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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 4/9/2026 has been entered.
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) 1-8, 10-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kraemer et al (US 20080078160 as referenced in OA dated 1/10/2025) in view of Carrea et al (US 20050282097 as referenced in OA dated 1/10/2025) and Joshi et al (US 5680766).
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Annotated Figure 5 of Joshi
Regarding claim 1, Kraemer discloses a gas turbine engine (Figure 1; 100), comprising:
a compressor section (Figure 1; 102), combustion section (Figure 1; 104), and turbine section (Figure 1; 108) in serial flow arrangement, with the combustion section comprising:
a combustor liner (The liner partially forming Figure 1; 106) that at least partially defines a combustion chamber (Figure 1; 106); and
a gaseous fuel nozzle assembly (Figure 8 using Figure 13 and 14. Paragraph 0032, 0058), comprising:
a first fuel supply (The first supply which supplies Figure 14; 162 to 154) to supply a first mixture of gaseous fuel and air (Figure 14; 162, Paragraph 0032, 0058);
a second fuel supply (The first supply which supplies Figure 14; 160 to 156) to supply a second mixture of gaseous fuel and air that is different than the first mixture of gaseous fuel and air (Figure 14; 160, Paragraph 0032);
a first impingement tube (Figure 14; 154) fluidly coupled to the first fuel supply to emit the first mixture into the combustion chamber;
a second impingement tube (An instance of Figure 14; 156 to the right of 154) fluidly coupled to the second fuel supply to emit the second mixture into the combustion chamber; and
wherein the first impingement tube and second impingement tube are arranged in an impinging configuration (Figure 14 shows the first and second impingement tubes in an impinging configuration) to define an impinging zone (The zone where flows from the first and second impingement tubes impinge) to facilitate impinging and mixing of the first mixture emitted from the first impingement tube and the second mixture emitted from the second impingement tube with each other (Functional Language, the impingement zone facilitates impinging and mixing the first and second mixtures).
Kraemer does not disclose a rich fuel supply to supply a rich mixture of gaseous fuel and air;
a lean fuel supply to supply a lean mixture of gaseous fuel and air that is leaner than the rich mixture of gaseous fuel and air;
a rich impingement tube fluidly coupled to the rich fuel supply to emit the rich mixture into the combustion chamber;
a lean impingement tube fluidly coupled to the lean fuel supply to emit the lean mixture into the combustion chamber; and
wherein the rich impingement tube and lean impingement tube are arranged in an impinging configuration to define an impinging zone to facilitate impinging and mixing of the rich mixture emitted from the rich impingement tube and the lean mixture emitted from the lean impingement tube with each other,
the impinging zone disposed at least partially within a premixing chamber, wherein the premixing chamber is defined forward of the combustion chamber and has a converging configuration in a direction extending towards the combustion chamber.
However, Carrea teaches a gas turbine engine (Figure 4), comprising:
a compressor section (Figure 4; 1), combustion section (Figure 4; 2, 21), and turbine section (Figure 4; 3) in serial flow arrangement, with the combustion section comprising:
a combustion chamber (Figure 4; 2); and a fuel nozzle assembly (Figure 4; 21), comprising:
a rich fuel supply (The supply to Figure 16; 5. Paragraph 0042, 0059, 0060) to supply a rich mixture of fuel and air (Paragraph 0042, 0059, 0060);
a lean fuel supply (The supply to Figure 16; 7. Paragraph 0042, 0059, 0060) to supply a lean mixture of fuel and air (Paragraph 0042, 0059, 0060) that is leaner than the rich mixture of gaseous fuel and air;
a rich impingement tube (Figure 16; 5) fluidly coupled to the rich fuel supply to emit the rich mixture into the combustion chamber;
a lean impingement tube (Figure 16; 7) fluidly coupled to the lean fuel supply to emit the lean mixture into the combustion chamber,
wherein the rich impingement tube and lean impingement tube are arranged in an impinging configuration (Functional language, The impinging configuration of Figure 16; 11 of 7 and 11 of 5, Paragraph 0042, 0059, 0060) to define an impinging zone (Functional language, The impingement zone of Figure 16; 11 of 7 and 11 of 5, Paragraph 0042, 0059, 0060) to facilitate impinging and mixing of the rich mixture emitted from the rich impingement tube and the lean mixture emitted from the lean impingement tube with each other (Functional Language, the impingement zone facilitates impinging and mixing the rich and lean mixtures).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Kraemer to include a rich fuel supply to supply a rich mixture of gaseous fuel and air; a lean fuel supply to supply a lean mixture of gaseous fuel and air that is leaner than the rich mixture of gaseous fuel and air; a rich impingement tube fluidly coupled to the rich fuel supply to emit the rich mixture into the combustion chamber; a lean impingement tube fluidly coupled to the lean fuel supply to emit the lean mixture into the combustion chamber; wherein the rich impingement tube and lean impingement tube are arranged in an impinging configuration to define an impinging zone to facilitate impinging and mixing of the rich mixture emitted from the rich impingement tube and the lean mixture emitted from the lean impingement tube with each other as taught by and suggested by Carrea in order to achieve optimum combustion during full-load operation (Paragraph 0042, 0060, the modification makes the first tube a rich tube and the second tube a lean tube)
Kraemer in view of Carrea does not teach wherein the impinging zone disposed at least partially within a premixing chamber, wherein the premixing chamber is defined forward of the combustion chamber and has a converging configuration in a direction extending towards the combustion chamber.
