Gas turbine

Abstract

The present invention relates to a gas turbine, in particular an aircraft engine gas turbine having a shaft and a bladed turbine rotor joined therewith that has a first rotor segment which has a downstream rotating cascade of the turbine rotor and bounds a first space in the radial direction, this first space communicating with a first gas passage disposed in the shaft, and has a second rotor segment axially adjacent to the first rotor segment, which has at least one second rotating cascade of the turbine rotor and bounds in the radial direction a second space axially adjacent to the first space, this second space communicating with a second gas passage, wherein the first rotor segment has at least one first discharge opening for the discharge of gas from the first space upstream of the furthest downstream rotating cascade.

Claims

1. A gas turbine, comprising: a shaft and a bladed turbine rotor joined therewith; a first rotor segment, which has a downstream rotating cascade of the bladed turbine rotor and bounds a first space in the radial direction, the first space communicating with a first gas passage disposed in the shaft; and a second rotor segment axially adjacent to the first rotor segment, which has at least one second rotating cascade of the bladed turbine rotor and bounds a second space axially adjacent to the first space in the radial direction, this second space communicating with a second gas passage; wherein the first rotor segment has at least one discharge opening for the discharge of gas from the first space upstream of the furthest downstream rotating cascade, and wherein the first space is bounded downstream in the axial direction by a cover directly fastened to the rotor, this cover engaging over, at least partially, a downstream front side of the shaft in the radial direction.

2. The gas turbine according to claim 1, wherein the cover is fastened detachably to the turbine rotor.

3. The gas turbine according to claim 1, wherein the first gas passage communicates with the first space via the at least one discharge opening in the shaft, in a downstream front side of the shaft.

4. The gas turbine according to claim 1, wherein the first space is bounded upstream in the axial direction by a rotor cone, which joins the turbine rotor to the shaft, and widens, running from an inlet to an outlet of the turbine rotor, counter to a direction of through-flow.

5. The gas turbine according to claim 1, wherein the first rotor segment has at least one additional rotating cascade of the turbine rotor and at least one additional discharge opening for the discharge of gas from the first space upstream or downstream of the additional rotating cascade.

6. The gas turbine according to claim 1, wherein the second rotor segment has at least one second discharge opening for the discharge of gas from the second space upstream or downstream of the second rotating cascade.

7. The gas turbine according to claim 1, wherein the first gas passage communicates with a first pressure source, in particular, a first compressor stage of the gas turbine; and the second gas passage communicates with a second pressure source, in particular, a second compressor stage of the gas turbine, which has a higher pressure than the first pressure source.

8. The gas turbine according to claim 1, wherein a proportion of a boundary surface fixed relative to the rotor, with respect the total boundary surface of the first space, is at least 80%.

9. The gas turbine according to claim 1, wherein the first space is supplied with a first gas flow through the first gas passage, and the second space is supplied with a second gas flow through the second gas passage.

10. The gas turbine according to claim 9, wherein at least 80% of the first gas flow is discharged from the first space through the first discharge openings.

11. The gas turbine according to claim 1, wherein the first space has a first gas pressure and the second space has a second gas pressure, the second gas pressure is at least 50 kPa higher than the first gas pressure or amounts to at least 400 kPa.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) Additional advantageous enhancements of the present invention can be taken from the dependent claims and the following description of preferred embodiments. For this purpose and partially schematized:

(2) FIG. 1 shows a portion of a gas turbine according to an embodiment of the present invention.

DESCRIPTION OF THE INVENTION

(3) FIG. 1 shows a portion of a gas turbine according to one embodiment of the present invention in an axial section.

(4) The gas turbine has a shaft 1 and a bladed turbine rotor 20 joined therewith in a rotationally-resistant and axially-fixed manner.

(5) The turbine rotor 20 has a first rotor segment 21, which has a furthest downstream rotating cascade 23 as well as another rotating cascade 24 distanced in the axial direction (horizontal in FIG. 1), and this rotating cascade 24 is disposed upstream (left in FIG. 1) of the furthest downstream rotating cascade 23.

