System and method to eliminate a hard rub and optimize a purge flow in a gas turbine

Abstract

A system and method to eliminate hard rub and optimize a purge flow in a gas turbine is provided. The gas turbine includes a stator configured to guide a flow of an incoming gas. The gas turbine also includes a rotor configured to expand the incoming gas and extract kinetic energy from the incoming gas. The gas turbine further includes a purge flow bled from a compressor and configured to reduce a temperature of a wheel space by limiting ingestion of the incoming gas. The gas turbine also includes an angel wing disposed between the rotor and the stator and configured to act as a sealing surface between the rotor and the stator. The gas turbine further includes a fan blade disposed on a surface of the angel wing at an axial position and configured to generate a recirculation zone of the purge flow, wherein the recirculation zone is reduces a volume of successive purge flows entering the wheel space.

1 . A gas turbine comprising:
 a stator configured to guide a flow of an incoming gas;   a rotor configured to expand the incoming gas and extract kinetic energy from the incoming gas;   a purge flow bled from a compressor and configured to reduce a temperature of a wheel space by limiting ingestion of the incoming gas;   an angel wing disposed between the rotor and the stator and configured to act as a sealing surface between the rotor and the stator; and   a fan blade disposed on a surface of the angel wing at an axial position and configured to generate a recirculation zone of the purge flow, wherein the recirculation zone reduces a volume of successive purge flows entering the wheel space.   
     
     
         2 . The gas turbine of  claim 1 , wherein the stator comprises a discourager disposed above the angel wing in an overlapping manner. 
     
     
         3 . The gas turbine of  claim 1 , wherein the fan blade is configured to eliminate a hard rub between the discourager and the angel wing. 
     
     
         4 . The gas turbine of  claim 1 , wherein the angel wing comprises a horizontal structure extending outwardly from the rotor. 
     
     
         5 . The gas turbine of  claim 1 , wherein the angel wing comprises a tip protruding vertically at an edge of the surface of the angel wing. 
     
     
         6 . The gas turbine of  claim 2 , wherein the discourager comprises a honeycomb structure disposed between the tip and the discourager. 
     
     
         7 . The gas turbine of  claim 1 , wherein the axial position comprises an inclination angle relative to an axis of the angel wing. 
     
     
         8 . The gas turbine of  claim 1 , wherein the incoming gas comprises a hot gas. 
     
     
         9 . The gas turbine of  claim 1 , wherein the fan blade comprises a height relative to the angel wing and adequate to generate the recirculation zone. 
     
     
         10 . The gas turbine of  claim 1 , wherein the surface comprises an outward annular surface. 
     
     
         11 . A method of providing a gas turbine comprising:
 providing a stator configured to guide a flow of an incoming gas;   providing a rotor configured to expand the incoming gas and extract kinetic energy from the incoming gas;   providing a purge flow bled from a compressor and configured to reduce a temperature of a wheel space by limiting ingestion of the incoming gas;   providing an angel wing disposed between the rotor and the stator and configured to act as a sealing surface between the rotor and the stator; and   providing a fan blade disposed on a surface of the angel wing at an axial position and configured to generate a recirculation zone of the purge flow, wherein the recirculation zone reduces a volume of successive purge flows entering the wheel space.   
     
     
         12 . The method of  claim 11 , further comprising disposing a discourager above the angel wing in an overlapping manner. 
     
     
         13 . The method of  claim 11 , wherein providing the angel wing comprises providing a horizontal structure extending outwardly from the rotor. 
     
     
         14 . The method of  claim 11 , wherein providing the angel wing comprises providing a tip protruding vertically at an edge of the surface of the angel wing. 
     
     
         15 . The method of  claim 12 , wherein disposing the discourager comprises providing a honeycomb structure disposed between the tip and the discourager. 
     
     
         16 . The method of  claim 11 , wherein providing the fan blade comprises providing the fan blade at a height relative to the angel wing and adequate to generate the recirculation zone. 
     
     
         17 . The method of  claim 11 , wherein providing the fan blade disposed on the surface comprises providing the fan blade on an outward annular surface. 
     
     
         18 . The method of  claim 11 , wherein providing a purge flow comprises providing a cooling gas.