JP5832340B2 - Fuel supply system, scramjet engine and method of operating the same - Google Patents

Description

  The present invention relates to a scramjet engine that generates thrust by performing supersonic combustion, and more particularly to a fuel supply system for a scramjet engine.

  In order to stabilize supersonic combustion using a hydrocarbon-based fuel, it is desirable to increase the proportion of the low carbon number component contained in the fuel and to make the fuel composition constant. On the other hand, low-carbon hydrocarbons are in a gaseous state at room temperature, so if low-carbon hydrocarbons are installed in fuel tanks, the amount of fuel loaded cannot be increased, and supersonic combustion (super (Sonic Flight) cannot be performed. For this reason, jet fuel that contains hydrocarbons with high carbon numbers and is liquid at room temperature can be mounted in a fuel tank, and the jet fuel can be decomposed by the heat of the engine during flight to produce hydrocarbons with low carbon numbers. It is considered.

  Patent Document 1 discloses a thermal management system for a propulsion engine of a supersonic and hypersonic aircraft. The system uses a single flow of endothermic fluid as engine fuel and as a heat sink for engine cooling. The system includes a plurality of heat exchangers arranged in series. Each heat exchanger is provided with a reaction part provided with a catalyst so as to have a heat exchange relationship with the heat source part. The single fluid flow flows through each of the reaction section and the heat source section. Heat for reaction in the reaction section is provided by the fluid in the heat source section, and as a result, the fluid is cooled. This cooled fluid is reheated when it flows through the high temperature part of the engine, and then flows to another reaction part, or flows to the combustor of the engine and is ignited.

  Patent Document 2 discloses a method of increasing a combustion speed and extending a misfire limit in a high speed propulsion unit such as a ramjet and a scramjet engine. Hydrocarbon fuel streams are catalytically cracked to produce hydrogen and low molecular weight fuel cracked products. The hydrogen and low molecular weight fuel decomposition products are introduced into the combustor of the high speed propulsion unit along with the flow of undecomposed hydrocarbon fuel. This method extends the operating range of the combustor and achieves higher combustion rates and increased flame stability through faster diffusion mixing. The process effectively extends the operational limits of gas turbines, particularly ramjet and scramjet combustors.

  Patent Document 2 further discloses the following contents. The fuel is vaporized in a catalytic reactor and is catalytically decomposed into hydrogen and low molecular weight fuel decomposition products. What fuel breakdown is produced depends on what fuel is sent to the reactor. Preferred catalysts used in the reactor include platinum group metals such as platinum, rhodium, iridium, palladium. Catalysts containing other metals such as nickel, chromium, cobalt have also been shown to be effective. The catalyst may be composed of a single metal or a combination of suitable metals.

  Non-Patent Document 1 discloses the relationship between the minimum ignition energy and the equivalence ratio for methane, ethane, propane, butane, hexane, and heptane. For all of methane, ethane, propane, butane, hexane, and heptane, the minimum value of the minimum ignition energy is around 0.25 mJ. Methane has a lower equivalence ratio for obtaining the minimum value of minimum ignition energy than ethane, propane, butane, hexane, and heptane.

US Pat. No. 5,337,553 US Pat. No. 5,394,685

Takashi Niioka, Nobukata Kono, Jun-ichi Sato, "Fundamentals of Combustion Phenomenon", published on August 25, 2001, Fig. 4.3

  An object of the present invention is to maintain a constant composition of the reformed fuel in a scramjet engine that pyrolyzes fuel with heat from the combustion chamber to generate reformed fuel and burns the reformed fuel in the combustion chamber, and Another object of the present invention is to provide a fuel supply system, a scramjet engine, and an operation method thereof capable of separately controlling the cooling capacity of the combustion chamber by the thermal decomposition of the fuel and the generation amount of the reformed fuel.

  The means for solving the problem will be described below using the numbers used in the (DETAILED DESCRIPTION). These numbers are added to clarify the correspondence between the description of (Claims) and (Mode for Carrying Out the Invention). However, these numbers should not be used to interpret the technical scope of the invention described in (Claims).

