DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions
Applicant’s election without traverse of Species A (Figs. 4, 5) in the reply filed on 4/01/2026 is acknowledged.
Claims 12, 14, 15 have been withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 4/01/2026.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 1-11, 13, 16-18, 20 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Knoepfel (2007/0259296). Knoepfel teaches (1) A fuel injector for a gas turbine engine comprising a compressor section, combustion section, and turbine section is serial flow arrangement, the fuel injector comprising: an outer wall 4 defining a fuel injector axis and at least partially defining a mixing passage including a first mixing region 6 and a second mixing region [downstream 13] in serial arrangement; a first fuel passage 11 or 8 fluidly coupled to the mixing passage at the first mixing region 6 or 2; a first air passage 7 fluidly coupled to the mixing passage; and a second fuel passage 8 or 13 fluidly coupled to the mixing passage at the second mixing region [downstream 8 or 13]. (2) a second air passage [in 4, inclined passages in 4] fluidly coupled to the mixing passage. (3) wherein the second fuel passage 8 or 13 fluidly couples to the mixing passage aft of the second air passage [in 4, inclined passages in 4 adjacent 9]. (4) a centerbody 11 positioned within the outer wall and at least partially defining the mixing passage. (5) an interior within the centerbody 11. (6) a first centerbody passage fluidly coupling the interior to the mixing passage at the first mixing region 6. (7) a second centerbody passage positioned aft of the first centerbody passage. (8) wherein the second centerbody passage exhausts to the second mixing region [downstream 8]. (9) wherein the first fuel passage 11 or 8 is configured as a liquid fuel passage 11 and the second fuel passage 8 is configured as a gaseous fuel passage. (10) a set of turbulators 9 in annular arrangement extending from the outer wall 4 into the mixing passage. (11) wherein the set of turbulators 9 are positioned within the first mixing region 6 or 2. (13) A fuel injector for a turbine engine, the fuel injector comprising: an outer wall 4 in annular arrangement about a mixing passage, defining a fuel injector axis, and exhausting at an outlet, the mixing passage including a first mixing region 6 and a second mixing region [downstream 8 or 13] in serial arrangement, the first mixing region 6 or 2 having a first length and the second mixing region [downstream 8 or 13] having a second length, the first length longer than the second length; a first air passage 7 extending through the outer wall 4 to provide a supply of air to the mixing passage; a liquid fuel passage 11 or 13 fluidly coupled to the mixing passage at the first mixing region 6 or 2; and a gaseous fuel passage 8 fluidly coupled to the mixing passage at the second mixing region(16) a centerbody 11 positioned interior of the first air passage 7. (17) wherein the gaseous fuel passage 8 is offset from perpendicular to the outer wall 4 at an angle that is greater than or equal to negative seventy degrees (-70°) and less than or equal to seventy degrees (70°). (18) wherein a flow area is defined as a cross- sectional area of the mixing passage defined perpendicular to the fuel injector axis at an injector outlet, wherein a bluff body area is defined as the cross-sectional area for an aft face of the outer wall 4 defined perpendicular to the fuel injector axis, and wherein a ratio of flow area A1 to bluff body area [area of end of 4] is greater than or equal to 0.01 and less than or equal to 10 [appears to be so] (20) wherein the outlet for the mixing passage defines an outlet diameter, wherein the mixing passage defines a mixing length [from 6 to 3] defined in a direction along the fuel injector axis, and wherein a ratio of the mixing length to the outlet diameter [at A1] is greater than zero and less than or equal to 200 [appears to be so] .
PNG
media_image1.png
742
1226
media_image1.png
Greyscale
Claim(s) 1, 4-6, is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Cai et al (2013/0298562). Cai et al teach teaches (1) A fuel injector for a gas turbine engine comprising a compressor section, combustion section, and turbine section is serial flow arrangement, the fuel injector comprising: an outer wall 40 defining a fuel injector axis and at least partially defining a mixing passage 70 plus 72 to 42] including a first mixing region 70 and a second mixing region [portion of 68 downstream of 72 and 52] in serial arrangement [72 flows into 68]; a first fuel passage 56 fluidly coupled to the mixing passage at the first mixing region 70; a first air passage [either outer flow 68 or inner flow 64] fluidly coupled to the mixing passage; and a second fuel passage 60 fluidly coupled to the mixing passage at the second mixing region. (4) a centerbody 54 positioned within the outer wall 40 and at least partially defining the mixing passage. (5) an interior 70 within the centerbody. (6) a first centerbody passage 70 fluidly coupling the interior to the mixing passage 50 at the first mixing region.
