Air flow conditioner for fuel injector of gas turbine engine

Abstract

A fuel injector for a gas turbine engine is provided. The fuel injector includes a central body, an air inlet duct, a mixing duct, a swirler, and a flow conditioner. The air inlet duct and the mixing duct are positioned around the central body to define an air flow passage. The swirler is positioned between the air inlet duct and the mixing duct. The flow conditioner is disposed in the air flow passage upstream with respect to the swirler. The flow conditioner has a perforated plate configured to uniformly distribute air circumferentially within the air inlet duct.

We claim: 
     
         1 . A fuel injector for a gas turbine engine, the fuel injector comprising:
 a central body;   an air inlet duct and a mixing duct positioned around the central body to define an air flow passage;   a swirler positioned between the air inlet duct and the mixing duct; and   a flow conditioner disposed in the air flow passage upstream with respect to the swirler, the flow conditioner having a perforated plate configured to uniformly distribute air circumferentially within the air inlet duct.   
     
     
         2 . The fuel injector of  claim 1 , wherein the flow conditioner comprises a cylindrical body to fit inside the air inlet duct and around the central body of the fuel injector. 
     
     
         3 . The fuel injector of  claim 2 , wherein the perforated plate is located at a downstream end of the cylindrical body. 
     
     
         4 . The fuel injector of  claim 2 , wherein the cylindrical body comprises an outer surface defining openings thereon. 
     
     
         5 . The fuel injector of  claim 1 , wherein the perforated plate comprises round perforations. 
     
     
         6 . The fuel injector of  claim 1 , wherein the perforated plate comprises curved rectangular perforations. 
     
     
         7 . The fuel injector of  claim 1 , wherein the swirler comprises a plurality of vanes that extend outward from the central body and into the air flow passage. 
     
     
         8 . The fuel injector of  claim 7 , wherein the vane comprises a plurality of fuel jets. 
     
     
         9 . The fuel injector of  claim 1 , wherein the central body comprises a pilot fuel injector configured to inject a pilot stream of fuel. 
     
     
         10 . A gas turbine engine comprising:
 a combustion chamber;   one or more fuel injectors comprising:
 a central body; 
 an air inlet duct and a mixing duct positioned around the central body to define an air flow passage; 
 a swirler positioned between the air inlet duct and the mixing duct; and 
 a flow conditioner disposed in the air flow passage upstream with respect to the swirler, the flow conditioner including a perforated plate configured to uniformly distribute air circumferentially within the air inlet duct. 
   
     
     
         11 . The gas turbine engine of  claim 10 , wherein the flow conditioner comprises a cylindrical body to fit inside the air inlet duct and around the central body of the fuel injector. 
     
     
         12 . The gas turbine engine of  claim 11 , wherein the perforated plate is located at a downstream end of the cylindrical body. 
     
     
         13 . The gas turbine engine of  claim 11 , wherein the cylindrical body comprises an outer surface defining openings thereon. 
     
     
         14 . The gas turbine engine of  claim 10 , wherein the perforated plate comprises round perforations. 
     
     
         15 . The gas turbine engine of  claim 10 , wherein the perforated plate comprises curved rectangular perforations. 
     
     
         16 . The gas turbine engine of  claim 10 , wherein the swirler comprises a plurality of vanes that extend outward from the central body and into the air flow passage. 
     
     
         17 . The gas turbine engine of  claim 16 , wherein the vane comprises a plurality of fuel jets. 
     
     
         18 . The gas turbine engine of  claim 10 , wherein the central body comprises a pilot fuel injector configured to inject a pilot stream of fuel. 
     
     
         19 . A method of delivering air-fuel mixture into a combustor chamber of a gas turbine engine, the method comprising:
 receiving pilot fuel from pilot fuel injectors into a central body of the fuel injector;   receiving fuel from vanes on a swirler into a mixing duct of the fuel injector;   receiving air from an air inlet duct into the mixing duct; and   uniformly distributing the air circumferentially within an air inlet duct of the fuel injector by a perforated plate of a flow conditioner disposed upstream with respect to the swirler; and   mixing fuel with the distributed air in the mixing duct;   receiving air-fuel mixture from the mixing duct together with the pilot fuel from the central body at the combustion chamber.   
     
     
         20 . The method of  claim 19 , wherein uniformly distributing the air circumferentially within an air inlet duct further comprises passing the air through one of round and curved rectangular perforations of the perforated plate.