Abstract: A pilot burner (150, 350) for a gas turbine engine delivers an inner non-swirling fuel-oxidant mixture surrounded by an outer swirling fuel-oxidant mixture, thereby providing enhanced mixing with no recirculation zone. At least one fluid-restricting inlet port (166, 366) provides an oxidant to an inner mixing passage (160, 360). The inner mixing passage (160, 360) includes a plurality of fuel outlets (168). An outer annular mixing passage (180) receives oxidant from an upstream port (181) surrounding the inner mixing passage and includes at least one swirler element (186, 386) and fuel outlets (188).

Abstract: Methods and apparatus for injecting reagent, such as an aqueous urea solution, into an exhaust stream in order to reduce emissions from an engine exhaust. The present teachings can use a whirl plate having a plurality of whirl slots surrounding an exit orifice of an injector, which produce a high velocity rotating flow in the whirl chamber. When the rotating flow of reagent is passed through the exit orifice into an exhaust stream, atomization occurs from a combination of centrifugal force and shearing of the reagent by air as it jets into the exhaust stream.

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 method and apparatus for assembling an exhaust treatment device such as a catalytic converter employs post calibration to achieve a desired bulk gap density of a support mat surrounding a substrate in the device housing. The mat is gauged under pressure to a thickness yielding the target bulk gap density and the pressure is saved for use in comprising the device housing against the mat after soft stuffing of the mat/substrate subassembly into the housing.