EP4078031B1 - Combustion chamber with heat shield tiles - Google Patents

Description

The invention relates to a heat shield tile for use in a combustion chamber, in particular of a gas turbine, wherein the heat shield tile is fixed in a transverse direction by the fastening means and can be secured in a longitudinal direction by a fixing element.

Heat shield tiles are well known from the state of the art. There are solutions in which the heat shield tile is attached to a support with screws and is thus essentially fixed in the plane of the heat shield tile. Examples of this are from the EP1884317B1 , EP2992270B1 and WO 2018137803 A1 known. In contrast, designs of heat shield tiles are also used which are attached using elastic stone holders. It is usual for the stone holders to be arranged on two opposite side edges and thus essentially prevent movement in the transverse direction. Designs of this are known, for example, from EP1701095B1 known.

In the usual application of heat shield tiles, they are attached to a support structure in several rows all around the combustion chamber. To avoid contact between adjacent heat shield tiles, there is usually a small gap between the respective heat shield tiles.

It is known to be problematic when individual heat shield tiles shift, particularly due to vibrations occurring during operation, and the gap between some heat shield tiles becomes smaller and between other heat shield tiles larger, although this problem does not usually occur. In the case of clamped heat shield tiles, a shift in a transverse direction along the row is prevented by the stone holders.

The displacement of the heat shield tiles in the longitudinal direction, ie from row to row, is also undesirable, since an uneven distribution of gaps leads to an increased air consumption for blocking the gaps against the ingress of hot exhaust gases. Displacement is also possible when using specially shaped heat shield tiles (see for example the design from the EP3017253B1 ) is a disadvantage.

For this purpose, the state of the art in the EP3134680B1 A combustion chamber with corresponding heat shield tiles is known in which skid-like elevations are arranged on the side of the heat shield tile facing the supporting structure, which engage in fastening grooves of the supporting structure and thus prevent displacement in the longitudinal direction.

Although the previous designs for fixing in the longitudinal direction have proven to be successful, there is a requirement, among other things, to simplify the production of the heat shield tile and to reduce the dimensions relevant for storage and transport by means of an advantageous geometry in this regard.

In the EP1715248A1 An alternative possibility for the axial fixation of a heat shield tile in a combustion chamber of a gas turbine is disclosed. This is arranged on a support structure on the side facing the combustion chamber and is fixed with stone holders to grooves running in the longitudinal direction. For axial fixation, the heat shield tiles each have a recess on the side edge at the position of the stone holders, into which a shoulder attached to the stone holders engages.

The object of the present invention is therefore to enable, based on the known solutions for axial fixation, both an advantageous production and storage of the heat shield tiles and to ensure the required service life, whereby the axial positioning must be achieved as precisely as possible.

The stated object is achieved by an inventive embodiment of a combustion chamber according to the teaching of claim 1.

Advantageous embodiments are the subject of the subclaims.

The generic combustion chamber has a supporting structure on which heat shield elements are attached in several rows. The type of combustion chamber is initially irrelevant. However, its use is particularly advantageous in the combustion chamber of a gas turbine.

The heat shield elements are made of a ceramic material. This has a hot side that faces the combustion chamber when used in the combustion chamber and an opposite cold side that faces a supporting structure of the combustion chamber. The heat shield elements extend in a longitudinal direction and perpendicular to this in a transverse direction. The hot side is connected to the cold side via two longitudinal edges running along the longitudinal direction and two transverse edges running along the transverse direction. Each longitudinal edge has at least one fastening receptacle to which a fastening means for fastening the heat shield tile can be attached when the heat shield elements are installed in the combustion chamber. can be attached. The design of the longitudinal and transverse edges is otherwise initially irrelevant.

To enable the heat shield elements to be attached to the supporting structure, the supporting structure must have several fastening grooves that are spaced apart from one another in the longitudinal direction and run transversely around the entire structure. The necessary fastening devices can be attached to these fastening grooves.

According to the invention, it is now provided that at least one row of the heat shield elements is formed by heat shield tiles which can be fixed in the longitudinal direction.

To enable the heat shield tile to be fixed in the longitudinal direction while reducing the construction volume, the invention provides that the heat shield tile has at least one fixing recess on the cold side. This inevitably means that the fixing recess does not penetrate the heat shield tile, but rather its surface on the hot side remains unchanged (despite the fixing recess now present on the cold side).

