EP1591724B1 - Gap sealing element for a heat shield - Google Patents

Gap sealing element for a heat shield Download PDF

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Publication number
EP1591724B1
EP1591724B1 EP04010306A EP04010306A EP1591724B1 EP 1591724 B1 EP1591724 B1 EP 1591724B1 EP 04010306 A EP04010306 A EP 04010306A EP 04010306 A EP04010306 A EP 04010306A EP 1591724 B1 EP1591724 B1 EP 1591724B1
Authority
EP
European Patent Office
Prior art keywords
heat shield
gap
sealing element
gap sealing
elements
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Not-in-force
Application number
EP04010306A
Other languages
German (de)
French (fr)
Other versions
EP1591724A1 (en
Inventor
Andreas Heilos
Stefan Dr. Hoffmann
Gerald Lauer
Roland Dr. Liebe
Bernd Dr. Prade
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Priority to AT04010306T priority Critical patent/ATE514905T1/en
Priority to EP04010306A priority patent/EP1591724B1/en
Publication of EP1591724A1 publication Critical patent/EP1591724A1/en
Application granted granted Critical
Publication of EP1591724B1 publication Critical patent/EP1591724B1/en
Anticipated expiration legal-status Critical
Not-in-force legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R3/00—Continuous combustion chambers using liquid or gaseous fuel
    • F23R3/007—Continuous combustion chambers using liquid or gaseous fuel constructed mainly of ceramic components
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M5/00—Casings; Linings; Walls
    • F23M5/04—Supports for linings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23M—CASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M2900/00—Special features of, or arrangements for combustion chambers
    • F23M2900/05005—Sealing means between wall tiles or panels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23R—GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R2900/00—Special features of, or arrangements for continuous combustion chambers; Combustion processes therefor
    • F23R2900/00012—Details of sealing devices

