10-12 Raytheon Technologies Corporation Gas turbine engine high lift airfoil cooling in stagnation zone
US10329923B2 (en) * 2014-03-10 2019-06-25 United Technologies Corporation Gas turbine engine airfoil leading edge cooling
US9976423B2 (en) * 2014-12-23 2018-05-22 United Technologies Corporation Airfoil showerhead pattern apparatus and system
US10240462B2 (en) * 2016-01-29 2019-03-26 General Electric Company End wall contour for an axial flow turbine stage
US11286787B2 (en) 2016-09-15 2022-03-29 Raytheon Technologies Corporation Gas turbine engine airfoil with showerhead cooling holes near leading edge
EP3564483A1 (en) * 2018-05-04 2019-11-06 Siemens Aktiengesellschaft Blade base for a turbine blade

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EP3564483A1 (en) 2019-11-06
CN112074652B (en) 2023-05-02
KR102505046B1 (en) 2023-03-06
JP7124122B2 (en) 2022-08-23
US20210156263A1 (en) 2021-05-27
WO2019211427A1 (en) 2019-11-07
CN112074652A (en) 2020-12-11
KR20210002709A (en) 2021-01-08
JP2021522444A (en) 2021-08-30
EP3762587A1 (en) 2021-01-13

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