CTNF 19/180,117 CTNF 90892 DETAILED ACTION 07-03-aia AIA 15-10-aia The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA. Claims 1-15 are currently pending in the application. Specification 07-29 AIA The disclosure is objected to because of the following informalities: The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed. The following title is suggested: FUEL SYSTEM FOR A GAS TURBINE ENGINE HAVING HYDROGEN FUEL OFFTAKE BURNER AND HEAT EXCHANGER Appropriate correction is required. Claim Objections 07-29-01 AIA Claim s 11-12 are objected to because of the following informalities: Claims 11 & 12 , each recite in line 1, “wherein the or each outlet” should be revised to: --wherein the at least one or each outlet--, for sake of consistency with how the limitation is recited in claim 1 (“ at least one outlet baffle ”); Appropriate correction is required. Claim Rejections - 35 USC § 112 07-30-02 AIA The following is a quotation of 35 U.S.C. 112(b): (b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention. The following is a quotation of 35 U.S.C. 112 (pre-AIA), second paragraph: The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention. 07-34-01 AIA Claim 11 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, or for pre-AIA the applicant regards as the invention. Claim 11, line 3, recites “ may be arranged to provide a pressure-drop of approximately 8 percent ”. This renders the claim indefinite, as the claim previously recited a pressure-drop range of “ between 1 percent and 15 percent ”. A broad range or limitation together with a narrow range or limitation that falls within the broad range or limitation (in the same claim) may be considered indefinite if the resulting claim does not clearly set forth the metes and bounds of the patent protection desired. See MPEP § 2173.05(c). The claim is considered indefinite because there is a question or doubt as to whether the feature introduced by such narrower language is (a) merely exemplary of the remainder of the claim, and therefore not required, or (b) a required feature of the claims. Claim Rejections - 35 USC § 103 07-20-aia AIA 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. 07-21-aia AIA Claim s 1, 5-9, 15 are rejected under 35 U.S.C. 103 as being unpatentable over Carrotte (US 2022/0099299 A1) in view of Zwick (US 4,138,842 A) . Regarding independent claim 1 , Carrotte discloses a fuel system 201 for a gas turbine engine (Fig. 2) comprising: a fuel offtake 501 (Fig. 5) configured to divert a portion of hydrogen fuel (from storage tank 104, Fig. 2, Para. 0055) from a main fuel conduit 502 (Para. 0077); a burner 504 configured to burn the portion of hydrogen fuel diverted from the main fuel conduit (Para. 0078, Fig. 5, “ Thus the vaporiser 303 vaporises the hydrogen fuel in the main fuel conduit 502 by combustion of the bled fuel in a burner 504 located in heat exchange relationship with the main fuel conduit 502 ”); a heat exchanger 303 (“ vaporizer ”, Fig. 3) configured to transfer heat from exhaust gasses produced by the burner to fuel in the main fuel conduit (Para. 0078-82, “ the products of combustion from the burner 504 are not mixed with the fuel in the main fuel conduit 502… there is enough heat emanating from the burner 504 to ensure vaporisation of the small amount of bled hydrogen fuel ”). Palmer fails to disclose at least one outlet baffle positioned between the burner and the heat exchanger configured to introduce turbulence to combustion gases entering the heat exchanger. Zwick teaches a fuel system (Fig. 3-4), having a burner 2 (Fig. 5, 6), and a heat exchanger 20 downstream the burner that heats a fuel flow (Col. 7, ln. 63-Col. 8, ln. 12), and at least one baffle 61 (deflector) positioned between the burner and the heat exchanger for introducing turbulence to the combustion gases that eventually enters the heat exchanger (Col. 9, ln. 41-62, “ The deflector 61 performs several functions. It promotes combustion turbulence by deflecting the combustion gases toward the wall 34 and also radiates heat to the combustion zone from its hot surfaces ”). Therefore it would have been obvious to one of ordinary skill in the art at the time the invention was filed to have incorporated into the system of Carrotte, at least one baffle between the burner and the heat exchanger (such as at an outlet side of the burner), as taught by Zwick, in order to promote combustion turbulence in the combustion gases to help ensure more complete burning of the fuel, while also directing the combustion gases towards the walls of the combustion zone to avoid creating a cold quench zone at the walls of the burner (Zwick Col. 9, ln. 41-62). Regarding claim 5 , Carrotte in view of Zwick teaches the fuel system according to claim 1, but fails to explicitly teach wherein the