METHOD AND APPARATUS WITH ARRANGEMENT OF FUEL EJECTION ORIFICES CONFIGURED FOR MITIGATING COMBUSTION DYNAMICS IN A COMBUSTION TURBINE ENGINE

1 - 21 . (canceled)

22 . Apparatus for a combustion turbine engine, comprising:

a pre-mixing passage having an upstream inlet arranged to receive a flow of air to be mixed with fuel;

a fuel-injecting lance disposed in the pre-mixing passage;

at least a first fuel ejection orifice disposed at a first axial location of the fuel-injecting lance;

at least a second ejection orifice disposed at a second axial location of the fuel-injecting lance, wherein a spacing between the first and second axial locations is arranged to effect oscillatory interference patterns in pockets comprising mixtures of air and fuel that flow towards a downstream outlet of the pre-mixing passage,

wherein the at least first fuel ejection orifice is part of a plurality of fuel ejection orifices disposed in a row at the first axial location and the at least second fuel ejection orifice is part of a plurality of fuel ejection orifices disposed in a row at the second axial location,

wherein the respective rows of fuel ejection orifices comprise circumferentially-extending rows of fuel ejection orifices respectively spanning at least respective portions of a perimeter of the fuel-injecting lance,

wherein the circumferentially-extending row of fuel ejection orifices at the first axial location comprises fuel ejection orifices configured for fuel-rich injection, and the circumferentially-extending row of fuel ejection orifices at the second axial location comprises fuel ejection orifices configured for fuel-lean injection.

23 . The apparatus of claim 22 , wherein the fuel ejection orifices at the first axial location are disposed over a first segment of the perimeter of the fuel-injecting lance, and the fuel ejection orifices at the second axial location are disposed over a second segment of the perimeter of the fuel-injecting lance, wherein the first segment and the second segment comprise circumferentially non-overlapping segments.

24 . The apparatus of 22 , wherein fuel ejection orifices at the first axial location are disposed over the perimeter of the fuel-injecting lance at a first set of circumferential locations, and the fuel ejection orifices at the second axial location are disposed over the perimeter of the fuel-injecting lance at a second set of circumferential locations, wherein the first set of circumferential locations are interspersed with the second set of circumferential locations to promote air/fuel mixing within the respective pockets.

25 . Apparatus for a combustion turbine engine, comprising:

a pre-mixing passage having an upstream inlet arranged to receive a flow of air to be mixed with fuel;

a fuel-injecting lance disposed in the pre-mixing passage;

at least a first fuel ejection orifice disposed at a first axial location of the fuel-injecting lance;

at least a second ejection orifice disposed at a second axial location of the fuel-injecting lance, wherein a spacing between the first and second axial locations is arranged to effect oscillatory interference patterns in pockets comprising mixtures of air and fuel that flow towards a downstream outlet of the pre-mixing passage,

wherein the at least first fuel ejection orifice is part of a plurality of fuel ejection orifices disposed in a row at the first axial location and the at least second fuel ejection orifice is part of a plurality of fuel ejection orifices disposed in a row at the second axial location,

wherein the respective rows of fuel ejection orifices comprise circumferentially-extending rows of fuel ejection orifices respectively spanning at least respective portions of a perimeter of the fuel-injecting lance, and

wherein 1) the circumferentially-extending row of fuel ejection orifices at the first axial location comprises fuel ejection orifices configured for fuel-rich injection, and the circumferentially-extending row of fuel ejection orifices at the second axial location comprises fuel ejection orifices configured for fuel-lean injection; or, wherein 2) the circumferentially-extending row of fuel ejection orifices at the first axial location comprises fuel ejection orifices configured for fuel-lean injection, and the circumferentially-extending row of fuel ejection orifices at the second axial location comprises fuel ejection orifices configured for fuel-rich injection.

26 . The apparatus of claim 25 , wherein the fuel ejection orifices at the first axial location are disposed over a first segment of the perimeter of the fuel-injecting lance, and the fuel ejection orifices at the second axial location are disposed over a second segment of the perimeter of the fuel-injecting lance, wherein the first segment and the second segment comprise circumferentially non-overlapping segments.

