EP2699848B1 - Combustion chamber housing and gas turbine equipped therewith - Google Patents

Description

The invention relates to a combustion chamber housing according to the preamble of claim 1 and a gas turbine equipped with such a combustion chamber housing.

A combustion chamber housing according to the preamble of claim 1 is for example made DE 10 2004 016 462 A1 known.

A combustion chamber housing and a gas turbine of the type mentioned above are also made, for example DE 10 2006 042 124 A1 known. The combustion chamber housing described there is part of a combustion chamber of the gas turbine and has a flame tube and a sheathing tube or impact grille which surrounds the flame tube and which has in its wall a plurality of passage openings, via the outside of the sheath tube aufströmende compressed air radially into between the sheath tube and the flame tube formed space can penetrate.

Combustion chambers are designed as individual modules or as annularly arranged individual burners or as annular combustion chambers. Except for the annular combustion chambers, these types always have an internal, cylindrical flame tube.

In a gas turbine as mentioned above, the combustion air is first sucked in atmospherically and then compressed in a compressor of a gas generator. The compressor may be radial or axial. In the downstream following combustion chamber, the combustion air is then greatly deflected in order to achieve an inflow into the combustion zone. In other words, the combustion air is first of the combustion chamber radially in between the casing tube and flame tube supplied space formed and then deflected so that an axial inflow of the burner take place.

In the interspace, there is a circumferential or rotating flow around the usually circular cylindrical flame tube, resulting in the pressure distribution or flow distribution of the combustion air stagnation points and trailing dents. If, in such an inhomogeneous mass flow distribution, the flow is now additionally strongly deflected as described, this inhomogeneity remains restrained. As a result, downstream components are cooled unevenly and it comes in the combustion zone to instabilities, because the air content fluctuates.

The invention has for its object to provide a combustor housing according to the preamble of claim 1 and a gas turbine equipped therewith, in which a more uniform distribution of the incoming air is ensured around the flame tube, with improved behavior with respect to different thermal expansion of the components involved.

This is achieved with a combustion chamber housing according to claim 1 or with a gas turbine according to claim 10. Further developments of the invention are defined in the dependent claims.

According to a first aspect of the invention, a combustion chamber housing is provided, in particular for a gas turbine, which has a preferably circular-cylindrical flame tube and a preferably circular-cylindrical sheathing tube or impact grille which receives and surrounds the flame tube and which has a plurality of passage openings in its wall via which outside on the sheath tube upflowing compressed air (cooling and combustion air) can penetrate radially into a preferably circular cylindrical space formed between the sheath tube and the flame tube. The invention Combustor housing is characterized by a plurality of circumferentially spaced in the space between the two tubes (flame tube and Ummantefungsrohr) arranged guide ribs, each extending radially between Ummantetungsrohr and flame tube and parallel to and along a longitudinal direction of the sheath tube and flame tube, so that the gap through the guide ribs are subdivided into a plurality of longitudinal channels preferably extending in each case over substantially the entire length of the sheathing tube and provided with through-openings, preferably having a cross-section in each case in the shape of an annular sector.

The transverse to the flow direction of the air flowing in the operating case guide ribs cause the flow around the flame tube is interrupted or prevented. This allows the air flow to distribute more evenly and the cooling of the flame tube is less disturbed. In addition, the cooling and combustion air is channel-shaped after the deflection from radial to axial flow, so that the inflow to a subsequent combustion zone can be made homogeneous.

As a result of the optimized inflow of the air, a particularly homogeneous fuel-air mixture can be formed in a combustion chamber of a gas turbine formed with the combustion chamber housing according to the invention, whereby the flame remains stable in the center of the combustion chamber during the combustion process. An imbalance or fluctuation of the flame would cause a local temperature increase of the surrounding components and thus a possible overuse, which is prevented by the guide ribs.