fuel system comprises an inlet baffle provided upstream in air flow of the burner. Zwick teaches an inlet baffle 46 (“ nose portion ” connected to burner body 32 guiding airflow into apertures 36 of the burner) provided upstream in air flow of the burner 2 (Fig. 5-7, the inlet baffle is upstream of the fuel manifold 48 of the burner, Col. 9, ln. 28-40). Therefore it would have been obvious to one of ordinary skill in the art at the time the invention was filed to have incorporated into the burner of Carrotte in view of Zwick, an inlet baffle upstream in air flow of the burner, as taught by Zwick, in order to provide a structure that can guide airflow into the burner (Col. 9, ln. 12-40). Regarding claim 6 , Carrotte in view of Zwick teaches the fuel system according to claim 1, and Carrotte further teaches wherein the fuel system comprises an auxiliary heater 506 (“ preheater ”, Fig. 5, Para. 0082) configured to heat hydrogen fuel in the fuel offtake, to heat hydrogen fuel prior to provision to the burner 504 (Para. 0082, “ the vaporiser 303 comprises a preheater 506 to ensure vaporisation of the bled hydrogen fuel prior to mixing with air in the premixer 505 ”). Regarding claim 7 , Carrotte in view of Zwick teaches the fuel system according to claim 1, but fails to teach wherein the fuel system comprises an electric ignitor configured to ignite hydrogen fuel within the burner. Zwick teaches a burner 2 having an electric ignitor 58 (“ spark plug ”, Col. 9, ln. 28-30). Therefore it would have been obvious to one of ordinary skill in the art at the time the invention was filed to have incorporated into the system of Carrotte in view of Zwick, an electric ignitor (such as a spark plug), in order to provide a known device for igniting the hydrogen fuel and air mixture within the burner. Use of electric ignitors is well-known in the art of burners/combustors. Regarding claim 8 , Carrotte in view of Zwick teaches the fuel system according to claim 6, and Carrotte further teaches swherein the fuel system comprises a hydrogen torch configured to ignite hydrogen fuel within the burner 504 (Para. 0078-82, implicit from the description of the burner, the burner receives hydrogen and air and consequently comprises a hydrogen “torch” that ignites the hydrogen from the offtake once the burner is started; see Fig. 5, the torch at the upstream end of the burner relative the offtake hydrogen flow). Regarding claim 9 , Carrotte in view of Zwick teaches the fuel system according to claim 8, and Carrotte further teaches wherein the hydrogen torch is provided downstream in fuel flow of the auxiliary heater 506 (Fig. 5, the hydrogen torch would be in the burner 504 which is downstream the auxiliary heater 506). Regarding claim 15, Carrotte in view of Zwick teaches the fuel system according to claim1, and Carrotte further teaches a gas turbine engine 103 (turbofan engine) comprising a fuel system according to claim 1 (Fig. 2, Para. 0090) . Allowable Subject Matter 12-151-08 AIA 07-43 12-51-08 Claim s 2-4, 10, 12-14 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. 07-43-02 AIA Claim 11 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims. Pertinent Prior Art 07-96 AIA The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Britton (US 3101593 A), Fetescu (US 6079222 A) teaches a gas turbine engine fuel system wherein a fuel supply includes an offtake diverting a portion of fuel to a burner to use combustion gas to heat the remainder of the fuel in the fuel line. Kutnjak (US 2017/0292450 A1) teaches a gas turbine engine having a heat exchanger using exhaust gas to preheat a fuel, the heat exchanger having an inlet baffle/valve arrangement. Palmer (US 20220099028 A1, US 11970975 B2), Carrotte (US 20220099025 A1, US 11828232 B2) teaches a fuel system similar to Carrotte cited in the rejection above. Contact Information Any inquiry concerning this communication or earlier communications from the examiner should be directed to ALAIN CHAU whose telephone number is (571)272-9444. The examiner can normally be reached on M-F 9am-6pm PST. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Devon Kramer can be reached on 571 272 7118. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /ALAIN CHAU/Primary Examiner, Art Unit 3741 Application/Control Number: 19/180,117 Page 2 Art Unit: 3741 Application/Control Number: 19/180,117 Page 3 Art Unit: 3741 Application/Control Number: 19/180,117 Page 4 Art Unit: 3741 Application/Control Number: 19/180,117 Page 5 Art Unit: 3741 Application/Control Number: 19/180,117 Page 6 Art Unit: 3741 Application/Control Number: 19/180,117 Page 7 Art Unit: 3741 Application/Control Number: 19/180,117 Page 8 Art Unit: 3741 Application/Control Number: 19/180,117 Page 9 Art Unit: 3741
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