Claim(s) 1-8, 10-11 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Sanders (2006/0021350). Sanders teaches (1) A fuel injector for a gas turbine engine comprising a compressor section, combustion section, and turbine section is serial flow arrangement, the fuel injector comprising: an outer wall 12 defining a fuel injector axis and at least partially defining a mixing passage including a first mixing region 21 and a second mixing region [downstream 37] in serial arrangement; a first fuel passage 36 fluidly coupled to the mixing passage at the first mixing region 21; a first air passage [24 or 25] fluidly coupled to the mixing passage; and a second fuel passage 16, 38 fluidly coupled to the mixing passage at the second mixing region [downstream 37]. (2) a second air passage 22 fluidly coupled to the mixing passage. (3) wherein the second fuel passage 16, 38 fluidly couples to the mixing passage aft of the second air passage 22. (4) a centerbody 19 positioned within the outer wall 12 and at least partially defining the mixing passage. (5) an interior 22 & 15 within the centerbody 19. (6) a first centerbody passage 15 fluidly coupling the interior to the mixing passage at the first mixing region 21. (7) a second centerbody passage [portion of 22 aft of 37] positioned aft of the first centerbody passage. (8) wherein the second centerbody passage 22 exhausts to the second mixing region [downstream 37]. (9) wherein the first fuel passage 36 is configured as a liquid fuel passage and the second fuel passage 16, 38 is configured as a fuel passage. (10) a set of turbulators 25 in annular arrangement extending from the outer wall 12 into the mixing passage. (11) wherein the set of turbulators 25 are positioned within the first mixing region 21.
Claim(s) 1-7, 9-11, 16-18, 20 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Bruhwiler et al (4967561). 1st interpretationBruhwiler et al teach (1) A fuel injector for a gas turbine engine comprising a compressor section, combustion section, and turbine section is serial flow arrangement, the fuel injector comprising: an outer wall 2 defining a fuel injector axis and at least partially defining a mixing passage including a first mixing region [downstream 15”] and a second mixing region [downstream 15’] in serial arrangement; a first fuel passage 15” fluidly coupled to the mixing passage at the first mixing region; a first air passage 14 fluidly coupled to the mixing passage; and a second fuel passage 15’ fluidly coupled to the mixing passage at the second mixing region. (2) a second air passage 30 fluidly coupled to the mixing passage. (3) wherein the second fuel passage 21, 15’ fluidly couples to the mixing passage aft of the second air passage 30. (4) a centerbody 4 positioned within the outer wall 2 and at least partially defining the mixing passage. (5) an interior within the centerbody 4. (6) a first centerbody passage 26 fluidly coupling the interior to the mixing passage at the first mixing region. (7) a second centerbody passage 12 positioned aft of the first centerbody passage. (10) a set of turbulators 28 in annular arrangement extending from the outer wall 2 into the mixing passage. (11) wherein the set of turbulators 28 are positioned within the first mixing region. (13) A fuel injector for a turbine engine, the fuel injector comprising: an outer wall 2 in annular arrangement about a mixing passage, defining a fuel injector axis, and exhausting at an outlet, the mixing passage including a first mixing region and a second mixing region in serial arrangement, the first mixing region having a first length [downstream of 15’] and the second mixing region [downstream of 15”] having a second length [between 15” to 15’], the first length longer than the second length; a first air passage 14 extending through the outer wall 2 to provide a supply of air to the mixing passage; a liquid fuel passage 15’ fluidly coupled to the mixing passage at the first mixing region; and a gaseous fuel passage 15” fluidly coupled to the mixing passage at the second mixing region. (16) a centerbody 4 positioned interior of the first air passage. (17) wherein the gaseous fuel passage 15” is offset from perpendicular to the outer wall 2 at an angle that