For this purpose, the support structure has at least one fixing elevation that engages in the respective fixing recess of the respective heat shield tile. It can be provided that the fixing elevation is mounted or firmly connected to the support structure.

On the one hand, in order to allow a certain displacement in the transverse direction even when a means engages in the fixing recess (or in order to be able to bring the heat shield tile into the exact desired position) and on the other hand to avoid damage or abrasion when a means is placed on a flank of the fixing recess, the invention further provides that the fixing recess extends in the transverse direction over at least 0.1 times the width of the heat shield tile. With this length, In this regard, this refers to the section of the fixing recess which enables the heat shield tile to be secured in the longitudinal direction.

By creating the fixing recess in the heat shield tile, fixing in the longitudinal direction is possible without the construction volume being larger than that of a heat shield tile without the possibility of fixing in the longitudinal direction. This simplifies production and storage.

With regard to the fixation in the longitudinal direction, it may initially be sufficient if this is only provided in one direction. For example, if the known fixation from the prior art is omitted, only a downstream displacement of the heat shield tile is to be expected, then blocking against downstream displacement is sufficient.

In contrast, it can be particularly advantageous if the fixing recess enables the heat shield tile to be blocked longitudinally in both opposite directions.

It is particularly advantageous if the depth of the fixing recess, viewed in one direction from the cold side to the hot side, corresponds to at least 0.1 times the thickness of the heat shield tile, i.e. the distance from the cold side to the hot side. It is particularly advantageous if the fixing recess has a depth of at least 0.15 times the thickness of the heat shield tile. In contrast, it is advantageous if the depth of the fixing recess is not greater than 0.3 times the thickness of the heat shield tile. A depth of at most 0.15 times the thickness of the heat shield tile is particularly advantageous here.

There are various possibilities for realizing the fixing recess, whereby in a first advantageous embodiment the fixing recess is in transverse direction and has a length in the transverse direction of at least 0.5 times the width of the heat shield tile in the transverse direction. It is particularly advantageous if the fixing recess extends over the entire width of the heat shield tile from one longitudinal edge to the opposite longitudinal edge.

The continuous fixing recess facilitates advantageous production on the one hand and on the other hand various options for fixing in the combustion chamber are created by means of the fixing recess. In particular, with a suitable design of the combustion chamber, a displacement in the transverse direction, for example for assembly, is possible when there is fixing in the longitudinal direction.

In contrast, in a second embodiment it is advantageously provided that at least two fixing recesses are present which are offset from one another in the transverse direction. In this case it is also advantageous if the fixing recess extends over a maximum of 0.3 times the width of the heat shield tile.

By using at least two pocket-shaped fixing recesses, the heat shield tile is not weakened unnecessarily, so that both its insulating function is largely guaranteed and its stability is largely maintained.

Due to the generally high load on the heat shield tiles at their edges due to the gaps between the heat shield tiles, it is advantageous if the fixing recess is at least spaced from the transverse edges.

In an advantageous variant, it is possible to arrange the fixing recess approximately - viewed in the longitudinal direction - in the middle of the heat shield tile. This is considered to be the case if it is in the middle of the Heat shield tile or the distance from the centre of the fixing recess to the centre of the heat shield tile in the longitudinal direction corresponds to a maximum of 0.2 times the length of the heat shield tile in the longitudinal direction.

In a second advantageous variant, the fixing recess is arranged at the level of the fastening means arranged opposite one another as intended. If the heat shield tile has a special shape for attaching the fastening means, the position in the longitudinal direction is directly determined.

It is also particularly advantageous if the heat shield tile has two fastening receptacles on each longitudinal edge that are spaced apart from one another in the longitudinal direction. The fastening receptacles are designed in such a way that the attachment of the respective fastening means is provided approximately in the middle of the respective fastening receptacle in the longitudinal direction. In this case, the at least one fixing recess, particularly advantageously the two fixing recesses that are spaced apart from one another, is located between two opposing fastening receptacles.

Otherwise, the advantageous position of the fixing recess between two fastening means results from the intended use of the heat shield tile. In particular, in this case the position of the fastening means to be attached in the longitudinal direction can be fixed to the position of the fixing recess.

The newly created heat shield tile enables the realization of a new type of combustion chamber according to the invention. This is particularly advantageous when it is the combustion chamber of a gas turbine. In principle, it is not intended that all heat shield tiles of the combustion chamber are provided with a fixing recess. Rather, in a particularly advantageous manner at least one circumferential row (for example two or three rows) is provided with heat shield tiles with a fixing recess, for which a fixing elevation on the supporting structure is then required. In contrast, further rows of heat shield tiles can be provided which do not have a fixing recess or for which there is no fixing elevation.

