DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claims 1-20 are currently pending in the application.
Specification
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:
METHODS FOR INERTING A FUEL LINE IN A HYDROGEN GAS TURBINE PROPULSION SYSTEM
Appropriate correction is required.
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.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1-3, 6, 8-12, 16-19 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Palmer (US 2023/0092811 A1, cited in the information disclosure statement).
Regarding independent claim 1, Palmer discloses a method comprising:
activating at least one heat exchanger 501 (“recuperator”, Fig. 5 & 6, Para. 0128), 302 (“vaporizer”, Fig. 3, 6), 303 (“heater”, Fig. 3 & 4, Para. 0112) operatively coupled to a fuel line 605,606 (the heat exchangers are upstream of the fuel line portion 605, 606 and would be activated during operation of the plant shown in Fig. 6, Para. 0128, the recuperator is active when the core gas turbine engine 105 is active; Para. 0117-118, 122-126, the vaporizer 302 and heater 303 can be activated to heat the hydrogen to an injection temperature during certain operating modes; note, the claim does not specify any particular other conditions during which this step is meant to occur, e.g. during or after an engine shutdown; since the heat exchangers are activated at some point during operation of the system 201 of Fig. 6, Palmer’s method reads on the limitation);
injecting hydrogen into the fuel line (from fuel tank 104, or from tank 612, Para. 0108-109, 0130-131, Para. 0134-135) to distribute heat from the at least one heat exchanger in the fuel line (the aforementioned heat exchangers heat the hydrogen fuel to a desired firing temperature of “between 250 kelvin[K] and around 300 kelvin, for example around 280 kelvin”, Para. 0116, and would in turn, distribute the heat through the rest of the fuel line as the heated fuel moves downstream to the core turbine engine; again, the claim does not specify specifically when this step is meant to occur);
in response to a temperature of the fuel line being greater than a liquification temperature of an inert gas (nitrogen gas N2 stored in a vessel 611, Fig. 6, Para. 0134-137; the nitrogen/inert gas is stored as and is delivered in the form of a gas, for instance, during shut-down operations, Para. 0179-192; the liquification temperature of nitrogen gas is -210°C or 63K, which at least a portion of the fuel line would be above during regular operation by virtue of carrying heated hydrogen fuel at 250-300K; furthermore the system 201 is designed and operated such that the inert gas/nitrogen is delivered through the fuel line in a gas form, necessitating at least a portion of the fuel line be at a temperature greater than a liquification temperature in order to function; note, the claim is not explicitly requiring a step of sensing a temperature of the fuel line by some sensing device, or some control device implementing the following steps based on a detected temperature; the temperature of the fuel line being above a liquification temperature can be merely a condition of the system through which the following steps are implemented due to some change in operating mode; note, the fuel line is being interpreted as only the sections 605, 606 in Palmer, as the claim does not explicitly define what the fuel line encompasses):
injecting the inert gas into the fuel line (during a shut-down procedure, particularly allowing for maintenance, Para. 0189, “The fuel lines 601-606 may be purged with inert gas from the first purge gas tank 611 by first (step 1201) opening the fifth vent valve 635 and control valves 622, 625, 626, 627, 628, and 629, while leaving the first control valve 621 and vent valves 631, 632, 633, and 634 closed”; the inert gas can also be injected during a start-up procedure, Para. 0157-160);
terminating injecting the hydrogen into the fuel line (Para. 0179, “From a state where the engine 103 is running under fuel power alone, for example after the above described start-up procedure, shutdown of the engine 103 begins by first cutting off the flow of fuel to the engine 103 by closing the first control valve 621 to stop the flow of liquid fuel from the fuel tank 104”); and
capturing the inert gas in the fuel line (Para. 0189-192, “Once a sufficiently low level of fuel is detected, for example with hydrogen sensor 642 (step 1203), the fifth vent valve 635 may be closed (step 1204) and the other vent valves 631, 632, 633, and 634 briefly opened and closed (step 1205) to allow any remaining fuel gas to be vented to atmosphere… The third control valve 623 is then closed to stop the flow of purge gas (step 1206). The fuel delivery system 201 will then be inert”; any inert gas within the fuel lines following this step would be “captured” within the fuel line to “inert” the line).
