Fuel nozzle assembly for reducing multiple tone combustion dynamics

Abstract

A fuel nozzle assembly includes a center body comprising an outer sleeve and an internal fuel passage defined within the outer sleeve. The internal fuel passage defines a fuel flow path within the center body and includes an inlet defined at an upstream end of the center body. The inlet is formed to receive fuel from a fuel supply. The fuel nozzle assembly also includes a plurality of vanes that extend radially outwardly from the outer sleeve and at least one of the vanes includes at least one fuel port that is in fluid communication with the internal fuel passage. At least one baffle extends radially into the internal fuel passage downstream from the inlet and upstream from the at least one fuel port such that the at least one baffle reduces fuel flow area within the fuel flow path upstream from the at least one fuel port.

We claim: 
     
         1 . A fuel nozzle assembly, comprising:
 a center body comprising an outer sleeve and an internal fuel passage defined within the outer sleeve, the internal fuel passage defining a fuel flow path within the center body, wherein the internal fuel passage includes an inlet defined at an upstream end of the center body, wherein the inlet is formed to receive fuel from a fuel supply;   a plurality of vanes that extend radially outwardly from the outer sleeve, at least one of the vanes including at least one fuel port in fluid communication with the internal fuel passage; and   at least one baffle extending radially into the internal fuel passage downstream from the inlet and upstream from the at least one fuel port, wherein the at least one baffle reduces fuel flow area within the internal fuel passage.   
     
     
         2 . The fuel nozzle assembly as claimed in  claim 1 , wherein the at least one baffle extends radially inwardly from the outer sleeve into the fuel flow path. 
     
     
         3 . The fuel nozzle assembly as claimed in  claim 1 , wherein the at least one baffle extends circumferentially about an inner surface of the outer sleeve with respect to a longitudinal axis of the center body. 
     
     
         4 . The fuel nozzle assembly as claimed in  claim 1 , wherein a radially inner portion of the at least one baffle is at least partially triangular, arcuate or wedge shaped. 
     
     
         5 . The fuel nozzle assembly as claimed in  claim 1 , wherein the at least one baffle is disposed proximate to the fuel port and distal from the inlet with respect to a longitudinal axis of the center body. 
     
     
         6 . The fuel nozzle assembly as claimed in  claim 1 , where the at least one baffle is disposed proximate to the inlet and distal from the fuel port with respect to a longitudinal axis of the center body. 
     
     
         7 . The fuel nozzle assembly as claimed in  claim 1 , wherein the at least one baffle comprises a plurality of baffles extending radially into the internal fuel passage downstream from the inlet and upstream from the at least one fuel port, wherein the plurality of baffles are longitudinally spaced apart with respect to a longitudinal axis of the center body. 
     
     
         8 . The fuel nozzle assembly as claimed in  claim 1 , further comprising an outer shroud that circumferentially surrounds at least a portion of the center body, wherein the plurality of vanes extend from the center body and are connected to the outer shroud. 
     
     
         9 . The fuel nozzle assembly as claimed in  claim 1 , further comprising a flow restrictor disposed upstream from the inlet to the internal fuel passage. 
     
     
         10 . A combustion system, comprising:
 an end cover coupled to an outer casing and in fluid communication with a fuel supply;   a plurality of fuel nozzle assemblies spaced radially and circumferentially across an inner surface of the end cover, wherein the plurality of fuel nozzle assemblies includes a first fuel nozzle assembly in fluid communication with a first fuel circuit and a second fuel nozzle assembly in fluid communication with a second fuel circuit, wherein the first fuel nozzle assembly comprises:
 a center body comprising an outer sleeve and an internal fuel passage defined within the outer sleeve, the internal fuel passage defining a fuel flow path within the center body, wherein the internal fuel passage includes an inlet defined at an upstream end of the center body and in fluid communication with the first fuel circuit; 
 a plurality of vanes that extend radially outwardly from the outer sleeve, at least one of the vanes including at least one fuel port in fluid communication with the internal fuel passage; and 
 at least one baffle extending radially into the internal fuel passage downstream from the inlet and upstream from the at least one fuel port, wherein the at least one baffle reduces fuel flow area within the fuel flow path. 
   
     
     
         11 . The combustion system as claimed in  claim 10 , wherein the at least one baffle extends radially inwardly from the outer sleeve into the fuel flow path. 
     
     
         12 . The combustion system as claimed in  claim 10 , wherein the at least one baffle extends circumferentially about an inner surface of the outer sleeve with respect to a longitudinal axis of the center body. 
     
     
         13 . The combustion system as claimed in  claim 10 , wherein the at least one baffle is disposed proximate to the fuel port and distal from the inlet with respect to a longitudinal axis of the center body. 
     
     
         14 . The combustion system as claimed in  claim 10 , the at least one baffle is disposed proximate to the inlet and distal from the fuel port with respect to a longitudinal axis of the center body. 
     
     
         15 . The combustion system as claimed in  claim 10 , wherein the at least one baffle comprises a plurality of baffles extending radially into the internal fuel passage downstream from the inlet and upstream from the at least one fuel port, wherein the plurality of baffles are longitudinally spaced apart with respect to a longitudinal axis of the center body. 
     
     
         16 . The combustion system as claimed in  claim 10 , further comprising a flow restrictor disposed within the first fuel circuit upstream from the inlet to the internal fuel passage. 
     
     
         17 . The combustion system as claimed in  claim 10 , wherein the second fuel nozzle assembly comprises:
 a center body comprising an outer sleeve and an internal fuel passage defined within the outer sleeve, the internal fuel passage defining a fuel flow path within the center body, wherein the internal fuel passage includes an inlet defined at an upstream end of the center body and in fluid communication with the second fuel circuit;   a plurality of vanes that extend radially outwardly from the outer sleeve, at least one of the vanes including at least one fuel port in fluid communication with the internal fuel passage; and   at least one baffle extending radially into the internal fuel passage downstream from the inlet and upstream from the at least one fuel port, wherein the at least one baffle reduces fuel flow area within the fuel flow path.   
     
     
         18 . The combustion system as claimed in  claim 17 , further comprising at least one flow restrictor disposed within at least one of the first fuel circuit and the second fuel circuit upstream from the corresponding inlet to the internal fuel passage of the first fuel nozzle assembly or the inlet of the second fuel nozzle assembly. 
     
     
         19 . The combustion system as claimed in  claim 17 , wherein the at least one baffle of the first fuel nozzle assembly is positioned within the internal fuel passage of the first fuel nozzle assembly at a first longitudinal distance from the inlet of the internal fuel passage of the first fuel nozzle assembly, and the at least one baffle of the second fuel nozzle assembly is positioned within the internal fuel passage of the second fuel nozzle assembly at a second longitudinal distance from the inlet of the internal fuel passage of the second fuel nozzle assembly. 
     
     
         20 . The combustion system as claimed in  claim 19 , wherein the first longitudinal distance is greater than or less than the second longitudinal distance.