초록 ▼

A three stage lean burn combustion chamber (28) comprises a primary combustion zone (36), a secondary combustion zone (40) and a tertiary combustion zone (44). Each of the combustion zones (36, 40, 44) is supplied with premixed fuel and air by respective fuel and air mixing ducts (76, 78, 80, 92). S

A three stage lean burn combustion chamber (28) comprises a primary combustion zone (36), a secondary combustion zone (40) and a tertiary combustion zone (44). Each of the combustion zones (36, 40, 44) is supplied with premixed fuel and air by respective fuel and air mixing ducts (76, 78, 80, 92). Secondary fuel injectors (106) and two secondary fuel manifolds (105A, 105B) supply fuel into different circumferential sectors, halves, of the secondary fuel and air mixing duct (80). The secondary fuel manifolds (105A, 105B) have secondary fuel valves (107A, 107B) which supply a greater proportion of fuel to the secondary fuel manifold (105A) than the secondary fuel manifold (105B) so that there is circumferential biasing of fuel in the secondary combustion zone (40). This circumferential biasing of fuel in the secondary combustion zone (40) reduces the generation of harmful pressure oscillations in the combustion chamber (28). Alternatively the biasing of the fuel may be in the primary or tertiary combustion zones (36, 44).

대표청구항 ▼

A three stage lean burn combustion chamber (28) comprises a primary combustion zone (36), a secondary combustion zone (40) and a tertiary combustion zone (44). Each of the combustion zones (36, 40, 44) is supplied with premixed fuel and air by respective fuel and air mixing ducts (76, 78, 80, 92). S

A three stage lean burn combustion chamber (28) comprises a primary combustion zone (36), a secondary combustion zone (40) and a tertiary combustion zone (44). Each of the combustion zones (36, 40, 44) is supplied with premixed fuel and air by respective fuel and air mixing ducts (76, 78, 80, 92). Secondary fuel injectors (106) and two secondary fuel manifolds (105A, 105B) supply fuel into different circumferential sectors, halves, of the secondary fuel and air mixing duct (80). The secondary fuel manifolds (105A, 105B) have secondary fuel valves (107A, 107B) which supply a greater proportion of fuel to the secondary fuel manifold (105A) than the secondary fuel manifold (105B) so that there is circumferential biasing of fuel in the secondary combustion zone (40). This circumferential biasing of fuel in the secondary combustion zone (40) reduces the generation of harmful pressure oscillations in the combustion chamber (28). Alternatively the biasing of the fuel may be in the primary or tertiary combustion zones (36, 44). n said shroud member has an upstream end portion and a downstream end portion, said upstream end portion defining a leading edge tapering outwardly toward said downstream end portion. 13. The diffuser of claim 9 wherein said shroud member is pinned to said support member. 14. The diffuser of claim 9 wherein said shroud member has an upstream end portion and a downstream end portion, said shroud member including a combustor dome panel attached to said downstream end portion. 15. The diffuser of claim 14 further comprising inner and outer combustor liners spaced apart to define a combustion chamber, said inner and outer combustor liners being coupled to said combustor dome panel. 16. The diffuser of claim 15 wherein said dome panel includes a pair of spaced apart grooves, an end portion of each of said inner and outer combustor liners being captured within a respective one of said grooves. 17. The diffuser of claim 1 wherein said first and second flowpath surfaces each have a surface finish within in a range of about 32 microns to about 64 microns. 18. The diffuser of claim 1 wherein said first structure is comprised of a plurality of circumferential segments interconnected to form a first annular member, said second structure being comprised of a plurality of circumferential segments interconnected to form a second annular member, said first and second annular members being positioned in spaced relation by a plurality of said support members to define an annular flowpath while allowing substantially unrestrained relative displacement between said first and second annular members in a radial direction. 19. A diffuser for a gas turbine engine, comprising: an inner wall; an outer wall spaced from said inner wall to define an annular flowpath; and a plurality of struts coupled between said inner and outer walls to maintain said inner and outer walls in spaced relation while allowing said inner and outer walls to float relative to one another in a radial direction. 20. The gas turbine engine of claim 19 further comprising a plurality of isolation members, each of said isolation members being disposed about a respective one of said plurality of struts to substantially isolate said respective one of said plurality of struts from fluid flow through said annular flowpath. 21. The gas turbine engine of claim 19 wherein each of said inner and outer walls define flowpath surfaces having a surface finish within a range of about 32 microns to about 64 microns. 22. The gas turbine engine of claim 19 wherein each of said plurality of struts includes an end portion coupled to one of said inner and outer walls, said end portion including a first opening and another of said inner and outer walls including a second opening; and further comprising a plurality of pin members, each of said pin members being at least partially disposed within a corresponding pair of said first and second openings to couple each of said struts to said one of said inner and outer walls while allowing said inner and outer walls to float relative to one another in said radial direction. 23. The gas turbine engine of claim 22 wherein each of said plurality of struts includes an opposite end portion rigidly connected to said another of said inner and outer walls, said end portion defining said first opening extending through an aperture defined by said one of said inner and outer walls and being disposed outside of said annular flowpath. 24. The gas turbine engine of claim 19 wherein each of said plurality of struts is radially pinned to at least one of said inner and outer walls to axially couple said inner and outer walls while allowing independent radial displacement therebetween. 25. A diffuser for a gas turbine engine, comprising: a first flowpath structure; a second flowpath structure; a strut coupled to each of said first and second flowpath structures to maintain said first and second flowpath structures in spaced relation to define a flowpath; and