is greater than or equal to negative seventy degrees (-70°) and less than or equal to seventy degrees (70°) [range includes zero, which is no offset from perpendicular]. (18) wherein a flow area is defined as a cross- sectional area of the mixing passage defined perpendicular to the fuel injector axis at an injector outlet, wherein a bluff body area is defined as the cross-sectional area for an aft face of the outer wall 2 defined perpendicular to the fuel injector axis, and wherein a ratio of flow area to bluff body area is greater than or equal to 0.01 and less than or equal to 10. (20) wherein the outlet for the mixing passage defines an outlet diameter, wherein the mixing passage defines a mixing length defined in a direction along the fuel injector axis, and wherein a ratio of the mixing length to the outlet diameter is greater than zero and less than or equal to 200. 2nd Interpretation
Bruhwiler et al teach (1) A fuel injector for a gas turbine engine comprising a compressor section, combustion section, and turbine section is serial flow arrangement, the fuel injector comprising: an outer wall defining a fuel injector axis and at least partially defining a mixing passage including a first mixing region [downstream 15’] and a second mixing region [downstream 15”] in serial arrangement; a first fuel passage 15’ fluidly coupled to the mixing passage at the first mixing region; a first air passage 26 fluidly coupled to the mixing passage; and a second fuel passage 15” fluidly coupled to the mixing passage at the second mixing region. (2) a second air passage 14 fluidly coupled to the mixing passage. (3) wherein the second fuel passage 15” fluidly couples to the mixing passage aft of the second air passage 14. (4) a centerbody 4 positioned within the outer wall and at least partially defining the mixing passage. (5) an interior 30, 12 within the centerbody 4. (6) a first centerbody passage 30 fluidly coupling the interior to the mixing passage at the first mixing region. (7) a second centerbody passage 12 positioned aft of the first centerbody passage. (9) wherein the first fuel passage 15’ is configured as a liquid fuel passage and the second fuel passage 15” is configured as a gaseous fuel passage. (10) a set of turbulators 26 in annular arrangement extending from the outer wall into the mixing passage. (11) wherein the set of turbulators 26 are positioned within the first mixing region. (13) A fuel injector for a turbine engine, the fuel injector comprising: an outer wall in annular arrangement about a mixing passage, defining a fuel injector axis, and exhausting at an outlet, the mixing passage including a first mixing region [downstream 15’] and a second mixing region [downstream 15”] in serial arrangement, the first mixing region [downstream 15’] having a first length and the second mixing region having a second length [between 15” and 15’], the first length longer than the second length; a first air passage 30 or 14 extending through the outer wall to provide a supply of air to the mixing passage; a liquid fuel passage 15’ fluidly coupled to the mixing passage at the first mixing region; and a gaseous fuel passage 15” fluidly coupled to the mixing passage at the second mixing region. (16) a centerbody 4 positioned interior of the first air passage. (17) wherein the gaseous fuel passage is offset from perpendicular to the outer wall at an angle that is greater than or equal to negative seventy degrees (-70°) and less than or equal to seventy degrees (70°) [includes zero]. (18) wherein a flow area is defined as a cross- sectional area of the mixing passage defined perpendicular to the fuel injector axis at an injector outlet, wherein a bluff body area is defined as the cross-sectional area for an aft face of the outer wall defined perpendicular to the fuel injector axis, and wherein a ratio of flow area to bluff body area is greater than or equal to 0.01 and less than or equal to 10. (20) wherein the outlet for the mixing passage defines an outlet diameter, wherein the mixing passage defines a mixing length defined in a direction along the fuel injector axis, and wherein a ratio of the mixing length to the outlet diameter is greater than zero and less than or equal to 200.
