# US 11,994,291 B2 · Performance factor for a combustion liner > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,994,291 B2 - Document ID: US11994291B2 - Status: Granted - Kind: B2 - Application number: 18/060,808 - Filed: 2022-12-01 - Published: 2024-01-25 - Granted: 2024-05-28 - Earliest claimed: 2022-07-21 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Hiranya Nath; Ravindra Shankar Ganiger; Ajoy Patra; Rajendra Wankhade - Web page: https://patentgrep.com/patent/US11994291B2 ## CPC - F23R 3/002: {Wall structures (F23R3/02 and F23R3/007 take precedence)} - F23R 3/06: Arrangement of apertures along the flame tube - F23R 3/16: with devices inside the flame tube or the combustion chamber to influence the air or gas flow - F23R 3/46: Combustion chambers comprising an annular arrangement of {several essentially tubular} flame tubes within a common annular casing or within individual casings - F23R 3/50: Combustion chambers comprising an annular flame tube within an annular casing (toroidal combustion chambers F23R3/52) - F05D 2220/32: in gas turbines - F05D 2240/35: Combustors or associated equipment - F23R: GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS (fluidised bed combustion apparatus specially adapted for operation at superatmospheric pressures F23C10/16) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract An annular combustor includes a combustion liner defining a combustion chamber, the combustion liner having an outer liner and an inner liner and a plurality of dimples in the combustion liner. The combustion liner is characterized by a performance factor greater than or equal to one and less than or equal to seven. An engine includes the annular combustor. ## Claims ### Claim 1 An annular combustor comprising: a combustion liner defining a combustion chamber, the combustion liner having an outer liner and an inner liner; and a plurality of dimples in the combustion liner, the plurality of dimples having at least one outer liner dimple in the outer liner and at least one inner liner dimple in the inner liner, wherein the combustion liner is characterized by a performance factor greater than or equal to one and less than or equal to seven, the performance factor defined by: h ′ h × ∅ θ × DP D × 100 , where h′ is the radial distance between the at least one outer liner dimple and the at least one inner liner dimple, h is the radial distance between the outer liner and the inner liner at the same axial location as the at least one outer liner dimple and the at least one inner liner dimple and at a different circumferential location with no dimple of the plurality of dimples, Ø is a dimple angle of the dimple defined by a first radial axis extending through a first edge of the at least one outer liner dimple or the at least one inner liner dimple and a second radial axis extending through a second edge of the at least one outer liner dimple or the at least one inner liner dimple, θ is a fuel nozzle angle, and DP P is a working fluid pressure drop. ### Claim 2 (depends on 1) The annular combustor of claim 1, wherein the performance factor is greater than or equal to one and less than or equal to three and one-half. ### Claim 3 (depends on 1) The annular combustor of claim 1, wherein the performance factor includes a primary combustion zone performance factor and a post dilution zone performance factor, and wherein each of the primary combustion zone performance factor and the post dilution zone performance factor is greater than or equal to one and less than or equal to seven. ### Claim 4 (depends on 3) The annular combustor of claim 3, wherein the at least one outer liner dimple and the at least one inner liner dimple are located in a primary combustion zone. ### Claim 5 (depends on 3) The annular combustor of claim 3, wherein the at least one outer liner dimple and the at least one inner liner dimple are located in a post dilution zone. ### Claim 6 (depends on 1) The annular combustor of claim 1, wherein the working fluid pressure drop is defined by a fluid pressure at an exit of a compressor and a fluid pressure at an exit of the annular combustor. ### Claim 7 (depends on 1) The annular combustor of claim 1, wherein the working fluid pressure drop is between four percent and seven percent, inclusive of the end points or between 4.5 and 5.4 percent, inclusive of the end points. ### Claim 8 (depends on 1) The annular combustor of claim 1, wherein h ′ h represents a dimple height factor and ∅ θ represents a dimple angular position ratio, and wherein the dimple height factor and the dimple angular position ratio are measured at a plane extending radially through at least one dimple of the plurality of dimples and extending perpendicular to a combustor centerline. ### Claim 9 (depends on 1) The annular combustor of claim 1, wherein h ′ h represents a dimple height factor, the dimple height factor being greater than or equal to 0.1 and less than or equal to 0.9. ### Claim 10 (depends on 9) The annular combustor of claim 9, wherein the dimple height factor is greater than or equal to 0.1 and less than or equal to 0.3. ### Claim 11 (depends on 1) The annular combustor of claim 1, wherein h′ is taken at a maximum height of a dimple of the plurality of dimples. ### Claim 12 (depends on 1) The annular combustor of claim 1, wherein ∅ θ represents a dimple angular position ratio, the dimple angular position ratio being greater than or equal to 0.1 and less than or equal to one. ### Claim 13 (depends on 12) The annular combustor of claim 12, wherein the dimple angular position ratio is greater than or equal to 0.1 and less than or equal to 0.5. ### Claim 14 (depends on 12) The annular combustor of claim 12, wherein the dimple angular position ratio defines a quantity of the plurality of dimples and an angular position of each dimple of the plurality of dimples. ### Claim 15 (depends on 1) The annular combustor of claim 1, wherein the fuel nozzle angle is defined by a number of fuel nozzle assemblies connected to the annular combustor and an angle between a centerline of two adjacent fuel nozzles. ### Claim 16 (depends on 1) A gas turbine engine for an aircraft, comprising: an engine core including one or more turbines, one or more compressors, and the annular combustor of claim 1, the annular combustor disposed downstream of the one or more compressors and upstream of the one or more turbines. ### Claim 17 An annular combustor comprising: a combustion liner defining a combustion chamber, the combustion liner having an outer liner and an inner liner; and a plurality of dimples in the combustion liner, the plurality of dimples having at least one dimple in the outer liner or in the inner liner, wherein the combustion liner is characterized by a performance factor greater than or equal to one and less than or equal to seven, the performance factor defined by: h ′ h × ∅ θ × DP D × 100 , where h′ is the radial distance between the at least one dimple and an inner surface of the other of the outer liner or the inner liner, h is the radial distance between the outer liner and the inner liner at the same axial location as the at least one dimple and at a different circumferential location with no dimple of the plurality of dimples, Ø is a dimple angle of the dimple defined by a first radial axis extending through a first edge of the at least one dimple and a second radial axis extending through a second edge of the at least one dimple, θ is a fuel nozzle angle, and DP P is a working fluid pressure drop. ### Claim 18 (depends on 17) The annular combustor of claim 17, wherein the performance factor is greater than or equal to one and less than or equal to three and one-half.