  The fuel supply system (15) according to the first aspect of the present invention includes a fuel reformer (60), a first flow rate adjustment valve (75), and a second flow rate adjustment valve (76). The fuel reforming unit converts a first hydrocarbon fuel (73) and a second hydrocarbon fuel (74) having a composition different from that of the first hydrocarbon fuel into a combustion chamber (40) of a scramjet engine (11). ) To generate reformed fuel (79) and cool the combustion chamber. The first flow rate adjusting valve adjusts a supply amount of the first hydrocarbon fuel to the fuel reforming unit. The second flow rate adjustment valve adjusts the supply amount of the second hydrocarbon fuel to the fuel reforming unit. The reformed fuel burns in the combustion chamber. The fuel reforming section includes a zeolite catalyst (83, 84, 85).

  The zeolitic catalyst includes an H-ZSM-5 catalyst.

  The fuel supply system further includes a sensor (78) for detecting the temperature of the combustion chamber, and a control unit (77) for controlling the first flow rate adjustment valve and the second flow rate adjustment valve based on the temperature. To do.

  The fuel reforming unit includes a platinum group catalyst.

  The zeolite catalyst is doped with the platinum group catalyst.

  The first hydrocarbon fuel and the second hydrocarbon fuel are any two selected from dodecene, JP-4 fuel, and JetA-1 fuel.

  The first hydrocarbon fuel and the second hydrocarbon fuel are any two selected from JP-7 fuel, JP-4 fuel, and JetA-1 fuel.

  A scramjet engine (11) according to a second aspect of the present invention includes an air compression unit (20), an injector (30), a combustion chamber (40), a fuel reforming unit (60), and a first flow rate adjustment. A valve (75) and a second flow rate adjustment valve (76) are provided. The air compressing unit compresses air to generate compressed air (70). The injector injects reformed fuel (79) into the compressed air. The reformed fuel burns in the combustion chamber. The fuel reforming unit thermally decomposes the first hydrocarbon fuel (73) and the second hydrocarbon fuel (74) having a composition different from that of the first hydrocarbon fuel with heat from the combustion chamber. The reformed fuel is generated and the combustion chamber is cooled. The first flow rate adjusting valve adjusts a supply amount of the first hydrocarbon fuel to the fuel reforming unit. The second flow rate adjustment valve adjusts the supply amount of the second hydrocarbon fuel to the fuel reforming unit. The fuel reforming section includes a zeolite catalyst (83, 84, 85).

  A scramjet engine operating method according to a third aspect of the present invention is a scramjet comprising an air compression section (20), an injector (30), a combustion chamber (40), and a fuel reforming section (60). This is an operation method of the engine (11). The operating method is that the air compressor compresses air to generate compressed air (70), the injector injects reformed fuel (79) into the compressed air, and the combustion chamber Combusting the reformed fuel. The operation method is such that the fuel reforming section supplies the first hydrocarbon fuel (73) and the second hydrocarbon fuel (74) having a composition different from that of the first hydrocarbon fuel by heat from the combustion chamber. Pyrolyzing to produce the reformed fuel and cooling the combustion chamber; supplying the first hydrocarbon-based fuel to the fuel reforming section; and second carbonizing to the fuel reforming section Adjusting the supply amount of the hydrogen-based fuel separately. The fuel reforming section includes a zeolite catalyst (83, 84, 85).

  According to the present invention, in a scramjet engine that thermally decomposes fuel with heat from a combustion chamber to generate reformed fuel and burns the reformed fuel in the combustion chamber, the composition of the reformed fuel is kept constant, and There are provided a fuel supply system, a scramjet engine, and an operation method thereof capable of separately controlling the cooling capacity of a combustion chamber by thermal decomposition of fuel and the amount of reformed fuel produced.