Definitions

  • the present invention relates to a gap sealing element for sealing the gaps between peripheral surfaces of adjacent heat shield elements and a heat shield equipped with such gap sealing elements.
  • the walls of high temperature reactors e.g. the walls of pressurized gas turbine combustors must be protected against hot gas attack by suitable thermal shielding of their supporting structure.
  • the thermal shield may e.g. be achieved by the wall to be protected from the hot gas is lined by a plurality of limited in size individual heat shield elements.
  • Ceramic materials are ideally suited for the construction of a heat shield in comparison to metallic materials because of their high temperature resistance, corrosion resistance and low thermal conductivity. Because of material-typical thermal expansion properties and the temperature differences typically occurring during operation, such as between the ambient temperature at standstill of the gas turbine combustor and the maximum temperature at full load, the thermal mobility of ceramic heat shields must be guaranteed as a result of temperature-dependent expansion, so that no heat shield destructive thermal stresses by hindering the temperature-dependent Elongation occur. Expansion gaps are therefore present between the individual ceramic heat shield elements in order to allow the thermal expansion of the heat shield elements. For safety reasons, the expansion gaps are designed so that they are never completely closed even at maximum temperature of the hot gas.
  • the ceramic heat shield elements have a hot side facing the hot gas and a cold side facing the support structure. They are typically fastened to a support structure by means of retaining elements. In this case engage engaging portions of the holding elements in grooves which are formed in located between the hot side and the cold side peripheral surfaces of the heat shield elements.
  • the holding elements also white holding sections, by means of which they are connected to the support structure, for example. Screwed, so that the heat shield elements are fixed by means of the holding elements on the support structure.
  • the retaining elements are exposed to the hot gas in the operating state of the gas turbine combustion chamber, which penetrates into the expansion gaps between the heat shield elements. Since the retaining elements are usually made of metallic materials for reliability reasons, they are limited in terms of their operating temperature to a lower temperature level compared to ceramic materials. In the gas turbine combustors should therefore be avoided that hot gas penetrates into the expansion column, because otherwise the holding elements or the support structure, which also usually consists of metal, would be excessively heated.
  • One frequently used means to avoid the penetration of hot gas into the expansion column - in this context one speaks of the blocking of the expansion gaps - is the rinsing of the expansion gaps with sufficient air, the so-called. Cooling or sealing air.
  • the support structure typically has cooling air openings, through which cooling air can flow into the expansion gaps.
  • the metallic holding elements have been cooled by means of injected below the holding elements cooling air.
  • the blocking of the gap between the ceramic takes place Heat shield elements not even. This means that more cooling air is required for a safe blocking of the gap against the penetration of the hot gas, as would theoretically be necessary to block the gap.
  • effective cooling of the holding sections of the holding elements which are most likely to be exposed to the hot gas is made more difficult.
  • a combustor liner having heat shield bricks in which flow barriers are disposed in the expansion nips between the heat shield bricks to reduce the penetration of hot gas into the expansion nips.
  • the heat shield bricks of this combustion chamber lining have grooves on their peripheral surfaces into which a flow barrier arranged in the gap between two heat shield bricks engages.
  • the flow barriers are fixed by means of retaining anchors in the expansion gap.
  • the EP 1 260 767 A1 discloses a gap sealing element for sealing gaps between adjacent heat shield elements.
  • the gap sealing element is compressed prior to insertion into the gap, so that a resilient contact with the heat shield elements enables a good seal.
  • the EP 1 022 437 A1 discloses a sealing element for sealing gaps, wherein the sealing element is formed as a metal seal spring or metallic spring seal.
  • the first object is achieved by a gap sealing element according to claim 1 and the second object by a heat shield according to claim 8.
  • a gap-sealing element according to the invention for sealing gaps between adjacent heat shield elements comprises at least one resilient section which is designed to exert a spring force such that the gap sealing element inserted into a gap between adjacent heat shield elements is held in the gap by means of a press fit, wherein the at least one resilient section forms a curvature which protrudes perpendicular to the direction of action of the spring force for producing the clamping seat, wherein the material thickness in the region of the curvature is greater than in the remaining areas of the gap sealing element.
  • the gap sealing element according to the invention can in particular be configured such for sealing gaps between opposing and each having a groove peripheral surfaces of adjacent heat shield elements that it is sealingly insert the gap in the grooves of the peripheral surfaces of adjacent heat shield elements such that a part of him in the groove of a peripheral surface and another part is disposed in the groove of the opposite peripheral surface.
  • the at least one resilient portion has a curvature, which protrudes in the direction of the spring force for producing the clamping seat.
  • the curvature can then form a support portion which acts on a groove wall, for example on the groove wall, which belongs to the support structure of the facing portion of the heat shield element, and the gap sealing element against the opposite groove wall, ie against the wall of the gas turbine combustor facing portion of the heat shield element suppressed.
  • the curvature can also take place on the groove wall which faces the support structure of the portion of the heat shield element also belongs to the supporting structure.
  • the gap sealing element is preferably designed such that it does not extend to the groove bottoms of the grooves.
  • the resilient portion has a curvature which protrudes perpendicular to the direction of the spring force for producing the clamping seat.
  • the gap-sealing element may in particular comprise two support sections for supporting on the groove bottoms of the grooves, which are connected to one another by the curved elastic section.
  • the curvature can in particular have a profile which approximately corresponds to a circular section with an opening angle ⁇ and a curvature radius R.
  • the opening angle preferably comprises a value in the range of 50 ° to 60 °, the radius R a value in the range of 30 to 40 mm and the curvature radius L a value in the range of 8 to 10 mm.
  • the material thickness in the region of the curvature is greater than in the other areas of the gap sealing element.
  • the spring force is to be chosen so that they However, the clamping force necessary for a secure clamping can apply, but neither in the spring element nor in the ceramic impermissible stresses arise when the adjacent ceramic heat shield elements expand due to high temperatures and the support sections of the gap sealing element to move towards each other.
  • inventive gap sealing elements have an alternative form of attachment. While the flow barriers in the prior art must be secured by means of retaining anchors, the gap sealing elements according to the invention need only be inserted into the gaps and / or the grooves between the heat shield elements. In the columns and / or in the grooves, they are then held by means of a press fit. Retaining anchors and corresponding counterparts for fixing the retaining anchor are therefore not necessary in the gap sealing element according to the invention.
  • the gap sealing elements according to the invention are used to avoid the contact between the hot gas and the holding elements above the holding elements in the gaps or grooves.
  • the spring force of the resilient portions is chosen such that it provides the necessary clamping force for a secure clamping fit available.
  • the dimensions of the gap sealing element are chosen such that the thermal expansion of the heat shield elements is not hindered, so that neither in the gap sealing element nor in the ceramic undue stresses caused by the reduction of the expansion gap dimensions.
  • inventive gap sealing elements have an alternative form of attachment. While the flow barriers in the prior art must be fastened by means of retaining anchors, the gap sealing elements according to the invention need only in the gaps and / or the grooves to be inserted between the heat shield elements. In the columns and / or in the grooves, they are then held by means of a press fit. Retaining anchors and corresponding counterparts for fixing the retaining anchor are therefore not necessary in the gap sealing element according to the invention.
  • the gap sealing elements according to the invention are used to avoid the contact between the hot gas and the holding elements above the holding elements in the gaps or grooves.
  • the spring force of the resilient portions is chosen such that it provides the necessary clamping force for a secure clamping fit available.
  • the dimensions of the gap sealing element are chosen such that the thermal expansion of the heat shield elements is not hindered, so that neither in the gap sealing element nor in the ceramic undue stresses caused by the reduction of the expansion gap dimensions.
  • a heat shield according to the invention on a support structure for protecting the support structure and / or a wall enclosing the support structure or connected to the support structure against a hot gas comprises a number of heat shield elements adjoining each other by gap-sealing, which can be configured in particular as ceramic heat shield elements.
  • gap sealing elements according to the invention are arranged in the gaps between opposing heat shield elements.
  • the cooling / sealing air consumption of a gas turbine combustion chamber can be reduced. This lowers the combustion temperature and reduces the thermal stress in the ceramic heat shields. As a result, the Reduced NO x emissions and the stress on the ceramic heat shields.
  • the heat shield elements may have the expansion gaps bounding and grooved peripheral surfaces, wherein a gap sealing element is a gap sealingly insert each such into the grooves of the gap bounding peripheral surfaces, that a part of him in the groove of a peripheral surface and another part is arranged in the groove of the opposite peripheral surface.
  • the spring force producing the clamping seat between the support structure and the hot side groove wall of the grooves acts in an alternative embodiment, the spring force between the cold side groove walls and the hot side groove walls, in particular the cold side groove walls and the hot side groove walls of the same groove.
  • the spring force producing the clamping seat acts between the groove bottoms of two opposing grooves. The last two alternatives allow a favorable cooling air flow in the expansion gap, since no portion of the gap sealing element needs to intervene in the region of the expansion gap located between the support structure and the grooves.
  • the support structure has cooling air openings for supplying a cooling fluid in the direction of the gap sealing elements.
  • the gap sealing elements can be blown with impact rays to cool them. In this way, a scaling or melting of the metallic gap sealing elements can be avoided.
  • the outflowing impingement air additionally serves for convective cooling.
  • Fig. 1 shows a first embodiment of the inventive gap sealing element.
  • Fig. 2 shows the gap sealing element FIG. 1 in the built-in heat shield state.
  • Fig. 3 shows a second embodiment of the inventive gap sealing element.
  • Fig. 4 shows the gap sealing element FIG. 3 in the built-in heat shield state.
  • Fig. 5 shows a third embodiment of the inventive gap sealing element.
  • Fig. 6 shows the gap sealing element FIG. 5 in the built-in heat shield state.
  • Fig. 7 shows a fourth embodiment of the inventive gap sealing element.
  • Fig. 8 shows the gap sealing element FIG. 7 in the built-in heat shield state.
  • Fig. 9 shows a fifth embodiment of the inventive gap sealing element
  • Fig. 10 shows the gap sealing element FIG. 9 in the built-in heat shield state.
  • Fig. 11 shows the cooling air flow along a ceramic heat shield element using a gap sealing element according to the invention.
  • FIG. 1 shows a first embodiment of the inventive gap sealing element in a perspective view.
  • the gap sealing element 10 comprises a metallic sealing plate 12 and a curved metal strip 14, whose two ends 15 are fastened to the sealing plate 12, for example by being welded to the sealing plate 12.
  • the curved metal strip 14 forms a resilient projection, which provides for the installation of the gap sealing element 10 in a heat shield for a clamping fit of the gap sealing element 10.
  • FIG. 1a An alternative embodiment of the in Fig. 1 shown sealing element shows Fig. 1a ,
  • illustrated sealing element 10a is the curved metal strip 14a instead of connected at its ends 15a in the middle 17a with the sealing plate 12a. Its free ends 15a form spring elements which, after installation of the gap sealing element 10a, provide a heat shield for a clamping seat of the gap sealing element 10a.
  • sealing element 10b is the curved metal strip 14b as the metal strip 14 in Fig. 1 shaped. In contrast to the metal strip 14, however, it is not welded at both ends 15b, 15c to the sealing plate 12b, but only at one End 15b. The other end 15c is loose and can slide along the sealing plate 12b.
  • the curved metal strip 14b forms as in Fig. 1 a resilient projection, which provides after the installation of the gap sealing element 10b in a heat shield for a clamping fit of the gap sealing element 10b.
  • two separate metal strips may be present, which correspond to one half of the metal strip 14 and the metal strip 14a and are welded to the edge or in the middle of the sealing plate 12 and 12a.
  • FIG. 2 shows the gap sealing element 10 of the first embodiment in the installed state in a heat shield.
  • the figure shows a ceramic heat shield element 16, which is fastened by means of metallic element holder 18 to the support structure 20 of a gas turbine combustor.
  • the heat shield element 16 has a cold side 22, which faces the support structure 20, and a hot side 24, which faces the hot gas in the gas turbine combustion chamber. Between the hot side 24 and the cold side 22 extend first peripheral surfaces 26 and second peripheral surfaces 28, wherein the first peripheral surfaces of the second peripheral surfaces differ in that they have a groove 30 in which an engagement portion (not visible in the figure) of Element holder 18 for holding the ceramic heat shield element 16 engages.
  • the second circumferential surfaces 28 are generally groove-free.
  • the metallic support elements 18 each have, in addition to the engagement portion for engagement with the groove 30 of the heat shield member 16, a mounting portion (not shown) for insertion into a groove 32 of the support structure 20.
  • the mounting portions are then fixed, for example by means of screws, in particular at the bottom of the groove 32nd
  • the ceramic heat shield elements 16 are arranged in such a comprehensive manner that they adjoin each other with their peripheral surfaces 26, wherein between the adjacent peripheral surfaces Dehnspalte remain so that the heat shield elements 16 can extend the transition from cold to hot (operating) state.
  • the dimension of the expansion column is dimensioned so that adjacent heat shield elements 16 do not abut each other even in the hottest state, so as to avoid stresses that could lead to cracking.
  • the expansion gaps bounded by the first peripheral surfaces 26 generally extend in the case of radially symmetrical combustion chambers, but not necessarily in the circumferential direction of the combustion chamber and the expansion gaps bounded by the second peripheral surfaces in the axial direction of the combustion chamber. In FIG. 2 For the sake of clarity, only one heat shield element 16 of the heat shield is shown.
  • the gap sealing elements 10 are arranged to prevent hot gas from flowing from the hot side 24 through the expansion gaps in the direction of the support structure 20.
  • a portion of the sealing plate 12 of the gap sealing elements 10 engages, as in FIG. 2 shown, while in the groove 30 a first expansion gap bounding peripheral surface 26 of a ceramic heat shield element 16, whereas a further portion of the sealing plate 12 in the groove of the opposite first peripheral surface of another ceramic heat shield element (not shown) engages.
  • the gap sealing element 12 is fixed in its position by means of a press fit.
  • the curved metal strip 14 is supported on the support structure 20 to the sealing plate by means of its spring force against the groove walls 33rd the hot side portions of the ceramic heat shield elements 16 to press, so that a clamping fit between the support structure 20 on the one hand and the groove walls 33 on the other hand arises.
  • the dimensions of the sealing plate 12 are chosen so that the side surfaces 13 of the sealing plate 12, the groove bottom 31 of the grooves 30 do not touch, even if the heat shield elements 16 have their greatest thermal expansion. This can prevent the gap seal member or the ceramic heat shield members 16 from being damaged.
  • the gap seal member 10 Since the gap seal member 10 is made of metal, it can not easily be exposed to the temperatures of the hot gas flowing from the combustion chamber through the expansion gaps to the seal plate 12.
  • cooling bores 34 are therefore present in the support structure 20, through which the sealing plate 12 is blown with cooling air.
  • the blown cooling air flows along the sealing plate 12 in the direction of the existing between the second peripheral surfaces 28 Dehnspalte and enters through this into the combustion chamber of the gas turbine, wherein it blocks the expansion gaps located between the second peripheral surfaces 28 against the entry of hot gas.
  • the cooling air flow will be discussed later with reference to FIG Fig. 11 be explained in more detail.
  • FIG. 3 A second embodiment of the inventive gap sealing element is in FIG. 3 shown.
  • the gap sealing element 110 comprises as in FIG. 1 In contrast to the first embodiment, however, two arched metal strips 114, which are resilient and provide a spring force for a clamping fit of the gap sealing element 110, are welded to the sealing plate 112 at a distance next to one another.
  • FIG. 4 shows the gap sealing element 110 of the second embodiment after installation in a ceramic heat shield, with the exception of the gap sealing element 110 substantially with reference to with reference to Fig. 2 corresponds to described heat shield.
  • the ceramic heat shield members 16, the support structure 20, and the support members 18 are not different from the heat shield members 16, the support structure 20, and the support members 18 of the heat shield described with respect to the first embodiment. Structures that are different from those in FIG. 2 Different structures are therefore distinguished by the same reference numerals as in FIG. 2 designated.
  • the gap seal member 110 is inserted into the grooves 30 of opposite circumferential surfaces 26 so as to be pressed against the groove walls 33 of the hot side portions of the ceramic heat shield members 16 and does not contact the groove bottoms 31.
  • the domed metal strips 114 do not abut the support structure 20 to make the press fit. Instead, they are supported on the groove walls 35 of the cold side portions of the heat shield members 16 to press the sealing plate 112 against the groove walls 33 of the hot side portions of the ceramic heat shield members 16 by their spring force. Due to the spring force, the gap sealing element 110 is securely fixed in the grooves 30 of the ceramic heat shield elements 16 by means of a clamping fit, which acts between the groove walls 35 and the groove walls 33.
  • the gap sealing element 110 is blown with cooling air, which exits through cooling air holes 134 in the support structure. Since the curved metal strips 114 in the second embodiment, the cooling air flow through the Dehnspalte less hinder than the up to the support structure 20 extending metal strip 14 of the first embodiment, the Cooling air consumption in comparison to the first embodiment can be further reduced.
  • FIG. 5 shows the gap sealing element 210 of the third embodiment in a perspective view
  • FIG. 6 the gap sealing element FIG. 5 after installation in a ceramic heat shield represents.
  • the ceramic heat shield in this case corresponds, with the exception of the gap sealing element 210, essentially to the heat shield described with reference to the first exemplary embodiment. Structures of the heat shield related to those Fig. 2 are therefore denoted by the same reference numerals as in FIG Fig. 2 designated.
  • the gap-sealing element 210 of the third exemplary embodiment substantially corresponds to a sealing plate 214 which has a profile with a profile course bent in a first expansion direction A and a straight profile profile in a second expansion direction B perpendicular to the first expansion direction. It has in the direction of extension A ends 212, which are both bent in the same direction and whose bending have an approximately semicircular course.
  • the bent ends 212 form support sections, which in the installed state (see FIG. 6 ) over a large area on the groove bottoms 31 of the grooves 30 abut each other opposite peripheral surfaces 26.
  • the support sections 212 are connected to one another in the expansion direction A via a curved spring section 214.
  • the domed spring portion 214 has a cross-section that substantially corresponds to a circular cutout with the radius R and the opening angle ⁇ , wherein the curvature opposite to the curvature of the bend of the support portions 212 has a different sign.
  • the gap sealing element 210 which is made of a metal sheet with a constant thickness of about 1 mm, has due to its curved spring portion 214 spring elastic properties.
  • the spring force of the spring portion 214 causes the support portions 212 to be pressed against the groove bottoms 31 of the grooves 30, so that the gap seal member 210 is press-fitted into the grooves.
  • the gap sealing element 210 can be compressed due to the spring-elastic properties of the spring section 214.
  • the spring force of the spring section 214 causes the gap sealing element to expand, so that the support sections 212 always remain pressed against the groove bottoms 31 during cooling and the clamping fit always safely preserved.
  • the spring elasticity of the gap sealing element 210 depends on the radius R of the arched spring section 214, on the opening angle ⁇ of the arched spring section 214, on the material thickness of the gap sealing element 210 and on a lever L.
  • the lever L results here as the distance of the center of the curved spring portion 214 from an imaginary connecting line between the support portions 212, which connects those points of the support portions 212 to each other, at which attack the heat shield member compressing the force vectors when heating the heat shield elements 16.
  • the radius R of the curved spring portion 214 is large compared to the distance between the support portions 212. Accordingly, the opening angle ⁇ is relatively small.
  • the lever L is about 1 mm.
  • FIGS. 7 and 8th show the gap sealing element 310 of the fourth embodiment in a perspective view, while FIG. 8 the gap sealing element 310 FIG. 7 after installation in a ceramic heat shield represents.
  • the ceramic heat shield in this case corresponds, with the exception of the gap-sealing element 310, essentially to the heat shield described with reference to the first exemplary embodiment. Structures of the heat shield related to those Fig. 2 are therefore denoted by the same reference numerals as in FIG Fig. 2 designated.
  • gap sealing element 310 is similar in its basic structure in FIG. 5 Like this, it has two curved support portions 312 which are connected to each other via a curved spring portion 314. Compared to the curved spring portion 214 of the gap sealing element 210 of the third embodiment, the curved spring portion 314 of the gap sealing element 310 has a cross section with a smaller radius of curvature R, a larger opening angle ⁇ and a larger lever L.
  • the cross section of the support portions 312 is no longer semicircular as in the gap sealing element 210 of the Figures 5 and 6 , Instead, in the support portions 312 of the gap seal member 310, as viewed from the edges 315, to a portion having a circular profile corresponding approximately to a circular cut with an angle between 45 ° and 60 °, a portion where the radius of curvature decreases closes, so that the support portions 312 provide a compressed impression compared to the support portions 212.
  • the gap-sealing element 310 is inserted into the slots 30 of the ceramic heat-shield elements 16 in opposite orientation (see FIG. FIGS. 6 and 8th ). While the gap sealing element 210 in the inserted state, the curvature of the curved spring portion 214 protrudes in the direction of the support members 18 and the support portions 212 are bent toward the support members 18, the curved spring portion 314 bulges in the fourth embodiment of the support members 18, and the Supporting portions 312 of the gap sealing element 310 are bent away from the holding elements 18 in the inserted state. Moreover, the support sections 312 do not lie against the groove bottoms 31 over such a large area as the support sections 212 of the third exemplary embodiment. In the support sections 312 of the fourth exemplary embodiment, the installation is essentially limited to the sections of the groove bottoms 31 facing the hot-side section of the heat shield element.
  • the gap sealing element 310 has a lower rigidity.
  • the groove bottoms 31 move toward each other due to the thermal expansion of the heat shield members 16, less stress is generated in the gap seal member 310 than in the gap seal member 210.
  • FIG. 9 shows the gap sealing element 410 of the fifth embodiment in a perspective view
  • FIG. 10 the gap sealing element 410 FIG. 9 after installation in a ceramic heat shield represents.
  • the ceramic heat shield corresponds to the gap sealing element 410 substantially with respect to the first embodiment described heat shield. Structures of the heat shield related to those Fig. 2 are therefore denoted by the same reference numerals as in FIG Fig. 2 designated.
  • the gap-sealing element 410 like the gap-sealing elements 210 and 310 of the third and fourth embodiment, has a curved spring section 414 and two support sections 412.
  • the curved spring portion 414 has a radius of curvature which is approximately equal to that of the fourth embodiment.
  • the opening angle ⁇ and the lever L are significantly larger than in the fourth embodiment.
  • the support portions 412 are formed in the fifth embodiment only as kinking edges of the gap sealing element 410. They have only a slight curvature, which is adapted to the contour of the groove bottom 31 (see FIG. 10 ).
  • the material thickness of the gap sealing element 410 is not constant along the expansion direction A, but has the greatest material thickness in the center of the arched spring section 414 with approximately 1.2 mm. In the direction of the support portions 412, the material thickness decreases linearly and reaches in the vicinity of the support portions 412 about a value of 0.6 mm. Along the expansion direction B, the material thickness is constant as in the exemplary embodiments three and four.
  • the gap seal member 410 is inserted into the grooves 30 of the ceramic heat shield members 16 of a hit sign in the same orientation as the gap seal member 310 of the fourth embodiment.
  • the support sections 412 lie substantially in the direction of the groove wall 35 of the cold-side section of the heat shield elements 16 displaced toward the groove bottom 31.
  • the curved spring portion 414 spans the Engagement portions of the holding elements 18 practically completely.
  • the geometry of the fifth embodiment has a particularly good sealing function and particularly favorable stiffness and stress properties.
  • the radius of curvature R of the arched spring portion 414 is in the range between 30 and 40 mm, preferably at about 35 mm, the opening angle in the range between 50 ° and 60 °, preferably at about 56 °, and the lever in the range between 8 and 10 mm, preferably at about 9 mm.
  • the material thickness of the gap sealing element 410 decreases from about 1.2 mm in the center of the arched spring section to about 0.6 mm at the edge of the arched spring section 414. In the area of the support sections 412, the material thickness then increases again somewhat.
  • FIG. 11 The flow conditions along a ceramic heat shield element 16 with built-in gap sealing element are in FIG. 11 shown.
  • a gap sealing element of the fifth embodiment is installed.
  • it could also be installed gap sealing elements of the other embodiments.
  • the cooling air flows - in FIG. 11 if these are four cooling air flows corresponding to the number of cooling air openings 34, they exit from the cooling air openings 34 in the direction of the gap sealing element 410.
  • the cooling air streams are deflected substantially at right angles in such a way that they flow below the gap sealing element 410 parallel to the gap sealing element 410.
  • the cooling air flows reach an expansion gap between two opposite second peripheral surfaces 28, they enter this expansion gap and change their flow direction again by approx. 90 °, so that they now flow away from the support structure 20, ie in the direction of the gas turbine combustor.
  • the expansion gaps between two opposite second peripheral surfaces 28 are shut off by the cooling air against the penetration of hot gas from the gas turbine combustor.
  • the second peripheral surfaces 28 may also have a convex structure instead of a planar structure, which results in different velocity distributions of the cooling air flow.
  • the flow conditions along the ceramic heat shield elements also depend on the shape of the gap sealing elements and on the arrangement of the outlet openings 34 for the cooling air flows.
  • the entirety of the gap sealing element, the arrangement of the cooling air outlet openings 34 and the shaping of the heat shield element 16, in particular its second peripheral surfaces 28, must always be taken into account.
  • good results can be achieved in the optimization, if gap sealing elements 410 according to the fifth embodiment are used and the support structure 20 contains in the area between the element holders 18 six cooling air openings 34 which extend linearly between the element holders 18, an outlet opening of about 2, 25 mm and about 3.8 mm spaced apart from each other.
  • the ceramic heat shield elements have a square structure with an edge length of 200 mm and a thickness of 38 mm.