How the fixing elevation is designed is initially irrelevant. It can be provided that there is a fixing elevation for each fixing recess, but it is also possible to provide a fixing elevation for two or more fixing recesses.

The realization of at least one fixing elevation on the supporting structure enables the use of the heat shield tile according to the invention, so that its advantageous production and storage can be utilized.

This results in two particularly advantageous embodiments for the implementation of the fixing elevation. In a first advantageous design, the support structure for a circumferential row of heat shield tiles has a circumferential fixing elevation. It is obvious that in this case the fixing recess must extend across the entire width in the transverse direction. This allows the heat shield tile to be easily installed and does not make the production of the support structure unnecessarily difficult.

In contrast, in a second advantageous embodiment, the support structure has several fixing elevations spaced apart from one another in the circumferential direction. This advantageously enables the use of heat shield tiles both with a continuous fixing recess and the use of heat shield tiles with a fixing recess that does not extend continuously in the transverse direction.

It is particularly advantageous if two fixing elevations are present for each of the heat shield tiles that have a continuous fixing recess or at least two fixing recesses. These are spaced apart from one another in the transverse direction. It is advantageous if the two fixing elevations belonging to a heat shield tile with a fixing recess are arranged at the same height in the longitudinal direction.

If the fixing elevation is not formed by a circumferential web in the first variant, the second variant provides for the fixing elevations to be formed by mounted centering elements. This simplifies the manufacture of the support structure with fixing elevations in the circumferential direction. In particular, this embodiment enables retrofitting to existing systems.

It is also particularly advantageous if the fixing elevations are fastened in at least one circumferential fastening groove of the support structure. This enables a simple, uncomplicated realization of the combustion chamber according to the invention.

Fig. 1

ein erstes Ausführungsbeispiel einer Hitzeschildkachel mit einer durchgehenden Fixierausnehmung;

Fig. 2

ein zweites Ausführungsbeispiel einer Hitzeschildkachel mit zwei beanstandeten Fixierausnehmungen;

Fig. 3

ein Schnitt durch eine Brennkammer im Bereich der Hitzeschildkachel gemäß Fig. 1;

Fig. 4

ein Schnitt durch eine Brennkammer im Bereich der Hitzeschildkachel gemäß Fig. 2;

Fig. 5

ein drittes Ausführungsbeispiel einer Hitzeschildkachel mit zwei beanstandeten Fixierausnehmungen;

Fig. 6

ein Schnitt durch eine Brennkammer im Bereich der Hitzeschildkachel gemäß Fig. 5;

Fig. 7

die Vorderseite der Hitzeschildkachel;

Fig. 8

eine beispielhafte Ausführung eines Befestigungsmittels mit einer Fixiererhebung.

The following figures outline two exemplary embodiments of a heat shield tile according to the invention. They show:

Fig.1

a first embodiment of a heat shield tile with a continuous fixing recess;

Fig.2

a second embodiment of a heat shield tile with two objectionable fixing recesses;

Fig.3

a section through a combustion chamber in the area of the heat shield tile according to Fig.1 ;

Fig.4

a section through a combustion chamber in the area of the heat shield tile according to Fig.2 ;

Fig.5

a third embodiment of a heat shield tile with two objectionable fixing recesses;

Fig.6

a section through a combustion chamber in the area of the heat shield tile according to Fig.5 ;

Fig.7

the front of the heat shield tile;

Fig.8

an exemplary design of a fastening device with a fixing elevation.

In the Figure 1 a first embodiment of a heat shield tile 01 according to the invention is sketched in a perspective view. This 01 is shown from a cold side 03. The flat shape can be seen with the cold side 03 visible in this view, with the hot side 02 located opposite (on the hidden underside). When the heat shield tile 01 is used as intended, the cold side 03 faces a support structure 21 of a combustion chamber, with the hot side 02 arranged facing a combustion chamber. The hot side 02 is connected to the cold side 03 via two longitudinal edges 04 which run along a longitudinal direction. On the longitudinal edges 04 there are two fastening receptacles 06 opposite each other for attaching a fastening means 25, the so-called stone holders. Furthermore, the hot side 02 is connected to the cold side 03 via two transverse edges 05 which extend along a transverse direction.

A displacement of the heat shield tile 01 in the combustion chamber in the transverse direction in the installed state is prevented by the fastening means 25.

