Abstract: A combustor (28) for a gas turbine engine is provided comprising a primary combustion chamber (30) for combusting a first fuel to form a combustion flow stream (50) and a transition piece (32) located downstream from the primary combustion chamber (30). The transition piece (32) comprises a plurality of injectors (66) located around a circumference of the transition piece (32) for injecting a second fuel into the combustion flow stream (50). The injectors (66) are effective to create a radial temperature profile (74) at an exit (58) of the transition piece (32) having a reduced coefficient of variation relative to a radial temperature profile (64) at an inlet (54) of the transition piece (32). Methods for controlling the temperature profile of a secondary injection are also provided.

Abstract: A gas turbine combustor (10) comprises a base plate (12) from which protrude a plurality of lips (36) that surround respective apertures (16) into which are positioned downstream ends (19) of main swirler assemblies (18). The apertures (16) are arranged about a centrally positioned pilot cone (22) that comprises an inner cone (23) and an outer cone (25), defining a space (31) there between. A number of laterally directed apertures (60) are disposed along the outer cone (25) so as to direct a flow of fluid toward a near portion (38) of each lip (36), thereby perturbing pockets of high fuel-to-air mixtures between the outer cone (25) and the near region (38). The provision of such laterally directed apertures (60) reduces or eliminates flashback between the outer cone (25) and the near region (38) through such action.

Abstract: A gas turbine combustor (10) comprises a base plate (12) from which protrude a plurality of lips (36) that surround respective apertures (16) into which are positioned downstream ends (19) of main swirler assemblies (18). The apertures (16) are arranged about a centrally positioned pilot cone (22) that comprises an inner cone (23) and an outer cone (25), defining a space (31) there between. A number of laterally directed apertures (60) are disposed along the outer cone (25) so as to direct a flow of fluid toward a near portion (38) of each lip (36), thereby perturbing pockets of high fuel-to-air mixtures between the outer cone (25) and the near region (38). The provision of such laterally directed apertures (60) reduces or eliminates flashback between the outer cone (25) and the near region (38) through such action.

Abstract: Embodiments of the invention relate to a combustor flow sleeve for a turbine engine. According to aspects of the invention, the flow sleeve can be attached to one of the components in the combustor head-end by a plurality of fasteners. In one embodiment, the flow sleeve can be attached directly to the combustor head-end component by a plurality of bolts. The bolted flow sleeve can reduce the time to install or remove the flow sleeve. In certain areas, it may not be possible to directly attach the flow sleeve to the combustor component. A flow sleeve according to aspects of the invention can be adapted to facilitate indirect attachment to the combustor head-end component. The flow sleeve can further be adapted to include thermal relief slots to accommodate any differential thermal expansion or contraction between the flow sleeve and the component to which the flow sleeve is attached.

Abstract: A fuel/air mixing apparatus, such as a main swirler assembly (400) comprising a sleeve (410), provides for additional air entry around the perimeter of a bore (440) through which passes a fuel/air mixture. The additional air reduces or eliminates flashback during operation of a gas turbine comprising the assembly (400). In some embodiments, a plurality of gaps (464) exists between spaced apart tabs (462) along a downstream end (460) of the sleeve (410). During gas turbine operation, air flows through both a flashback annulus (411) and the gaps (464). In other embodiments, a plurality of holes are placed upstream and in line with the tabs (1004) to supplement the air flow through gaps (1006). In yet other embodiments, rows (1102) of holes (1104) are provided to supplement the airflow. Downstream ends (460,1218) may interface with a downstream-oriented lip (460) or with an upstream-oriented lip (1224). The interfacing may comprise a fit effective to damp vibration and to increase the natural frequency.

Abstract: In one embodiment, a combustor (28) for a gas turbine engine is provided comprising a primary combustion chamber (30) for combusting a first fuel to form a combustion flow stream (50) and a transition piece (32) located downstream from the primary combustion chamber (30). The transition piece (32) comprises a plurality of injectors (66) located around a circumference of the transition piece (32) for injecting a second fuel into the combustion flow stream (50). The injectors (66) are effective to create a radial temperature profile (74) at an exit (58) of the transition piece (32) having a reduced coefficient of variation relative to a radial temperature profile (64) at an inlet (54) of the transition piece (32). Methods for controlling the temperature profile of a secondary injection are also provided.

Abstract: A secondary fuel delivery system for delivering a secondary stream of fuel and/or diluent to a secondary combustion zone located in the transition piece of a combustion engine, downstream of the engine primary combustion region is disclosed. The system includes a manifold formed integral to, and surrounding a portion of, the transition piece, a manifold inlet port, and a collection of injection nozzles. A flowsleeve augments fuel/diluent flow velocity and improves the system cooling effectiveness. Passive cooling elements, including effusion cooling holes located within the transition boundary and thermal-stress-dissipating gaps that resist thermal stress accumulation, provide supplemental heat dissipation in key areas.

Abstract: A combustor (40) for a gas turbine engine is provided with a premix pilot fuel stage (42) in order to reduce the emission of oxides of nitrogen from the engine. An in-service engine may be modified to add the premix pilot fuel stage by delivering premix pilot fuel to a ring manifold (42) for tip-feeding a premix pilot fuel outlet member such as a swirler vane (78) or fuel peg (124). In this manner, complex and expensive components such as the top hat (46), support housing (48) and diffusion pilot burner assembly (44) may be used without modification. Thermal stresses caused by the differential cooling of the ring manifold by the premix pilot fuel (96) are reduced by a heat shield (94) installed within the manifold.