17. Claim(s) 1, 4-9, 13, 16-18, 20 is/are rejected under 35 U.S.C. 102(a)(1) as anticipated by Matt et al (445584). Matt et al teach (1) A fuel injector for a gas turbine engine comprising a compressor section 7, combustion section 2, and turbine section 10 is serial flow arrangement, the fuel injector comprising: an outer wall 25 defining a fuel injector axis and at least partially defining a mixing passage including a first mixing [downstream of 23 or 31] region and a second mixing region [downstream of 24] in serial arrangement; a first fuel passage 23 or 31 fluidly coupled to the mixing passage at the first mixing region; a first air passage 19 fluidly coupled to the mixing passage; and a second fuel passage 24 fluidly coupled to the mixing passage at the second mixing region. (4) a centerbody [e.g. 21, 22] positioned within the outer wall and at least partially defining the mixing passage. (5) an interior within the centerbody. (6) a first centerbody passage [upstream end of 14 in 21/22] fluidly coupling the interior to the mixing passage at the first mixing region. (7) a second centerbody passage [downstream of 14 of 21/22] positioned aft of the first centerbody passage. (8) wherein the second centerbody passage exhausts to the second mixing region [for 24]. (9) wherein the first fuel passage 31 is configured as a liquid fuel passage and the second fuel passage 24 is configured as a gaseous fuel passage. (13) A fuel injector for a turbine engine, the fuel injector comprising: an outer wall in annular arrangement about a mixing passage, defining a fuel injector axis, and exhausting at an outlet, the mixing passage including a first mixing region [downstream of 31] and a second mixing region [downstream of 24] in serial arrangement, the first mixing region having a first length and the second mixing region having a second length, the first length longer than the second length; a first air passage 19 extending through the outer wall to provide a supply of air to the mixing passage; a liquid fuel passage 31 fluidly coupled to the mixing passage at the first mixing region; and a gaseous fuel passage 24 fluidly coupled to the mixing passage at the second mixing region. (16) a centerbody 21/22 positioned interior of the first air passage. (17) wherein the gaseous fuel passage is offset from perpendicular to the outer wall at an angle that is greater than or equal to negative seventy degrees (-70°) and less than or equal to seventy degrees (70°). (18) wherein a flow area is defined as a cross- sectional area of the mixing passage defined perpendicular to the fuel injector axis at an injector outlet, wherein a bluff body area is defined as the cross-sectional area for an aft face of the outer wall defined perpendicular to the fuel injector axis, and wherein a ratio of flow area to bluff body area is greater than or equal to 0.01 and less than or equal to 10. (20) wherein the outlet for the mixing passage defines an outlet diameter, wherein the mixing passage defines a mixing length defined in a direction along the fuel injector axis, and wherein a ratio of the mixing length to the outlet diameter is greater than zero and less than or equal to 200.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1, 4-11, 13, 16-18, 20 is/are rejected under 35 U.S.C. 102(a)(1) as anticipated by Sloan (2647568) or, in the alternative, under 35 U.S.C. 103 as obvious over Sloan (2647568) in view of Blomeyer (2004/0055270). Sloan teaches (1) A fuel injector for a gas turbine engine comprising a compressor section, combustion section, and turbine section is serial flow arrangement [intended use], the fuel injector comprising: an outer wall 10 defining a fuel injector axis and at least partially defining a mixing passage including a first mixing region [downstream of 30] and a second mixing region [downstream of 15] in serial arrangement; a first fuel passage 30, 31 fluidly coupled to the mixing passage at the first mixing region; a first air passage [from 26] fluidly coupled to the mixing passage; and a second fuel passage 15, 14, 16 fluidly coupled to the mixing passage at the second mixing region. (4) a centerbody 33 positioned within the outer wall and at least partially defining the mixing passage. (5) an interior within the centerbody 33. (6) a first centerbody passage [slots in 33] fluidly coupling the interior to the mixing passage at the first mixing region. (7) a second centerbody passage [aft end of 33] positioned aft of the first centerbody passage. (8) wherein the second centerbody passage exhausts to the second mixing region. (9) wherein the first fuel passage 30 is configured as a liquid fuel passage and the second fuel passage 15 is configured as a gaseous fuel passage. (10) a set of turbulators [portions of 33, 43 between ribs 39 or ribs 39 themselves are the turbulators] in annular arrangement extending from the outer wall into the mixing passage. (11) wherein the set of turbulators [portions of 33, 43 between ribs 39 or ribs 39 themselves are the turbulators] are positioned within the first mixing region. (13) A fuel injector for a turbine engine [intended