Regarding claim 2, Palmer discloses the method of claim 1, further including opening a valve 621 operatively coupled to the fuel line (at portion 601) to cause the hydrogen (from tank 104) to recirculate in the fuel line (Para. 0167-169, for instance during a starting procedure following a previous purge/shutdown procedure when fuel is being allowed back into the fuel lines after being previously stopped) to distribute the heat from the at least one heat exchanger 302,501 (Para. 0168, the fuel is heated in vaporizer 302 when the engine is cranked at startup, which would distribute the heat absorbed in the vaporizer through the rest of the fuel line 605, 606; Para. 00174-175, eventually after the engine has warmed up, the heat exchanger/recuperator 501 heats the fuel an distributes the heat through the rest of the fuel line). Note, the claim does not specify any particular mode or condition during which this step is meant to occur, e.g. during or after an engine shutdown, during operation of the engine, during startup, etc..
Regarding claim 3, Palmer discloses the method of claim 2, wherein the valve is a first valve 621, further including closing a second valve to capture the inert gas in the fuel line (any of the vent valves 631-635 can be construed as the “second valve”, which are closed after a purging process using the inert gas; Para. 0189-192, “Once a sufficiently low level of fuel is detected, for example with hydrogen sensor 642 (step 1203), the fifth vent valve 635 may be closed (step 1204) and the other vent valves 631, 632, 633, and 634 briefly opened and closed (step 1205) to allow any remaining fuel gas to be vented to atmosphere… The third control valve 623 is then closed to stop the flow of purge gas (step 1206). The fuel delivery system 201 will then be inert”; any inert gas within the fuel lines following this step would be “captured” within the fuel line to “inert” the line).
Regarding claim 6, Palmer discloses the method of claim1, further including:
determining whether the hydrogen is emptied from the fuel line (via a hydrogen sensor 642, Para. 0191); and
closing a valve 631, 632, 633, 634 (vent valves), 623 (control valve of the inert gas) to capture the inert gas in the fuel line after the hydrogen is emptied from the fuel line (Para. 0191-192).
Regarding claim 8, Palmer discloses the method of claim 1, wherein injecting the inert gas 611 into the fuel line and terminating injecting the hydrogen 104 into the fuel line causes the inert gas to move the hydrogen out of the fuel line in advance of capturing the inert gas in the fuel line (Para. 0189-192, the inert gas pushes the hydrogen fuel remaining in the fuel lines to be vented out past the vent valves 631, 632, 633, 634 before the vent valves are closed and the inert gas in the fuel lines is “captured”).
Regarding independent claim 9, Palmer discloses a method to shut down an engine, the method comprising:
causing fuel 104 (hydrogen) to distribute heat in a fuel line 605,606 (the fuel lines shown in Fig. 6; via “recuperator 501”, Fig. 5 & 6, Para. 0128, “vaporizer 302”, Fig. 3 & 6, “heater 303”, Fig. 3 & 4, Para. 0112, operatively coupled to the fuel line, Para. 0117-118, 122-126; the aforementioned heat exchangers heat the hydrogen fuel to a desired firing temperature of “between 250 kelvin[K] and around 300 kelvin, for example around 280 kelvin”, Para. 0116, and would in turn, distribute the heat through the rest of the fuel line as the heated fuel moves downstream to the core turbine engine);