FIG. 1 is a schematic view of an aircraft equipped with a scramjet engine according to a first embodiment of the present invention. FIG. 2 is a schematic diagram of the fuel supply system according to the first embodiment. FIG. 3 is a cross-sectional view of the fuel reforming unit according to the first embodiment. FIG. 4 is a schematic view of a fuel decomposition test apparatus. FIG. 5A is a graph showing a GC-MS measurement result of JP-4 fuel. FIG. 5B is a graph showing a GC-MS measurement result of a decomposition product when JP-4 fuel is thermally decomposed using an H-ZSM-5 catalyst. FIG. 6A is a graph showing a GC-MS measurement result of dodecene. FIG. 6B is a graph showing a GC-MS measurement result of a decomposition product when dodecene is thermally decomposed using an H-ZSM-5 catalyst. FIG. 7A is a graph showing a GC-MS measurement result of JetA-1 fuel. FIG. 7B is a graph showing a GC-MS measurement result of a decomposition product when JetA-1 fuel is thermally decomposed using an H-ZSM-5 catalyst. FIG. 8 is a schematic diagram of an apparatus for evaluating reaction heat in a fuel pyrolysis reaction. FIG. 9 is a graph showing the temperature distribution in the reaction tube when dodecene is continuously flowing through the reaction tube with and without a catalyst in the reaction tube of the reaction heat evaluation apparatus. FIG. 10 is a graph showing the temperature distribution in the reaction tube when JP-4 fuel is continuously flowing in the reaction tube with and without a catalyst in the reaction tube of the reaction heat evaluation apparatus. FIG. 11 is a cross-sectional view of a fuel reforming unit according to the second embodiment of the present invention. FIG. 12 is a graph showing a GC-MS measurement result of a decomposition product when dodecene is thermally decomposed using a Pt-doped H-ZSM-5 catalyst. FIG. 13 is a schematic view of a fuel supply system according to a modification of the second embodiment. FIG. 14 is a cross-sectional view of the upstream portion of the fuel reforming unit according to a modification of the second embodiment. FIG. 15 is a cross-sectional view of a downstream portion of a fuel reforming unit according to a modification of the second embodiment.

  With reference to the attached drawings, a fuel supply system, a scramjet engine, and a mode for operating the same according to the present invention will be described below.

(First embodiment)
The aircraft shown in FIG. 1 includes a fuselage 10 and a scramjet engine 11 according to the first embodiment of the present invention. The scramjet engine 11 includes an air compressor 20 that compresses air taken in from outside to generate compressed air, an injector 30 that injects reformed fuel into an air flow 70 of compressed air, and combustion in which the reformed fuel burns. The chamber 40 and the nozzle 50 which discharges | emits the combustion gas produced | generated by combustion of reformed fuel are provided.

  Here, the combustion chamber 40 becomes high temperature due to the combustion of the reformed fuel. In order to prevent damage to the combustion chamber 40, it is necessary to cool the combustion chamber 40. On the other hand, in order to appropriately perform combustion in the combustion chamber 40, it is necessary to manage the state of the combustion chamber 40.

  Referring to FIG. 2, the scramjet engine 11 includes a fuel supply system 15. The fuel supply system 15 includes a fuel reforming unit 60, a fuel tank 71, a fuel tank 72, a flow rate adjustment valve 75, a flow rate adjustment valve 76, an engine control unit 77, and a sensor 78. The fuel tank 71 carries a hydrocarbon fuel 73 and supplies the hydrocarbon fuel 73 to the fuel reforming unit 60 via a flow rate adjustment valve 75. The fuel tank 72 is equipped with a hydrocarbon fuel 74 and supplies the hydrocarbon fuel 74 to the fuel reforming unit 60 via the flow rate adjustment valve 76. The hydrocarbon-based fuel 74 has a composition different from that of the hydrocarbon-based fuel 73. The flow rate adjusting valves 75 and 76 can separately adjust the supply amounts of the hydrocarbon-based fuels 73 and 74 to the fuel reforming unit 60. The fuel reformer 60 thermally decomposes the hydrocarbon fuels 73 and 74 with heat from the combustion chamber 40 to generate a reformed fuel 79. Since the thermal decomposition is an endothermic reaction, the fuel reforming unit 60 cools the combustion chamber 40. Such cooling is sometimes referred to as regenerative cooling. The injector 30 injects the reformed fuel 79 into the compressed air stream 70. The reformed fuel 79 burns in the combustion chamber 40. The sensor 78 detects the state of the combustion chamber 40. The engine control unit 77 controls the flow rate adjustment valves 75 and 76 based on the state of the combustion chamber 40. By controlling the flow rate adjusting valves 75 and 76 based on the state of the combustion chamber 40, the supply amounts of the hydrocarbon-based fuels 73 and 74 to the fuel reforming unit 60 are adjusted based on the state of the combustion chamber 40. Since the amount of reformed fuel 79 produced may change when the amount of supply of the hydrocarbon fuels 73 and 74 to the fuel reforming unit 60 changes, the injection amount of the reformed fuel 79 by the injector 30 is the hydrocarbon fuel. It is desirable to match the supply amounts of 73 and 74. Therefore, the engine control unit 77 controls the injector 30 so as to correspond to the control of the flow rate adjusting valves 75 and 76.

  The hydrocarbon fuels 73 and 74 may be supplied in a liquid state to the fuel reforming unit 60, and vaporization and thermal decomposition may be performed in the fuel reforming unit 60. Alternatively, the hydrocarbon fuels 73 and 74 may be supplied to the fuel reforming unit 60 after being vaporized by a vaporizer (not shown).