Abstract

The seal (10) includes a resilient section (14) for ensuring that it remains press-fitted inside the gap. The resilient section is curved. An independent claim is also included for a heat shield mounted on a support structure (20) and comprising a number of sections (16) separated by gaps containing these seals.

Description

Die vorliegende Erfindung betrifft ein Spaltdichtelement zum Abdichten von den Spalten zwischen Umfangsflächen einander benachbarter Hitzeschildelemente sowie ein mit derartigen Spaltdichtelementen ausgestatteter Hitzeschild.The present invention relates to a gap sealing element for sealing the gaps between peripheral surfaces of adjacent heat shield elements and a heat shield equipped with such gap sealing elements.

Die Wände von Hochtemperatur-Reaktoren, wie z.B. die Wände von unter Druck betriebenen Gasturbinenbrennkammern, müssen mit einer geeigneten thermischen Abschirmung ihrer tragenden Struktur gegen Heißgasangriff geschützt werden. Die thermische Abschirmung kann z.B. dadurch erreicht werden, dass die vor dem Heißgas zu schützende Wand durch eine Vielzahl von in ihrer Größe begrenzten einzelnen Hitzeschildelementen ausgekleidet wird.The walls of high temperature reactors, e.g. the walls of pressurized gas turbine combustors must be protected against hot gas attack by suitable thermal shielding of their supporting structure. The thermal shield may e.g. be achieved by the wall to be protected from the hot gas is lined by a plurality of limited in size individual heat shield elements.

Keramische Materialien bieten sich für den Aufbau eines Hitzeschildes im Vergleich zu metallischen Werkstoffen aufgrund ihrer hohen Temperaturbeständigkeit, Korrosionsbeständigkeit und niedrigen Wärmeleitfähigkeit idealerweise an. Wegen materialtypischer Wärmedehnungseigenschaften und der im Rahmen des Betriebs typischerweise auftretenden Temperaturunterschiede, etwa zwischen der Umgebungstemperatur bei Stillstand der Gasturbinenbrennkammer und der maximalen Temperatur bei Volllast, muss die Wärmebeweglichkeit keramischer Hitzeschilde in Folge temperaturabhängiger Dehnung gewährleistet sein, damit keine den Hitzeschild zerstörenden Wärmespannungen durch Behinderung der temperaturabhängigen Dehnung auftreten. Zwischen den einzelnen keramischen Hitzeschildelementen sind daher Dehnspalte vorhanden, um die Wärmeausdehnung der Hitzeschildelemente zu ermöglichen. Aus Sicherheitsgründen sind die Dehnspalte so ausgelegt, dass die auch bei maximaler Temperatur des Heißgases nie völlig geschlossen sind.Ceramic materials are ideally suited for the construction of a heat shield in comparison to metallic materials because of their high temperature resistance, corrosion resistance and low thermal conductivity. Because of material-typical thermal expansion properties and the temperature differences typically occurring during operation, such as between the ambient temperature at standstill of the gas turbine combustor and the maximum temperature at full load, the thermal mobility of ceramic heat shields must be guaranteed as a result of temperature-dependent expansion, so that no heat shield destructive thermal stresses by hindering the temperature-dependent Elongation occur. Expansion gaps are therefore present between the individual ceramic heat shield elements in order to allow the thermal expansion of the heat shield elements. For safety reasons, the expansion gaps are designed so that they are never completely closed even at maximum temperature of the hot gas.

Die keramischen Hitzeschildelemente weisen eine dem Heißgas zuzuwendende Heißseite und eine der Tragstruktur zuzuwendende Kaltseite auf. Sie werden typischerweise mittels Halteelemente an einer Tragstruktur befestigt. Dabei greifen Eingriffsabschnitte der Halteelemente in Nuten ein, die in zwischen der Heißseite und der Kaltseite befindlichen Umfangsflächen der Hitzeschildelemente ausgebildet sind. Die Haltelemente weißen außerdem Halteabschnitte auf, mittels derer sie mit der Tragstruktur verbunden, bspw. verschraubt, werden, sodass die Hitzeschildelemente mittels der Halteelemente an der Tragstruktur fixiert sind.The ceramic heat shield elements have a hot side facing the hot gas and a cold side facing the support structure. They are typically fastened to a support structure by means of retaining elements. In this case engage engaging portions of the holding elements in grooves which are formed in located between the hot side and the cold side peripheral surfaces of the heat shield elements. The holding elements also white holding sections, by means of which they are connected to the support structure, for example. Screwed, so that the heat shield elements are fixed by means of the holding elements on the support structure.

Ohne weitere Maßnahmen sind die Halteelemente im Betriebszustand der Gasturbinen-Brennkammer dem Heißgas ausgesetzt, welches in die Dehnspalte zwischen den Hitzeschildelementen eindringt. Da die Halteelemente aus Zuverlässigkeitsgründen üblicherweise aus metallischen Werkstoffen hergestellt sind, sind sie bezüglich ihrer Einsatztemperatur auf ein im Vergleich zu keramischen Werkstoffen niedrigeres Temperaturniveau begrenzt. In den Gasturbinenbrennkammern soll daher vermieden werden, dass Heißgas in die Dehnspalte eindringt, weil sonst die Halteelemente bzw. die Tragstruktur, die in der Regel ebenfalls aus Metall besteht, übermäßig erwärmt würden. Ein häufig zur Anwendung kommendes Mittel, das Eindringen von Heißgas in die Dehnspalte zu vermeiden - man spricht in diesem Zusammenhang vom Sperren der Dehnspalte - ist das Spülen der Dehnspalte mit ausreichend Luft, der sog. Kühl- oder Sperrluft. Dazu weist die Tragstruktur typischerweise Kühlluftöffnungen auf, durch die Kühlluft in die Dehnspalte strömen kann.Without further measures, the retaining elements are exposed to the hot gas in the operating state of the gas turbine combustion chamber, which penetrates into the expansion gaps between the heat shield elements. Since the retaining elements are usually made of metallic materials for reliability reasons, they are limited in terms of their operating temperature to a lower temperature level compared to ceramic materials. In the gas turbine combustors should therefore be avoided that hot gas penetrates into the expansion column, because otherwise the holding elements or the support structure, which also usually consists of metal, would be excessively heated. One frequently used means to avoid the penetration of hot gas into the expansion column - in this context one speaks of the blocking of the expansion gaps - is the rinsing of the expansion gaps with sufficient air, the so-called. Cooling or sealing air. For this purpose, the support structure typically has cooling air openings, through which cooling air can flow into the expansion gaps.

Bisher wurden insbesondere die metallischen Halteelemente mittels unterhalb der Halteelemente eingeblasener Kühlluft gekühlt. Beim Anblasen der Halteelemente erfolgt jedoch die Sperrung der Spalte zwischen den keramischen Hitzeschildelementen nicht gleichmäßig. Dies führt dazu, dass für eine sichere Sperrung des Spaltes gegen das Eindringen des Heißgases mehr Kühlluft erforderlich ist, als theoretisch zur Sperrung des Spaltes nötig wäre. Des Weiteren ist aufgrund der Geometrie und der Anordnung der Halteelemente eine effektive Kühlung der dem Heißgas am ehesten ausgesetzten Halteabschnitte der Halteelemente erschwert.So far, in particular, the metallic holding elements have been cooled by means of injected below the holding elements cooling air. When blowing the holding elements, however, the blocking of the gap between the ceramic takes place Heat shield elements not even. This means that more cooling air is required for a safe blocking of the gap against the penetration of the hot gas, as would theoretically be necessary to block the gap. Furthermore, due to the geometry and the arrangement of the holding elements, effective cooling of the holding sections of the holding elements which are most likely to be exposed to the hot gas is made more difficult.

In der EP 1 302 723 A1 ist eine Brennkammerauskleidung mit Hitzeschildsteinen beschrieben, in welcher Strömungsbarrieren in den Dehnspalten zwischen den Hitzeschildsteinen angeordnet sind, um das Eindringen von Heißgas in die Dehnspalte zu vermindern. Die Hitzeschildsteine dieser Brennkammerauskleidung weisen an ihren Umfangsflächen Nuten auf, in welche eine im Spalt zwischen zwei Hitzeschildsteinen angeordnete Strömungsbarriere eingreift. Die Strömungsbarrieren werden mittels Halteankern im Dehnspalt fixiert.In the EP 1 302 723 A1 For example, a combustor liner having heat shield bricks is described in which flow barriers are disposed in the expansion nips between the heat shield bricks to reduce the penetration of hot gas into the expansion nips. The heat shield bricks of this combustion chamber lining have grooves on their peripheral surfaces into which a flow barrier arranged in the gap between two heat shield bricks engages. The flow barriers are fixed by means of retaining anchors in the expansion gap.

Die EP 1 260 767 A1 offenbart ein Spaltdichtelement zum Abdichten von Spalten zwischen benachbarten Hitzeschildelementen. Das Spaltdichtelement wird vor dem Einsetzen in den Spalt zusammengedrückt, so dass eine federnde Anlage an den Hitzeschildelementen eine gute Dichtung ermöglicht.The EP 1 260 767 A1 discloses a gap sealing element for sealing gaps between adjacent heat shield elements. The gap sealing element is compressed prior to insertion into the gap, so that a resilient contact with the heat shield elements enables a good seal.

Die EP 1 022 437 A1 offenbart ein Dichtelement zum Abdichten von Spalten, wobei das Dichtelement als Metalldichtfeder oder metallische Federdichtung ausgebildet ist.The EP 1 022 437 A1 discloses a sealing element for sealing gaps, wherein the sealing element is formed as a metal seal spring or metallic spring seal.

Gegenüber dem genannten Stand der Technik ist es eine Aufgabe der vorliegenden Erfindung, ein Spaltdichtelement mit einer alternativen Befestigungsmöglichkeit zur Verfügung zu stellen.Compared to the cited prior art, it is an object of the present invention to provide a gap sealing element with an alternative attachment option available.

Es ist eine weitere Aufgabe der vorliegenden Erfindung, einen Hitzeschild mit verbesserten Spaltdichtelementen zur Verfügung zu stellen.It is a further object of the present invention to provide a heat shield with improved gap sealing elements.

Die erste Aufgabe wird durch ein Spaltdichtelement nach Anspruch 1 und die zweite Aufgabe durch einen Hitzeschild nach Anspruch 8 gelöst.The first object is achieved by a gap sealing element according to claim 1 and the second object by a heat shield according to claim 8.

Ein erfindungsgemäßes Spaltdichtelement zum Abdichten von Spalten zwischen benachbarten Hitzeschildelementen umfasst mindestens einen federelastischen Abschnitt, welcher derart zum Ausüben einer Federkraft ausgestaltet ist, dass das in einen Spalt zwischen benachbarten Hitzeschildelementen eingesetzte Spaltdichtelement mittels Klemmsitz im Spalt gehalten wird, wobei der mindestens eine federelastische Abschnitt eine Wölbung aufweist, welche senkrecht zur Wirkrichtung der Federkraft zum Herstellen des Klemmsitzes vorspringt, wobei die Materialdicke im Bereich der Wölbung größer als in den übrigen Bereichen des Spaltdichtelements ist.A gap-sealing element according to the invention for sealing gaps between adjacent heat shield elements comprises at least one resilient section which is designed to exert a spring force such that the gap sealing element inserted into a gap between adjacent heat shield elements is held in the gap by means of a press fit, wherein the at least one resilient section forms a curvature which protrudes perpendicular to the direction of action of the spring force for producing the clamping seat, wherein the material thickness in the region of the curvature is greater than in the remaining areas of the gap sealing element.

Das erfindungsgemäße Spaltdichtelement kann insbesondere derart zum Abdichten von Spalten zwischen einander gegenüberliegenden und jeweils eine Nut aufweisenden Umfangsflächen benachbarter Hitzeschildelemente ausgestaltet sein, dass es in die Nuten der Umfangsflächen einander benachbarter Hitzeschildelemente den Spalt abdichtend derart einzusetzen ist, dass ein Teil von ihm in der Nut der einen Umfangsfläche und ein anderer Teil in der Nut der gegenüberliegenden Umfangsfläche angeordnet ist.The gap sealing element according to the invention can in particular be configured such for sealing gaps between opposing and each having a groove peripheral surfaces of adjacent heat shield elements that it is sealingly insert the gap in the grooves of the peripheral surfaces of adjacent heat shield elements such that a part of him in the groove of a peripheral surface and another part is disposed in the groove of the opposite peripheral surface.

