Gas turbine engine and fuel injector assembly therefor

Abstract

A gas turbine engine, comprising a compressor section, combustion section, and turbine section in serial flow arrangement, with the combustion section comprising: a combustor liner at least partially defining a combustion chamber; and a fuel injector assembly comprising a mixing tube having a mixing tube body defining a mixing channel. The mixing tube body can have a set of fuel passages terminating in fuel orifices fluidly coupled to the mixing channel. A set air flow passages terminating in air outlets can be fluidly coupled to the mixing channel. At least some of the air outlets circumscribe a corresponding fuel orifice.

1 . A gas turbine engine comprising:
 a compressor section, a combustion section, and a turbine section in serial flow arrangement, the combustion section comprising:
 a combustor liner at least partially defining a combustion chamber; and 
 a fuel injector assembly comprising:
 a mixing tube having a mixing tube body defining a centerline with an inner surface at least partially defining a mixing channel, the mixing channel having an outlet fluidly coupled to the combustion chamber; 
 a set of fuel passages having a set of fuel orifices circumferentially arranged along the inner surface, the set of fuel orifices directed towards the centerline of the mixing tube body; 
 a fuel manifold communicating with the set of fuel passages; and 
 a set of air flow passages having a set of air outlets arranged on the inner surface, with the air outlets in the set of air outlets circumscribing corresponding fuel orifices in the set of fuel orifices, and each of the air flow passages of the set of air flow passages circumscribing a corresponding one of the set of fuel passages, wherein a portion of each of the air flow passages of the set of air flow passages extends partially about an upstream end of the fuel manifold to the corresponding fuel orifice in the set of fuel orifices. 
 
   
     
     
         2 . The gas turbine engine of  claim 1 , wherein the air outlets in the set of air outlets are annular. 
     
     
         3 . The gas turbine engine of  claim 2 , wherein the corresponding fuel orifices are centered within the air outlets. 
     
     
         4 . The gas turbine engine of  claim 3 , wherein the set of air outlets includes an air outlet for each fuel orifice. 
     
     
         5 . (canceled) 
     
     
         6 . The gas turbine engine of  claim 1 , wherein the fuel manifold is at least partially defined by the mixing tube body; and
 wherein the set of fuel passages extend from the fuel manifold to the mixing channel.   
     
     
         7 . The gas turbine engine of  claim 6 , wherein the fuel manifold has an annular configuration about the mixing channel. 
     
     
         8 . The gas turbine engine of  claim 1 , wherein the set of fuel passages further comprises a set of fuel tips; and
 wherein the set of fuel tips extend to the set of fuel orifices.   
     
     
         9 . The gas turbine engine of  claim 1 , further comprising one or more turbulators having protrusions extending into the mixing channel. 
     
     
         10 . The gas turbine engine of  claim 9 , wherein the one or more turbulators is upstream of the set of fuel orifices. 
     
     
         11 . The gas turbine engine of  claim 9 , wherein there is a corresponding turbulator for each fuel orifice. 
     
     
         12 . The gas turbine engine of  claim 1 , wherein the set of air outlets is a set of first air outlets, and the fuel injector assembly includes a set of second air outlets at least partially upstream of the set of first air outlets. 
     
     
         13 . The gas turbine engine of  claim 12 , wherein at least one second air outlet in the set of second air outlets is in an offset configuration with a corresponding first air outlet in the set of first air outlets. 
     
     
         14 . The gas turbine engine of  claim 12 , wherein at least one second air outlet in the set of second air outlets is in an overlapping configuration with a corresponding first air outlet in the set of first air outlets. 
     
     
         15 . The gas turbine engine of  claim 12 , wherein the set of second air outlets includes at least one second air outlet in an offset configuration and at least one second air outlet in an overlapping configuration with corresponding first air outlets in the set of first air outlets. 
     
     
         16 . A fuel injector assembly for a gas turbine engine comprising:
 a mixing tube having a mixing tube body defining a centerline with an inner surface at least partially defining a mixing channel, the mixing channel having an outlet fluidly coupled to a combustion chamber;   a set of fuel passages having a set of fuel orifices circumferentially arranged along the inner surface, the fuel orifices directed towards the centerline of the mixing tube body;   a fuel manifold communicating with the set of fuel passages; and   a set of air flow passages having a set of air outlets arranged on the inner surface, with the air outlets in the set of air outlets circumscribing corresponding fuel orifices in the set of fuel orifices, each air flow passage of the set of air flow passages circumscribing a corresponding fuel passage of the set of fuel passages, wherein a portion of each of the air flow passages of the set of air flow passages extend partially about an upstream end of the fuel manifold to the corresponding fuel orifice in the set of fuel orifices.   
     
     
         17 . The fuel injector assembly of  claim 16 , wherein the air outlets are annular. 
     
     
         18 . The fuel injector assembly of  claim 17 , wherein the fuel orifices are centered within the air outlets. 
     
     
         19 . (canceled) 
     
     
         20 . The fuel injector assembly of  claim 16 , wherein the set of air outlets is a set of first air outlets, and the fuel injector assembly includes a set of second air outlets at least partially upstream the set of first air outlets, the set of second air outlets comprising at least one of:
 a second air outlet in an offset configuration with a corresponding first air outlet in the set of first air outlets, or   a second air outlet in an overlapping configuration with a corresponding first air outlet in the set of first air outlets.   
     
     
         21 . A fuel injector assembly for a gas turbine engine comprising:
 a mixing tube having a mixing tube body defining a centerline and having an inner surface at least partially defining a mixing channel, the mixing tube body at least partly defining a fuel manifold and fuel passages that extend radially inwardly from the fuel manifold towards the centerline, the mixing channel having an outlet fluidly coupled to a combustion chamber, each of the fuel passages communicating with a fuel orifice that is directed towards the centerline such that the fuel orifices are circumferentially arranged along the inner surface of the mixing tube body; and   air flow passages defined by the mixing tube body, each of the air flow passages circumscribing one of the fuel passages, and at least a portion of the each of the air flow passages extending partially about an upstream end of the fuel manifold to a corresponding fuel orifice of the fuel orifices, each of the air flow passages having an air outlet that circumscribes one of the fuel orifices.   
     
     
         22 . The fuel injector assembly of  claim 21 , wherein each of the fuel orifices is centered within the one of the air outlets.