As a result, with the use of the inventively designed combustion chamber housing in a combustion chamber of a gas turbine unevenness of the air supply is minimized, so that operation of the combustion chamber with maximum design temperature can be carried out without restriction.

According to the invention, the guide ribs are attached to the sheath tube. In addition, each guide rib preferably extends radially so that a gap is formed between the guide rib and the flame tube.

The gap is advantageous to avoid possible distortion or stress due to different material and thermal expansion properties. Cross-flows occurring through the gaps can be neglected, as the flow always rests radially outward on the side (inner circumference of the sheathing tube) to which the flow-guiding ribs are also attached.

According to the invention, the guide ribs are each preferably strip-shaped, their respective width extending radially and their respective length extending axially or in the longitudinal direction of the casing tube and the flame tube. The thickness dimension of the respective guide ribs is preferably about 3 mm.

According to the invention, the guide rib and the passage openings formed in the wall of the jacket tube are preferably arranged such that the guide ribs do not close any of the passage openings. This advantageously ensures optimum or unhindered radial inflow of the air into the intermediate space.

According to a preferred embodiment of the invention, the number of guide ribs provided in the intermediate space is exactly eight, wherein all the guide ribs are identical to one another.

Preferably, according to the invention, the guide ribs are arranged at different circumferential angular distances from one another in the intermediate space. Of the Angular spacing preferably varies in a range of about 28 degrees to about 126 degrees.

Preferably, according to the invention, the guide ribs comprise a first group of guide ribs and a second group of guide ribs, wherein the first group of guide ribs are arranged in a predetermined first arrangement pattern with respect to their mutual circumferential angular separation, and wherein the second group of guide ribs are mutually circumferential Angular distance are arranged in a second arrangement pattern, which represents a reflection of the first arrangement pattern on an axis of symmetry of the flame tube. The symmetry axis preferably extends in cross section through the center of the flame tube.

According to a second aspect of the invention, a gas turbine having a combustion chamber housing according to one, several or all of the previously described preferred embodiments of the invention is provided in any conceivable combination.

The invention expressly extends to such embodiments, which are not given by combinations of features of explicit back references of the claims, whereby the disclosed features of the invention - as far as is technically feasible - can be combined with each other.

Fig.1

zeigt eine perspektivische teilweise gebrochene Ansicht eines Brennkammergehäuses einer Brennkammer einer Gasturbine gemäß einer Ausführungsform der Erfindung.

Fig.2

zeigt eine Stirnansicht des Brennkammergehäuses von Fig.1, jedoch ohne Flammrohr.

Fig.3

zeigt eine Schnittansicht des Brennkammergehäuses von Fig.1, gesehen entlang einer Linie A-A in Fig.2.

Fig.4

zeigt in zwei Querschnittsansichten einen Vergleich der Luftströmungs- und Druckverteilungen in dem Brennkammergehäuse von Fig.1 mit und ohne Leitrippen.

In the following the invention will be described in more detail by means of a preferred embodiment and with reference to the attached figures.

Fig.1

shows a perspective partially broken view of a combustion chamber housing a combustion chamber of a gas turbine according to an embodiment of the invention.

Fig.2

shows an end view of the combustion chamber of Fig.1 , but without flame tube.

Figure 3

shows a sectional view of the combustion chamber of Fig.1 , seen along a line AA in Fig.2 ,

Figure 4

shows in two cross-sectional views a comparison of the air flow and pressure distributions in the combustion chamber of Fig.1 with and without guide ribs.

Now, referring to the FIGS. 1 to 4 a gas turbine 1 (not fully shown) with a combustion chamber housing 10 according to an embodiment of the invention described.

The combustion chamber housing 10 of the gas turbine 1 has a circular cylindrical flame tube 20 and a circular cylindrical sheath or baffle 30, which receives and surrounds the flame tube 20 and which has in its wall a plurality of evenly distributed around the handling through openings 31, on the outer circumference the jacket tube 30 flowing through a compressor (not shown) of the gas turbine 1 compressed air (cooling and combustion air) can penetrate radially into a circular cylindrical space 40 formed between the sheath tube 30 and the flame tube 20.