use], the fuel injector comprising: an outer wall in annular arrangement about a mixing passage, defining a fuel injector axis, and exhausting at an outlet, the mixing passage including a first mixing region [downstream of 30] and a second mixing region [downstream of 15] in serial arrangement, the first mixing region having a first length and the second mixing region having a second length, the first length longer than the second length; a first air passage 26 extending through the outer wall to provide a supply of air to the mixing passage; a liquid fuel passage 30, 31 fluidly coupled to the mixing passage at the first mixing region; and a gaseous fuel passage 15, 14, 16 fluidly coupled to the mixing passage at the second mixing region. (16) a centerbody 33 positioned interior of the first air passage. (17) wherein the gaseous fuel passage is offset from perpendicular to the outer wall at an angle that is greater than or equal to negative seventy degrees (-70°) and less than or equal to seventy degrees (70°) [includes zero, which is perpendicular]. (18) wherein a flow area is defined as a cross- sectional area of the mixing passage defined perpendicular to the fuel injector axis at an injector outlet, wherein a bluff body area is defined as the cross-sectional area for an aft face of the outer wall defined perpendicular to the fuel injector axis, and wherein a ratio of flow area to bluff body area is greater than or equal to 0.01 and less than or equal to 10. (20) wherein the outlet for the mixing passage defines an outlet diameter, wherein the mixing passage defines a mixing length defined in a direction along the fuel injector axis, and wherein a ratio of the mixing length to the outlet diameter is greater than zero and less than or equal to 200. As set forth above, the preamble may be treated as intended use and thus the claims anticipated. Sloan teaches the fuel injector is used in a furnace. Blomeyer teaches A fuel injector 1 for a gas turbine engine 110 [Fig. 4] comprising a compressor section 100, combustion section 102, and turbine section is serial flow arrangement 104 or more broadly for a turbine engine 110 is an equivalent application of the fuel injector to a furnace [¶ 0038]. It would have been obvious to one of ordinary skill in the art to utilize the fuel injector of Sloan for a gas turbine engine comprising a compressor section, combustion section, and turbine section is serial flow arrangement, as taught by Blomeyer, as an equivalent application to a furnace.
Claim(s) 1-9, 13, 16-18, 20 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Lee et al (6174160) or, in the alternative, under 35 U.S.C. 103 as obvious over Lee et al (6174160)) in view of Sloan (2647568). Lee et al teaches (1) A fuel injector for a gas turbine engine [col. 1, lines 20+] comprising a compressor section, combustion section, and turbine section is serial flow arrangement, the fuel injector comprising: an outer wall 24 defining a fuel injector axis and at least partially defining a mixing passage including a first mixing region 72 and a second mixing region 74 in serial arrangement; a first fuel passage 36 or 34 fluidly coupled to the mixing passage at the first mixing region; a first air passage 52 fluidly coupled to the mixing passage; and a second fuel passage [e.g. 76/78, see col. 9, lines 26-34 which teaches gaseous fuel is injected into second mixing region 74] fluidly coupled to the mixing passage at the second mixing region. (2) a second air passage 58 fluidly coupled to the mixing passage. (3) wherein the second fuel passage [e.g. leftmost 76/78, see col. 9, lines 26-34 which teaches gaseous fuel is injected into second mixing region 74] fluidly couples to the mixing passage aft of the second air passage 58. (4) a centerbody 48 positioned within the outer wall 24 and at least partially defining the mixing passage. (5) an interior within the centerbody 48. (6) a first centerbody passage 54 fluidly coupling the interior to the mixing passage at the first mixing region. (7) a second centerbody passage [within 50] positioned aft of the first centerbody passage. (8) wherein the second centerbody passage exhausts to the second mixing region 74. (9) wherein the first fuel passage 34 is configured as a liquid fuel passage and the second fuel passage 76/80 is configured as a gaseous fuel passage [see col. 9, lines 26-34 which teaches gaseous fuel is injected into second mixing region 74]. (13) A fuel injector for a turbine engine, the fuel injector comprising: an outer wall 24 in annular arrangement about a mixing passage, defining a fuel injector axis, and exhausting at an outlet 18, the mixing passage including a first mixing region [within 72] and a second mixing region 74 in serial arrangement, the first mixing region having a first length and the second mixing region [may be considered to have one end at 58] having a second length, the first length longer than the second length; a first air passage 16 extending through the outer wall 24 to provide a supply of air to the mixing passage; a liquid fuel passage 48 fluidly coupled to the mixing passage at