  Referring to FIG. 3, the fuel reforming unit 60 includes a fuel pipe 80 provided so as to surround the combustion chamber 40 and a zeolite-based catalyst 83. The zeolite-based catalyst 83 is carried on the inner wall 81 of the fuel pipe 80 and the surface of the granular carrier 82 disposed in the fuel pipe 80. When passing through the fuel pipe 80, the hydrocarbon fuels 73 and 74 are thermally decomposed by the heat from the combustion chamber 40, and the reformed fuel 79 is generated. This thermal decomposition is promoted by the zeolitic catalyst 83. Since the fuel reforming section 60 includes the zeolite-based catalyst 83, even if the ratio of the supply amount of the hydrocarbon-based fuel 73 and the supply amount of the hydrocarbon-based fuel 74 changes, the test result described later supports. The composition of the quality fuel 79 is kept constant. Therefore, the combustion in the combustion chamber 40 is stabilized. On the other hand, when the ratio of the supply amount of the hydrocarbon fuel 73 and the supply amount of the hydrocarbon fuel 74 changes so as to support the test results described later, the heat of the hydrocarbon fuels 73 and 74 in the fuel reformer 60 is changed. The amount of heat absorbed by decomposition changes. Therefore, the cooling capacity of the combustion chamber 40 by the thermal decomposition of the hydrocarbon fuels 73 and 74 and the reformed fuel 79 are controlled by separately adjusting the supply amounts of the hydrocarbon fuels 73 and 74 by the flow rate adjusting valves 75 and 76. The production amount can be controlled separately.

  Since the H-ZSM-5 catalyst has a high effect of promoting the above-described thermal decomposition, the use of the H-ZSM-5 catalyst as the zeolite catalyst 83 can reduce the size of the fuel reforming unit 60.

  Further, when the temperature of the combustion chamber 40 is selected as the state of the combustion chamber 40 to be managed (when the sensor 78 detects the temperature of the combustion chamber 40), the endothermic amount due to thermal decomposition of the hydrocarbon fuels 73 and 74 is changed. By doing so, the temperature of the combustion chamber 40 can be managed efficiently.

(Fuel decomposition test 1)
When the fuel cracking test is performed and the hydrocarbon fuel is pyrolyzed using the H-ZSM-5 catalyst, which is one of the zeolite catalysts, the composition of the pyrolysis product is the same even if the hydrocarbon fuel is different. Showed that Hereinafter, the fuel decomposition test will be described.

  With reference to FIG. 4, the test method of the fuel decomposition test will be described. The fuel decomposition test apparatus includes a syringe 101, a vaporizer 102, a reaction tube 103, an H-ZSM-5 catalyst layer 104, an electric furnace 105, a temperature sensor 106, and a GC-MS (gas mass) 107. . The vaporizer 102 was set to 150 ° C. An H-ZSM-5 catalyst layer 104 was disposed in the reaction tube 103. The reaction tube 103 was heated in the electric furnace 105 so that the temperature of the H-ZSM-5 catalyst layer 104 was 600 ° C. The GC-MS 107 includes a gas chromatograph and a mass spectrometer. Helium gas was used as a carrier gas. The carrier gas flow rate was set to 10 ml / min. Fuel was injected into the vaporizer 102 with the syringe 101. The amount of fuel injected by the syringe 101 was 0.1 μl. The fuel was vaporized by the vaporizer 102, and the vaporized fuel was thermally decomposed in the reaction tube 103. The pyrolysis product was measured by GC-MS107. As the fuel, JetA-1 fuel, dodecene, and JP-4 fuel were used. These jet fuels are hydrocarbon fuels.

  Next, test results of the fuel decomposition test will be described.

  FIG. 5A is a graph showing a GC-MS measurement result of JP-4 fuel. The horizontal axis represents the retention time, and the vertical axis represents the peak area. Pentane, hexane, heptane, cyclohexane, toluene, heptane, octane, nonane, decane, undecane, dodecane, tetradecane, and pentadecane peaks were detected.

  FIG. 5B is a graph showing a GC-MS measurement result of a decomposition product when JP-4 fuel is thermally decomposed using an H-ZSM-5 catalyst. The horizontal axis represents the retention time, and the vertical axis represents the peak area. C1 component (C1), C2 component (C2), C3 component (C3), C4 component (C4), and C6 component (C6 +) ) Peak was detected.

