Gas turbine engine and buffer system therefor

Abstract

The present disclosure relates generally to a buffer vent system for a gas turbine engine. A supply of auxiliary pressurized gas is supplied to the buffer vent system during engine start during a period of time when the compressor section of the gas turbine engine is not able to supply adequate pressurized air to the buffer vent system.

What is claimed: 
     
         1 . An air system for a gas turbine engine comprising:
 a buffer vent system;   one or more air lines coupled to the buffer vent system for supplying pressurized air to the buffer vent system; and   a supply of auxiliary pressurized gas, ancillary to a compressor section, and operatively coupled to the buffer vent system for supplying the auxiliary pressurized gas to the buffer vent system.   
     
     
         2 . The air system of  claim 1 , wherein the one or more air lines comprise a plurality of air lines. 
     
     
         3 . The air system of  claim 1 , wherein the supply of auxiliary pressurized gas is coupled to the one or more air lines. 
     
     
         4 . The air system of  claim 1 , further comprising a metering orifice disposed between the supply of auxiliary pressurized gas and the buffer vent system. 
     
     
         5 . The air system of  claim 1 , further comprising a check valve disposed between the supply of auxiliary pressurized gas and the buffer vent system. 
     
     
         6 . The air system of  claim 1 , wherein the auxiliary pressurized gas comprises air. 
     
     
         7 . The air system of  claim 1 , wherein the auxiliary pressurized gas comprises nitrogen. 
     
     
         8 . The air system of  claim 1 , wherein the supply of auxiliary pressurized gas comprises a starter valve. 
     
     
         9 . The air system of  claim 8 , wherein the starter valve receives pressurized gas from a component selected from the group consisting of: an auxiliary power unit, a ground cart, and an engine test stand. 
     
     
         10 . The air system of  claim 1 , further comprising a compressor section coupled to the one or more air lines for supplying pressurized air to the buffer vent system. 
     
     
         11 . A gas turbine engine comprising:
 a compressor section;   a buffer vent system;   one or more air lines coupled to the compressor section and the buffer vent system for supplying pressurized air from the compressor section to the buffer vent system; and   a supply of auxiliary pressurized gas operatively coupled to the buffer vent system for supplying the auxiliary pressurized gas to the buffer vent system.   
     
     
         12 . The gas turbine engine of  claim 11 , wherein the one or more air lines comprise a plurality of air lines. 
     
     
         13 . The gas turbine engine of  claim 11 , wherein the supply of auxiliary pressurized gas is coupled to the one or more air lines. 
     
     
         14 . The gas turbine engine of  claim 11 , further comprising a metering orifice disposed between the supply of auxiliary pressurized gas and the buffer vent system. 
     
     
         15 . The gas turbine engine of  claim 11 , further comprising a check valve disposed between the supply of auxiliary pressurized gas and the buffer vent system. 
     
     
         16 . The gas turbine engine of  claim 11 , wherein the auxiliary pressurized gas comprises air. 
     
     
         17 . The gas turbine engine of  claim 11 , wherein the auxiliary pressurized gas comprises nitrogen. 
     
     
         18 . The gas turbine engine of  claim 11 , wherein the supply of auxiliary pressurized gas comprises a starter valve. 
     
     
         19 . The gas turbine engine of  claim 18 , wherein the starter valve receives pressurized gas from a component selected from the group consisting of: an auxiliary power unit, a ground cart, and an engine test stand.