Gas Turbine Combustion Chamber

Abstract

A gas turbine combustion chamber, having a combustion chamber housing, a burner positioned at least partially in the combustion chamber housing and a flame tube positioned in the combustion chamber housing. An upstream end of the flame tube has a flame tube cover. In the region of the flame tube cover radially inside the flame tube cover a mixing tube of the burner extends, which defines a pre-primary combustion zone. Between the mixing tube of the burner and the flame tube cover an axial air flow passage is formed, via which air can be conducted in the axial direction outside along the mixing tube, and into the flame tube cover radial air flow passages are introduced via which the air following the axial air flow passage can be conducted in the radial direction of the flame tube cover for cooling the flame tube cover.

Claims

1. A gas turbine combustion chamber, comprising: a combustion chamber housing; a burner positioned in the combustion chamber housing at least in portions; a flame tube positioned in the combustion chamber housing, that contains a primary combustion zone, a flame tube cover is positioned on an upstream end of the flame tube; a mixing tube of the burner extends in a region of the flame tube cover radially inside adjoining the flame tube cover which at least in portions defines a pre-primary combustion zone; an axial air flow passage is formed between the mixing tube of the burner and the flame tube cover configured for air to be conducted in an axial direction outside along the mixing tube for cooling the mixing tube; and radial air flow passages are introduced into the flame tube cover via which the air following the axial air flow passage can be conducted in a radial direction of the flame tube cover for cooling the flame tube cover.

2. The gas turbine combustion chamber according to claim 1, further comprising inlet openings of the radial air flow passages formed on a radially inner lateral surface of the flame tube cover inlet openings via which the air from the axial air flow passage passes into the radial air flow passages.

3. The gas turbine combustion chamber according to claim 2, further comprising: outlet openings of the radial air flow passages are formed on an axial surface of the flame tube cover facing the primary combustion zone via which the air exits from the radial air flow passages and enters the primary combustion zone.

4. The gas turbine combustion chamber according to claim 3, wherein the outlet openings of the radial air flow passages are formed on a radially outer portion of the axial surface of the flame tube cover.

5. The gas turbine combustion chamber according to claim 3, wherein the radial air flow passages extend between the radially inner inlet openings and the radially outer outlet openings within the flame tube cover.

6. The gas turbine combustion chamber according to claim 3, wherein the radial air flow passages between the radially inner inlet openings and the radially outer outlet openings are closed.

7. The gas turbine combustion chamber according to claim 3, wherein the radial air flow passages between the radially inner inlet openings and the radially outer outlet openings follow a curved or spiral course.

8. The gas turbine combustion chamber according to claim 1, wherein the burner comprises an inlet ring via which the air enters the axial air flow passage formed between the mixing tube of the burner and the flame tube cover.

9. The gas turbine combustion chamber according to claim 8, wherein the inlet ring has radial openings via which the air enters the axial air flow passage in the radial direction.

10. The gas turbine combustion chamber according to any one of the claim 1, wherein a seal is positioned on a downward end of the axial air flow passage between the mixing tube and the flame tube cover.

11. The gas turbine combustion chamber according to claim 1, wherein the flame tube cover is produced by way of a generative manufacturing method.

12. The gas turbine combustion chamber according to claim 10, wherein the generative manufacturing method is 3D printing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Preferred further developments of the invention are obtained from the subclaims and the following description. Exemplary embodiments of the invention are explained in more detail by way of the drawing without being restricted to this. There it shows:

[0011] FIG. 1 is an extract from a gas turbine chamber according to the invention; and

[0012] FIG. 2 is the cross section II-II of FIG. 1.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

[0013] FIG. 1 shows a schematized cross section by way of an extract of a gas turbine combustion chamber 10 according to one aspect of the invention.

[0014] The gas turbine combustion chamber 10 comprises a combustion chamber housing 11, which can also include the baffle grid. In the combustion chamber housing 11, a burner 12 is arranged at least in portions, wherein a burner lid 13 and a swirl generator 14 of the burner 12 are shown. In the swirl generator 14, air and fuel are mixed in order to provide a mixture G of fuel and air.

[0015] In the combustion chamber housing 11, a flame tube 15 is arranged furthermore. The flame tube 15 defines a primary combustion zone 16 of the combustion chamber 10. On the upstream end of the flame tube 15, a flame tube cover 17 is positioned. The flame tube cover 17 essentially comprises two portions 17a, 17b.

[0016] The portion 17a is a plate-shaped portion, which has an axial surface 18 facing the primary combustion zone 16. The portion 17b is a tubular portion into which a mixing tube 19 of the burner 12 extends. The portion 17b of the flame tube cover 17 surrounds the mixing tube 19 of the burner 12 radially outside at least in portions.

[0017] Between the mixing tube 19 and the portion 17b of the flame tube cover 17 an axial air flow passage 20 is formed, through which for cooling the mixing tube 19 air L is conducted in the axial direction along the mixing tube 19. An arrow extending within this axial air flow passage 20 illustrates the flow of the air L in the axial direction through the axial air flow passage 20 outside along the mixing tube 19.