  As is clear from the comparison between FIG. 5A and FIG. 5B, the pyrolysis of JP-4 fuel using the H-ZSM-5 catalyst reduces the proportion of high carbon number components, and reduces the proportion of low carbon number components. The percentage increased.

  FIG. 6A is a graph showing a GC-MS measurement result of dodecene. The horizontal axis represents the retention time, and the vertical axis represents the peak area.

  FIG. 6B is a graph showing a GC-MS measurement result of a decomposition product when dodecene is thermally decomposed using an H-ZSM-5 catalyst. The horizontal axis represents the retention time, and the vertical axis represents the peak area. Peaks of ethylene, 1-propene, butene, benzene, toluene, ethylbenzene, p-xylene, o-xylene, styrene, 1,3,5-trimethylbenzene, naphthalene and 1-methylnaphthalene were detected.

  As is clear from the comparison between FIG. 6A and FIG. 6B, the proportion of the high carbon number component is decreased and the proportion of the low carbon number component is increased by pyrolyzing dodecene using the H-ZSM-5 catalyst. did.

  FIG. 7A is a graph showing a GC-MS measurement result of JetA-1 fuel. The horizontal axis represents the retention time, and the vertical axis represents the peak area. Octane, nonane, decane, undecane, dodecane, tridecane, and tetradecane peaks were detected.

  FIG. 7B is a graph showing a GC-MS measurement result of a decomposition product when JetA-1 fuel is thermally decomposed using an H-ZSM-5 catalyst. The horizontal axis represents the retention time, and the vertical axis represents the peak area. Peaks of the component (C1) having 1 carbon, the component (C2) having 2 carbons, the component (C3) having 3 carbons, and the component (C6 +) having 6 or more carbons were detected.

  As is clear from the comparison between FIG. 7A and FIG. 7B, the proportion of the high carbon number component is reduced by pyrolyzing the JetA-1 fuel using the H-ZSM-5 catalyst, and the low carbon number component. The percentage increased.

  As is clear from the comparison of FIGS. 5B, 6B, and 7B, the decomposition products obtained by pyrolyzing JP-4 fuel, dodecene, and JetA-1 fuel using H-ZSM-5 catalyst have the same composition. Met. On the other hand, as is apparent from the comparison of FIGS. 5A, 6A, and 7A, the compositions of JP-4 fuel, dodecene, and JetA-1 fuel were different from each other.

(Decomposition reaction heat evaluation test)
The composition of JP-4 fuel, dodecene, and JetA-1 fuels were different from each other, but the cracked products of JP-4 fuel, dodecene, and JetA-1 fuel were pyrolyzed using H-ZSM-5 catalyst. Since the composition of the product was the same, the reaction heat (endothermic amount) by thermal decomposition of JP-4 fuel, dodecene, and JetA-1 fuel is considered to be different from each other. A cracking reaction heat evaluation test was conducted to verify this for dodecene and JP-4 fuels. Hereinafter, the decomposition reaction heat evaluation test will be described.

  The test method of the decomposition reaction heat evaluation test will be described with reference to FIG. The apparatus for evaluating reaction heat in the thermal decomposition reaction of fuel includes a reaction tube 113, an H-ZSM-5 catalyst layer 114, an electric furnace 115, a thermocouple 116, and a thermocouple protection tube 117. The reaction tube 113 has an outer diameter of 17.3 mm, an inner diameter of 12.7 mm, and a length of 400 mm. A Z coordinate is defined along a straight line parallel to the axial direction of the reaction tube 113. The reaction tube 113 is disposed in the electric furnace 115. The length of the electric furnace 115 in the axial direction of the reaction tube 113 is 400 mm. A thermocouple 116 protected by a thermocouple protection tube 117 is disposed in the reaction tube 113. The thermocouple protection tube 117 has an outer diameter of 4 mm and an inner diameter of 2 mm. The Z coordinate at the center of the reaction tube 113 is set to 0 mm. A plurality of temperature measurement points 116a are arranged in a range from a position where the Z coordinate in the reaction tube 113 is −145 mm to a position where +145 mm. The H-ZSM-5 catalyst layer 114 is disposed at the center (Z coordinate: 0 mm) of the reaction tube 113. The H-ZSM-5 catalyst layer 114 is supported by a not-shown eye plate and glass wool. The thickness of the H-ZSM-5 catalyst layer 114 is 10 mm. With and without the H-ZSM-5 catalyst layer 114, the temperature of the plurality of temperature measurement points 116 a was measured with the thermocouple 116 while continuously allowing the vaporized fuel 120 to flow through the reaction tube 113. The reaction tube 113 was heated in the electric furnace 115 so that the temperature of the temperature measurement point 116a at the center (Z coordinate: 0 mm) of the reaction tube 113 in the absence of the H-ZSM-5 catalyst layer 114 was 600 ° C. The fuel LHSV (Liquid Hourly Space Velocity) was set to 200. As the fuel, dodecene and JP-4 fuel were used.

