Fuel nozzel

Abstract

The present application provides a fuel nozzle for mixing a flow of fuel and a flow of air. The fuel nozzle may include a downstream face, a number of fuel passages positioned about the downstream face for the flow of fuel, and a nozzle collar position about the downstream face. The nozzle collar may include a number of air vanes for the flow of air and one or more purge holes therethrough.

We claim: 
     
         1 . A fuel nozzle for mixing a flow of fuel and a flow of air, comprising:
 a downstream face;   a plurality of fuel passages positioned about the downstream face for the flow of fuel therethrough;   a nozzle collar position about the downstream face;   the nozzle collar comprising a plurality of air vanes for the flow of air therethrough; and   one or more of the plurality of air vanes comprising one or more purge holes therethrough.   
     
     
         2 . The fuel nozzle of  claim 1 , further comprising an outer tube with the plurality of fuel passages extending therethrough to the downstream face. 
     
     
         3 . The fuel nozzle of  claim 1 , wherein the downstream face comprises a fuel nozzle tip positioned thereon. 
     
     
         4 . The fuel nozzle of  claim 3 , wherein the fuel nozzle tip comprises one or more tip outlets positioned thereon for the flow of fuel and/or the flow of air therethrough. 
     
     
         5 . The fuel nozzle of  claim 4 , wherein the flow of fuel through the plurality of fuel passages comprises a first flow of fuel and wherein the flow of fuel through the one or more tip outlets comprises a second flow of fuel. 
     
     
         6 . The fuel nozzle of  claim 1 , wherein the nozzle collar comprises a downstream ring adjacent to the plurality of air vanes. 
     
     
         7 . The fuel nozzle of  claim 1 , further comprising a plurality of fuel nozzles positioned about a combustion chamber. 
     
     
         8 . The fuel nozzle of  claim 1 , further comprising a flow of purge air through the one or more purge holes. 
     
     
         9 . The fuel nozzle of  claim 8 , wherein the flow of purge air through the one or more purge holes limits a zone of recirculation of the flow of fuel and the flow of air downstream of the fuel nozzle. 
     
     
         10 . The fuel nozzle of  claim 9 , wherein limiting the zone of recirculation of the flow of fuel and the flow of air downstream of the fuel nozzle limits flame holding about the fuel nozzle. 
     
     
         11 . A method of limiting flame holding about a fuel nozzle, comprising:
 providing a flow of fuel through a downstream face of the fuel nozzle;   providing a flow of air through a plurality of air vanes of a nozzle collar of the fuel nozzle;   mixing the flow of fuel and the flow of air downstream of the fuel nozzle;   providing a flow of purge air through a plurality of purge holes in the plurality of air vanes; and   limiting the creation of one or more recirculation zones downstream of the fuel nozzle with the flow of purge air.   
     
     
         12 . The method of  claim 11 , wherein the step of providing a flow of fuel comprises providing a flow of fuel through a plurality of fuel passages. 
     
     
         13 . The method of  claim 11 , wherein the step of providing a flow of fuel comprises providing a flow of fuel through a plurality of tip outlets in a fuel nozzle tip. 
     
     
         14 . The method of  claim 11 , wherein the step of providing a flow of air through a plurality of air vanes comprises providing the flow of air though a plurality of angled air vanes. 
     
     
         15 . The method of  claim 11 , wherein the step of limiting the creation of one or more recirculation zones comprises limiting the creation of one or more recirculation zones extending in a circumferential direction. 
     
     
         16 . A combustor for use with a gas turbine engine, comprising:
 a combustion chamber; and   a plurality of fuel nozzles positioned about the combustion chamber;   each of the plurality of fuel nozzles comprising a nozzle collar thereon;   the nozzle collar comprising one or more air vanes with one or more purge holes therethrough.   
     
     
         17 . The combustor of  claim 16 , wherein each of the plurality of fuel nozzles comprises a plurality of fuel passages for a flow of fuel therethrough, the one or more air vanes for a flow of air therethrough, and the one or more purge holes for a flow of purge air therethrough. 
     
     
         18 . The combustor of  claim 16 , wherein the plurality of fuel nozzles are positioned about an end cover. 
     
     
         19 . The combustor of  claim 16 , wherein each of the plurality of fuel nozzles comprises a downstream face with a plurality of fuel passages extending therethrough. 
     
     
         20 . The combustor of  claim 19 , wherein the downstream face comprises a fuel nozzle tip positioned thereon with one or more tip outlets extending therethrough.