Der mindestens eine federelastische Abschnitt weist eine Wölbung auf, welche in Richtung der Federkraft zum Herstellen des Klemmsitzes vorspringt. Die Wölbung kann dann einen Stützabschnitt bilden, der an einer Nutwand angreift, bspw. an der Nutwand, welche zu dem der Tragstruktur zugewandten Abschnitt des Hitzeschildelementes gehört, und das Spaltdichtelement gegen die gegenüberliegende Nutwand, d.h. gegen die Wand des der Gasturbinenbrennkammer zugewandten Abschnittes des Hitzeschildelementes drückt. Alternativ kann die Wölbung jedoch auch statt an der Nutwand, welche zu dem der Tragstruktur zugewandten Abschnitt des Hitzeschildelementes gehört, auch an der Tragstruktur angreifen. In der beschriebenen Ausgestaltung ist das Spaltdichtelement vorzugsweise derart ausgestaltet, dass es sich nicht bis zu den Nutböden der Nuten erstreckt. So verbleibt zwischen den Nutböden und dem Spaltdichtelement genügend Raum, damit das Spaltdichtelement bei einer Ausdehnung der keramischen Hitzeschildelemente aufgrund hoher Temperaturen nicht an die Nutböden anstößt. Spannungen in den Spaltdichtelementen bzw. in den keramischen Hitzeschildelementen aufgrund des Kontaktes zwischen den Enden der Spaltdichtelemente und den Nutböden können so vermieden werden.The at least one resilient portion has a curvature, which protrudes in the direction of the spring force for producing the clamping seat. The curvature can then form a support portion which acts on a groove wall, for example on the groove wall, which belongs to the support structure of the facing portion of the heat shield element, and the gap sealing element against the opposite groove wall, ie against the wall of the gas turbine combustor facing portion of the heat shield element suppressed. Alternatively, however, the curvature can also take place on the groove wall which faces the support structure of the portion of the heat shield element also belongs to the supporting structure. In the described embodiment, the gap sealing element is preferably designed such that it does not extend to the groove bottoms of the grooves. So remains between the groove bottoms and the gap sealing element enough space so that the gap sealing element does not abut the groove bottoms with an expansion of the ceramic heat shield elements due to high temperatures. Tensions in the gap sealing elements or in the ceramic heat shield elements due to the contact between the ends of the gap sealing elements and the groove bottoms can thus be avoided.

In einer alternativen Ausgestaltung weist der federelastische Abschnitt eine Wölbung auf, welche senkrecht zur Richtung der Federkraft zum Herstellen des Klemmsitzes vorspringt. Das Spaltdichtelement kann insbesondere zwei Stützabschnitte zum Abstützen an den Nutböden der Nuten umfassen, die durch den gewölbten federelastischen Abschnitt miteinander verbunden sind. Die Wölbung kann dabei insbesondere ein Profil besitzen, welches näherungsweise einem Kreisausschnitt mit einem Öffnungswinkel ϕ sowie einem Wölbungsradius R entspricht. Sie kann außerdem einen Wölbungshebel L aufweisen, welcher der Länge einer Strecke entspricht, die in senkrechter Richtung von einer gedachten Verbindungslinie ausgeht, welche diejenigen Punkte der Stützabschnitte miteinander verbindet, an denen bei Ausdehnung der Hitzeschildelemente der Kraftvektor einer das Spaltdichtelement komprimierenden Kraft angreift, und zu demjenigen Punkt der Wölbung führt, der am weitesten von der Verbindungslinie entfernt ist. Der Öffnungswinkel umfasst vorzugsweise einen Wert im Bereich von 50° bis 60°, der Radius R einen Wert im Bereich von 30 bis 40 mm und der Wölbungsradius L einen Wert im Bereich von 8 bis 10 mm. Außerdem ist die Materialdicke im Bereich der Wölbung größer als in den übrigen Bereichen des Spaltdichtelementes. Das Spaltdichtelement gemäß der soeben beschriebenen Ausgestaltung weist eine besonders hohe Dichtwirkung auf. Die Federkraft ist dabei so zu wählen, dass sie die für ein sicheres Klemmen notwendige Klemmkraft aufbringen kann, jedoch weder im Federelement noch in der Keramik unzulässige Spannungen entstehen, wenn sich die benachbarten keramischen Hitzeschildelemente aufgrund hoher Temperaturen ausdehnen und sich die Stützabschnitte des Spaltdichtelementes aufeinander zu bewegen.In an alternative embodiment, the resilient portion has a curvature which protrudes perpendicular to the direction of the spring force for producing the clamping seat. The gap-sealing element may in particular comprise two support sections for supporting on the groove bottoms of the grooves, which are connected to one another by the curved elastic section. The curvature can in particular have a profile which approximately corresponds to a circular section with an opening angle φ and a curvature radius R. It may also have a curvature lever L which corresponds to the length of a path extending in a perpendicular direction from an imaginary connecting line connecting those points of the support sections to which the force vector of a force compressing the gap sealing element engages as the heat shield elements expand leading to the point of curvature furthest from the connecting line. The opening angle preferably comprises a value in the range of 50 ° to 60 °, the radius R a value in the range of 30 to 40 mm and the curvature radius L a value in the range of 8 to 10 mm. In addition, the material thickness in the region of the curvature is greater than in the other areas of the gap sealing element. The gap sealing element according to the embodiment just described has a particularly high sealing effect. The spring force is to be chosen so that they However, the clamping force necessary for a secure clamping can apply, but neither in the spring element nor in the ceramic impermissible stresses arise when the adjacent ceramic heat shield elements expand due to high temperatures and the support sections of the gap sealing element to move towards each other.

Im Vergleich zu den in EP 1 302 723 A1 beschriebenen Strömungsbarrieren weisen die erfindungsgemäßen Spaltdichtelemente eine alternative Form der Befestigung auf. Während die Strömungsbarrieren im Stand der Technik mittels Halteankern befestigt werden müssen, brauchen die erfindungsgemäßen Spaltdichtelemente lediglich in die Spalte und/oder die Nuten zwischen den Hitzeschildelementen eingesetzt zu werden. In den Spalten und/oder in den Nuten werden sie dann mittels Klemmsitz gehalten. Halteanker und entsprechende Gegenstücke zum Fixieren der Halteanker sind daher beim erfindungsgemäßen Spaltdichtelement nicht nötig.Compared to the in EP 1 302 723 A1 flow barriers described inventive gap sealing elements have an alternative form of attachment. While the flow barriers in the prior art must be secured by means of retaining anchors, the gap sealing elements according to the invention need only be inserted into the gaps and / or the grooves between the heat shield elements. In the columns and / or in the grooves, they are then held by means of a press fit. Retaining anchors and corresponding counterparts for fixing the retaining anchor are therefore not necessary in the gap sealing element according to the invention.

Die erfindungsgemäßen Spaltdichtelemente werden zum Vermeiden des Kontaktes zwischen Heißgas und den Halteelementen oberhalb der Halteelemente in die Spalte bzw. Nuten eingesetzt. Die Federkraft der federnden Abschnitte ist dabei derart gewählt, dass sie die für einen sicheren Klemmsitz notwendige Klemmkraft zur Verfügung stellt. Außerdem sind die Abmessungen des Spaltdichtelementes derart gewählt, dass die thermische Dehnung der Hitzeschildelemente nicht behindert wird, sodass weder im Spaltdichtelement noch in der Keramik unzulässige Spannungen aufgrund der Verringerung der Dehnspaltabmessungen entstehen.The gap sealing elements according to the invention are used to avoid the contact between the hot gas and the holding elements above the holding elements in the gaps or grooves. The spring force of the resilient portions is chosen such that it provides the necessary clamping force for a secure clamping fit available. In addition, the dimensions of the gap sealing element are chosen such that the thermal expansion of the heat shield elements is not hindered, so that neither in the gap sealing element nor in the ceramic undue stresses caused by the reduction of the expansion gap dimensions.

Im Vergleich zu den in EP 1 302 723 A1 beschriebenen Strömungsbarrieren weisen die erfindungsgemäßen Spaltdichtelemente eine alternative Form der Befestigung auf. Während die Strömungsbarrieren im Stand der Technik mittels Halteankern befestigt werden müssen, brauchen die erfindungsgemäßen Spaltdichtelemente lediglich in die Spalte und/oder die Nuten zwischen den Hitzeschildelementen eingesetzt zu werden. In den Spalten und/oder in den Nuten werden sie dann mittels Klemmsitz gehalten. Halteanker und entsprechende Gegenstücke zum Fixieren der Halteanker sind daher beim erfindungsgemäßen Spaltdichtelement nicht nötig.Compared to the in EP 1 302 723 A1 flow barriers described inventive gap sealing elements have an alternative form of attachment. While the flow barriers in the prior art must be fastened by means of retaining anchors, the gap sealing elements according to the invention need only in the gaps and / or the grooves to be inserted between the heat shield elements. In the columns and / or in the grooves, they are then held by means of a press fit. Retaining anchors and corresponding counterparts for fixing the retaining anchor are therefore not necessary in the gap sealing element according to the invention.

Die erfindungsgemäßen Spaltdichtelemente werden zum Vermeiden des Kontaktes zwischen Heißgas und den Halteelementen oberhalb der Halteelemente in die Spalte bzw. Nuten eingesetzt. Die Federkraft der federnden Abschnitte ist dabei derart gewählt, dass sie die für einen sicheren Klemmsitz notwendige Klemmkraft zur Verfügung stellt. Außerdem sind die Abmessungen des Spaltdichtelementes derart gewählt, dass die thermische Dehnung der Hitzeschildelemente nicht behindert wird, sodass weder im Spaltdichtelement noch in der Keramik unzulässige Spannungen aufgrund der Verringerung der Dehnspaltabmessungen entstehen.The gap sealing elements according to the invention are used to avoid the contact between the hot gas and the holding elements above the holding elements in the gaps or grooves. The spring force of the resilient portions is chosen such that it provides the necessary clamping force for a secure clamping fit available. In addition, the dimensions of the gap sealing element are chosen such that the thermal expansion of the heat shield elements is not hindered, so that neither in the gap sealing element nor in the ceramic undue stresses caused by the reduction of the expansion gap dimensions.

Ein erfindungsgemäßer Hitzeschild an einer Tragstruktur zum Schutz der Tragstruktur und/oder einer die Tragstruktur umfassenden oder mit der Tragstruktur verbundenen Wand gegen ein Heißgas umfasst eine Anzahl unter Spaltbelassung aneinander grenzender Hitzeschildelemente, die insbesondere als keramische Hitzeschildelemente ausgestaltet sein können. Erfindungsgemäß sind in den Spalten zwischen einander gegenüberliegenden Hitzeschildelementen erfindungsgemäße Spaltdichtelemente angeordnet.A heat shield according to the invention on a support structure for protecting the support structure and / or a wall enclosing the support structure or connected to the support structure against a hot gas comprises a number of heat shield elements adjoining each other by gap-sealing, which can be configured in particular as ceramic heat shield elements. According to the invention gap sealing elements according to the invention are arranged in the gaps between opposing heat shield elements.

Mit dem erfindungsgemäßen Hitzeschild kann der Kühl-/Sperrluftverbrauch einer Gasturbinenbrennkammer verringert werden. Dadurch wird die Verbrennungstemperatur abgesenkt und die thermische Spannungsbelastung in den keramischen Hitzeschilden vermindert. Als Folge werden die NOx-Emissionen sowie die Beanspruchung der keramischen Hitzeschilde verringert.With the heat shield according to the invention, the cooling / sealing air consumption of a gas turbine combustion chamber can be reduced. This lowers the combustion temperature and reduces the thermal stress in the ceramic heat shields. As a result, the Reduced NO x emissions and the stress on the ceramic heat shields.

Es lassen sich daher entweder bei gleicher Leistung die Nox-Emissionen verringern oder die Leistung und der Wirkungsgrad bei gleich bleibenden Emissionen erhöhen. Aufgrund der Verringerung der thermischen Belastung der Hitzeschildelemente ergeben sich verringerte Austauschraten der Elemente sowie eine mögliche Verlängerung der Inspektionsintervalle der Brennkammer. Außerdem wirkt sich die Verringerung der Belastung auch positiv auf die Dauer von Inspektionen aus.It is therefore possible either to reduce No x emissions or to increase power and efficiency while maintaining the same emissions. Due to the reduction of the thermal load of the heat shield elements results in reduced exchange rates of the elements and a possible extension of the inspection intervals of the combustion chamber. In addition, reducing the burden also has a positive effect on the duration of inspections.

In einer Ausgestaltung des erfindungsgemäßen Hitzeschildes können die Hitzeschildelemente die Dehnspalte begrenzende und mit Nuten versehene Umfangsflächen aufweisen, wobei ein Spaltdichtelement einen Spalt abdichtend jeweils derart in die Nuten der den Spalt begrenzenden Umfangsflächen einzusetzen ist, dass ein Teil von ihm in der Nut der einen Umfangsfläche und ein anderer Teil in der Nut der gegenüberliegenden Umfangsfläche angeordnet ist.In one embodiment of the heat shield according to the invention, the heat shield elements may have the expansion gaps bounding and grooved peripheral surfaces, wherein a gap sealing element is a gap sealingly insert each such into the grooves of the gap bounding peripheral surfaces, that a part of him in the groove of a peripheral surface and another part is arranged in the groove of the opposite peripheral surface.

In einer weiteren Ausgestaltung des erfindungsgemäßen Hitzeschildes wirkt die den Klemmsitz herstellende Federkraft zwischen der Tragstruktur und jeweils der heißseitigen Nutwand der Nuten In einer alternativen Ausgestaltung wirkt die Federkraft zwischen den kaltseitigen Nutwänden und den heißseitigen Nutwänden, insbesondere den kaltseitigen Nutwänden und den heißseitigen Nutwänden derselben Nut. In noch einer alternativen Ausgestaltung wirkt die den Klemmsitz herstellende Federkraft zwischen den Nutböden zweier einander gegenüberliegender Nuten. Die letzten beiden Alternativen ermöglichen eine günstige Kühlluftströmung im Dehnspalt, da kein Abschnitt des Spaltdichtelementes in den zwischen der Tragstruktur und den Nuten gelegenen Bereich des Dehnspaltes einzugreifen braucht.In a further embodiment of the heat shield according to the invention, the spring force producing the clamping seat between the support structure and the hot side groove wall of the grooves acts in an alternative embodiment, the spring force between the cold side groove walls and the hot side groove walls, in particular the cold side groove walls and the hot side groove walls of the same groove. In yet an alternative embodiment, the spring force producing the clamping seat acts between the groove bottoms of two opposing grooves. The last two alternatives allow a favorable cooling air flow in the expansion gap, since no portion of the gap sealing element needs to intervene in the region of the expansion gap located between the support structure and the grooves.

