Cooling of a gas turbine engine downstream of combustion chamber

• US 8,132,417 B2
• Filed: 02/04/2010
• Issued: 03/13/2012
• Est. Priority Date: 08/06/2007
• Status: Active Grant

• Current Assignee: Ansaldo Energia Switzerland AG (Ansaldo Energia SPA)
• Original Assignee: Alstom Technology Ltd. (Alstom SA)
• Inventors: Steiger, Ulrich, Hofmann, Willy Heinz
• Primary Examiner(s): Gartenberg, Ehud
• Assistant Examiner(s): KARNEZOS, NICHOLAS PETER T
• Application Number:
  US12/699,970
• Publication Number:
  US 20100146988A1
• Time in Patent Office: 768 Days
• Field of Search: 608/04, 607/52, 60754-760, 608/06, 608/00, 607/96, 608/05, 415/115, 415/97.R
• US Class Current: 60/806
• CPC Class Codes: F01D 11/001 for sealing space between stator blade and rotor
• CPC Class Codes: F01D 5/143 Contour of the outer or inner working fluid flow path wall, i.e. shroud or hub contour

Abstract

A gas turbine system includes a combustion chamber (2), a turbine (3), a radially inward and/or radially outward axial gap (4; 16, 17) between the combustion chamber (2) and the turbine (3), at which gap inner and/or outer combustion chamber walls (7, 8) and inner and/or outer turbine walls (11, 12) end, and a cooling gas supply (5), which via the gap (4; 16, 17) introduces a cooling gas into the turbine gas path (13) and/or into the combustion chamber gas path (9). An end section (21, 22, 23, 24) of the respective turbine wall (11, 12) and/or of the respective chamber wall (7, 8) adjoining the gap (4; 16, 17) is radially inwardly and/or radially outwardly, alternatingly formed.

Claims

1. A gas turbine system for a utility power plant, the system comprising:

a combustion chamber comprising an inner chamber wall and an outer chamber wall which define an annular outlet region and radially delimit a combustion chamber gas path;

a turbine comprising a turbine inner wall and a turbine outer wall which define a stationary annular inlet region and radially delimit a turbine gas path;

a radially inward, radially outward, or both, axial gap between the combustion chamber and the turbine, at which axial gap the inner chamber wall, the outer chamber wall, or both, and the turbine inner wall, the turbine outer wall, or both, end;

a cooling gas supply, which via the axial gap can introduce a cooling gas into the turbine gas path, into the combustion chamber gas path, or into both;

wherein an end section of a respective turbine wall, of a respective chamber wall, or of both, adjoining the gap is radially inwardly, radially outwardly, or both, formed so that, in the circumferential direction at the gap, positive stages and negative stages alternate;

wherein a positive stage comprises a respective wall situated downstream of the axial gap radially projecting into the respective gas path relative to a respective wall situated upstream of the axial gap;

wherein a negative stage comprises a respective wall situated upstream of the axial gap radially projecting into the respective gas path relative to a respective wall situated downstream of the axial gap; and

wherein a configuration of said circumferentially alternating positive and negative stages is a function of a cooling demand which circumferentially varies and which results at the axial gap during operation of the gas turbine system.

2. A gas turbine system according to claim 1, wherein:

the turbine comprises a first row of guide vanes in the stationary annular inlet region, each guide vane having a pressure side and a suction side; and

a configuration of said circumferentially alternating positive and negative stages is a function of a circumferential distribution of the alternating pressure sides and suction sides of the guide vanes.

3. A gas turbine system according to claim 1, wherein:

the turbine comprises a first row of guide vanes in the stationary annular inlet region, each guide vane having a pressure side and a suction side; and

a configuration of said circumferentially alternating positive and negative stages is a function of bow waves, generated during operation of the gas turbine system, consecutively following one another at intervals in the circumferential direction, and propagating upstream, of the guide vanes.

4. A gas turbine system according to claim 1, wherein a configuration of said circumferentially alternating positive and negative stages is a function of a pressure distribution which varies in the circumferential direction and which results at or in the annular outlet region during operation of the gas turbine system.

5. A gas turbine system according to claim 1, wherein a positive stage comprises:

the inner chamber wall, in an end section adjoining the axial gap, extending radially inwardly relative to circumferentially adjoining regions of the inner chamber wall on both sides of said positive stage;

or

the turbine inner wall, in an end section adjoining the axial gap, extending radially outwardly relative to circumferentially adjoining regions of the turbine inner wall on both sides of said positive stage;

or

both.

6. A gas turbine system according to claim 1, wherein a negative stage comprises:

the inner chamber wall, in an end section adjoining the axial gap, extending radially outwardly relative to circumferentially adjoining regions on both sides of said negative stage;

or

the turbine inner wall, in an end section adjoining the axial gap, extending radially inwardly relative to circumferentially adjoining regions on both sides of said negative stage;

or

both.

7. A gas turbine system according to claim 1, wherein a positive stage comprises:

the outer chamber wall, in an end section adjoining the axial gap, extending radially outwardly relative to circumferentially adjoining regions on both sides of said positive stage;

or

the turbine outer wall, in an end section adjoining the axial gap, extending radially inwardly relative to circumferentially adjoining regions on both sides of said positive stage;

or

both.

8. A gas turbine system according to claim 1, wherein a negative stage comprises:

the outer chamber wall, in an end section adjoining the axial gap, extending radially inwardly relative to circumferentially adjoining regions on both sides of said negative stage;

or

the turbine outer wall, in an end section adjoining the axial gap, extending radially outwardly relative to circumferentially adjoining regions on both sides of said negative stage;

or

both.

9. A gas turbine system according to claim 1, further comprising:

circumferential, continuous transitions between said positive stage and adjoining regions, between said negative stage and adjoining regions, or both, in respective end sections of

the inner chamber wall, or

the outer chamber wall, or

the turbine inner wall, or

the turbine outer wall, or

combinations thereof.