the first mixing region; and a gaseous fuel passage 76/78 [see col. 9, lines 26-34 which teaches gaseous fuel is injected into second mixing region 74] fluidly coupled to the mixing passage at the second mixing region 74. (16) a centerbody 48 positioned interior of the first air passage. (17) wherein the gaseous fuel passage is offset from perpendicular to the outer wall 24 at an angle that is greater than or equal to negative seventy degrees (-70°) and less than or equal to seventy degrees (70°) [includes zero]. (18) wherein a flow area is defined as a cross- sectional area of the mixing passage defined perpendicular to the fuel injector axis at an injector outlet, wherein a bluff body area is defined as the cross-sectional area for an aft face of the outer wall 24 defined perpendicular to the fuel injector axis, and wherein a ratio of flow area to bluff body area is greater than or equal to 0.01 and less than or equal to 10. (19) wherein a fuel to air ratio as a ratio of the supply of fuel to the supply of air is greater than or equal to 0.005 and less than or equal to 0.060. (20) wherein the outlet for the mixing passage defines an outlet diameter, wherein the mixing passage defines a mixing length defined in a direction along the fuel injector axis, and wherein a ratio of the mixing length to the outlet diameter is greater than zero and less than or equal to 200. As set forth above, the second fuel passage / gaseous fuel passage was interpreted as being one of passages 76/88 as consistent with the teaching on col. 9, lines 26-34 which teaches gaseous fuel is injected into second mixing region 74. Alternately, Sloan teaches a second / gaseous fuel passage 15, 14, 16 fluidly coupled to the mixing passage at the second mixing region downstream of the first mixing zone. It would have been obvious to one of ordinary skill in the art to utilize the second / gaseous fuel passage fluidly coupled to the mixing passage at the second mixing region, as taught by Sloan, e.g. at left passage 76/78, as within the ordinary skill in the art as a typical injection location for the second/gas fuel into the second mixing region.
Claim(s) 1-8, 10-11, 13, 16-18, 20 as being unpatentable over Sanders (2006/0021350) in view of Naik et al (2023/0266009). Sanders teaches (9) wherein the first fuel passage 36 is configured as a liquid fuel passage and the second fuel passage 16, 38 is configured as a fuel passage. (13) A fuel injector for a turbine engine, the fuel injector comprising: an outer wall 12 in annular arrangement about a mixing passage, defining a fuel injector axis, and exhausting at an outlet, the mixing passage including a first mixing region 21 and a second mixing region [downstream 37] in serial arrangement, the first mixing region 21 having a first length and the second mixing region [downstream 37] having a second length, the first length longer than the second length; a first air passage [24 or 25] extending through the outer wall 12 to provide a supply of air to the mixing passage; a liquid fuel passage 36 fluidly coupled to the mixing passage at the first mixing region 21; and a fuel passage 16 fluidly coupled to the mixing passage at the second mixing region [downstream 37]. (16) a centerbody 19 positioned interior of the first air passage [24 or 25]. (17) wherein the fuel passage is offset from perpendicular to the outer wall 12 at an angle that is greater than or equal to negative seventy degrees (-70°) and less than or equal to seventy degrees (70°). (18) wherein a flow area is defined as a cross- sectional area of the mixing passage defined perpendicular to the fuel injector axis at an injector outlet, wherein a bluff body area is defined as the cross-sectional area for an aft face of the outer wall 12 defined perpendicular to the fuel injector axis, and wherein a ratio of flow area to bluff body area is greater than or equal to 0.01 and less than or equal to 10. (20) wherein the outlet for the mixing passage defines an outlet diameter, wherein the mixing passage defines a mixing length defined in a direction along the fuel injector axis, and wherein a ratio of the mixing length to the outlet diameter is greater than zero and less than or equal to 200.
Sanders teaches the claimed invention using a fuel passage for the second mixing region but do not teach (9) … the second fuel passage is configured as a gaseous fuel passage and (13) a gaseous fuel passage fluidly coupled to the mixing passage at the second mixing region (17) wherein the gaseous fuel passage is offset from perpendicular to the outer wall at an angle that is greater than or equal to negative seventy degrees (-70°) and less than or equal to seventy degrees (70°). Naik et al teach using a second / gas fuel passage 88 fluidly coupled to the mixing passage at the second mixing region [downstream 88]. It would have been obvious to one of ordinary skill in the art to employ a gaseous fuel passage fluidly coupled to the mixing passage at the second mixing region which is offset from perpendicular in the claimed ranged, as taught by Naik et al, as a typical type of fuel utilized in the art.