In einer Weiterbildung des erfindungsgemäßen Hitzeschildes weist die Tragstruktur Kühlluftöffnungen zum Zuführen eines Kühlfluids in Richtung auf die Spaltdichtelemente auf. Durch die Kühlluftöffnungen können die Spaltdichtelemente mit Prallstrahlen angeblasen werden, um sie zu kühlen. Auf diese Weise kann ein Verzundern oder Schmelzen der metallischen Spaltdichtelemente vermieden werden. Die abströmende Prallluft dient zusätzlich zur konvektiven Kühlung.In a development of the heat shield according to the invention, the support structure has cooling air openings for supplying a cooling fluid in the direction of the gap sealing elements. Through the cooling air openings, the gap sealing elements can be blown with impact rays to cool them. In this way, a scaling or melting of the metallic gap sealing elements can be avoided. The outflowing impingement air additionally serves for convective cooling.

Weitere Merkmale, Eigenschaften und Vorteile der vorliegenden Erfindung ergeben sich aus der nachfolgenden Beschreibung von Ausführungsbeispielen unter Bezugnahme auf die beiliegenden Figuren.Further features, properties and advantages of the present invention will become apparent from the following description of embodiments with reference to the accompanying figures.

Fig. 1 zeigt ein erstes Ausführungsbeispiel für das erfindungsgemäße Spaltdichtelement. Fig. 1 shows a first embodiment of the inventive gap sealing element.

Fig. 2 zeigt das Spaltdichtelement aus Figur 1 im in einen Hitzeschild eingebauten Zustand. Fig. 2 shows the gap sealing element FIG. 1 in the built-in heat shield state.

Fig. 3 zeigt ein zweites Ausführungsbeispiel für das erfindungsgemäße Spaltdichtelement. Fig. 3 shows a second embodiment of the inventive gap sealing element.

Fig. 4 zeigt das Spaltdichtelement aus Figur 3 im in einen Hitzeschild eingebauten Zustand. Fig. 4 shows the gap sealing element FIG. 3 in the built-in heat shield state.

Fig. 5 zeigt ein drittes Ausführungsbeispiel für das erfindungsgemäße Spaltdichtelement. Fig. 5 shows a third embodiment of the inventive gap sealing element.

Fig. 6 zeigt das Spaltdichtelement aus Figur 5 im in einen Hitzeschild eingebauten Zustand. Fig. 6 shows the gap sealing element FIG. 5 in the built-in heat shield state.

Fig. 7 zeigt ein viertes Ausführungsbeispiel für das erfindungsgemäße Spaltdichtelement. Fig. 7 shows a fourth embodiment of the inventive gap sealing element.

Fig. 8 zeigt das Spaltdichtelement aus Figur 7 im in einen Hitzeschild eingebauten Zustand. Fig. 8 shows the gap sealing element FIG. 7 in the built-in heat shield state.

Fig. 9 zeigt ein fünftes Ausführungsbeispiel für das erfindungsgemäße Spaltdichtelement Fig. 9 shows a fifth embodiment of the inventive gap sealing element

Fig. 10 zeigt das Spaltdichtelement aus Figur 9 im in einen Hitzeschild eingebauten Zustand. Fig. 10 shows the gap sealing element FIG. 9 in the built-in heat shield state.

Fig. 11 zeigt die Kühlluftströmung entlang eines keramischen Hitzeschildelementes bei Verwendung eines erfindungsgemäßen Spaltdichtelementes. Fig. 11 shows the cooling air flow along a ceramic heat shield element using a gap sealing element according to the invention.

Figur 1 zeigt ein erstes Ausführungsbeispiel für das erfindungsgemäße Spaltdichtelement in einer perspektivischen Ansicht. Das Spaltdichtelement 10 umfasst eine metallische Dichtplatte 12 und einen gewölbten Metallstreifen 14, dessen beiden Enden 15 an der Dichtplatte 12 befestigt sind, bspw. indem sie mit der Dichtplatte 12 verschweißt sind. Der gewölbte Metallstreifen 14 bildet einen federelastischen Vorsprung, welcher nach dem Einbau des Spaltdichtelementes 10 in einen Hitzeschild für einen Klemmsitz des Spaltdichtelementes 10 sorgt. FIG. 1 shows a first embodiment of the inventive gap sealing element in a perspective view. The gap sealing element 10 comprises a metallic sealing plate 12 and a curved metal strip 14, whose two ends 15 are fastened to the sealing plate 12, for example by being welded to the sealing plate 12. The curved metal strip 14 forms a resilient projection, which provides for the installation of the gap sealing element 10 in a heat shield for a clamping fit of the gap sealing element 10.

Eine alternative Ausführung des in Fig. 1 gezeigten Dichtelementes zeigt Fig. 1a. Beim in Fig. 1a dargestellten Dichtelement 10a ist der gewölbte Metallstreifen 14a statt an seinen Enden 15a in der Mitte 17a mit der Dichtplatte 12a verbunden. Seine freien Enden 15a bilden Federelemente, welche nach dem Einbau des Spaltdichtelementes 10a in einen Hitzeschild für einen Klemmsitz des Spaltdichtelementes 10a sorgen.An alternative embodiment of the in Fig. 1 shown sealing element shows Fig. 1a , When in Fig. 1a illustrated sealing element 10a is the curved metal strip 14a instead of connected at its ends 15a in the middle 17a with the sealing plate 12a. Its free ends 15a form spring elements which, after installation of the gap sealing element 10a, provide a heat shield for a clamping seat of the gap sealing element 10a.

Eine weitere alternative Ausführung des in Fig. 1 gezeigten Dichtelementes zeigt Fig. 1b. Beim in Fig. 1b dargestellten Dichtelement 10b ist der gewölbte Metallstreifen 14b wie der Metallstreifen 14 in Fig. 1 geformt. Im Unterschied zum Metallstreifen 14 ist er jedoch nicht an beiden Enden 15b, 15c mit der Dichtplatte 12b verschweißt, sondern nur an einem Ende 15b. Das andere Ende 15c ist lose und kann an der Dichtplatte 12b entlanggleiten. Der gewölbte Metallstreifen 14b bildet wie in Fig. 1 einen federelastischen Vorsprung, welcher nach dem Einbau des Spaltdichtelementes 10b in einen Hitzeschild für einen Klemmsitz des Spaltdichtelementes 10b sorgt.Another alternative embodiment of the in Fig. 1 shown sealing element shows Fig. 1b , When in Fig. 1b illustrated sealing element 10b is the curved metal strip 14b as the metal strip 14 in Fig. 1 shaped. In contrast to the metal strip 14, however, it is not welded at both ends 15b, 15c to the sealing plate 12b, but only at one End 15b. The other end 15c is loose and can slide along the sealing plate 12b. The curved metal strip 14b forms as in Fig. 1 a resilient projection, which provides after the installation of the gap sealing element 10b in a heat shield for a clamping fit of the gap sealing element 10b.

Statt eines einstückigen Metallstreifens 14 bzw. 14a können auch zwei getrennte Metallstreifen vorhanden sein, die jeweils einer Hälfte des Metallstreifens 14 bzw. des Metallstreifens 14a entsprechen und am Rand oder in der Mitte der Dichtplatte 12 bzw. 12a angeschweißt sind.Instead of a one-piece metal strip 14 or 14a, two separate metal strips may be present, which correspond to one half of the metal strip 14 and the metal strip 14a and are welded to the edge or in the middle of the sealing plate 12 and 12a.

Figur 2 zeigt das Spaltdichtelement 10 des ersten Ausführungsbeispiels im in einen Hitzeschild eingebauten Zustand. Die Figur zeigt ein keramisches Hitzeschildelement 16, welches mittels metallischer Elementhalter 18 an der Tragstruktur 20 einer Gasturbinenbrennkammer befestigt ist. Das Hitzeschildelement 16 weist eine der Tragstruktur 20 zuzuwendende Kaltseite 22 sowie eine im Heißgas in der Gasturbinenbrennkammer zuzuwendende Heißseite 24 auf. Zwischen der Heißseite 24 und der Kaltseite 22 erstrecken sich erste Umfangsflächen 26 und zweite Umfangsflächen 28, wobei sich die ersten Umfangsflächen von den zweiten Umfangsflächen dadurch unterscheiden, dass sie eine Nut 30 aufweisen, in welcher ein Eingriffsabschnitt (in der Figur nicht zu erkennen) der Elementhalter 18 zum Halten des keramischen Hitzeschildelementes 16 eingreift. Die zweiten Umfangsflächen 28 sind dagegen in der Regel nutfrei ausgebildet. FIG. 2 shows the gap sealing element 10 of the first embodiment in the installed state in a heat shield. The figure shows a ceramic heat shield element 16, which is fastened by means of metallic element holder 18 to the support structure 20 of a gas turbine combustor. The heat shield element 16 has a cold side 22, which faces the support structure 20, and a hot side 24, which faces the hot gas in the gas turbine combustion chamber. Between the hot side 24 and the cold side 22 extend first peripheral surfaces 26 and second peripheral surfaces 28, wherein the first peripheral surfaces of the second peripheral surfaces differ in that they have a groove 30 in which an engagement portion (not visible in the figure) of Element holder 18 for holding the ceramic heat shield element 16 engages. On the other hand, the second circumferential surfaces 28 are generally groove-free.

Zum Fixieren des keramischen Hitzeschildelementes 16 an der Tragstruktur weisen die metallischen Halteelemente 18 jeweils neben dem Eingriffsabschnitt zum Eingriff in die Nut 30 des Hitzeschildelementes 16 einen Befestigungsabschnitt (nicht dargestellt) zum Einsetzen in eine Nut 32 der Tragstruktur 20 auf. In der Nut 32 sind die Befestigungsabschnitte dann beispielsweise mittels Schrauben fixiert, insbesondere am Boden der Nut 32.For fixing the ceramic heat shield element 16 to the support structure, the metallic support elements 18 each have, in addition to the engagement portion for engagement with the groove 30 of the heat shield member 16, a mounting portion (not shown) for insertion into a groove 32 of the support structure 20. In the groove 32, the mounting portions are then fixed, for example by means of screws, in particular at the bottom of the groove 32nd

Im Hitzeschild sind die keramischen Hitzeschildelemente 16 derart flächendeckend angeordnet, dass sie mit ihren Umfangsflächen 26, 28 aneinander grenzen, wobei zwischen den aneinandergrenzenden Umfangsflächen Dehnspalte verbleiben, damit sich die Hitzeschildelemente 16 beim Übergang vom kalten in den heißen (Betriebs-) Zustand ausdehnen können. Die Dimension der Dehnspalte ist dabei so bemessen, dass benachbarte Hitzeschildelemente 16 selbst im heißesten Zustand nicht aneinander stoßen, um so Spannungen, welche zu Rissbildungen führen könnten, zu vermeiden. Die von den ersten Umfangsflächen 26 begrenzten Dehnspalte erstrecken sich bei radialsymmetrischen Brennkammern in der Regel - aber nicht notwendigerweise - in Umfangsrichtung der Brennkammer und die von den zweiten Umfangsflächen begrenzten Dehnspalte in Axialrichtung der Brennkammer. In Figur 2 ist der Übersichtlichkeit halber nur ein Hitzeschildelement 16 des Hitzeschildes dargestellt.In the heat shield, the ceramic heat shield elements 16 are arranged in such a comprehensive manner that they adjoin each other with their peripheral surfaces 26, wherein between the adjacent peripheral surfaces Dehnspalte remain so that the heat shield elements 16 can extend the transition from cold to hot (operating) state. The dimension of the expansion column is dimensioned so that adjacent heat shield elements 16 do not abut each other even in the hottest state, so as to avoid stresses that could lead to cracking. The expansion gaps bounded by the first peripheral surfaces 26 generally extend in the case of radially symmetrical combustion chambers, but not necessarily in the circumferential direction of the combustion chamber and the expansion gaps bounded by the second peripheral surfaces in the axial direction of the combustion chamber. In FIG. 2 For the sake of clarity, only one heat shield element 16 of the heat shield is shown.

In denjenigen Dehnspalten des Hitzeschildes, die durch zwei erste Umfangsflächen 26 begrenzt werden, sind die erfindungsgemäßen Spaltdichtelemente 10 angeordnet, um zu verhindern, dass Heißgas von der Heißseite 24 aus durch die Dehnspalte in Richtung auf die Tragstruktur 20 strömen kann. Ein Abschnitt der Dichtplatte 12 der Spaltdichtelemente 10 greift, wie in Figur 2 dargestellt, dabei in die Nut 30 einer ersten den Dehnspalt begrenzenden Umfangsfläche 26 eines keramischen Hitzeschildelementes 16 ein, wohingegen ein weiterer Abschnitt der Dichtplatte 12 in die Nut der gegenüberliegenden ersten Umfangsfläche eines weiteren keramischen Hitzeschildelementes (nicht dargestellt) eingreift. Das Spaltdichtelement 12 ist mittels Klemmsitz in seiner Position fixiert. Dabei stützt sich der gewölbte Metallstreifen 14 an der Tragstruktur 20 ab, um die Dichtplatte mittels seiner Federkraft gegen die Nutwände 33 der heißseitigen Abschnitte der keramischen Hitzeschildelemente 16 zu drücken, so dass ein Klemmsitz zwischen der Tragstruktur 20 einerseits und den Nutwänden 33 andererseits entsteht.In those expansion gaps of the heat shield, which are delimited by two first peripheral surfaces 26, the gap sealing elements 10 according to the invention are arranged to prevent hot gas from flowing from the hot side 24 through the expansion gaps in the direction of the support structure 20. A portion of the sealing plate 12 of the gap sealing elements 10 engages, as in FIG. 2 shown, while in the groove 30 a first expansion gap bounding peripheral surface 26 of a ceramic heat shield element 16, whereas a further portion of the sealing plate 12 in the groove of the opposite first peripheral surface of another ceramic heat shield element (not shown) engages. The gap sealing element 12 is fixed in its position by means of a press fit. In this case, the curved metal strip 14 is supported on the support structure 20 to the sealing plate by means of its spring force against the groove walls 33rd the hot side portions of the ceramic heat shield elements 16 to press, so that a clamping fit between the support structure 20 on the one hand and the groove walls 33 on the other hand arises.