To prevent displacement in the longitudinal direction, the invention provides that a fixing recess 07 extending in the direction of the hot side 02 is located on the cold side 03. In this exemplary embodiment, the fixing recess 07 extends over the entire width of the heat shield tile 01 from one longitudinal edge 04 to the opposite longitudinal edge 04. Furthermore, the advantageous position of the continuous fixing recess 07 in the middle of the heat shield tile 01 (viewed in the longitudinal direction) can be seen.

In the Figure 2 a second embodiment of a heat shield tile 11 according to the invention is outlined. This is shown in perspective, similar to the previous example, with a view of the cold side 03. The hot side 02 is located opposite (also on the underside, not visible). The heat shield tile 11 again has two opposite longitudinal edges 14 extending along the longitudinal direction and two transverse edges 05 extending along a transverse direction. In contrast to the previous example, here continuous fastening receptacles 16 are used on the longitudinal edges 14. Although these 16 enable fastening means 25 to be attached in different positions, it is also provided, as before, that four fastening means 25 are used in the same position as before. This is easily apparent from the fact that there are recesses on the longitudinal edge 14 on the cold side 03 to improve the cooling of the fastening means 25.

In contrast to the previous embodiment, it is now provided that fixing recesses 17 are used on the cold side 032, which are spaced apart from one another in the transverse direction. These 17 are hereby arranged between two fastening means 25 which are to be attached as intended (relative to the Part which engages in the fastening receptacles 16).

The fixation in the longitudinal direction in the combustion chamber shows the Figure 3 with the section-by-section representation of a support structure 21 in a longitudinal section with the heat shield tile 01 attached to it. The heat shield tile 01 can be seen with a view of a longitudinal edge 14 in which the two fastening receptacles 06 are located. Accordingly, the transverse edges 05 in this representation are located at the upper and lower ends of the heat shield tile 01. The hot side 02 facing the combustion chamber is on the right-hand side in the representation and the opposite cold side 03 is on the side facing the support structure 21. Also visible is the fixing recess 07, into which a fixed elevation 23 of the support structure 21 now engages. This prevents displacement in the longitudinal direction.

Also visible are two fastening grooves 22 which are spaced apart from one another in the longitudinal direction. Fastening means 25, the so-called stone holders, are accommodated in these 22, which engage with the other end in the fastening receptacles 06 and thus fix the heat shield tile 01 to the supporting structure 21.

In the Figure 4 In the same way as before, the fastening of the heat shield tile 11 to the associated support structure 31 is sketched in a longitudinal section. The heat shield tile 11 can be seen again with the hot side 02 on the right and the cold side 03 opposite, as well as the transverse edges 05 at the top and bottom. The support structure 31 is essentially designed in the same way as before and also has the fastening grooves 22 that are spaced apart from one another. However, in contrast to the previous example, the integral fixing elevation is omitted here. Rather, in this embodiment, it is provided that the support structure 31 mounted centering elements 33. These 33 are each fastened in a fastening groove 22. Accordingly, the heat shield tile 11 has the fixing recesses 17 located between the fastening means 25, into which the centering element 33 engages as a fixing elevation.

In the Fig.5 is analogous to the Figures 1 and 3 another embodiment of a heat shield tile 41 according to the invention is outlined. As in the previous example, this 41 has a hot side 02 (concealed underside in the figure) and an opposite cold side 03 (top side in the illustration). The fastening receptacles 16 for attaching a fastening means 55 extend along the longitudinal direction on the two opposite longitudinal edges 14.

In contrast to the previous embodiment, in this example the longitudinal fixation is only effective in one direction. Accordingly, the heat shield tile 41 has two fixing recesses 47, which have a vertical flank on one side to enable the installation of a fixing elevation 53 and a bevel on the opposite side.

For this purpose, the Fig.6 analogous to the Fig.4 the heat shield tile 41 from Fig.5 sketched in longitudinal section when attached to the support structure 31. The support structure 31 with the fastening grooves 22 can be seen accordingly. While the stone holder 25 from the previous example is used in the lower fastening groove 22, it is intended that a different stone holder 55 with an integrated stop plate as a fixing elevation 53 is used in the upper fastening groove 22. As can be seen, the fixing elevation 53 in the form of the stop plate is supported on one flank of the fastening groove 22 and opposite on the flank of the fixing recess 47. This enables axial fixing in one direction in a particularly simple manner.