in response to a temperature of the fuel line being greater than a liquification temperature of an inert gas (nitrogen gas N2 stored in a vessel 611, Fig. 6, Para. 0134-137; the nitrogen/inert gas is stored as and is delivered in the form of a gas, for instance, during shut-down operations, Para. 0179-192; the liquification temperature of nitrogen gas is -210°C or 63K, which the fuel line would be above during regular operation by virtue of carrying heated hydrogen fuel at 250-300K; furthermore the system 201 is designed and operated such that the inert gas/nitrogen is delivered through the fuel line in a gas form, necessitating at least a portion of the fuel line be at a temperature greater than a liquification temperature in order to function; note, the claim is not explicitly requiring a step of sensing a temperature of the fuel line by some sensing device, or some control device implementing the following steps based on a detected temperature; the temperature of the fuel line being above a liquification temperature can be merely a condition of the system through which the following steps are implemented due to some change in operating mode):
injecting the inert gas into the fuel line (during a shut-down procedure, particularly allowing for maintenance, Para. 0189, “The fuel lines 601-606 may be purged with inert gas from the first purge gas tank 611 by first (step 1201) opening the fifth vent valve 635 and control valves 622, 625, 626, 627, 628, and 629, while leaving the first control valve 621 and vent valves 631, 632, 633, and 634 closed”; the inert gas can also be injected during a start-up procedure, Para. 0157-160);
terminating injecting the fuel into the fuel line (Para. 0179, “From a state where the engine 103 is running under fuel power alone, for example after the above described start-up procedure, shutdown of the engine 103 begins by first cutting off the flow of fuel to the engine 103 by closing the first control valve 621 to stop the flow of liquid fuel from the fuel tank 104”); and
capturing the inert gas in the fuel line (Para. 0189-192, “Once a sufficiently low level of fuel is detected, for example with hydrogen sensor 642 (step 1203), the fifth vent valve 635 may be closed (step 1204) and the other vent valves 631, 632, 633, and 634 briefly opened and closed (step 1205) to allow any remaining fuel gas to be vented to atmosphere… The third control valve 623 is then closed to stop the flow of purge gas (step 1206). The fuel delivery system 201 will then be inert”; any inert gas within the fuel lines following this step would be “captured” within the fuel line to “inert” the line).
Regarding claim 10, Palmer discloses the method of claim 9, further including activating at least one heat exchanger 501 (“recuperator”, Fig. 5 & 6, Para. 0128), 302 (“vaporizer”, Fig. 3, 6), 303 (“heater”, Fig. 3 & 4, Para. 0112) operatively coupled to the fuel line to provide the heat (Para. 0117-118, 122-126).
Regarding claim 11, Palmer discloses the method of claim 9, wherein the heat is engine heat radiated by the engine (the recuperator 501 uses heat from the engine exhaust, hence heat radiated by the engine, Para. 0128).
Regarding claim 12, Palmer discloses the method of claim 9, further including recirculating the fuel in the fuel line to distribute the heat (Para. 0167-169, for instance during a starting procedure following a previous purge/shutdown procedure when fuel is being allowed back into the fuel lines via valve 621 after being previously stopped; Para. 0168, the fuel is heated in vaporizer 302 when the engine is cranked at startup, which would distribute the heat absorbed in the vaporizer through the rest of the fuel line; Para. 00174-175, eventually after the engine has warmed up, the heat exchanger/recuperator 501 heats the fuel an distributes the heat through the rest of the fuel line). Note, the claim does not specify any particular mode or condition during which this step is meant to occur, e.g. during or after an engine shutdown, during operation of the engine, during startup, etc..
Regarding claim 16, Palmer discloses the method of claim 9, wherein the fuel includes hydrogen (Para. 0107-109, “A fuel tank 104 is located in the fuselage 102 for storing hydrogen fuel”, Para. 0130).
