Gas turbine combustion chambers

Claim 1

A combustion chamber arrangement for a gas turbine engine having air commpressor means, (a) an upstream portion; (b) partitioning means extending longitudinally of the upstream portion and defining therein a first chamber and a second chamber, the first chamber forming a combustion chamber comprising (1) a primary combustion zone having primary air intake means, idling fuel injection means and ignition means, and (2) a secondary combustion zone having secondary air intake means, and the second chamber forming a combustion chamber of the premixed burning type comprising a conduit having supplementary fuel injection means in an inlet region thereof, and a flame stabilizer system in a region intermediate said inlet region and an outlet of the conduit; (c) means in the air compressor means for supplying a first flow of air to the first chamber to feed (1) the primary combustion zone with primary combustion air through the primary intake means and (2) the secondary combustion zone with secondary combustion air through the secondary air intake means, and for supplying a second flow of air to the inlet region of the conduit; (d) means for running the gas turbine engine at idling speed comprising means for supplying fuel to said idling fuel injection means for said primary combustion zone at an idling flow rate to form a substantially stoichiometric air and fuel mixture with the primary combustion air in the primary zone at said idling speed of the gas turbine engine; (e) supplementary means for running the gas turbine engine at maximum speed comprising mean for supplying fuel to said supplementary fuel injection means at a supplementary flow rate to form a premixed air and fuel mixture with the second flow of air in said intermediate region of said conduit, and means for igniting said premixed air and fuel mixture in said intermediate region; (f) a downstream portion forming a mixture chamber to receive first and second gas flows issuing from the first and second chambers, respectively; and (g) means for producing at least one constriction of at least one of said gas flows at its entry into the downstream portion in order to produce intermixing of the two gas flows in the mixture chamber.