A particularly advantageous feature of this solution is that no additional fastening of a fixing elevation is necessary, but rather the fastening of the fixing elevation 53 in the form of the stop plate is achieved by the engagement of the longitudinally wider tabs of the fastening element 55 in the T-shaped fastening groove 22.

In the Figure 7 the heat shield tile 11 of the second embodiment is sketched again in perspective view with a view of the hot side 02. The longitudinal edges 14 with the fastening receptacles 16 and the transverse edges 05 can also be seen. According to the illustration, the cold side 03 is located on the hidden underside.

Finally, an exemplary embodiment of a fastening element 55 with an integrated fixing elevation 53, so to speak as a combination of a stone holder with a stop plate, for use in a solution according to the Figures 5 and 6 outlined.

Claims (9)

1. Combustion chamber having a rotationally symmetrical load-bearing structure (21,31), which (21,31) has multiple peripheral fastening grooves (22) spaced apart in a longitudinal direction and serving for attachment of fastening means (25), and having a plurality of heat-shield elements, which are arranged on the load-bearing structure (21,31) so as to run around peripherally in rows and which surround a combustion chamber and which are produced from a ceramic material and which have a hot side (02), which (02) is arranged oriented towards the combustion chamber, and have an oppositely situated cold side (03), which (03) is arranged oriented towards the load-bearing structure (21,31), and have a longitudinal direction and a transverse direction, wherein the hot side (02) is connected to the cold side (03) via two oppositely situated longitudinal edges (04,14), which extend along the longitudinal direction, and via two transverse edges (05), which extend along the transverse direction, wherein the longitudinal edges (04,14) each have at least one fastening receptacle (06,16), wherein the heat-shield elements are fastened to the load-bearing structure by means of fastening means (25), wherein at least one peripheral row of heat-shield tiles (01,11) is formed, wherein at least one fixing recess (07,17), which (07,17) allows the heat-shield tile (01,11) to be fixed in the longitudinal direction, is arranged on the cold side (03),

   wherein the load-bearing structure (21,31) directly or indirectly has at least one fixing elevation (23,33) which engages into a fixing recess (07,17), wherein the load-bearing structure (21) has at least one peripheral fixing elevation (23) which is arranged between two fastening grooves (22); or

   wherein the load-bearing structure (31) has multiple fixing elevations (33) which are spaced apart from one another in the transverse direction and which are formed by mounted centring elements, characterized in that the fixing recess (07) extends in the transverse direction over at least 0.1 times the width of the heat-shield tile (11).
2. Combustion chamber according to Claim 1,
   wherein the depth of the fixing recess (07,17) corresponds to at least 0.1 times, in particular to at least 0.15 times, the thickness of the heat-shield tile (01,11); and/or wherein the depth of the fixing recess (07,17) corresponds to at most 0.3 times, in particular to at most 0.25 times, the thickness of the heat-shield tile (01,11).
3. Combustion chamber according to Claim 1 or 2,
   wherein a fixing recess (07) extends in the transverse direction over at least 0.5 times the width, in particular continuously over the width, of the heat-shield tile (01).
4. Combustion chamber according to Claim 1 or 2,
   wherein provision is made of at least two fixing recesses (17) spaced apart from one another in the transverse direction, each of which (17) extends in the transverse direction over at most 0.3 times the width of the heat-shield tile (11).
5. Combustion chamber according to one of Claims 1 to 4,
   wherein the fixing recess (07,17) is spaced apart from the transverse edges (05).
6. Combustion chamber according to one of Claims 1 to 4,
   wherein the fixing recess (07) is arranged, in the longitudinal direction, in the middle of the heat-shield tile (01) or at a distance therefrom of at most 0.2 times the length of said heat-shield tile.
7. Combustion chamber according to one of Claims 1 to 4,

   wherein the fixing recess (17) is arranged, in the longitudinal direction, at the height of the attachment as intended of fastening means (25); and/or

   wherein the heat-shield tile has at each longitudinal edge two fastening receptacles spaced apart in the longitudinal direction from one another, wherein the fixing recess is arranged between two oppositely situated fastening receptacles.
8. Combustion chamber according to one of Claims 1 to 7,
   wherein the load-bearing structure (31) has in each case two mutually space apart fixing elevations (33) for each heat-shield tile (01,11) with fixing recess (07,17).
9. Combustion chamber according to one of Claims 1 to 8,
   wherein the fixing elevations (33) are fastened in at least one fastening groove (22).

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