Combustor with reverse dilution air introduction

1. A combustor for a gas turbine engine comprising:

a forward liner segment having an aft end portion, wherein the forward liner segment defines a primary combustion chamber; and

an aft liner segment having a forward end portion, wherein the forward end portion is disposed within the aft end portion of the forward liner segment, wherein a channel extends radially from an inner surface of the forward liner segment to an outer surface of the aft liner segment, wherein the channel directs a stream of dilution air in a counter-flow direction with respect to combustion gases flowing from the primary combustion chamber during operation of the combustor,

wherein one of the forward liner segment or the aft liner segment comprises a first damping chamber and a second damping chamber, wherein the first and second damping chambers are disposed downstream from the primary combustion chamber and upstream from a secondary combustion chamber at least partially defined by the aft liner segment, and wherein a wall partially defines the channel and one of the first damping chamber or the second damping chamber and separates the channel from the one of the first damping chamber or the second damping chamber.

2. The combustor as in claim 1 , wherein the forward liner segment comprises the first and second damping chambers and further includes a forward inner liner and a forward outer liner, wherein the forward inner liner at least partially defines the first damping chamber, and the forward outer liner at least partially defines the second damping chamber.

3. The combustor as in claim 1 , wherein the forward liner segment comprises the first and second damping chambers, wherein the forward liner segment further comprises a first plurality of inlet apertures in fluid communication with the first damping chamber and a second plurality of inlet apertures in fluid communication with the second damping chamber.

4. The combustor as in claim 3 , wherein the forward liner segment includes a first exhaust aperture in fluid communication with the first damping chamber and the primary combustion chamber, and wherein the forward liner segment further includes a second exhaust aperture in fluid communication with the second damping chamber and the primary combustion chamber.

5. The combustor as in claim 4 , wherein at least one of the first exhaust aperture and the second exhaust aperture directs a stream of cooling air to the forward liner segment during operation of the combustor.

6. The combustor as in claim 1 , wherein the aft liner segment comprises the first and second damping chambers and further includes an aft inner liner and an aft outer liner, wherein the aft inner liner at least partially defines the first damping chamber, and the aft outer liner at least partially defines the second damping chamber.

7. The combustor as in claim 1 , wherein the aft liner segment further comprises a first plurality of inlet apertures in fluid communication with the first damping chamber and a second plurality of inlet apertures in fluid communication with the second damping chamber.

8. The combustor as in claim 7 , wherein the aft liner segment includes a first exhaust aperture in fluid communication with the first damping chamber, and wherein the aft liner segment includes a second exhaust aperture in fluid communication with the second damping chamber, wherein the first and second exhaust apertures are disposed upstream from the secondary combustion chamber.

9. The combustor as in claim 8 , wherein at least one of the first exhaust aperture and the second exhaust aperture directs a stream of cooling air to the aft liner segment during operation of the combustor.

10. A gas turbine engine, comprising:

a fan, a compressor section, a combustor section, and a turbine section, the combustor section including a combustor, the combustor comprising:

a forward liner segment having an aft end portion, wherein the forward liner segment defines a primary combustion chamber; and

an aft liner segment having a forward end portion, wherein the forward end portion is disposed within the aft end portion of the forward liner segment, wherein the aft liner segment at least partially defines a secondary combustion chamber, wherein a channel is defined radially from an inner surface of the aft end portion of the forward liner segment to an outer surface the forward end portion of the aft liner segment, wherein the channel is oriented to direct a stream of dilution air in a counter-flow direction with respect to combustion gases flowing from the primary combustion chamber towards the secondary combustion chamber during operation of the combustor,

wherein one of the forward liner segment or the aft liner segment comprises a first damping chamber and a second damping chamber, wherein the first and second damping chambers are disposed downstream from the primary combustion chamber and upstream from the secondary combustion chamber, and wherein a wall partially defines the channel and one of the first damping chamber or the second damping chamber and separates the channel from the one of the first damping chamber or the second damping chamber.

11. The gas turbine engine as in claim 10 , wherein at least one of the forward liner segment and the aft liner segment defines a plurality of cooling apertures.

12. The gas turbine engine as in claim 10 , wherein the other of the forward liner segment or the aft liner segment comprises a third damping chamber and a fourth damping chamber, wherein the third and fourth damping chambers are disposed downstream from the primary combustion chamber and upstream from the secondary combustion chamber.

13. The gas turbine engine as in claim 10 , wherein the forward liner segment includes the first damping chamber and the second damping chamber, wherein the forward liner segment further comprises a first plurality of inlet apertures in fluid communication with the first damping chamber and a second plurality of inlet apertures in fluid communication with the second damping chamber.

14. The gas turbine engine as in claim 13 , wherein the forward liner segment includes a first exhaust aperture in fluid communication with the first damping chamber and the primary combustion chamber, wherein first exhaust aperture directs a stream of cooling air to the forward liner segment during operation of the combustor.

15. The gas turbine engine as in claim 10 , wherein the aft liner segment comprises the first damping chamber and the second damping chamber.

16. The gas turbine engine as in claim 15 , wherein the aft liner segment further comprises a first plurality of inlet apertures in fluid communication with the first damping chamber and a second plurality of inlet apertures in fluid communication with the second damping chamber.

17. The gas turbine engine as in claim 16 , wherein the aft liner segment includes a first exhaust aperture in fluid communication with the first damping chamber and the primary combustion chamber, and wherein the aft liner segment further includes a second exhaust aperture in fluid communication with the second damping chamber and the primary combustion chamber.

18. The gas turbine engine as in claim 17 , wherein at least one of the first exhaust aperture and the second exhaust aperture of the aft liner segment directs a stream of cooling air to the aft liner segment during operation of the combustor.