Annular combustor with tangential cooling air injection

Abstract

The combustion dynamics and efficiency of gas turbine having an annular combustor 26 provided with fuel injection nozzles 50 that inject fuel generally tangentially is improved by providing the walls 32, 34, 39 of the combustion 26 with cooling air film injectors 70, 86; 72, 88; 74, 90 at substantially equally angularly spaced locations about each such wall and which are oriented to generally tangentially inject a film-like air stream on the associated wall 32, 34, 39.

We claim: 
     
       1. A gas turbine comprising: a rotor including compressor blades and turbine blades;   an inlet adjacent one side of said compressor blades;   a diffuser adjacent the other side of said compressor blades;   a nozzle adjacent said turbine blades for directing hot gasses at said turbine blades to cause rotation of said rotor;   an annular combustor having radially inner and outer walls connected by a generally radially extending wall about said rotor and having an outlet connected to said nozzle and a primary combustion annulus defined by said walls remote from said outlet, a plurality of fuel injectors to said primary combustion annulus and being substantially equally .[.angular.]. .Iadd.angularly .Iaddend.spaced therearound and configured to inject fuel into said primary combustion annulus in a nominally tangential direction; and   means .[.associated with.]. .Iadd.on .Iaddend.each of said walls for injecting a film-like stream of cooling air into said primary combustion annulus in a generally tangential direction.   
     
     
       2. The gas turbine of claim 1 wherein said .Iadd.cooling air .Iaddend.injection means include cooling air openings in fluid communication with said diffuser to receive compressed gas therefrom. 
     
     
       3. The gas turbine of claim 2 wherein a compressed gas housing surrounds said combustor in spaced relation thereto and is in fluid communication with said diffuser, said cooling air openings extending to the interface of said housing .[.an.]. .Iadd.and said .Iaddend.combustor to receive compressed gas therefrom. 
     
     
       4. The gas turbine of claim 1 wherein said fuel injectors comprise fuel nozzles having ends within said primary combustion annulus, and atomizing nozzles for said combustion supporting gas surrounding said ends. 
     
     
       5. A gas turbine comprising a rotor including compressor blades and turbine blades;   an inlet adjacent one side of said compressor blades:   a diffuser adjacent the other side of said compressor blades:   a nozzle adjacent said turbine blades for directing hot gasses at said turbine blades to cause rotation of said rotor, and   
     
     
       an annular combustor about said rotor having an outlet to said nozzle, an inner wall and an outer wall spaced therefrom and a connecting radial wall defining an annular combustion space, a plurality of cooling air film injectors at substantially equally angularly spaced locations about each said wall and oriented to inject a film-like air stream on the associated wall generally tangentially to said annular combustion space. 
     
     
       6. The gas turbine of claim 5 wherein each said cooling air film injector comprises a row of openings in the associated wall and a cooling strip having an edge overlying and spaced from said row. 
     
     
       7. The gas turbine of claim 6 wherein said cooling strips each have a cross section in the shape of a flatted "S". 
     
     
       8. The gas turbine of claim 6 wherein the rows and strips associated with said inner and outer walls extend generally axially. 
     
     
       9. The gas turbine of claim 6 wherein the rows and strips associated with said radial wall extend generally radially. .Iadd.10. A gas turbine comprising: a rotary compressor;   a rotary turbine wheel mounted for rotation about an axis and coupled to said compressor to drive the same;   a nozzle adjacent said turbine wheel for directing hot gases thereat to rotate the same;   an annular combustor about said turbine wheel having radially inner and outer walls, a radially extending wall and an outlet connected to said nozzle and opposite said radially extending wall with a primary combustion annulus defined by said walls remote from said outlet: and   a plurality of circumferentially spaced fuel injectors adjacent said radially outer wall and having ends disposed in said primary combustion annulus so as to inject fuel thereinto in a direction nominally tangential to said radially inner wall at radii passing through said axis. .Iaddend. .Iadd.11. The gas turbine of claim 10 wherein said combustor further includes a plurality of circumferentially spaced air injector tubes mounted on said radially outer wall and oriented to direct air into said primary combustion annulus in a direction nominally tangential to said radially inner wall. .Iaddend. .Iadd.12. The gas turbine of claim 11 wherein said fuel injectors are located within at least some of said air injection tubes. .Iaddend. .Iadd.13. A gas turbine comprising:   a rotary compressor;   a rotary turbine wheel mounted for rotation about an axis and coupled to said compressor to drive the same;   a nozzle adjacent said turbine wheel for directing hot gases thereat to rotate the same;   an annular combustor about said turbine wheel having radially inner and outer walls, a radially extending wall and an outlet connected to said nozzle and opposite said radially extending wall with a primary combustion annulus defined by said walls remote from said outlet;   a plurality of circumferentially spaced fuel injectors for injecting fuel into said primary combustion annulus in a nominally tangential direction; and   a plurality of circumferentially spaced air injector tubes mounted on said radially outer wall and oriented to direct air into said primary combustion annulus in a direction nominally tangential to said radially inner wall at radii passing through said axis. .Iadd.14. The gas turbine of claim 13 wherein said fuel injectors are located within at least some of said air injection tubes. .Iadd.15. A gas turbine comprising:   a rotary compressor;   a rotary turbine wheel mounted for rotation about an axis and coupled to said compressor to drive the same;   a nozzle adjacent said turbine wheel for directing hot gases thereat to rotate the same about said axis;   an annular combustor about said turbine wheel having radially inner and outer walls, a radially extending wall and an outlet connected to said nozzle and opposite said radially extending wall with a primary combustion annulus defined by said walls remote from said outlet;   a plurality of circumferentially spaced fuel injectors adjacent said radially outer wall and having ends disposed in said primary combustion annulus so as to inject fuel thereinto in a direction nominally tangential to said radially inner wall at radii passing through said axis;   a plurality of circumferentially spaced air injector tubes mounted on said radially outer wall and oriented to direct air into said primary combustion annulus in a direction nominally tangential to said radially inner wall at radii passing through said axis; and   at least some of said air injection tubes being in surrounding relation to one of said fuel injector so that air flowing through said air injection tubes assists in atomizing fuel injected by said injectors. .Iaddend.