초록 ▼

A generally annular combustor system has a combustion chamber with an annular chamber portion and a plurality of can-like chamber portions protruding tangentially from the annular chamber portion, the portions collectively defining a single stage combustor. An external fuel/air premixer is associate

A generally annular combustor system has a combustion chamber with an annular chamber portion and a plurality of can-like chamber portions protruding tangentially from the annular chamber portion, the portions collectively defining a single stage combustor. An external fuel/air premixer is associated with each can chamber portion to provide a preselected, nominally constant, lean fuel/air ratio mixture. A portion of the total compressed air flows to the premixers and the remaining portion is ducted to convection cooling passageways and finally admitted as dilution air proximate the exit of the annular chamber portion. When the fuel/power setting is changed, the combustion air flow is automatically set by varying the position of air valves associated with each premixer to achieve the desired combustible mass flow. In one embodiment, the air valve controls the dilution air flow rate from the plenum region and thus, indirectly, the combustion air flow rate. In an alternative embodiment, the air valve controls the combustion air to the premixers directly. Each premixer includes a venturi and a fuel nozzle for spraying liquid fuel or gas into the venturi inlet along the venturi axis to provide the fully premixed fuel/air mixture. The annular chamber portion advantageously can be nested between the compressor and turbine components of large axial-type flow gas turbines.

대표청구항 ▼

A combustor system for operation with a source of compressed air and a source of fuel in a gas turbine, the combustor system comprising: a combustion chamber; and at least one premixer located externally of said combustion chamber for premixing fuel and a first portion of the compressed air from the

A combustor system for operation with a source of compressed air and a source of fuel in a gas turbine, the combustor system comprising: a combustion chamber; and at least one premixer located externally of said combustion chamber for premixing fuel and a first portion of the compressed air from the respective sources for delivery of a fuel/air mixture to the combustion chamber, the premixer further comprising: a venturi having an inlet and an axis, said venturi inlet being operatively connected to said source of compressed air to define a compressed air flow path into said venturi inlet, the portion of the flow-path immediately upstream of said inlet comprising an inlet region, said venturi also having an outlet flow-connected to said combustion chamber, the flow area of said venturi outlet being selected to provide minimum outlet velocities greater than the flame propagation speed of the fuel/air mixture; and a fuel nozzle operatively connected to the fuel source and having an exit positioned to deliver a spray of fuel into said venturi inlet region, wherein said first compressed air portion constitutes essentially all of the compressed air that undergoes combustion with the fuel in said combustion chamber, and wherein said combustion chamber is cooled by another portion of the compressed air by convection cooling without film cooling.