In the intermediate space 40, a plurality (exactly eight here) of circumferentially of the two tubes (flame tube 20 and sheath tube 30) distributed identical guide ribs 50 are provided, each radially between the sheath tube 30 and flame tube 20 and parallel to and along a longitudinal direction LR of Jacket tube 30 and flame tube 20 extend so that the gap 40 through the guide ribs 50 in a plurality of substantially over the entire provided with through holes 31 length the sheathing tube 30 extending longitudinal channels 41 is divided with each kreisringsektorförmigem cross-section.

The guide ribs 50 reliably prevent the air flowing radially in the operating case via the passage openings 31 in the intermediate space 40 from obtaining a circumferential or rotating flow component around the flame tube 20. As a result, the air flow can be distributed more uniformly around the flame tube 20 and the cooling of the flame tube 20 is improved. In addition, the air after the deflection (by hitting the flame tube 20) is channeled from radial to axial flow in the longitudinal channels 41, so that the inflow to a subsequent combustion zone (not shown) can be made homogeneous.

The guide ribs 50 are attached (e.g., welded) to the inner circumference of the sheath tube 30, with each guide rib 50 extending radially such that a gap S is formed between the guide rib 50 and the flame tube 20. The gap S has just such a radial width, that during operation of the gas turbine 1 different heat-related material expansions of flame tube 20. Sheath tube 30 and baffles 50 can be compensated without pressurizing the guide ribs 50 on the flame tube 20.

The guide ribs 50 are each in the form of a sheet-metal strip, with their respective width extending radially and their respective length axially or in the longitudinal direction LR of the sheath tube 30 and the flame tube 20. The thickness of the respective guide ribs 50 is about 3 mm.

As in particular from Figure 3 (Left half of the figure), the guide ribs 50 and the through holes 31 formed in the wall of the jacket tube 30 are arranged so that the guide ribs 50 do not close any of the through holes 31.

As in particular from the FIGS. 1 and 2 As can be seen, the guide ribs 50 are arranged at different circumferentially angular intervals from one another in the intermediate space 40.

The guide ribs 50 in this case have a first group of guide ribs 50 (which in FIG Fig.2 on the left of a symmetry axis Y of the flame tube 20) and a second group of guide ribs 50 (shown in Figs Fig.2 right of the axis of symmetry Y are arranged) on. According to the shown embodiment of the invention, the first group of guide ribs 50 are arranged in a predetermined first arrangement pattern with respect to their mutual circumferential angular distance, the second group of guide ribs 50 being arranged in a second arrangement pattern with respect to their mutual circumferential angular distance, which is a reflection of the first arrangement pattern at the symmetry axis Y represents.

According to the in Fig.2 1, the predetermined first arrangement pattern of the first group of guide ribs 50 is defined by the angular dimensions: a = 27 degrees, b = 1.8 degrees, c = 34.2 degrees and d = 59.4 degrees. The second array pattern of the second group of guide ribs 50 is defined by the angular dimensions: a '= 27 degrees, b' = 1.8 degrees, c '= 34.2 degrees, and d' = 59.4 degrees.

In other words, according to Fig.2 in each group of baffles 50, a combination of angular spacings between the baffles 50 of 28.2 degrees, 32.4 degrees and 25.2 degrees, the two groups of baffles 50 having an angular separation of 61.2 degrees (in Fig.2 below) or 126 degrees (in Fig.2 above).

According to other embodiments of the invention, not shown, the first and second arrangement patterns could also be completely different be. The specific realization of the first and second arrangement pattern or of the respective angular spacing of the guide ribs 50 may depend on the respective, for example, dimensional and / or formal configuration of the gas turbine 1 and thus be adaptable in accordance with the specific flow conditions occurring there.