Die Abmessungen der Dichtplatte 12 sind so gewählt, dass die Seitenflächen 13 der Dichtplatte 12 die Nutboden 31 der Nuten 30 nicht berühren, selbst wenn die Hitzeschildelemente 16 ihre größte thermische Ausdehnung aufweisen. Dadurch kann verhindert werden, dass das Spaltdichtelement oder die keramische Hitzeschildelemente 16 beschädigt werden.The dimensions of the sealing plate 12 are chosen so that the side surfaces 13 of the sealing plate 12, the groove bottom 31 of the grooves 30 do not touch, even if the heat shield elements 16 have their greatest thermal expansion. This can prevent the gap seal member or the ceramic heat shield members 16 from being damaged.

Da das Spaltdichtelement 10 aus Metall hergestellt ist, kann es den Temperaturen des von der Brennkammer durch die Dehnspalte zur Dichtplatte 12 strömenden Heißgases nicht ohne weiteres ausgesetzt werden. Zur Prallluftkühlung sind in der Tragstruktur 20 daher Kühlbohrungen 34 vorhanden, durch die die Dichtplatte 12 mit Kühlluft angeblasen wird. Die angeblasene Kühlluft strömt dabei entlang der Dichtplatte 12 in Richtung auf die zwischen den zweiten Umfangsflächen 28 vorhandenen Dehnspalte und tritt durch diese in die Brennkammer der Gasturbine ein, wobei sie die zwischen den zweiten Umfangsflächen 28 befindlichen Dehnspalte gegen den Eintritt von Heißgas absperrt. Die Kühlluftströmung wird später mit Bezug auf Fig. 11 näher erläutert werden.Since the gap seal member 10 is made of metal, it can not easily be exposed to the temperatures of the hot gas flowing from the combustion chamber through the expansion gaps to the seal plate 12. For impact air cooling, cooling bores 34 are therefore present in the support structure 20, through which the sealing plate 12 is blown with cooling air. The blown cooling air flows along the sealing plate 12 in the direction of the existing between the second peripheral surfaces 28 Dehnspalte and enters through this into the combustion chamber of the gas turbine, wherein it blocks the expansion gaps located between the second peripheral surfaces 28 against the entry of hot gas. The cooling air flow will be discussed later with reference to FIG Fig. 11 be explained in more detail.

Ein zweites Ausführungsbeispiel für das erfindungsgemäße Spaltdichtelement ist in Figur 3 dargestellt. Das Spaltdichtelement 110 umfasst wie das in Figur 1 dargestellte Spaltdichtelement 10 eine Dichtplatte 112. Im Unterschied zum ersten Ausführungsbeispiel sind an die Dichtplatte 112 jedoch zwei gewölbte Metallstreifen 114, welche federelastisch ausgebildet sind und eine Federkraft für einen Klemmsitz des Spaltdichtelementes 110 zur Verfügung stellen, mit Abstand nebeneinander angeschweißt.A second embodiment of the inventive gap sealing element is in FIG. 3 shown. The gap sealing element 110 comprises as in FIG. 1 In contrast to the first embodiment, however, two arched metal strips 114, which are resilient and provide a spring force for a clamping fit of the gap sealing element 110, are welded to the sealing plate 112 at a distance next to one another.

Figur 4 zeigt das Spaltdichtelement 110 des zweiten Ausführungsbeispiels nach dem Einbau in einen keramischen Hitzeschild, der bis auf das Spaltdichtelement 110 im Wesentlichen dem mit Bezug auf Fig. 2 beschriebenen Hitzeschild entspricht. Die keramischen Hitzeschildelemente 16, die Tragstruktur 20 und die Halteelemente 18 unterscheiden sich nicht von den Hitzeschildelementen 16, der Tragstruktur 20 und den Halteelementen 18 des mit Bezug auf das erste Ausführungsbeispiel beschriebenen Hitzeschildes. Strukturen, die sich nicht von den in Figur 2 dargestellten Strukturen unterscheiden sind daher mit denselben Bezugszeichen wie in Figur 2 bezeichnet. FIG. 4 shows the gap sealing element 110 of the second embodiment after installation in a ceramic heat shield, with the exception of the gap sealing element 110 substantially with reference to with reference to Fig. 2 corresponds to described heat shield. The ceramic heat shield members 16, the support structure 20, and the support members 18 are not different from the heat shield members 16, the support structure 20, and the support members 18 of the heat shield described with respect to the first embodiment. Structures that are different from those in FIG. 2 Different structures are therefore distinguished by the same reference numerals as in FIG. 2 designated.

Ebenso wie beim ersten Ausführungsbeispiel ist das Spaltdichtelement 110 derart in die Nuten 30 einander gegenüberliegender Umfangsflächen 26 eingesetzt, dass es gegen die Nutwände 33 der heißseitigen Abschnitte der keramischen Hitzeschildelemente 16 gedrückt wird und die Nutböden 31 nicht berührt. Im Gegensatz zum ersten Ausführungsbeispiel stützen sich die gewölbten Metallstreifen 114 jedoch nicht an der Tragstruktur 20 ab, um den Klemmsitz herzustellen. Stattdessen stützen sie sich an den Nutwände 35 der kaltseitigen Abschnitte der Hitzeschildelemente 16 ab, um mittels ihrer Federkraft die Dichtplatte 112 gegen die Nutwände 33 der heißseitigen Abschnitte der keramischen Hitzeschildelemente 16 zu drücken. Aufgrund der Federkraft wird das Spaltdichtelement 110 sicher in den Nuten 30 der keramischen Hitzeschildelemente 16 mittels Klemmsitz, welcher zwischen den Nutwänden 35 und den Nutwänden 33 wirkt, fixiert.
Auch im zweiten Ausführungsbeispiel wird das Spaltdichtelement 110 mit Kühlluft angeblasen, die durch Kühlluftbohrungen 134 in der Tragstruktur austritt. Da die gewölbten Metallstreifen 114 im zweiten Ausführungsbeispiel die Kühlluftströmung durch die Dehnspalte weniger behindern als der sich bis zur Tragstruktur 20 erstreckende Metallstreifen 14 des ersten Ausführungsbeispiels, kann der Kühlluftverbrauch im Vergleich zum ersten Ausführungsbeispiel weiter vermindert werden.As in the first embodiment, the gap seal member 110 is inserted into the grooves 30 of opposite circumferential surfaces 26 so as to be pressed against the groove walls 33 of the hot side portions of the ceramic heat shield members 16 and does not contact the groove bottoms 31. However, unlike the first embodiment, the domed metal strips 114 do not abut the support structure 20 to make the press fit. Instead, they are supported on the groove walls 35 of the cold side portions of the heat shield members 16 to press the sealing plate 112 against the groove walls 33 of the hot side portions of the ceramic heat shield members 16 by their spring force. Due to the spring force, the gap sealing element 110 is securely fixed in the grooves 30 of the ceramic heat shield elements 16 by means of a clamping fit, which acts between the groove walls 35 and the groove walls 33.
Also in the second embodiment, the gap sealing element 110 is blown with cooling air, which exits through cooling air holes 134 in the support structure. Since the curved metal strips 114 in the second embodiment, the cooling air flow through the Dehnspalte less hinder than the up to the support structure 20 extending metal strip 14 of the first embodiment, the Cooling air consumption in comparison to the first embodiment can be further reduced.

Ein drittes Ausführungsbeispiel für das erfindungsgemäße Spaltdichtelement ist in den Figuren 5 und 6 dargestellt. Figur 5 zeigt das Spaltdichtelement 210 des dritten Ausführungsbeispiels in einer perspektivischen Darstellung, während Figur 6 das Spaltdichtelement aus Figur 5 nach dem Einbau in einen keramischen Hitzeschild darstellt. Der keramische Hitzeschild entspricht dabei bis auf das Spaltdichtelement 210 im Wesentlichen dem mit Bezug auf das erste Ausführungsbeispiel beschriebenen Hitzeschild. Strukturen des Hitzeschildes, die denen mit Bezug auf Fig. 2 beschriebenen Strukturen entsprechen, sind daher mit denselben Bezugszeichen wie in Fig. 2 bezeichnet.A third embodiment of the inventive gap sealing element is in the Figures 5 and 6 shown. FIG. 5 shows the gap sealing element 210 of the third embodiment in a perspective view, while FIG. 6 the gap sealing element FIG. 5 after installation in a ceramic heat shield represents. The ceramic heat shield in this case corresponds, with the exception of the gap sealing element 210, essentially to the heat shield described with reference to the first exemplary embodiment. Structures of the heat shield related to those Fig. 2 are therefore denoted by the same reference numerals as in FIG Fig. 2 designated.

Das Spaltdichtelement 210 des dritten Ausführungsbeispiels entspricht im Wesentlichen einem Dichtblech 214, das ein Profil mit in einer ersten Ausdehnungsrichtung A gebogenem Profilverlauf und in einer zweiten, zur ersten Ausdehnungsrichtung senkrechten Ausdehnungsrichtung B geradem Profilverlauf aufweist. Es weist in Ausdehnungsrichtung A Enden 212 auf, die beide in dieselbe Richtung umgebogen sind und deren Biegung einen in etwa halbkreisförmigen Verlauf besitzen. Die umgebogenen Enden 212 bilden Stützabschnitte, welche im eingebauten Zustand (siehe Figur 6) großflächig an den Nutböden 31 der Nuten 30 einander gegenüberliegender Umfangsflächen 26 anliegen. Die Stützabschnitte 212 sind in Ausdehnungsrichtung A über einem gewölbten Federabschnitt 214 miteinander verbunden. Der gewölbte Federabschnitt 214 weist einen Querschnitt auf, der im Wesentlichen einen Kreisausschnitt mit dem Radius R und dem Öffnungswinkel ϕ entspricht, wobei die Krümmung gegenüber der Krümmung der Biegung der Stützabschnitte 212 ein anderes Vorzeichen besitzt.The gap-sealing element 210 of the third exemplary embodiment substantially corresponds to a sealing plate 214 which has a profile with a profile course bent in a first expansion direction A and a straight profile profile in a second expansion direction B perpendicular to the first expansion direction. It has in the direction of extension A ends 212, which are both bent in the same direction and whose bending have an approximately semicircular course. The bent ends 212 form support sections, which in the installed state (see FIG. 6 ) over a large area on the groove bottoms 31 of the grooves 30 abut each other opposite peripheral surfaces 26. The support sections 212 are connected to one another in the expansion direction A via a curved spring section 214. The domed spring portion 214 has a cross-section that substantially corresponds to a circular cutout with the radius R and the opening angle φ, wherein the curvature opposite to the curvature of the bend of the support portions 212 has a different sign.

Das Spaltdichtelement 210, das aus einem Metallblech mit einer konstanten Dicke von ca. 1 mm hergestellt ist, weist aufgrund seines gewölbten Federabschnittes 214 federelastische Eigenschaften auf. Wenn das Spaltdichtelement 210 in einander gegenüberliegenden Nuten von Hitzeschildelementen 16 eingesetzt ist, so führt die Federkraft des Federabschnittes 214 dazu, dass die Stützabschnitte 212 gegen die Nutböden 31 der Nuten 30 gedrückt werden, sodass das Spaltdichtelement 210 mit Klemmsitz in den Nuten fixiert ist. Wenn sich die Hitzeschildelemente 16 aufgrund hoher Temperaturen ausdehnen und sich daher die Nutböden 31 der Nuten 30 aufeinander zu bewegen, so kann das Spaltdichtelement 210 aufgrund der federelastischen Eigenschaften des Federabschnittes 214 komprimiert werden. Ziehen sich die Hitzeschildelemente 16 beim Abkühlen wieder zusammen, sodass sich die Nutböden 31 wieder voneinander entfernen, sorgt die Federkraft des Federabschnittes 214 für eine Expansion des Spaltdichtelementes, so dass die Stützabschnitte 212 auch beim Abkühlen immer gegen die Nutböden 31 gedrückt bleiben und der Klemmsitz immer sicher erhalten bleibt.The gap sealing element 210, which is made of a metal sheet with a constant thickness of about 1 mm, has due to its curved spring portion 214 spring elastic properties. When the gap seal member 210 is inserted in opposing grooves of heat shield members 16, the spring force of the spring portion 214 causes the support portions 212 to be pressed against the groove bottoms 31 of the grooves 30, so that the gap seal member 210 is press-fitted into the grooves. When the heat shield elements 16 expand due to high temperatures and therefore the groove bottoms 31 of the grooves 30 move toward one another, the gap sealing element 210 can be compressed due to the spring-elastic properties of the spring section 214. If the heat shield elements 16 contract again on cooling, so that the groove bottoms 31 move away from each other again, the spring force of the spring section 214 causes the gap sealing element to expand, so that the support sections 212 always remain pressed against the groove bottoms 31 during cooling and the clamping fit always safely preserved.