Regarding claim 17, Palmer discloses a method comprising:
heating a fuel line 605,606 (the fuel lines shown in Fig. 6; via “recuperator 501”, Fig. 5 & 6, Para. 0128, “vaporizer 302”, Fig. 3 & 6, “heater 303”, Fig. 3 & 4, Para. 0112, operatively coupled to the fuel line, Para. 0117-118, 122-126; the aforementioned heat exchangers heat the hydrogen fuel to a desired firing temperature of “between 250 kelvin[K] and around 300 kelvin, for example around 280 kelvin”, Para. 0116, and would in turn, distribute the heat through the rest of the fuel line in portions 605, 606 of the line as the heated fuel moves downstream to the core turbine engine) in preparation for an engine shut down (at least some of the heat exchangers, such as the recuperator, would be operating to heat the fuel up until a shutdown of the core turbine engine);
injecting hydrogen into the fuel line (from fuel tank 104, or from tank 612, Para. 0108-109, 0130-131, Para. 0134-135; hydrogen would be injected into the fuel line during operation of the core turbine engine; note, the claim does not specify any particular other conditions during which this step is meant to occur, e.g. during or after an engine shutdown; since the heat exchangers are activated at some point during operation of the system 201 of Fig. 6, Palmer’s method reads on the limitation);
injecting inert gas (gaseous nitrogen from a tank 611) into the fuel line to move the hydrogen out of the fuel line (during a shut-down procedure, particularly allowing for maintenance, Para. 0189, “The fuel lines 601-606 may be purged with inert gas from the first purge gas tank 611 by first (step 1201) opening the fifth vent valve 635 and control valves 622, 625, 626, 627, 628, and 629, while leaving the first control valve 621 and vent valves 631, 632, 633, and 634 closed”; Para. 0189-192, the inert gas pushes the hydrogen fuel remaining in the fuel lines to be vented out past the vent valves 631, 632, 633, 634 before the vent valves are closed and the inert gas in the fuel lines is “captured”); and
capturing the inert gas in the fuel line after the hydrogen is moved out of the fuel line (Para. 0189-192, “Once a sufficiently low level of fuel is detected, for example with hydrogen sensor 642 (step 1203), the fifth vent valve 635 may be closed (step 1204) and the other vent valves 631, 632, 633, and 634 briefly opened and closed (step 1205) to allow any remaining fuel gas to be vented to atmosphere… The third control valve 623 is then closed to stop the flow of purge gas (step 1206). The fuel delivery system 201 will then be inert”; any inert gas within the fuel lines following this step would be “captured” within the fuel line to “inert” the line).
Regarding claim 18, Palmer discloses the method of claim 17, wherein the inert gas is injected into the fuel line in response to a temperature of the fuel line being greater than a liquification temperature of the inert gas (Para. 0134-137; the nitrogen/inert gas is stored as and is delivered in the form of a gas, for instance, during shut-down operations, Para. 0179-192; the liquification temperature of nitrogen gas is -210°C or 63K, which at least a portion of the fuel line would be above during regular operation by virtue of carrying heated hydrogen fuel at 250-300K; furthermore the system 201 is designed and operated such that the inert gas/nitrogen is delivered through the fuel line in a gas form, necessitating at least a portion of the fuel line be at a temperature greater than a liquification temperature in order to function; note, the claim is not explicitly requiring a step of sensing a temperature of the fuel line by some sensing device, or some control device implementing the following steps based on a detected temperature; the temperature of the fuel line being above a liquification temperature can be merely a condition of the system through which the following steps are implemented due to some change in operating mode).
Regarding claim l9, Palmer discloses the method of claim 17, further including opening a valve 621 operatively coupled to the fuel line (at portion 601) to cause the hydrogen (from tank 104) to recirculate in the fuel line (Para. 0167-169, for instance during a starting procedure following a previous purge/shutdown procedure when fuel is being allowed back into the fuel lines after being previously stopped) to distribute heat from at least one heat exchanger (Para. 0168, the fuel is heated in vaporizer 302 when the engine is cranked at startup, which would distribute the heat absorbed in the vaporizer through the rest of the fuel line; Para. 00174-175, eventually after the engine has warmed up, the heat exchanger/recuperator 501 heats the fuel an distributes the heat through the rest of the fuel line). Note, the claim does not specify any particular mode or condition during which this step is meant to occur, e.g. during or after an engine shutdown, during operation of the engine, during startup, etc..
Allowable Subject Matter
Claims 4-5, 7, 13-15, 20 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.
Pertinent Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Geisler (US 2743997 A, US 2876069 A) teaches a system and method for preventing freezing in a jet aircraft purge gas generator.
LaVallee (US 20200317359 A1) teaches an aircraft fuel tank inerting system.
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.
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/ALAIN CHAU/Primary Examiner, Art Unit 3741
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