[0018] The mixing tube 19 of the burner 12 defines a so-called pre-primary combustion zone 21 of the gas turbine combustion chamber 10 at least in portions, which is arranged upstream of the primary combustion zone 16 of the gas turbine combustion chamber 10.

[0019] In the flame tube cover 17, namely in the portion 17a of the flame tube cover 17, radial air flow passages 22 are introduced. Air L, which flows via the axial air flow passage 20 for cooling the mixing tube 19, following the axial air flow passage 20, flows for cooling the flame tube cover 17, namely of the portion 17a of the flame tube cover 17, in the radial direction through the flame tube cover 17 via the radial air flow passages 22, which emanating from a radially inner portion of the flame tube cover 17 extend in the direction of a radially outer portion of the flame tube cover 17, namely according to FIG. 2 preferentially curved or bent or spiral.

[0020] As is evident from FIG. 1, inlet openings 24 of the radial air flow passages 22 are formed on a radially inner lateral surface 23 of the flame tube cover 17, namely of the portion 17b of the flame tube cover 17, via which the air L passes from the axial air flow passage 20 into the radial air flow passages 22. On the axial surface 18 of the flame tube cover 17 facing the primary combustion zone 16, namely of the portion 17a of the flame tube cover 17, outlet openings of the radial air flow passages 22 are formed, which are not visible in FIGS. 1 and 2. By way of these outlet openings, air L conducted via the radial air flow passages 22 exits the radial air flow passages 22 and enters the primary combustion zone 16 of the combustion chamber 10, wherein in FIG. 1 arrows show the air L exiting from the outlet openings of the radial air flow passages 22. Accordingly, the air flows out of the flame tube cover 17 radially outside adjacent to the flame tube 15, i.e. in a region of the primary combustion zone 16 that is distant from a flame. This has a positive influence on the CO emission. The CO emission can be reduced.

[0021] The radial air flow passages 22, which emanating from the axial air flow passage 20 extend in the direction of the outlet openings, extend within the portion 17a of the flame tube cover 17 and, between the radially inner inlet openings 24 and the radially outer outlet openings are designed closed. As already explained, the radial air flow passages 22 according to FIG. 2 preferentially follow a bent or spiral course. The air, which at first flows via the axial air flow passage 20 between the mixing tube 19 and the portion 17b of the flame tube 17 and following this via the radial air flow passages 22 of the portion 17a of the flame tube cover 17, enters the axial air flow passage 20 via an inlet ring 26 of the burner 12.

[0022] The inlet ring 26 has radial openings 27 via which the air L enters the axial air flow passage 20 in the direction of the arrow that is visible in FIG. 1 via the radial openings 27 of the inlet ring 26. This occurs on the upstream end of the axial air flow passage 20.

[0023] On the downstream end of the axial air flow passage 20 a seal 28 is positioned via which the axial air flow passage 20 is sealed on its downstream end. By way of this it is ensured that the air, which initially leads via the axial air flow passage 20, enters the radial air flow passages 22 and does not flow directly into the primary combustion zone 16 but only in particular when the air following the axial air flow passage 20 has also flowed via the radial air flow passages 22.

[0024] The seal 28 is preferentially a piston ring seal.

[0025] FIG. 2 shows the cross section II-II through the flame tube cover 17, namely through the portion 17a of the flame tube cover 17, wherein this cross section extends through the radial air flow passages 22 and through the seal 28 and the adjoining portion of the mixing tube 19. The bent course of the radial air flow passages 22 is evident from FIG. 2, which extend from radially inside to radially outside via the portion 17a of the flame tube cover 17. Radially outside adjoining the radial air flow passages 22 a flange portion 25 is formed on the portion 17a of the flame tube cover 17, via which the flame tube cover 17 can be screwed to the flame tube 15.

[0026] The flame tube cover 17 is preferentially a component produced by way of a generative manufacturing method, namely via 3D printing. In the generative manufacturing method, for example laser based powder bed fusion, LBM (laser beam melting) or SLM (selective laser melting)) can be employed.

[0027] According to one aspect of the invention, air that serves for the cooling of the mixing tube 19 is accordingly also conducted through the flame tube cover 17 in order to also cool the flame tube cover 17 following the mixing tube 19. Accordingly, one and the same air is utilised for cooling the mixing tube 19 and the flame tube cover 17. By way of this, an effective cooling can be ensured with a relatively low quantity of air. In addition, the more of air to the burner results in a NOx reduction.

[0028] By way of the defined air conduction the CO emission can be reduced. The air, which was conducted via the axial air flow passage 20 and the radial air flow passages 22 flows in a radially outer portion of the flame tube cover 17 out of the same and accordingly into the primary combustion zone 16 in a radially outer portion, i.e. spaced apart from the flame, as a result of which the CO emission can be reduced.

[0029] Thus, while there have shown and described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.