GAS TURBINE HAVING AN ANNULAR PASSAGE SUBDIVIDED INTO ANNULUS SECTORS

Abstract

A gas turbine having at least one inner and outer housing part, between which two housing parts a ring channel is at least partially arranged, which ring channel circumferentially surrounds the useful flow of the working fluid prevailing during operation of the gas turbine and circumferentially surrounds the gas turbine rotor. The ring channel is designed to conduct a cooling fluid in the circumferential direction, wherein the ring channel is divided into ring sectors in the circumferential direction by separators. A tube is at least partially provided in the ring channel which fluidically connects individual ring sectors to each other, and is designed as a distributing tube, which is fluidically connected to at least one cooling-fluid line for conducting cooling fluid and has at least one outlet opening, which at least one outlet opening is designed to transfer the cooling fluid from the tube into the ring sectors.

Claims

1.-10. (canceled)

11. A gas turbine comprising: at least one inner casing part and at least one outer casing part, between which both casing parts is at least partially arranged an annular passage which circumferentially encloses the useful flow of the working fluid, which prevails during operation of the gas turbine, and the gas turbine rotor, wherein the annular passage is designed to direct a cooling fluid in the circumferential direction, wherein the annular passage is fluidically subdivided into annulus sectors in the circumferential direction by partitions, designed as separating plates, which are adapted to prevent a free, unhindered fluid exchange between the individual annulus sectors, wherein provision is made at least partially in the annular passage for a pipe which fluidically interconnects individual annulus sectors, wherein the pipe is designed as a distribution pipe which is fluidically connected to at least one cooling fluid feed line for cooling fluid feed and has at least one outlet opening, which is designed for the transfer of cooling fluid from the pipe into the annulus sectors.

12. The gas turbine as claimed in claim 11, wherein the partitions separate at least individual adjacent annulus sectors from each other in a fluidtight manner.

13. The gas turbine as claimed in claim 11, wherein at least some of the annulus sectors are provided with a separate cooling fluid feed line.

14. The gas turbine as claimed in claim 11, wherein at least individual partitions have penetrations with a cross section in each case.

15. The gas turbine as claimed in claim 11, wherein the annulus sectors have in the main an equal length dimension in the circumferential direction.

16. The gas turbine as claimed in claim 11, wherein an even number of annulus sectors are provided in the circumferential direction.

17. The gas turbine as claimed in claim 11, wherein at least one partition is provided in the region of the upper extremity of the annular passage and/or at least one partition is provided in the region of the lower extremity of the annular passage.

18. The gas turbine as claimed in claim 11, wherein provision is made for at least two partitions which are arranged opposite each other in the circumferential direction of the annular passage.

19. The gas turbine as claimed in claim 11, wherein the partitions are designed as retaining plates, by which the pipe is fastened in the annular passage.

20. The gas turbine as claimed in claim 11, wherein the cooling fluid comprises compressor air.

21. The gas turbine as claimed in claim 11, wherein the distribution pipe has a multiplicity of outlet openings which are designed for the transfer of cooling fluid from the pipe into the annulus sectors.

22. The gas turbine as claimed in claim 18, wherein the at least two partitions are arranged in a rotated manner in relation to the upper extremity of the annular passage by an amount of 85° to 95°.

23. The gas turbine as claimed in claim 11, wherein the partitions separate all the adjacent annulus sectors from each other in a fluidtight manner.

24. The gas turbine as claimed in claim 11, wherein all of the annulus sectors are provided with a separate cooling fluid feed line.

25. The gas turbine as claimed in claim 11, wherein all of the partitions have penetrations with a cross section in each case.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In this case, in the drawing:

[0051] FIG. 1 shows a sectional view from the side in the longitudinal direction through a gas turbine according to the prior art;

[0052] FIG. 2 shows a cross-sectional view through an annular passage in the longitudinal direction along a gas turbine as is known from the prior art;

[0053] FIG. 3 shows a sectional view from the side in the longitudinal direction through an embodiment of a gas turbine as is known from the prior art;

[0054] FIG. 4 shows a cross-sectional view through an annular passage in the longitudinal direction along a gas turbine as is known from the prior art;

[0055] FIG. 5 shows a cross-sectional view through an annular passage in the longitudinal direction along a gas turbine according to an embodiment of the invention;

[0056] FIG. 6 shows a sectional view from the side in the longitudinal direction through an embodiment of a gas turbine which has no pipe and is not claimed in the present case.

DETAILED DESCRIPTION OF INVENTION

[0057] FIG. 1 shows a sectional view from the side in the longitudinal direction through an embodiment of a gas turbine as is known from the prior art. Here, the gas turbine has a compressor 11 which during operation inducts and compresses working fluid 5, that is to say air in the present case. The compressed working fluid 5 is for the most part fed to the combustion chamber 12 for combusting, wherein, however, a small proportion of compressed working fluid 5 in the sense of a cooling fluid 8 is fed to a plenum, which is not additionally provided with a designation, from which this cooling fluid 8 is fed via a secondary fluid line 14 to an annular passage 4. The annular passage 4 is delimited toward the environment by means of an outer casing part 3 and, on the inside, toward the gas turbine rotor 6 by means of an inner casing part 2. In the longitudinal direction of the gas turbine, provision is also made for additional components which form a fluidically delimited annular passage 4.

