Combustion chamber for a gas turbine

1. A combustion chamber for a gas turbine, the combustion chamber being surrounded by a gas turbine casing inside of which is disposed a plenum filled with compressed air, the plenum surrounding the combustion chamber, and the combustion chamber being separated from the plenum by a combustion chamber casing, the combustion chamber comprising at least one Helmholtz damper for damping thermoacoustic oscillations, the Helmholtz damper having a damping volume in communication with the combustion chamber via a connecting passage, wherein the Helmholtz damper is configured to have a damping frequency that is adjustable, the damping volume being divided into a fixed damping volume arranged inside the combustion chamber casing and being in fluid communication with the combustion chamber, and a variable damping volume arranged within the plenum and being in fluid communication with the combustion chamber, the damping volume being varied by changing the variable damping volume, and the fixed damping volume being selectable so that the damping frequency is proximate a frequency of a thermoacoustic oscillation of the combustion chamber and adjustable by changing the variable damping volume.

2. The combustion chamber of claim 1 , wherein the damping volume of the Helmholtz damper is continuously variable.

3. The combustion chamber of claim 1 , wherein the combustion chamber, on an entry side, has a plurality of burners that open out into the combustion chamber, and the at least one Helmholtz damper is arranged on the entry side, in the immediate vicinity of the burners.

4. A combustion chamber for a gas turbine comprising at least one Helmholtz damper for damping thermoacoustic oscillations, the Helmholtz damper having a damping volume in communication with the combustion chamber via a connecting passage, wherein the Helmholtz damper is configured to have a damping frequency that is adjustable, the damping volume being divided into a fixed damping volume and a variable damping volume, the damping volume being varied by changing the variable damping volume, and the fixed damping volume being selectable so that the damping frequency is proximate a frequency of a thermoacoustic oscillation of the combustion chamber and adjustable by changing the variable damping volume;

wherein the damping volume of the Helmholtz damper is continuously variable; and

wherein the variable damping volume is delimited on one side by a displaceable piston.

5. A combustion chamber for a gas turbine comprising:

at least one Helmholtz damper for damping thermoacoustic oscillations, the Helmholtz damper having a damping volume in communication with the combustion chamber via a connecting passage, the Helmholtz damper being configured to have an adjustable damping frequency, the damping volume of the Helmholtz damper being continuously variable, the damping volume being divided into a fixed damping volume and a variable damping volume, and the damping volume being varied by changing the variable damping volume, the variable damping volume being delimited on one side by a displaceable piston; and

an adjustment element arranged at the Helmholtz damper, the adjustable element being in the form of a threaded rod by means of which the piston can be displaced.

6. The combustion chamber of claim 5 , wherein the combustion chamber is disposed inside a turbine casing and the adjustment element can be actuated through a closeable access opening in the turbine casing.

7. A combustion chamber for a gas turbine comprising at least one Helmholtz damper for damping thermoacoustic oscillations, the Helmholtz damper having a damping volume in communication with the combustion chamber via a connecting passage, wherein the Helmholtz damper is configured to have an adjustable damping frequency, the combustion chamber, on an entry side, has a plurality of burners that open out into the combustion chamber, the at least one Helmholtz damper is arranged on the entry side, in the immediate vicinity of the burners, the combustion chamber is annular, the burners are arranged in concentric rings, and the at least one Helmholtz damper is arranged between the rings in a radial direction.

8. A combustion chamber for a gas turbine, the combustion chamber being surrounded by a gas turbine casing inside of which is disposed a plenum filled with compressed air, the plenum surrounding the combustion chamber, and the combustion chamber being separated from the plenum by a combustion chamber casing, the combustion chamber comprising a Helmholtz damper for damping thermoacoustic oscillations, the Helmholtz damper forming a damping resonator in communication with the combustion chamber and having an adjustable damping volume, the damping volume being divided into a fixed damping volume arranged inside the combustion chamber casing and being in fluid communication with the combustion chamber, and a variable damping volume arranged within the plenum and being in fluid communication with the combustion chamber, the damping volume being varied by changing the variable damping volume, and the fixed damping volume being selectable so that a damping frequency of the Helmholtz damper is proximate a frequency of a thermoacoustic oscillation of the combustion chamber and adjustable by changing the variable damping volume.

9. The combustion chamber of claim 8 , wherein the damping resonator comprises a connecting passage in communication with the adjustable damping volume.

10. The combustion chamber of claim 8 , wherein the damping frequency of the Helmholtz damper is continuously adjustable.

11. The combustion chamber of claim 8 , further comprising a plurality of burners that open out on an entry side of the combustion chamber, wherein the Helmholtz damper is disposed proximate the burners.

12. The combustion chamber of claim 8 , wherein the fixed damping volume is cylindrical and the variable damping volume is cylindrical.

13. A combustion chamber for a gas turbine comprising a Helmholtz damper for damping thermoacoustic oscillations, the Helmholtz damper forming a damping resonator in communication with the combustion chamber and having an adjustable damping volume, the damping volume being divided into a fixed damping volume and a variable damping volume, the damping volume being varied by changing the variable damping volume, and the fixed damping volume being selectable so that a damping frequency of the Helmholtz damper is proximate a frequency of a thermoacoustic oscillation of the combustion chamber and adjustable by changing the variable damping volume, wherein the Helmholtz damper comprises a piston for adjusting the damping volume.

14. A combustion chamber for a gas turbine comprising a Helmholtz damper for damping thermoacoustic oscillations, the Helmholtz damper forming a damping resonator in communication with the combustion chamber and having an adjustable damping volume, the combustion chamber further comprising a plurality of burners, wherein the combustion chamber is annular, the burners are arranged in concentric rings, and the Helmholtz damper is arranged between the rings in a radial direction.

15. A combustion chamber for a gas turbine, the combustion chamber being surrounded by a gas turbine casing inside of which is disposed a plenum filled with compressed air, the plenum surrounding the combustion chamber, and the combustion chamber being separated from the plenum by a combustion chamber casing, the combustion chamber comprising:

a plurality of burners; and

a Helmholtz damper that forms a damping resonator in communication with the combustion chamber and is configured and located to damp thermoacoustic oscillations excited in the combustion chamber during a combustion operation;

wherein the Helmholtz damper has a continuously adjustable damping frequency and a damping volume divided into a fixed damping volume arranged inside the combustion chamber casing and being in fluid communication with the combustion chamber and a variable damping volume arranged within the plenum and being in fluid communication with the combustion chamber.