Multiple stage gas turbine engine

Abstract

A gas turbine engine ( 34 ) including a compressor ( 36 ) for producing compressed air, a first stage of combustion ( 24 ) in the compressed air producing combustion gas, an expansion turbine ( 61 ) expanding the combustion gas to produce work and an exhaust gas ( 14 ), a second stage of combustion ( 26 ) in the combustion gas disposed downstream of a first stage of expansion in the turbine ( 61 ), and a third stage of combustion ( 28 ) in the combustion gas disposed downstream of the second stage ( 26 ) of combustion. None of the stages of combustion produce a temperature in the combustion gas of more than about 1,400° C.

1 . A gas turbine engine comprising:
 a compressor for producing compressed air;   a first stage of combustion in the compressed air producing combustion gas;   an expansion turbine expanding the combustion gas to produce work and an exhaust gas;   a second stage of combustion in the combustion gas disposed downstream of a first stage of expansion in the turbine; and   a third stage of combustion in the combustion gas disposed downstream of the second stage of combustion,   wherein none of the stages of combustion produce a temperature in the combustion gas of more than about 1,400° C.   
     
     
         2 . The gas turbine engine of  claim 1 , wherein at least one of the stages of combustion comprises a torus-configured combustion chamber that is associated with a vane of the expansion turbine. 
     
     
         3 . The gas turbine engine of  claim 1 , wherein the first stage of combustion and the third stage of combustion each comprise a torus-configured combustion chamber that is associated with a respective stage vane of the expansion turbine. 
     
     
         4 . The gas turbine engine of  claim 1 , wherein each of the stages of combustion comprises a torus-configured combustion chamber that is associated with a respective vane of the expansion turbine. 
     
     
         5 . The gas turbine engine of  claim 1 , wherein the first stage of combustion comprises a torus-configured combustion chamber that is associated with a first stage vane of the expansion turbine, and the second and third stages of combustion each comprise in-situ reheat combustion associated with the respective second and third stages of the expansion turbine. 
     
     
         6 . The gas turbine engine of  claim 1 , wherein the first stage of combustion comprises a torus-configured combustion chamber that is associated with a first stage vane of the expansion turbine, the second stage of combustion comprises in-situ reheat combustion associated with the second stage of the expansion turbine, and the third stage of combustion comprises a torus-configured combustion chamber that is associated with a third stage of the expansion turbine. 
     
     
         7 . The gas turbine engine of  claim 1 , wherein the compressor comprises an aspirated compressor. 
     
     
         8 . The gas turbine engine of  claim 1 , wherein the compressor, stages of combustion, and expansion turbine are synergistically effective to provide the exhaust gas at a temperature of about 640° C. with no more than about 3 ppm of NOx.