(6) The turbine rotor 20 has a second rotor segment 22 bounding thereto or axially adjacent upstream of the first rotor segment 21 (left in FIG. 1), and this second rotor segment 22 has in turn at least one second rotating cascade 25 of the turbine rotor.

(7) The first and second rotor segments are separated from one another by a common third rotating cascade 26.

(8) The rotating cascades 23-26 of the bladed turbine rotor are disposed in a common flow channel 3, which is bounded radially inward in the radial direction (vertical in FIG. 1) at least partially by the turbine rotor.

(9) The first rotor segment 21 bounds a first space 41 from radially outside in the radial direction (top in FIG. 1), and this space 41 communicates or is joined aerodynamically to a first gas passage in the form of a first gas passage 51 formed in the shaft 1.

(10) The second rotor segment 22 bounds a second space 42 that is axially adjacent to the first space 41, from radially outside in the radial direction, and this second space 42 communicates aerodynamically with a second gas passage 52 that is aerodynamically separated from the first gas passage 51.

(11) The first rotor segment 21 has several first discharge openings 61 for the discharge of gas from the first space 41 into the flow channel 3 between the furthest downstream rotating cascade 23 and the additional rotating cascade 24 that is axially adjacent to rotating cascade 23, as well as between this additional rotating cascade 24 and the third rotating cascade 26.

(12) The first space 41 is bounded in the axial direction downstream (right in FIG. 1) by a cover 70 fastened to the turbine rotor, and this cover 70 in the radial direction engages over or covers up from radially outside a downstream front side (right in FIG. 1) of shaft 1 over at least 80% of its front surface.

(13) The cover 70 is fastened detachably by screws 71 to the turbine rotor 20 in a friction fit.

(14) The first gas passage 51 communicates aerodynamically with the first space 41 via a central-shaft discharge opening 11 in a downstream front side (right in FIG. 1) of the shaft 1.

(15) The first space 41 is bounded in the axial direction upstream (left in FIG. 1) by a rotor cone 8 and is aerodynamically and structurally separated from the second space 42. The rotor cone 8 joins the turbine rotor 20 to the shaft 1 and widens counter to a direction of through-flow axially, running from a gas-turbine or turbine-rotor inlet to a gas-turbine or turbine-rotor outlet (from left to right in FIG. 1) of the turbine rotor (i.e., converges radially toward the right in FIG. 1).

(16) The second rotor segment 22 has several second discharge openings 62 for the discharge of gas upstream of the second rotating cascade 25 and between this second rotating cascade 25 and the third rotating cascade 26.

(17) The first gas passage 51 communicates aerodynamically with the first compressor stage of the gas turbine; the second gas passage 52 communicates with a second compressor stage of the gas turbine (not shown), which has or supplies a higher pressure than the first compressor stage.

(18) The first space 41 is completely fixed relative to the rotor via the first rotor segment 21, the cover 70 fastened to the rotor, the rotor cone 8, and bounds the shaft 1 joined to the turbine rotor 20, so that the proportion of boundary surface fixed to the rotor of the first space 41 amounts to 100% of its total boundary surface.

(19) During operation, the first space 41 is supplied via the first gas passage 51 with a first flow of cooling air, which is discharged from this first space through the first discharge openings 61 and a vent 63, and the second space 42 is supplied via the second gas passage 52 with a second flow of cooling air, which is discharged from the second space through the second discharge openings 62, as is indicated schematically by arrows depicting flow in FIG. 1. In this case, at least 80% of the first gas flow is discharged from the first space 41 through the first discharge openings 61.

(20) At one operating point, the first space 41 has a first gas pressure of approximately 350 kPa, and the second space has a second gas pressure of approximately 450 kPa.

(21) Although exemplary embodiments were explained in the preceding description, it shall be noted that a plurality of modifications is possible. In addition, it shall be not that the exemplary embodiments only involve examples that in no way shall limit the scope of protection, the applications and the structure. Rather, a guide is given to the person skilled in the art by the preceding description for implementing at least one exemplary embodiment, whereby diverse changes, particularly with respect to the function and arrangement of the described components, can be carried out without departing from the scope of protection, as it results from the claims and combinations of features equivalent to these.