27 . The apparatus of claim 25 , wherein the fuel ejection orifices at the first axial location are disposed over the perimeter of the fuel-injecting lance at a first set of circumferential locations, and the fuel ejection orifices at the second axial location are disposed over the perimeter of the fuel-injecting lance at a second set of circumferential locations, wherein the first set of circumferential locations are interspersed with the second set of circumferential locations to promote air/fuel mixing within the respective pockets.

28 . The apparatus of claim 25 , wherein 1) the circumferentially-extending row of fuel ejection orifices at the first axial location in addition to the fuel ejection orifices configured for fuel-rich injection further comprises at least some fuel ejection orifices configured for fuel-lean injection, and the circumferentially-extending row of fuel ejection orifices at the second axial location in addition to the fuel ejection orifices configured for fuel-lean injection further comprises at least some fuel ejection orifices configured for fuel-rich injection; or wherein 2) the circumferentially-extending row of fuel ejection orifices at the first axial location in addition to the fuel ejection orifices configured for fuel-lean injection further comprises at least some fuel ejection orifices configured for fuel-rich injection, and the circumferentially-extending row of fuel ejection orifices at the second axial location in addition to the fuel ejection orifices configured for fuel-rich injection further comprises at least some fuel ejection orifices configured for fuel-lean injection.

29 . Apparatus for a combustion turbine engine, comprising:

a pre-mixing passage having an upstream inlet arranged to receive a flow of air to be mixed with fuel;

a fuel-injecting lance disposed in the pre-mixing passage;

an array of ejection orifices comprising a first group of ejection orifices axially arranged in the fuel-injecting lance relative to a second group of ejection orifices to effect oscillatory interference patterns in pockets comprising mixtures of air and fuel that flow towards a downstream outlet of the pre-mixing passage,

wherein the first group of ejection orifices comprises at least a first fuel ejection orifice disposed at a first axial location of the lance, and the second group of ejection orifices comprises at least a second ejection orifice disposed at a second axial location of the lance, wherein a spacing between the first and second axial locations is arranged to effect the oscillatory interference patterns,

wherein the at least first fuel ejection orifice is part of a plurality of fuel ejection orifices disposed in a row at the first axial location and the at least second fuel ejection orifice is part of a plurality of fuel ejection orifices disposed in a row at the second axial location,

wherein the respective rows of fuel ejection orifices comprise circumferentially-extending rows respectively spanning at least respective portions of a perimeter of the fuel-injecting lance,

wherein the circumferentially-extending row of fuel ejection orifices at the first axial location comprises fuel ejection orifices configured for fuel-lean injection, and the circumferentially-extending row of fuel ejection orifices at the second axial location comprises fuel ejection orifices configured for fuel-rich injection.

30 . The apparatus of claim 29 , wherein fuel ejection orifices at the first axial location are disposed over a first segment of the perimeter of the fuel-injecting lance, and the fuel ejection orifices at the second axial location are disposed over a second segment of the perimeter of the fuel-injecting lance, wherein the first segment and the second segment comprise circumferentially non-overlapping segments.

31 . The apparatus of claim 29 , wherein fuel ejection orifices at the first axial location are disposed over the perimeter of the fuel-injecting lance at a first set of circumferential locations, and the fuel ejection orifices at the second axial location are disposed over the perimeter of the fuel-injecting lance at a second set of circumferential locations, wherein the first set of circumferential locations are interspersed with the second set of circumferential locations to promote air/fuel mixing within the respective pockets.

32 . The apparatus of claim 29 , wherein the circumferentially-extending row of fuel ejection orifices at the first axial location comprises at least some fuel ejection orifices configured for fuel-rich injection, and the circumferentially-extending row of fuel ejection orifices at the second axial location comprises at least some fuel ejection orifices configured for fuel-lean injection.

33 . The apparatus of claim 29 , wherein a shape of the fuel ejection orifices is selected from the group consisting of circular shape, elongated shape, oval shape and a combination of two or more of circular, elongated and oval shapes.