Lean-fuel gas turbine engine

Abstract

Provided is a compact lean-fuel gas turbine engine which does not cause performance degradation of the engine or pressure loss in the exhaust system, which comprises a compressor ( 1 ) for compressing an operative gas (G 1 ) to generate a compressed gas (G 2 ), the operative gas (G 1 ) having a concentration of burnable component which is less than a flammability limit thereof, a catalytic combustor ( 2 ) for combusting the compressed gas (G 2 ) by a catalytic reaction with an aid of a catalyst accommodated therein to generate a combustion gas (G 3 ), a turbine ( 3 ) adapted to be driven by the combustion gas (G 3 ) supplied from the catalytic combustor ( 2 ), a regenerator ( 6 ) for heating the compressed gas (G 2 ) supplied from the compressor ( 1 ) to the catalytic combustor ( 2 ) by an exhaust gas (G 4 ) supplied from the turbine ( 3 ) through an exhaust gas passage ( 25 ) to the regenerator ( 6 ), a burner ( 7 ) for burning a gas (G 20 ) extracted from the compressor ( 1 ) with a fuel to generate a heating gas (G 5 ) and supplying the heating gas (G 5 ) into the exhaust gas passage ( 25 ) and a valve ( 8 ) for controlling an amount of the extracted gas (G 20 ) to be supplied to the burner ( 7 ).

1 . A lean-fuel gas turbine engine, comprising:
 a compressor for compressing an operative gas to generate a compressed gas, the operative gas having a concentration of burnable component which is less than a flammability limit thereof;   a catalytic combustor for combusting the compressed gas by a catalytic reaction with an aid of a catalyst accommodated therein to generate a combustion gas;   a turbine adapted to be driven by the combustion gas supplied from the catalytic combustor;   a regenerator for heating the compressed gas supplied from the compressor to the catalytic combustor by an exhaust gas supplied from the turbine through an exhaust gas passage to the regenerator;   a burner for burning a gas extracted from the compressor with a fuel to generate a heating gas and supplying the heating gas into the exhaust gas passage; and   a valve for controlling an amount of the extracted gas to be supplied to the burner.   
     
     
         2 . The lean-fuel gas turbine engine of  claim 1 , wherein the valve is adapted to continuously increase or decrease the amount of the extracted gas to be supplied to the heating burner. 
     
     
         3 . The lean-fuel gas turbine engine of  claim 1 , wherein the heating burner is activated in a start-up operation of the gas turbine engine. 
     
     
         4 . The lean-fuel gas turbine engine of  claim 3 , wherein the heating burner works in a condition where the gas turbine engine works under the non-rated operation of which a rotation number is less than that of a rated operation of the gas turbine engine. 
     
     
         5 . The lean-fuel gas turbine engine in any one of  claim 1 , wherein the heating burner works when a combustion failure occurs at the catalytic combustor.