Combustion liner
A liner for a combustor in a gas turbine engine and a related method. The liner includes a liner body having a cold side and a hot side. The liner includes a dilution array having a plurality of dilution passages, each dilution passage of the plurality of dilution passages having a concatenated geometry repeating in a predetermined pattern and extending circumferentially around the liner body. The dilution passage integrates a first dilution air flow flowing through the dilution passage from the cold side to the hot side and a second dilution air flow flowing through the dilution passage from the cold side to the hot side into an integrated dilution air flow and injects the integrated dilution air flow into a core primary combustion zone of the combustor to attain a predetermined combustion state of the combustor. The dilution array is repeated along an axial length of the liner body.
1 . A liner for a combustor in a gas turbine engine, the liner comprising:
a liner body having a cold side and a hot side; and
a dilution array comprising of dilution passages repeating in a predetermined pattern circumferentially around the liner body, each dilution passage of the dilution passages including a concatenated geometry comprising:
a discrete hole configured to inject a first portion of a dilution air flow therethrough from the cold side to the hot side, the discrete hole having a diameter and a centerline extending through a center of the diameter; and
a discrete slot configured to inject a second portion of the dilution air flow therethrough from the cold side to the hot side, the discrete slot having a forward wall and an aft wall substantially parallel to the forward wall, each of the forward wall and the aft wall of the discrete slot having planar surfaces, wherein the centerline of the discrete hole is axially at the aft wall of the discrete slot,
wherein ten percent to ninety percent of a total flow area of each dilution passage is occupied by the discrete hole, and the rest of the total flow area is occupied by the discrete slot, so that the first portion of the dilution air flow is ten percent to ninety percent of a total flow through the dilution passages, and
wherein the dilution array is configured (i) to integrate the first portion of the dilution air flow and the second portion of the dilution air flow into an integrated dilution air flow, and (ii) to inject the integrated dilution air flow into a core primary combustion zone of the combustor to attain a predetermined combustion state of the combustor.
2 . The liner of claim 1 , wherein the dilution array is repeated along an axial length of the liner body.
3 . The liner of claim 1 , wherein the predetermined pattern is a linear array.
4 . The liner of claim 1 , wherein the predetermined pattern comprises a staggered array.
5 . The liner of claim 1 , wherein the discrete slot has a first slot extension extending circumferentially in a first direction from a first side of the discrete hole and a second slot extension extending circumferentially in a second direction from a second side of the discrete hole, wherein the first direction opposes the second direction.
6 . The liner of claim 5 , wherein the first slot extension and the second slot extension are each within a range of 0.5 times to fifteen times a slot width of the discrete slot.
7 . The liner of claim 1 , wherein each of the dilution passages comprises a dilution insert extending radially inward from the hot side of the liner body.
8 . The liner of claim 7 , wherein the dilution insert has (i) a constant height from a forward side of the dilution insert to an aft side of the dilution insert, or (ii) a variable height from a forward side of the dilution insert to an aft side of the dilution insert, or (iii) a height within a range of 0.1 times to ten times the diameter of the discrete hole.
9 . The liner of claim 7 , wherein the dilution insert has a slant cut along a forward side of the dilution insert.
10 . The liner of claim 1 , wherein the discrete hole has a cross section that is a portion of a semi-circle.
11 . The liner of claim 10 , wherein the aft wall of the discrete slot is coextensive with a plane parallel to the aft wall of the discrete slot and extends through the centerline of the portion of the semi-circle of the discrete hole.
12 . The liner of claim 1 , wherein the discrete slots of the dilution passages are circumferentially aligned with one another and are adjacent to one another.
13 . The liner of claim 1 , wherein each discrete slot is located forward of each discrete hole such that each discrete slot is configured to inject the second portion of the dilution air flow forward of a location at which each discrete hole injects the first portion of the dilution air flow, causing the second portion of the dilution air flow to provide hydraulic shielding to the first portion of the dilution air flow, the hydraulic shielding percolating between discrete jets of the first portion of the dilution air flow and enhancing a penetration of the first portion of the dilution air flow into the core primary combustion zone of the combustor.
14 . A liner for a combustor in a gas turbine engine, the liner comprising:
a liner body having a cold side and a hot side; and
a dilution array comprising dilution passages repeating in a predetermined pattern circumferentially around the liner body, each dilution passage of the dilution passages including a concatenated geometry comprising:
a discrete hole configured to inject a first portion of a dilution air flow therethrough from the cold side to the hot side, the discrete hole having a diameter and a centerline extending through a center of the diameter; and
a discrete slot configured to inject a second portion of the dilution air flow therethrough from the cold side to the hot side, the discrete slot having a forward wall and an aft wall substantially parallel to the forward wall, each of the forward wall and the aft wall of the discrete slot having planar surfaces, wherein the centerline of the discrete hole is axially aft of the aft wall of the discrete slot or axially forward of the forward wall of the discrete slot,
wherein ten percent to ninety percent of a total flow area of each dilution passage is occupied by the discrete hole, and the rest of the total flow area is occupied by the discrete slot, so that the first portion of the dilution air flow is ten percent to ninety percent of a total flow through the dilution passages, and
wherein the dilution array is configured (i) to integrate the first portion of the dilution air flow and the second portion of the dilution air flow into an integrated dilution air flow, and (ii) to inject the integrated dilution air flow into a core primary combustion zone of the combustor to attain a predetermined combustion state of the combustor.
15 . The liner of claim 14 , wherein the second portion of the dilution air flow fills a region of wakes formed behind discrete jets of the first portion of the dilution air flow.
16 . The liner of claim 14 , wherein the discrete hole has a cross section that is a portion of a semi-circle.
17 . The liner of claim 14 , wherein the discrete slots of the dilution passages are circumferentially aligned with one another and are adjacent to one another.
18 . The liner of claim 14 , wherein each discrete slot is located aft of each discrete hole such that each discrete slot is configured to inject the second portion of the dilution air flow aft of a location at which each discrete hole injects the first portion of the dilution air flow, causing the second portion of the dilution air flow to provide hydraulic support to the first portion of the dilution air flow, the hydraulic support percolating between discrete jets of the first portion of the dilution air flow and enhancing a penetration of the first portion of the dilution air flow into the core primary combustion zone of the combustor.
19 . The liner of claim 14 , wherein each discrete slot is located forward of each discrete hole such that each discrete slot is configured to inject the second portion of the dilution air flow forward of a location at which each discrete hole injects the first portion of the dilution air flow, causing the second portion of the dilution air flow to provide hydraulic shielding to the first portion of the dilution air flow, the hydraulic shielding percolating between discrete jets of the first portion of the dilution air flow and enhancing a penetration of the first portion of the dilution air flow into the core primary combustion zone of the combustor.