Apparatus and method for mixing fuel in a gas turbine nozzle

Abstract

A nozzle includes a fuel plenum and an air plenum downstream of the fuel plenum. Fuel channels radially outward of an axial centerline of the nozzle include an inlet and an outlet downstream of the inlet. A fuel port in the fuel channels provides fluid communication between the fuel plenum and the fuel channels. An air port in the fuel channels downstream of the fuel port provides fluid communication between the air plenum and the fuel channels. A method for mixing fuel and air in a nozzle prior to combustion includes flowing fuel to a fuel plenum and flowing air to an air plenum downstream of the fuel plenum. The method further includes injecting fuel from the fuel plenum through fuel ports in fuel channels and injecting air from the air plenum through air ports in the fuel channels.

What is claimed is: 
     
         1 . A nozzle comprising:
 a. a fuel plenum;   b. an air plenum downstream of the fuel plenum;   c. a plurality of fuel channels radially outward of an axial centerline of the nozzle, wherein each of the plurality of fuel channels includes an inlet and an outlet downstream of the inlet and allows an air to flow through the inlet;   d. a fuel port in the plurality of fuel channels, wherein the fuel port provides fluid communication between the fuel plenum and the plurality of fuel channels; and   e. an air port in the plurality of fuel channels downstream of the fuel port, wherein the air port provides fluid communication between the air plenum and the plurality of fuel channels.   
     
     
         2 . The nozzle as in  claim 1 , wherein each of the plurality of fuel channels comprises a cylindrical passage that extends from the fuel plenum to the outlet. 
     
     
         3 . The nozzle as in  claim 1 , wherein each of the plurality of fuel channels includes the fuel port. 
     
     
         4 . The nozzle as in  claim 1 , wherein each of the plurality of fuel channels includes the air port. 
     
     
         5 . The nozzle as in  claim 1 , wherein the fuel port is angled approximately 30 to approximately 90 degrees with respect to the axial centerline of the nozzle. 
     
     
         6 . The nozzle as in  claim 5 , wherein the air port is angled less than approximately 30 degrees with respect to the axial centerline of the nozzle. 
     
     
         7 . The nozzle as in  claim 1 , further including a shroud circumferentially surrounding the plurality of fuel channels. 
     
     
         8 . The nozzle as in  claim 7 , further including a barrier inside the shroud, wherein the barrier separates the air plenum from the fuel plenum. 
     
     
         9 . The nozzle as in  claim 7 , wherein the shroud includes at least one air port in fluid communication with the air plenum. 
     
     
         10 . A nozzle, comprising:
 a. a shroud circumferentially surrounding the nozzle;   b. a plurality of barriers inside the shroud that extend radially across the nozzle, wherein the plurality of barriers define a fuel plenum and an air plenum, wherein the air plenum is downstream of the fuel plenum; and   c. a plurality of fuel channels radially outward of a centerline of the nozzle, wherein the plurality of fuel channels are defined as a fluid passage and include an inlet and an outlet downstream of the inlet, a fuel port in fluid communication with the fuel plenum and an air port in fluid communication with the air plenum, wherein the air port is downstream of the fuel port.   
     
     
         11 . The nozzle as in  claim 10 , wherein each of the plurality of fuel channels comprises a cylindrical passage that extends from the fuel plenum to an exit of the nozzle. 
     
     
         12 . The nozzle as in  claim 10 , wherein each of the plurality of fuel channels includes the fuel port. 
     
     
         13 . The nozzle as in  claim 10 , wherein each of the plurality of fuel channels includes the air port. 
     
     
         14 . The nozzle as in  claim 10 , wherein the fuel port is angled approximately 30 to approximately 90 degrees with respect to the axial centerline of the nozzle. 
     
     
         15 . The nozzle as in  claim 14 , wherein the air port is angled less than approximately 30 degrees with respect to the axial centerline of the nozzle. 
     
     
         16 . The nozzle as in  claim 10 , wherein the shroud includes at least one air port in fluid communication with the air plenum. 
     
     
         17 . A method for mixing fuel and air in a nozzle prior to combustion, comprising:
 a. flowing air through inlets of a plurality of fuel channels;   b. flowing fuel to a fuel plenum;   c. flowing air to an air plenum downstream of the fuel plenum;   d. injecting fuel from the fuel plenum through fuel ports in the plurality of fuel channels, wherein the plurality of fuel channels is radially outward of an axial centerline of the nozzle; and   e. injecting air from the air plenum through air ports in the plurality of fuel channels, wherein the air ports are downstream of the fuel ports.   
     
     
         18 . The method as in  claim 17 , further comprising injecting the fuel through the fuel ports at an angle between approximately 30 and approximately 90 degrees from the axial centerline of the nozzle. 
     
     
         19 . The method as in  claim 18 , further comprising injecting the air through the air ports at an angle less than approximately 30 degrees with respect to the axial centerline of the nozzle. 
     
     
         20 . The method as in  claim 17 , further comprising flowing air through air ports in a shroud peripherally surrounding the plurality of fuel channels.