Claim(s) 1-11, 13 and 16-18, 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Naik et al (2023/0266009) in view of Boardman et al (10,890,329). Naik et al teach (1) A fuel injector for a gas turbine engine [Fig. 1] comprising a compressor section, combustion section, and turbine section is serial flow arrangement, the fuel injector comprising: an outer wall 71 defining a fuel injector axis and at least partially defining a mixing passage including a first mixing region 81 and a second mixing region [downstream 88] in serial arrangement; a first fuel passage 73A fluidly coupled to the mixing passage at the first mixing region 81; a first air passage 71A fluidly coupled to the mixing passage; and a second fuel passage 88 fluidly coupled to the mixing passage at the second mixing region [downstream 88]. (2) a second air passage 86 fluidly coupled to the mixing passage. (3) wherein the second fuel passage 88 fluidly couples to the mixing passage aft of the second air passage 86. (4) a centerbody 72 positioned within the outer wall 71 and at least partially defining the mixing passage. (5) an interior within the centerbody 72. (6) a first centerbody passage 86 fluidly coupling the interior to the mixing passage at the first mixing region 81. (7) a second centerbody passage 88 positioned aft of the first centerbody passage 86. (8) wherein the second centerbody passage 88 exhausts to the second mixing region [downstream 88]. (9) wherein the first fuel passage 73A is configured as a fuel passage and the second fuel passage 88 is configured as a gaseous fuel passage. (10) a set of turbulators [between passages 88 in Fig. 8] in annular arrangement extending from the outer wall 71 into the mixing passage. (11) wherein the set of turbulators are positioned within the first mixing region. (13) A fuel injector for a turbine engine, the fuel injector comprising: an outer wall 71 in annular arrangement about a mixing passage, defining a fuel injector axis, and exhausting at an outlet, the mixing passage including a first mixing region 81 and a second mixing region [downstream 88] in serial arrangement, the first mixing region 81 having a first length and the second mixing region [downstream 88] having a second length, the first length longer than the second length; a first air passage 71A extending through the outer wall 71 to provide a supply of air to the mixing passage; a fuel passage 73A fluidly coupled to the mixing passage at the first mixing region 81; and a gaseous fuel passage 88 fluidly coupled to the mixing passage at the second mixing region [downstream 88]. (16) a centerbody 72 positioned interior of the first air passage 71A. (17) wherein the gaseous fuel passage is offset from perpendicular to the outer wall 71 at an angle that is greater than or equal to negative seventy degrees (-70°) and less than or equal to seventy degrees (70°). (18) wherein a flow area is defined as a cross- sectional area of the mixing passage defined perpendicular to the fuel injector axis at an injector outlet, wherein a bluff body area is defined as the cross-sectional area for an aft face of the outer wall defined perpendicular to the fuel injector axis, and wherein a ratio of flow area to bluff body area is greater than or equal to 0.01 and less than or equal to 10. (19) wherein a fuel to air ratio as a ratio of the supply of fuel to the supply of air is greater than or equal to 0.005 and less than or equal to 0.060. (20) wherein the outlet for the mixing passage defines an outlet diameter, wherein the mixing passage defines a mixing length defined in a direction along the fuel injector axis, and wherein a ratio of the mixing length to the outlet diameter is greater than zero and less than or equal to 200. Naik et al teach the first fuel passage for the first mixing region may be a hydrocarbon but does not specifically teach it is a liquid [clm. 9, 13] but it appears to be at least hinted at, since in ¶ 0045 fuel is fluidly coupled to the combustion chamber and in ¶ 0030 “fluid” covers liquids. Alternately, Boardman et al teach (1) A fuel injector for a gas turbine engine [Fig. 1] comprising a compressor section, combustion section, and turbine section is serial flow arrangement, the fuel injector comprising: an outer wall 120 defining a fuel injector axis and at least partially defining a mixing passage including a first mixing region [downstream 131 or 132]; (9) wherein the first fuel passage 131 is configured as a liquid fuel passage. (13) … a liquid fuel passage fluidly coupled to the mixing passage at the first mixing region [downstream 131 or 132]. Boardman et al teach the fuel passages 131 in an analogous fuel injector may be either gaseous or liquid fuel [col. 7, lines 67-col. 8, line 8]. It would have been obvious to one of ordinary skill in the art to make the [first] fuel passage connected to the first mixing region a liquid fuel, as taught by Boardman et al, as a typical fuel utilized in that region of the fuel injector. Naik et al already teach the features of claims 10, 11, i.e. (11) a set of turbulators [between passages 88 in Fig. 8] in annular arrangement extending from the outer wall 71 into the mixing passage. (11) wherein the set of turbulators are positioned within the first mixing region. Alternately, Chyou teaches using (10) a set of turbulators 9, 9a in annular arrangement extending from the outer wall into the mixing passage. (11) wherein the set of turbulators 9, 9a are positioned within the first mixing region. The turbulators 9, 9a are positioned adjacent to or containing the fuel injection holes 22(a, b, c, …) in Figs. 8-14 to facilitate producing turbulence and vortices, with enhanced mixing and turbulence [col. 3, lines 1-48]. It would have been obvious to one of ordinary skill in the art to employ a set of turbulators in annular arrangement extending from the outer wall into the mixing passage; wherein the set of turbulators are positioned within the first mixing region, as positioned adjacent the second / gaseous fuel passage of Naik et al, in order to facilitate the mixing of the fuel and air in the mixing passage with enhanced turbulence and vortice generation.