[0058] During operation of the gas turbine, working fluid is subsequently introduced into the annular passage 4 and, depending on the operating state, can form a larger or smaller flow in the annular passage. The cooling fluid is extracted from the annular passage for further cooling or for sealing purposes, for example. Depending on the operating state of the gas turbine 1, however, the components which delimit the annular passage 4 are heated to a greater or lesser extent. Similarly, those components which are supplied and cooled by means of the cooling fluid 8 which is discharged from the annular passage 4 can be heated to a greater or lesser extent. In both cases, an uneven cooling effect as well as warping or ovalization of the gas turbine are to be feared, as a result of which efficiency is forfeited as already explained further up.

[0059] On account of the uneven heating, as well as sometimes on account of an insufficiently large quantity of cooling fluid 8 introduced into the annular passage 4, relatively large free convection cells can form in the cooling fluid 8 in the annular passage 4, as shown in FIG. 2. These convection cells are shown by dashed lines in the present case. In this case, a free convection cell reaches from a lower extremity point US of the annular passage 4 up to an upper extremity point OS and therefore impairs the entire fluid flow of cooling fluid 8 in the annular passage 4. As a consequence of the forming of the free convection cells, moreover, a disadvantageous temperature distribution occurs inside the annular passage, particularly when only a small cooling fluid quantity 8 exists in the annular passage 4. On account of the flow influences which are brought about as a result of the free convection cells, sometimes not all the regions are sufficiently supplied with a cooling fluid 4 of comparable thermal conditioning. By the same token, cooling fluid 8 can be extracted from the annular passage at predetermined points (not shown in the present case), which cooling fluid can vary with regard to its temperature over the circumferential angle. All this needs to be avoided.

[0060] This can be achieved for example by means of the embodiment shown in FIG. 3. In this case, FIG. 3 shows in the longitudinal direction of the gas turbine 1 a detailed sectional view through altogether three annular passages 4 which are subdivided in each case by means of a partition 7. The partitions 7 define annulus sectors 10, not additionally shown with a designation, (one in each case coming out of the plane of the paper, and one in each case lying behind the plane of the paper,—see also FIG. 4), and therefore enable the interruption or prevention of the forming of large free convection cells in the annular passage 4. The annulus sectors 10 in this case are especially delimited toward the environment by means of the outer casing part 3 and are delimited toward the rotating components of the expansion turbine 13 by means of the inner casing part 2. Since the inner casing parts 2 are heated up more quickly on account of the hot gas flow which is expanded in the expansion turbine 13, these components are also to be acted upon by cooling fluid to an increasing extent.

[0061] FIG. 4 shows a further embodiment of an annular passage 4 of gas turbine 1, which is known from the prior art, in a cross-sectional view along the longitudinal direction of the gas turbine, which annular passage 4 is uniformly subdivided in each case into individual annulus sectors 10 by means of partitions 7. The individual annulus sectors 10 are seen here in each case with a separate cooling fluid feed line 9 via which the individual annulus sectors can be supplied with cooling fluid 8.

[0062] Also in the presently depicted embodiment, individual free convection cells are formed in the cooling fluid 8 which, however, remain limited to the individual annulus sectors 10. As a result, on the one hand a quicker mixing-through of the volume of the annulus sectors 10 can be achieved, moreover a quicker heat transfer to the inner casing part 2 can be achieved since in the annulus sector 10 the flow is on a smaller scale. On account of the partitions 7, the annular passage 4 can therefore be subdivided provided that all regions can be largely supplied with cooling fluid in a comparatively uniform manner. This requires a uniform temperature distribution especially of the inner casing part 2, as a result of which distortion or ovalization of the gas turbine 1 can be largely avoided. In this case, it may be necessary to supply the individual annulus sectors 10 with different quantities of cooling fluid 8 in each case via the cooling fluid feed lines 9. Similarly, different quantities can be extracted again from the respective annulus sectors 10 (not shown in the present case).

[0063] FIG. 5 shows an embodiment of the invention which differs from that shown in FIG. 4 to the extent that for further homogenization of the cooling fluid introduction into the individual annulus sectors 10 provision is made for a pipe 20, designed as a distribution pipe, which extends through all the annulus sectors and via outlet openings 21 transfers the cooling fluid from the interior of the pipe into the individual annulus sectors 10 in each case. The pipe 20, which is designed as a distribution pipe, is itself fed via a cooling fluid feed line 9 with cooling fluid 8. On account of the comparatively smaller flow cross section of the pipe 20, a better oriented flow can be formed in the pipe 20 than in the annular passage 4. Consequently, the cooling fluid 8 in the pipe 20 is sometimes distributed better and more quickly. Moreover, the pressure in the pipe 20 can be increased in comparison to the pressure in the individual annulus sectors 10, as a result of which the transfer of cooling fluid 8 into the individual annulus sectors is determined in the first instance by the pressure drop, and not as a result of possible free convection phenomena in the individual annulus sectors 10.

[0064] According to a further embodiment, which has no pipe 20, it is conceivable, as shown in FIG. 6, to provide the individual partitions 7 of the annular passages 4 with a penetration 15 in each case. The penetration 15 can be designed as a hole, for example, and has a cross-sectional diameter Q in the cross-sectional plane QE which is defined by the planar extension of the partition 7. Via the individual penetrations 15, the annular passages 10 can in each case be in fluid contact with each other so that a cooling fluid exchange can be enabled when required. Depending on the dimensioning of the size of the penetration 15, a larger or smaller quantity of cooling fluid can be exchanged between the adjacent annulus sectors 10 and can therefore contribute to a homogenization of the temperature distribution in the respective annular passage 4.

[0065] Further embodiments result from the dependent claims.