Fuel nozzle

Abstract

A fuel nozzle apparatus includes: a fuel distributor including an annular distributor ring, an aft interior mounting surface; and a pilot supply tube; a venturi defining a splitter with a first bore, and axially spaced-apart forward and aft exterior mounting surfaces; and a swirler including second bore and a forward interior mounting surface. The pilot supply tube is received in the second bore, outer ends of the inner vanes are received in the first bore; and the forward and aft exterior mounting surfaces of the venturi are received in the forward and aft interior mounting surfaces, respectively.

What is claimed is: 
     
         1 . A fuel nozzle apparatus comprising:
 a fuel distributor comprising:   a fuel conduit;   an annular distributor ring including: an array of fuel outlets, a main fuel passage communicating with the fuel conduit and the fuel outlets, and an aft interior mounting surface; and   a pilot supply tube extending axially from an inner end of the fuel conduit, and including a pilot fuel passage;   a venturi, comprising:   an annular splitter including a cylindrical forward portion with a first bore;   an annular venturi wall surrounding the splitter, the venturi including a cylindrical forward portion defining axially spaced-apart forward and aft exterior mounting surfaces; and   a row of first vanes extending between the forward portions of the splitter and the venturi wall;   a swirler comprising:   a hub with upstream and downstream ends, a second bore at the upstream end, and a pilot fuel outlet at the downstream end;   a row of second vanes extending outward from the hub;   an annular rim surrounding the upstream end of the hub, defining an air flow passage between the rim and the hub, and a forward interior mounting surface; and   a radially-extending wall interconnecting the hub and the rim;   wherein:   the pilot supply tube is received in the second bore;   outer ends of the second vanes are received in the first bore of the splitter; and   the forward and aft exterior mounting surfaces of the venturi are received in the forward and aft interior mounting surfaces, respectively.   
     
     
         2 . The apparatus of  claim 1  wherein the swirler further comprises a generally annular forward portion disposed forward of the annular rim, the forward portion having a wall section forming a U-shaped slot, and wherein the radially-extending wall is disposed at an intersection of the forward portion and the rim and spans across the U-shaped slot. 
     
     
         3 . The apparatus of  claim 1  further comprising:
 a centerbody having an annular wall surrounding the distributor ring, the annular wall having upstream and downstream ends, and including an array of first openings passing through the annular wall near the upstream end, each of the first openings aligned with one of the fuel outlets. 
 
     
     
         4 . The apparatus of  claim 3  wherein the annular wall of the centerbody includes one or more circumferential rows of second openings passing through the annular wall near the downstream end. 
     
     
         5 . The apparatus of  claim 1  wherein the venturi wall includes a conical aft portion extending aft from the cylindrical forward portion, and an annular heat shield disposed at an aft end of the conical aft portion. 
     
     
         6 . The apparatus of  claim 5  wherein a radial wall is disposed at an aft end of the centerbody, the radial wall including one or more circumferential rows of holes that are oriented to direct cooling air to impinge on the heat shield. 
     
     
         7 . The apparatus of  claim 1  wherein at least one of the fuel distributor, the venturi, and the fuel swirler is of unitary construction. 
     
     
         8 . The apparatus of  claim 7  wherein the unitary construction is made by a rapid manufacturing process. 
     
     
         9 . The apparatus of  claim 1  wherein:
 the fuel distributor is of unitary construction; 
 the venturi is of unitary construction; 
 the swirler is of unitary construction; and 
 the fuel distributor, the venturi, and the fuel swirler are connected to each other by braze joints. 
 
     
     
         10 . A fuel nozzle apparatus comprising:
 an annular distributor ring including an internal main fuel passage in fluid communication with an array of fuel posts that define individual fuel outlets;   a centerbody having an annular outer wall surrounding the distributor ring, the annular wall having upstream and downstream ends, and including:
 an array of first openings passing through the annular wall near the upstream end, each of the first openings aligned with one of the fuel posts; and 
 one or more circumferential rows of second openings passing through the annular wall near the downstream end. 
   
     
     
         11 . The apparatus of  claim 10  wherein:
 the annular outer wall includes a generally cylindrical portion and a radial portion which is disposed at approximately a right angle to the cylindrical portion, at an aft end thereof; 
 an inner edge of the radial portion contacts an aft end of the distributor ring, such that an annular passage for air flow is defined between the outer wall and the distributor ring; and 
 the rows of second openings pass through the cylindrical portion of the outer wall. 
 
     
     
         12 . The apparatus of  claim 10  wherein 1 to 4 circumferential rows of second openings are provided. 
     
     
         13 . The apparatus of  claim 10  wherein each row includes 60 to 80 second openings. 
     
     
         14 . The apparatus of  claim 10  wherein each second opening has a diameter between 0.020 inches and 0.030 inches. 
     
     
         15 . The apparatus of  claim 10  wherein each second opening is shaped as a diffuser opening with a variable cross sectional area.