Die Federelastizität des Spaltdichtelementes 210 hängt vom Radius R des gewölbten Federabschnittes 214, vom Öffnungswinkel ϕ des gewölbten Federabschnittes 214, von der Materialstärke des Spaltdichtelementes 210 sowie von einem Hebel L ab. Der Hebel L ergibt sich dabei als der Abstand des Mittelpunktes des gewölbten Federabschnittes 214 von einer gedachten Verbindungslinie zwischen den Stützabschnitten 212, die diejenigen Punkte der Stützabschnitte 212 miteinander verbindet, an denen beim Erwärmen der Hitzeschildelemente 16 die das Hitzeschildelement komprimierende Kraftvektoren angreifen. Im dargestellten Ausführungsbeispiel ist der Radius R des gewölbten Federabschnittes 214 groß im Vergleich zum Abstand zwischen den Stützabschnitten 212. Entsprechend ist der Öffnungswinkel ϕ relativ klein. Der Hebel L beträgt ca. 1 mm.The spring elasticity of the gap sealing element 210 depends on the radius R of the arched spring section 214, on the opening angle φ of the arched spring section 214, on the material thickness of the gap sealing element 210 and on a lever L. The lever L results here as the distance of the center of the curved spring portion 214 from an imaginary connecting line between the support portions 212, which connects those points of the support portions 212 to each other, at which attack the heat shield member compressing the force vectors when heating the heat shield elements 16. In the illustrated embodiment, the radius R of the curved spring portion 214 is large compared to the distance between the support portions 212. Accordingly, the opening angle φ is relatively small. The lever L is about 1 mm.

Ein viertes Ausführungsbeispiel für das erfindungsgemäße Spaltdichtelement ist in den Figuren 7 und 8 dargestellt. Figur 7 zeigt das Spaltdichtelement 310 des vierten Ausführungsbeispiels in einer perspektivischen Darstellung, während Figur 8 das Spaltdichtelement 310 aus Figur 7 nach dem Einbau in einen keramischen Hitzeschild darstellt. Der keramische Hitzeschild entspricht dabei bis auf das Spaltdichtelement 310 im Wesentlichen dem mit Bezug auf das erste Ausführungsbeispiel beschriebenen Hitzeschild. Strukturen des Hitzeschildes, die denen mit Bezug auf Fig. 2 beschriebenen Strukturen entsprechen, sind daher mit denselben Bezugszeichen wie in Fig. 2 bezeichnet.A fourth embodiment of the inventive gap sealing element is in the FIGS. 7 and 8th shown. FIG. 7 shows the gap sealing element 310 of the fourth embodiment in a perspective view, while FIG. 8 the gap sealing element 310 FIG. 7 after installation in a ceramic heat shield represents. The ceramic heat shield in this case corresponds, with the exception of the gap-sealing element 310, essentially to the heat shield described with reference to the first exemplary embodiment. Structures of the heat shield related to those Fig. 2 are therefore denoted by the same reference numerals as in FIG Fig. 2 designated.

Das in Figur 7 dargestellte Spaltdichtelement 310 ähnelt in seiner Grundstruktur dem in Figur 5 dargestellten Spaltdichtelement 210. Wie dieses weist es zwei gebogene Stützabschnitte 312 auf, die über einen gewölbten Federabschnitt 314 miteinander verbunden sind. Im Vergleich zum gewölbten Federabschnitt 214 des Spaltdichtelementes 210 aus dem dritten Ausführungsbeispiel weist der gewölbte Federabschnitt 314 des Spaltdichtelementes 310 einen Querschnitt mit einem kleineren Krümmungsradius R, einem größeren Öffnungswinkel ϕ und einem größeren Hebel L auf. Außerdem ist der Querschnitt der Stützabschnitte 312 nicht mehr halbkreisförmig wie beim Spaltdichtelement 210 aus den Figuren 5 und 6. Stattdessen schließt sich in den Stützabschnitten 312 des Spaltdichtelementes 310 von den Kanten 315 aus gesehen an einen Abschnitt mit kreisförmigen Profil, das etwa einem Kreisausschnitt mit einem Winkel zwischen 45° und 60° entspricht, ein Abschnitt an, in dem sich der Krümmungsradius verringert, sodass die Stützabschnitte 312 im Vergleich zu den Stützabschnitten 212 einen ein zusammengedrückten Eindruck vermitteln.This in FIG. 7 shown gap sealing element 310 is similar in its basic structure in FIG. 5 Like this, it has two curved support portions 312 which are connected to each other via a curved spring portion 314. Compared to the curved spring portion 214 of the gap sealing element 210 of the third embodiment, the curved spring portion 314 of the gap sealing element 310 has a cross section with a smaller radius of curvature R, a larger opening angle φ and a larger lever L. In addition, the cross section of the support portions 312 is no longer semicircular as in the gap sealing element 210 of the Figures 5 and 6 , Instead, in the support portions 312 of the gap seal member 310, as viewed from the edges 315, to a portion having a circular profile corresponding approximately to a circular cut with an angle between 45 ° and 60 °, a portion where the radius of curvature decreases closes, so that the support portions 312 provide a compressed impression compared to the support portions 212.

Im Vergleich zum Spaltdichtelement 210 wird das Spaltdichtelement 310 in entgegengesetzter Orientierung in die Nuten 30 der keramischen Hitzeschildelemente 16 eingesetzt (vergl. Figuren 6 und 8). Während beim Spaltdichtelement 210 im eingesetzten Zustand die Wölbung des gewölbten Federabschnittes 214 in Richtung auf die Halteelemente 18 vorspringt und die Stützabschnitte 212 in Richtung auf die Halteelemente 18 umgebogen sind, wölbt sich der gewölbte Federabschnitt 314 im vierten Ausführungsbeispiel von den Halteelementen 18 weg, und die Stützabschnitte 312 des Spaltdichtelementes 310 sind im eingesetzten Zustand von den Halteelementen 18 weg gebogen. Die Stützabschnitte 312 liegen zudem nicht so großflächig an den Nutböden 31 an, wie die Stützabschnitte 212 des dritten Ausführungsbeispiels. Die Anlage beschränkt sich bei den Stützabschnitten 312 des vierten Ausführungsbeispiels im Wesentlichen auf die dem heißseitigen Abschnitt des Hitzeschildelementes zugewandten Abschnitte der Nutböden 31.Compared to the gap-sealing element 210, the gap-sealing element 310 is inserted into the slots 30 of the ceramic heat-shield elements 16 in opposite orientation (see FIG. FIGS. 6 and 8th ). While the gap sealing element 210 in the inserted state, the curvature of the curved spring portion 214 protrudes in the direction of the support members 18 and the support portions 212 are bent toward the support members 18, the curved spring portion 314 bulges in the fourth embodiment of the support members 18, and the Supporting portions 312 of the gap sealing element 310 are bent away from the holding elements 18 in the inserted state. Moreover, the support sections 312 do not lie against the groove bottoms 31 over such a large area as the support sections 212 of the third exemplary embodiment. In the support sections 312 of the fourth exemplary embodiment, the installation is essentially limited to the sections of the groove bottoms 31 facing the hot-side section of the heat shield element.

Gegenüber dem Spaltdichtelement 210 weist das Spaltdichtelement 310 eine geringere Steifigkeit auf. Außerdem werden, wenn sich die Nutböden 31 aufgrund der Wärmeausdehnung der Hitzeschildelemente 16 aufeinander zu bewegen, im Spaltdichtelement 310 weniger Spannungen erzeugt als im Spaltdichtelement 210.Compared to the gap sealing element 210, the gap sealing element 310 has a lower rigidity. In addition, when the groove bottoms 31 move toward each other due to the thermal expansion of the heat shield members 16, less stress is generated in the gap seal member 310 than in the gap seal member 210.

Ein fünftes Ausführungsbeispiel für das erfindungsgemäße Spaltdichtelement ist in den Figuren 9 und 10 dargestellt. Figur 9 zeigt das Spaltdichtelement 410 des fünften Ausführungsbeispiels in einer perspektivischen Darstellung, während Figur 10 das Spaltdichtelement 410 aus Figur 9 nach dem Einbau in einen keramischen Hitzeschild darstellt. Der keramische Hitzeschild entspricht dabei bis auf das Spaltdichtelement 410 im Wesentlichen dem mit Bezug auf das erste Ausführungsbeispiel beschriebenen Hitzeschild. Strukturen des Hitzeschildes, die denen mit Bezug auf Fig. 2 beschriebenen Strukturen entsprechen, sind daher mit denselben Bezugszeichen wie in Fig. 2 bezeichnet.A fifth embodiment of the inventive gap sealing element is in the Figures 9 and 10 shown. FIG. 9 shows the gap sealing element 410 of the fifth embodiment in a perspective view, while FIG. 10 the gap sealing element 410 FIG. 9 after installation in a ceramic heat shield represents. The ceramic heat shield corresponds to the gap sealing element 410 substantially with respect to the first embodiment described heat shield. Structures of the heat shield related to those Fig. 2 are therefore denoted by the same reference numerals as in FIG Fig. 2 designated.

Das Spaltdichtelement 410 weist wie die Spaltdichtelemente 210 und 310 des dritten bzw. des vierten Ausführungsbeispiels einen gewölbten Federabschnitt 414 sowie zwei Stützabschnitte 412 auf. Der gewölbte Federabschnitt 414 besitzt einen Krümmungsradius, der in etwa dem des vierten Ausführungsbeispiels entspricht. Der Öffnungswinkel ϕ und der Hebel L sind jedoch deutlich größer als beim vierten Ausführungsbeispiel. Die Stützabschnitte 412 sind im fünften Ausführungsbeispiel lediglich als abknickende Kanten des Spaltdichtelementes 410 ausgebildet. Sie weisen nur eine leichte Krümmung auf, die an die Kontur des Nutbodens 31 angepasst ist (siehe Figur 10).The gap-sealing element 410, like the gap-sealing elements 210 and 310 of the third and fourth embodiment, has a curved spring section 414 and two support sections 412. The curved spring portion 414 has a radius of curvature which is approximately equal to that of the fourth embodiment. However, the opening angle φ and the lever L are significantly larger than in the fourth embodiment. The support portions 412 are formed in the fifth embodiment only as kinking edges of the gap sealing element 410. They have only a slight curvature, which is adapted to the contour of the groove bottom 31 (see FIG. 10 ).

Die Materialstärke des Spaltdichtelementes 410 ist entlang der Ausdehnungsrichtung A nicht konstant, sondern weist in der Mitte des gewölbten Federabschnittes 414 mit ca. 1,2 mm die größte Materialstärke auf. In Richtung auf die Stützabschnitte 412 nimmt die Materialstärke linear ab und erreicht in der Nähe der Stützabschnitte 412 etwa einen Wert von 0,6 mm. Entlang der Ausdehnungsrichtung B ist die Materialstärke wie in den Ausführungsbeispielen drei und vier konstant.The material thickness of the gap sealing element 410 is not constant along the expansion direction A, but has the greatest material thickness in the center of the arched spring section 414 with approximately 1.2 mm. In the direction of the support portions 412, the material thickness decreases linearly and reaches in the vicinity of the support portions 412 about a value of 0.6 mm. Along the expansion direction B, the material thickness is constant as in the exemplary embodiments three and four.

Das Spaltdichtelement 410 wird mit derselben Orientierung wie das Spaltdichtelement 310 des vierten Ausführungsbeispiels in die Nuten 30 der keramischen Hitzeschildelemente 16 eines Hiteschildes eingesetzt. Im eingesetzten Zustand liegen die Stützabschnitte 412 im Wesentlichen in Richtung auf die Nutwand 35 des kaltseitigen Abschnittes der Hitzeschildelemente 16 hin verschoben am Nutboden 31 an. Der gewölbte Federabschnitt 414 überspannt dabei die Eingriffsabschnitte der Halteelemente 18 praktisch vollständig.The gap seal member 410 is inserted into the grooves 30 of the ceramic heat shield members 16 of a hit sign in the same orientation as the gap seal member 310 of the fourth embodiment. In the inserted state, the support sections 412 lie substantially in the direction of the groove wall 35 of the cold-side section of the heat shield elements 16 displaced toward the groove bottom 31. The curved spring portion 414 spans the Engagement portions of the holding elements 18 practically completely.

Die Geometrie des fünften Ausführungsbeispiels weist eine besonders gute Dichtfunktion sowie besonders günstige Steifigkeits- und Spannungseigenschaften auf. Im fünften Ausführungsbeispiel liegt der Krümmungsradius R des gewölbten Federabschnittes 414 im Bereich zwischen 30 und 40 mm, vorzugsweise bei ca. 35 mm, der Öffnungswinkel im Bereich zwischen 50° und 60°, vorzugsweise bei ca. 56°, und der Hebel im Bereich zwischen 8 und 10 mm, vorzugsweise bei ca. 9 mm. Die Materialdicke des Spaltdichtelementes 410 nimmt von ca. 1,2 mm im Zentrum des gewölbten Federabschnittes auf ca. 0,6 mm am Rand des gewölbten Federabschnittes 414 ab. Im Bereich der Stützabschnitte 412 nimmt die Materialstärke dann wieder etwas zu.The geometry of the fifth embodiment has a particularly good sealing function and particularly favorable stiffness and stress properties. In the fifth embodiment, the radius of curvature R of the arched spring portion 414 is in the range between 30 and 40 mm, preferably at about 35 mm, the opening angle in the range between 50 ° and 60 °, preferably at about 56 °, and the lever in the range between 8 and 10 mm, preferably at about 9 mm. The material thickness of the gap sealing element 410 decreases from about 1.2 mm in the center of the arched spring section to about 0.6 mm at the edge of the arched spring section 414. In the area of the support sections 412, the material thickness then increases again somewhat.