In Figure 4 In FIG. 2, a comparison of the air flow and pressure distributions in the combustion chamber housing 10 is shown in two cross-sectional views, wherein the combustion chamber housing according to the in Figure 4 upper illustration without guide fins 50 and the combustion chamber housing according to the in Figure 4 bottom view according to the invention with guide ribs 50 is executed.

As seen from the upper illustration of Figure 4 can be seen without guide ribs 50 in the operation of the gas turbine 1 due to the circumferential flow around the flame tube 20 in the gap 40 inhomogeneous Luftströmungs- and pressure conditions.

As from the lower part of Figure 4 can be seen standing with the transverse to the direction of flow of the incoming air guide baffles 50 during operation of the gas turbine 1 due to the thus obtained Unterbindens the circumferential flow around the flame tube 20 in the space 40 substantially homogeneous Luftströmungs- and pressure conditions, whereby a uniform distribution of the incoming Air is achieved around the flame tube 20 and the cooling of the flame tube 20 is improved. In addition, the air is channel-shaped after the deflection from radial to axial flow, so that the inflow to the subsequent combustion zone is homogeneous.

LIST OF REFERENCE NUMBERS

1

gas turbine

10

combustion chamber housing

20

flame tube

30

sheathing tube

31

Through openings

40

gap

41

longitudinal channel

50

guiding rib

S

gap

LR

longitudinal direction

Y

axis of symmetry

a, b, c, d

square

a ', b', c ', d'

square

Claims (8)

1. A combustion chamber housing (10) of a gas turbine (1) with:

   a flame tube (20), and a jacket tube (30), which surrounds the flame tube (20) and which in its wall has a plurality of passage openings (31), via which air flowing onto the jacket tube (30) on the outside can radially enter an intermediate space (40) formed between the jacket tube (30) and the flame tube (20), a plurality of flow guiding ribs (50) arranged circumferentially distributed in the intermediary space (40) of the two tubes, which in each case extend radially between jacket tube (30) and flame tube (20) and parallel to a longitudinal direction (LR) of jacket tube (30) and flame tube (20) in such a manner and which are welded to the jacket tube (30), so that the intermediate space (40) through the flow guiding ribs (50) is subdivided into multiple longitudinal channels (41), characterized in that between the flow guiding ribs (50) and the flame tube (20) a gap (S) is formed.
2. The combustion chamber housing (10) according to Claim 1, wherein the flow guiding ribs (50) are each formed strip-shaped.
3. The combustion chamber housing (10) according to Claim 2, wherein the flow guiding ribs (50) have a thickness dimension of 3 mm.
4. The combustion chamber housing (10) according to any one of the Claims 1 to 3, wherein the flow guiding ribs (50) and the passage openings (31) which are formed in the wall of the jacket tube (30) are arranged so that the flow guiding ribs (50) do not close off any of the passage openings (31).
5. The combustion chamber housing (10) according to any one of the Claims 1 to 4, wherein the plurality of flow guiding ribs (50) is formed by exactly eight identical flow guiding ribs (50).
6. The combustion chamber housing (10) according to any one of the Claims 1 to 5, wherein the flow guiding ribs (50) are arranged in the intermediate space (40) with different circumferential angle spacing from one another.
7. The combustion chamber housing (10) according to any one of the Claims 1 to 6, wherein the flow guiding ribs (50) comprise a first group of flow guiding ribs (50) and a second group of flow guiding ribs (50), wherein the first group of flow guiding ribs (50) with respect to its mutual circumferential angular distance are arranged at a predetermined first arrangement pattern, and wherein the second group of flow guiding ribs (50) with respect to their mutual circumferential angular distance are arranged in a second arrangement pattern, which represents a mirror image of the first arrangement pattern on an axis of symmetry (Y) of the flame tube (20).
8. A gas turbine (1) with a combustion chamber housing (10) according to any one of the Claims 1 to 7.

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