Claim(s) 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over any of the prior art, as applied above, and further in view of either Robinson (4,222,232) or McWhirter et al (5,361,586). The prior art do not specifically teach (19) wherein a fuel to air ratio as a ratio of the supply of fuel to the supply of air is greater than or equal to 0.005 and less than or equal to 0.060. Robinson teaches (19) wherein a fuel to air ratio as a ratio of the supply of fuel to the supply of air is greater than or equal to 0.005 and less than or equal to 0.060 [¶ bridging cols. 4 and 5] is a typical range utilized in the art. or McWhirter et al teaches (19) wherein a fuel to air ratio as a ratio of the supply of fuel to the supply of air is greater than or equal to 0.005 and less than or equal to 0.060 [¶ bridging cols. 1 and 2]. It would have been obvious to one of ordinary skill in the art to employ a fuel to air ratio as a ratio of the supply of fuel to the supply of air is greater than or equal to 0.005 and less than or equal to 0.060, as taught by either Robinson or McWhirter et al, a typical range utilized in the art.
Claim(s) 18, 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over any of the prior art, as applied above, and further in view of the ordinary skill in the art. The applied prior art already appear to teach (18) wherein a flow area is defined as a cross- sectional area of the mixing passage defined perpendicular to the fuel injector axis at an injector outlet, wherein a bluff body area is defined as the cross-sectional area for an aft face of the outer wall defined perpendicular to the fuel injector axis, and wherein a ratio of flow area to bluff body area is greater than or equal to 0.01 and less than or equal to 10; (20) wherein the outlet for the mixing passage defines an outlet diameter, wherein the mixing passage defines a mixing length defined in a direction along the fuel injector axis, and wherein a ratio of the mixing length to the outlet diameter is greater than zero and less than or equal to 200. Alternately, these ranges are considered an obvious matter of using the workable ranges in the art. It would have been obvious to one of ordinary skill in the art to employ the claimed range of ratio of flow area to bluff body area is greater than or equal to 0.01 and less than or equal to 10 and a ratio of the mixing length to the outlet diameter is greater than zero and less than or equal to 200, as an obvious matter of using the workable ranges in the art.
Contact Information
Any inquiry concerning this communication or earlier communications from the Examiner should be directed to TED KIM whose telephone number is 571-272-4829. The Examiner can be reached on regular business hours before 5:00 pm, Monday to Thursday and every other Friday.
The fax number for the organization where this application is assigned is 571-273-8300.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Devon Kramer, can be reached at 571-272-7118. Alternate inquiries to Technology Center 3700 can be made via 571-272-3700.
Information regarding the status of an application may be obtained from Patent Center https://www.uspto.gov/patents/apply/patent-center. Should you have questions on Patent Center, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). General inquiries can also be directed to the Inventors Assistance Center whose telephone number is 800-786-9199. Furthermore, a variety of online resources are available at https://www.uspto.gov/patent
/Ted Kim/
Telephone
571-272-4829
Primary Examiner
Fax
571-273-8300
May 2, 2026
Prosecution Insights