However, Joshi teaches an impinging zone (Annotated Figure 5; labeled impingement zone) disposed at least partially within a premixing chamber (Figure 5; 40), wherein the premixing chamber is defined forward of a combustion chamber (Figure 1; 14) and has a converging configuration (The converging configuration of Figure 5; 40 which is the same as Figure 1; 40) in a direction (The direction to the right in Figure 1 and 5) extending towards the combustion chamber.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Kraemer in view of Carrea wherein the impinging zone disposed at least partially within a premixing chamber, wherein the premixing chamber is defined forward of the combustion chamber and has a converging configuration in a direction extending towards the combustion chamber as taught by and suggested by Joshi in order to reduce NOx (Column 1, lines 6-11, the modification adds a premixing chamber in the dome/bulkhead of the combustor which partially defines the impinging zone and has a converging configuration).
Regarding claim 2, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the gaseous fuel nozzle assembly includes a wall (Figure 13; 105) coupled with the combustion liner; and
wherein the first (In the combined invention, this is the rich impingement tube) impingement tube and the second (In the combined invention, this is the lean impingement tube) impingement tube extend through the wall.
Kraemer in view of Carrea does not teach wherein the premixing chamber is defined at least partially within the wall.
However, Joshi teaches a wall (Figure 1; 20) coupled with a combustion liner (Figure 1, 16, 18);
wherein the premixing chamber is defined at least partially within the wall.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Kraemer in view of Carrea wherein the premixing chamber is defined at least partially within the wall as taught by and suggested by Joshi in order to reduce NOx (Column 1, lines 6-11, this is the same modification as claim 1).
Regarding claim 3, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer does not disclose wherein the rich mixture has a first equivalence ratio that is equal to or greater than 4.
However, Carrea teaches wherein the rich mixture has a first equivalence ratio that is equal to or greater than 4 (Paragraph 0042 states the fuel rich mixture is has any rate of air/fuel ratio below 1 which includes 0.2. This rejection uses a 0.2 air/fuel ratio. Paragraph 009 states the reciprocal of the air/fuel ratio is the equivalence ratio. A 0.2 air/fuel ratio is a 5 equivalence ratio).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Kraemer wherein the rich mixture has a first equivalence ratio that is equal to or greater than 4 as taught by and suggested by Carrea in order to achieve optimum combustion during full-load operation (Paragraph 0042, 0060, this is the same modification as claim 1).
Regarding claim 4, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer does not disclose wherein the lean mixture has a second equivalence ratio that is equal to less than 0.4.
However, Carrea teaches wherein the lean mixture has a second equivalence ratio that is equal to less than 0.4 (Paragraph 0059 states the air/fuel ratio is greater than 3. This rejection uses a 4 air/fuel ratio. Paragraph 009 states the reciprocal of the air/fuel ratio is the equivalence ratio. A 4 air/fuel ratio is a 0.25 equivalence ratio).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Kraemer wherein the lean mixture has a second equivalence ratio that is equal to less than 0.4 as taught by and suggested by Carrea in order to achieve optimum combustion during full-load operation (Paragraph 0042, 0060, this is the same modification as claim 1)
Regarding claim 5, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the second (In the combined invention, this is the lean impingement tube) impingement tube is a first second (In the combined invention, this is the lean impingement tube) impingement tube (The instance of Figure 14; 156 to the right of 154), and wherein the gaseous fuel nozzle assembly includes a second second (In the combined invention, this is the lean impingement tube) impingement tube (An instance of Figure 14; 156 to the left of 154) fluidly coupled to the second (In the combined invention, this is the lean fuel supply) fuel supply to emit the second (In the combined invention, this is the second mixture) mixture into the combustion chamber.
Regarding claim 6, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the first (In the combined invention, this is the rich impingement tube) impingement tube is disposed at least partially radially between the first second (In the combined invention, this is the lean impingement tube) impingement tube and the second second (In the combined invention, this is the lean impingement tube) impingement tube (Figure 13 shows the first impingement tube between the first and second second impingement tubes).
Regarding claim 7, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the gaseous fuel nozzle assembly includes a plurality of additional second (In the combined invention, this is the lean impingement tube) impingement tubes (The other instances of Figure 13; 152) arranged with the second (In the combined invention, this is the lean impingement tube) impingement tube about the first (In the combined invention, this is the rich impingement tube) impingement tube.
Regarding claim 8, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the first (In the combined invention, this is the rich impingement tube) impingement tube has a greater hydraulic diameter (Figure 13; 154 has a greater hydraulic diameter than 152) than the second (In the combined invention, this is the lean impingement tube) impingement tube.