Die Strömungsverhältnisse entlang eines keramischen Hitzeschildelementes 16 bei eingebautem Spaltdichtelement sind in Figur 11 dargestellt. In Figur 11 ist ein Spaltdichtelement des fünften Ausführungsbeispiels eingebaut. Es könnten jedoch auch Spaltdichtelemente der übrigen Ausführungsbeispiele eingebaut sein. Durch jeweils vier Kühlluftöffnungen 34 in der Tragstruktur 20 im Bereich eines durch erste Umfangsflächen 26 begrenzten Dehnspaltes des keramischen Hitzeschildes wird Kühlluft an die entsprechenden Spaltdichtelemente 410 angeblasen. Die Kühlluftströme - in Figur 11 sind dies entsprechend der Anzahl der Kühlluftöffnungen 34 vier Kühlluftströme - treten aus den Kühlluftöffnungen 34 in Richtung auf das Spaltdichtelement 410 aus. Vom Spaltdichtelement 410 werden die Kühlluftströme im Wesentlichen im rechten Winkel derart abgelenkt, dass sie unterhalb des Spaltdichtelementes 410 parallel zum Spaltdichtelement 410 strömen. Sobald die Kühlluftströme einen Dehnspalt zwischen zwei einander gegenüberliegenden zweiten Umfangsflächen 28 erreichen, treten sie in diesen Dehnspalt ein und ändern ihre Strömungsrichtung erneut um ca. 90°, sodass sie nun wieder von der Tragstruktur 20 wegströmen, d.h. in Richtung auf die Gasturbinenbrennkammer. Auf diese Weise werden die Dehnspalte zwischen zwei einander gegenüberliegenden zweiten Umfangsflächen 28 durch die Kühlluft gegen das Eindringen von Heißgas aus der Gasturbinenbrennkammer abgesperrt.The flow conditions along a ceramic heat shield element 16 with built-in gap sealing element are in FIG. 11 shown. In FIG. 11 a gap sealing element of the fifth embodiment is installed. However, it could also be installed gap sealing elements of the other embodiments. By four cooling air openings 34 in the support structure 20 in the region of a limited by first peripheral surfaces 26 expansion gap of the ceramic heat shield cooling air is blown to the corresponding gap sealing elements 410. The cooling air flows - in FIG. 11 if these are four cooling air flows corresponding to the number of cooling air openings 34, they exit from the cooling air openings 34 in the direction of the gap sealing element 410. From the gap sealing element 410, the cooling air streams are deflected substantially at right angles in such a way that they flow below the gap sealing element 410 parallel to the gap sealing element 410. As soon as the cooling air flows reach an expansion gap between two opposite second peripheral surfaces 28, they enter this expansion gap and change their flow direction again by approx. 90 °, so that they now flow away from the support structure 20, ie in the direction of the gas turbine combustor. In this way, the expansion gaps between two opposite second peripheral surfaces 28 are shut off by the cooling air against the penetration of hot gas from the gas turbine combustor.

Um zu verhindern, dass die Kühlluftströme im Bereich der Dehnspalte zwischen zwei zweiten Umfangsflächen 28 statt in Richtung auf die Gasturbinenbrennkammer teilweise oder vollständig in Richtung auf die Tragstruktur 20 strömen, können an den Unterkanten der Umfangsflächen 28 sog. Kaltdichtungen 450 vorhanden sein, die einem Strömen der Kühlluftströme in Richtung der Tragstruktur 20 entgegenwirken. Zusätzlich können die zweiten Umfangsflächen 28 außerdem statt einer planaren Struktur eine konvexe Struktur besitzen, wodurch sich andere Geschwindigkeitsverteilungen der Kühlluftströmung ergeben. Mittels der Formgebung der zweiten Umfangsflächen kann dabei die Geschwindigkeitsverteilung beeinflusst und somit die Kühlwirkung optimiert werden.In order to prevent the cooling air flows in the region of the expansion gaps between two second peripheral surfaces 28 instead of towards the gas turbine combustor flow partially or completely in the direction of the support structure 20, so-called. Cold seals 450 may be present at the lower edges of the peripheral surfaces, the flow counteract the cooling air flows in the direction of the support structure 20. In addition, the second peripheral surfaces 28 may also have a convex structure instead of a planar structure, which results in different velocity distributions of the cooling air flow. By means of the shaping of the second circumferential surfaces, the velocity distribution can be influenced and thus the cooling effect can be optimized.

Es ist zu erwähnen, dass die Strömungsverhältnisse entlang der keramischen Hitzeschildelemente auch von der Form der Spaltdichtelemente sowie von der Anordnung der Austrittsöffnungen 34 für die Kühlluftströme abhängen. Zum Optimieren der Kühlluftströmung ist daher immer die Gesamtheit aus Spaltdichtelement, Anordnung der Kühlluftaustrittsöffnungen 34 und Formgebung des Hitzeschildelementes 16, insbesondere seiner zweiten Umfangsflächen 28, zu berücksichtigen. Beispielsweise können bei der Optimierung gute Ergebnisse erzielt werden, wenn Spaltdichtelemente 410 gemäß dem fünften Ausführungsbeispiel Verwendung finden und die Tragstruktur 20 im Bereich zwischen den Elementhaltern 18 sechs Kühlluftöffnungen 34 enthält, die sich linear zwischen den Elementhaltern 18 erstrecken, eine Austrittsöffnung von ca. 2,25 mm aufweisen und ca. 3,8 mm voneinander beabstandet sind. Dabei wird angenommen, dass die keramischen Hitzeschildelemente eine quadratische Struktur mit einer Kantenlänge von 200 mm und einer Dicke von 38 mm aufweisen.It should be mentioned that the flow conditions along the ceramic heat shield elements also depend on the shape of the gap sealing elements and on the arrangement of the outlet openings 34 for the cooling air flows. For optimizing the cooling air flow, therefore, the entirety of the gap sealing element, the arrangement of the cooling air outlet openings 34 and the shaping of the heat shield element 16, in particular its second peripheral surfaces 28, must always be taken into account. For example, good results can be achieved in the optimization, if gap sealing elements 410 according to the fifth embodiment are used and the support structure 20 contains in the area between the element holders 18 six cooling air openings 34 which extend linearly between the element holders 18, an outlet opening of about 2, 25 mm and about 3.8 mm spaced apart from each other. It is assumed that the ceramic heat shield elements have a square structure with an edge length of 200 mm and a thickness of 38 mm.

Claims (15)

  1. Gap sealing element for sealing gaps between adjacent heat shield elements (16) of a heat shield, wherein the gap sealing element (10; 110; 210; 310; 410) comprises at least one elastic section (14; 114; 214; 314; 414) which is designed for exerting a spring force in such a way that the gap sealing element (10; 110; 210; 310; 410) inserted into a gap between adjacent heat shield elements (16) is held in the gap by means of a force fit, wherein the at least one elastic section (214; 314; 414) has an arch which projects perpendicularly to the direction of action of the spring force for producing the force fit, characterized in that the material thickness in the region of the arch is greater than in the other regions of the gap sealing element.
  2. Gap sealing element according to Claim 1, characterized in that it is designed for sealing gaps between opposite circumferential surfaces (26), each having a groove (30), of adjacent heat shield elements (16) in such a way that, in a manner sealing the gap, it can be inserted into the grooves (30) of the circumferential surfaces (26) of heat shield elements (16) adjacent to one another in such a way that one part of it is arranged in the groove of the one circumferential surface (26) and another part is arranged in the groove (30) of the opposite circumferential surface (26).
  3. Gap sealing element according to Claim 1 or 2, characterized in that the at least one elastic section (14; 114) has an arch which projects in the direction of the spring force for producing the force fit.
  4. Gap sealing element according to Claim 2, characterized in that it comprises two opposite supporting sections (212; 312; 412) for supporting on the groove bases (31) of the grooves (30), and the at least one elastic section (214; 314; 414) connects the supporting sections (212; 312; 412) to one another.
  5. Gap sealing element according to Claim 4, characterized in that the arch has a profile corresponding approximately to a circle sector having an opening angle ϕ and an arch radius R and has an arch lever L.
  6. Gap sealing element according to Claim 5, characterized in that the opening angle ϕ has a value within the range of 50° to 60°, the radius R has a value within the range of 30 to 40 mm and the arch lever L has a value within the range of 8 to 10 mm.
  7. Heat shield on a supporting structure (20) for protecting the supporting structure (20) and/or a wall surrounding the supporting structure (20) or connected to the supporting structure (20) against a hot gas, comprising a number of heat shield elements (16) which are adjacent to one another while leaving a gap, characterized in that gap sealing elements (10; 110; 210; 310; 410) according to one of Claims 1 to 6 are arranged in the gaps.
  8. Heat shield according to Claim 7, characterized in that the heat shield elements (16) have circumferential surfaces (26) defining the gaps and provided with grooves (30), and in that gap sealing elements (10; 110; 210; 310; 410) according to Claim 2 or according to Claim 2 and one of Claims 3 to 6 are arranged in the grooves (30) of opposite circumferential surfaces (26) and are held by means of a force fit.
  9. Heat shield according to Claim 8, characterized in that the at least one elastic section (14; 114) of the gap sealing elements (10; 110) is configured in such a way that the spring force producing the force fit acts between the supporting structure (20) and groove walls (33) of grooves (30) of circumferential surfaces (26) defining a gap.
  10. Heat shield according to Claim 8, characterized in that the at least one elastic section (114) of the gap sealing elements (110) is configured in such a way that the spring force producing the force fit acts between two opposite groove sections (35, 33) of the grooves (30) of circumferential surfaces (26) defining a gap.
  11. Heat shield according to Claim 10, characterized in that the at least one elastic section (114) is configured in such a way that the spring force producing the force fit acts between two opposite groove walls (35, 33) of the same groove (30).
  12. Heat shield according to Claim 8, characterized in that the at least one elastic section (214; 314; 414) is configured in such a way that the spring force producing the force fit acts between the groove bases (31) of the grooves (30) of circumferential surfaces (26) defining a gap.
  13. Heat shield according to one of Claims 7 to 12, characterized in that there are cooling air openings (34) in the supporting structure (20) for feeding cooling air in the direction of the gap sealing elements (10; 110; 210; 310; 410).
  14. Heat shield according to one of Claims 7 to 13, characterized in that the heat shield elements (16) are ceramic heat shield elements.
  15. Heat shield according to one of Claims 7 to 14, and comprising a gap sealing element according to Claim 2 and Claim 3, characterized in that it has dimensions which are selected in such a way that it does not extend up to the bases (31) of the grooves (30) of the circumferential surfaces (26) in the hottest state of the heat shield elements (16).
EP04010306A 2004-04-30 2004-04-30 Gap sealing element for a heat shield Not-in-force EP1591724B1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AT04010306T ATE514905T1 (en) 2004-04-30 2004-04-30 GAP SEALING ELEMENT FOR A HEAT SHIELD
EP04010306A EP1591724B1 (en) 2004-04-30 2004-04-30 Gap sealing element for a heat shield

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP04010306A EP1591724B1 (en) 2004-04-30 2004-04-30 Gap sealing element for a heat shield

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EP1591724A1 EP1591724A1 (en) 2005-11-02
EP1591724B1 true EP1591724B1 (en) 2011-06-29

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US8359865B2 (en) * 2010-02-04 2013-01-29 United Technologies Corporation Combustor liner segment seal member
CN105339738B (en) * 2013-06-27 2017-07-04 西门子股份公司 Fasten heat shield block to supporting construction, and heat shield
US9988923B2 (en) 2013-08-29 2018-06-05 United Technologies Corporation Seal for gas turbine engine
DE102015202570A1 (en) * 2015-02-12 2016-08-18 Rolls-Royce Deutschland Ltd & Co Kg Sealing of a marginal gap between effusion shingles of a gas turbine combustor
US10101029B2 (en) * 2015-03-30 2018-10-16 United Technologies Corporation Combustor panels and configurations for a gas turbine engine
US11408609B2 (en) * 2018-10-26 2022-08-09 Collins Engine Nozzles, Inc. Combustor dome tiles
DE102019204746A1 (en) * 2019-04-03 2020-10-08 Siemens Aktiengesellschaft Heat shield tile with damping function
EP3845810B1 (en) * 2019-12-31 2023-11-22 ANSALDO ENERGIA S.p.A. Supporting device for a heat-insulating tiles of a combustion chamber of a gas turbine assembly for power plants and a gas turbine assembly

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EP1022437A1 (en) 1999-01-19 2000-07-26 Siemens Aktiengesellschaft Construction element for use in a thermal machine
US6702549B2 (en) * 2000-03-02 2004-03-09 Siemens Aktiengesellschaft Turbine installation
EP1191285A1 (en) * 2000-09-22 2002-03-27 Siemens Aktiengesellschaft Heat shield panel, combustion chamber with inner lining and a gas turbine
EP1260767A1 (en) 2001-05-25 2002-11-27 Siemens Aktiengesellschaft Heat shield assembly for a high temperature gas conveying component, in particular for structural components of gas turbines, as well as process for producing such an assembly
EP1302723A1 (en) 2001-10-15 2003-04-16 Siemens Aktiengesellschaft Lining for combustion chamber inside walls

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DE102019200593A1 (en) * 2019-01-17 2020-07-23 Siemens Aktiengesellschaft Combustion chamber

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ATE514905T1 (en) 2011-07-15

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