Abstract: The burner assembly includes a flow body 12 having a central liquid fuel injection nozzle 14, inner and outer concentric passages 24 and 26, respectively, and a flow duct comprising a venturi downstream of the liquid injection nozzle. The inner passage 24 communicates air and gaseous fuel into the flow duct 16. Swirlers 30 and 38 are provided at the exit ends of the inner and outer passages, respectively, to create counterrotating flows which form a shear layer at the exit of the burner assembly body. The extent of the flow duct 16 facilitates liquid fuel atomization and vaporization, while affording sufficient time for gaseous fuel/air pre-mixing. The arrangement creates a recirculation zone 40 and a shear layer 42 at the exhaust of the burner assembly body which affords flame stabilization.

Abstract: An improved gas turbine combustor is provided which reduces nitric oxide emissions through premixing of the fuel gas and air and feeding the mixture through a venturi, providing an air cooled passage around the venturi, and extending the passage downstream toward the combustion zone to optimize the stability of the combustion and reduce NO.sub.x and CO emissions.

Abstract: A combustor includes inner and outer arrays of generally Vee-shaped, radially extending, circumferentially spaced gutters canted in a circumferential direction relative to one another to produce isolated concentric counter-rotating circumferentially directed flows downstream of the gutters. A lean premixed combustion mode is used at baseload operations. At non-baseload operations, particularly low-load operating conditions, a diffusion combustion mode is employed by direct fuel injection into air supplied to one of the isolated flow fields, preferably the radially inner flow field, to produce a stabilized, locally hotter flame, resulting in higher combustion efficiency and lower emissions than otherwise using a lean premixed combustion mode at the non-baseload operating conditions.

Abstract: A gas turbine combustor is provided with a premixer in which an oxidant and fuel is mixed and caused to flow to the combustion zone past two or more arrays of convex members positioned transverse or canted to the flow. The convex members introduce turbulence and include a plurality of openings to introduce one or more additional fuels into the premixed oxidant and fuel flow. Parallel, annular and radial arrays, or combinations thereof, may be provided. The downstream array is V-shaped in cross section and provides flame holding capability while the upstream array principally provides additional mixing of fuel and oxidant.

Abstract: An improved gas turbine combustor is provided which reduces nitric oxide emissions through premixing of the fuel gas and air and feeding the mixture through a venturi, providing an air cooled passage around the venturi, and extending the passage downstream toward the combustion zone to optimize the stability of the combustion and reduce NO.sub.x and CO emissions.

Abstract: It has been found that in a dry low NOx combustor of the type having an upstream combustion chamber and a downstream combustion chamber interconnected by a venturi section, the fuel-air ratio and uniform fuel-air mixing can be improved by providing an annular shield upstream of the venturi region. The shield is impingement cooled through the venturi and provision is made for dumping cooling air farther downsteam in the downstream combustion chamber. With the aforesaid improvements in mind, the upstream combustion chamber is provided with first and second inner liners which are also impringement cooled an which provide combustion air farther upstream into the upstream combustion chamber to further improve fuel-air mixing and to maintain the desired fuel-air ratio.

Abstract: A dual mode, dual stage low NOx combustor, includes a primary combustion chamber and a secondary combustion chamber separated by a throat region of reduced diameter. Fuel is input into the primary combustors by an annular array of diffusion type nozzles whereas in accordance with the invention fuel is input into the secondary combustor by a central combination premix and diffusion nozzle.