Regarding claim 10, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the gaseous fuel nozzle assembly comprises a set of impingement tubes (Figure 13; 152 and 154) including the first (In the combined invention, this is the rich impingement tube) impingement tube and
the second (In the combined invention, this is the lean impingement tube) impingement tube, the set of impingement tubes including a centerline (The dotted vertical line partially defining Figure 14; 172);
the first (In the combined invention, this is the rich impingement tube) impingement tube is disposed at a first angle (The first angle the first impingement tubes makes with the centerline) relative to the centerline;
the second (In the combined invention, this is the lean impingement tube) impingement tube is disposed at a second angle (Figure 14; 172) relative to the centerline;
the first angle is greater than or equal to 0 degrees and less than or equal to 70 degrees (The first angle is 0 degrees);
the second angle is greater than or equal to 0 degrees and less than or equal to 70 degrees (The second angle is greater than 0 degrees but less than 70 degrees); and
at least one of the first angle or the second angle is greater than 0 degrees.
Regarding claim 11, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein outputs of the first (In the combined invention, this is the rich impingement tube) impingement tube and the second (In the combined invention, this is the lean impingement tube) impingement tube are offset by a center-to-center (The center to center distance of between the first and second impingement tubes) distance greater than or equal to a diameter (The diameter of the first impingement tube) of the first (In the combined invention, this is the rich impingement tube) impingement tube and less than or equal to 20 times the diameter of the first (In the combined invention, this is the rich impingement tube) impingement tube (The center to center distance is greater than the diameter of the first impingement tube and less than 20 times the diameter of the first impingement tube).
Regarding claim 12, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein outputs of the first (In the combined invention, this is the rich impingement tube) impingement tube and the second (In the combined invention, this is the lean impingement tube) impingement tube are offset by a center-to-center (The center to center distance of between the first and second impingement tubes) distance greater than or equal to a diameter (The diameter of the second impingement tube) of the second (In the combined invention, this is the lean impingement tube) impingement tube and less than or equal to 20 times the diameter of the second (In the combined invention, this is the lean impingement tube) impingement tube (The center to center distance is greater than the diameter of the second impingement tube and less than 20 times the diameter of the second impingement tube).
Regarding claim 13, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the first (In the combined invention, this is the rich impingement tube) impingement tube is circumferentially offset from the second (In the combined invention, this is the lean impingement tube) impingement tube relative to a centerline (Figure 8; 107) of the combustion section (The first and second tubes are circumferentially offset).
Regarding claim 14, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the gaseous fuel nozzle assembly includes three additional second impingement tubes (The other three instances of Figure 13; 152) arranged with the first (In the combined invention, this is the rich impingement tube) impingement tube and the second (In the combined invention, this is the lean impingement tube) impingement tube in an X-shaped configuration (The impingement tubes have an X-shaped configuration as shown in Figure 13).
Regarding claim 15, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the gaseous fuel nozzle assembly includes a first set of impingement tubes (The first, second, and three additional second impingement tubes) including the first (In the combined invention, this is the rich impingement tube) impingement tube, the second (In the combined invention, this is the lean impingement tube) impingement tube, and the three additional second (In the combined invention, this is the additional lean impingement tubes) impingement tubes; and wherein the gaseous fuel nozzle assembly includes a plurality of additional sets of impingement tubes (The other additional sets of impingement tubes shown in Figure 13 and 14 which replace the pairs of Figure 8; 154 and 152) disposed in additional X-shaped configurations (Figure 13 shows additional X-shaped configurations).
Regarding claim 16, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the plurality of additional sets of impingement tubes includes a first additional set of impingement tubes (The pair of Figure 8; 154 and 152 to the right of 9 which is replaced by Figure 13 and 14) circumferentially offset from the first set of impingement tubes and a second additional set of impingement tubes (The pair of Figure 8; 154 and 152 below 9 which is replaced by Figure 13 and 14) radially offset from the first set of impingement tubes and the first additional set of impingement tubes.
Claim(s) 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kraemer in view of Carrea and Joshi as applied to claim 1 above, and further in view of Brightwell (US 20220205393 as referenced in OA dated 5/9/2025)
Regarding claim 17, Kraemer in view of Carrea and Joshi teaches the invention as claimed.
Kraemer further discloses wherein the gaseous fuel comprises hydrogen (Paragraph 0005, 0029).
Kraemer in view of Carrea and Joshi does not teach wherein the gaseous fuel comprises hydrogen without a diluent.
However, Brightwell teaches wherein a gaseous fuel (The 100% of hydrogen fuel of Paragraph 0105) comprises hydrogen without a diluent (The 100% of hydrogen fuel of Paragraph 0105).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Kraemer in view of Carrea and Joshi wherein the gaseous fuel comprises hydrogen without a diluent as taught by and suggested by Brightwell in order to provide nitrogen oxide emissions abatement (Paragraph 0105, The modification uses 100% hydrogen gas as fuel).
Response to Arguments
Applicant’s arguments with respect to claim(s) 1 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to EDWIN G KANG whose telephone number is (571)272-9814. The examiner can normally be reached Mon-Fri 8:00-5:00 PM EST.
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/EDWIN KANG/Primary Examiner, Art Unit 3741
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