  FIG. 9 shows the temperature measurement results for dodecene. The horizontal axis indicates the temperature measurement position (Z coordinate), and the vertical axis indicates the temperature. The temperature at the temperature measurement point 116a at the center (Z coordinate: 0 mm) of the reaction tube 113 with the H-ZSM-5 catalyst layer 114 decreased by 90 ° C. compared to the case without the H-ZSM-5 catalyst layer 114. .

  FIG. 10 shows the temperature measurement results for JP-4 fuel. The horizontal axis indicates the temperature measurement position (Z coordinate), and the vertical axis indicates the temperature. The temperature at the temperature measuring point 116a at the center (Z coordinate: 0 mm) of the reaction tube 113 when the H-ZSM-5 catalyst layer 114 is present is reduced by 50 ° C. compared to the case where the H-ZSM-5 catalyst layer 114 is not present. .

  As is clear from FIGS. 9 and 10, the reaction heat (endothermic amount) due to thermal decomposition of JP-4 fuel and dodecene was different from each other.

  From the above test results, as the hydrocarbon fuels 73 and 74, for example, any two selected from JetA-1 fuel, dodecene, and JP-4 fuel can be used. Since dodecene corresponds to JP-7 fuel, JP-7 fuel may be used instead of dodecene. Three or more hydrocarbon fuels may be used.

(Second Embodiment)
Next, a fuel supply system 15 according to a second embodiment of the present invention will be described. The fuel supply system 15 according to the present embodiment is the same as the fuel supply system 15 according to the first embodiment except for the fuel reforming unit 60.

  Referring to FIG. 11, the fuel reforming unit 60 according to the present embodiment includes a platinum group doped zeolite catalyst 84. The platinum group doped zeolite catalyst 84 is a zeolite catalyst doped with a platinum group catalyst such as a platinum catalyst, a palladium catalyst, or a rhodium catalyst. The platinum group doped zeolite catalyst 84 is supported on the inner wall 81 of the fuel pipe 80 and the surface of the granular carrier 82 disposed in the fuel pipe 80. When passing through the fuel pipe 80, the hydrocarbon fuels 73 and 74 are thermally decomposed by the heat from the combustion chamber 40, and the reformed fuel 79 is generated. This thermal decomposition is promoted by the platinum group doped zeolite catalyst 84.

  In this embodiment, the decomposition product produced | generated by the thermal decomposition reaction by a zeolitic catalyst is further decomposed | disassembled by the thermal decomposition reaction by a platinum group catalyst. Therefore, most of the reformed fuel 79 is a low-carbon hydrocarbon that is easily combusted.

  In addition, since the H-ZSM-5 catalyst has a high effect of promoting thermal decomposition, when the platinum group-doped zeolite catalyst 84 is formed by doping the H-ZSM-5 catalyst with a platinum group catalyst, the fuel reforming portion 60 is reduced in size. Can be

(Fuel decomposition test 2)
A fuel cracking test showed that most of the pyrolysis products were methane, which is easily combusted, when hydrocarbon fuels were pyrolyzed using H-ZSM-5 catalyst doped with platinum catalyst. . Hereinafter, the fuel decomposition test will be described.

  A test method for the fuel decomposition test will be described. The fuel decomposition test apparatus shown in FIG. 4 was used. The test method is the same as the test method described above, except that the H-ZSM-5 catalyst layer 104 is doped with a platinum catalyst. Dodecene was used as fuel.

  Next, test results of the fuel decomposition test will be described.

  FIG. 12 is a graph showing GC-MS measurement results of decomposition products when dodecene was thermally decomposed using an H-ZSM-5 catalyst doped with a platinum catalyst. The horizontal axis represents the retention time, and the vertical axis represents the peak area. A large peak for methane and a small peak for benzene were detected. Most of the dodecene was decomposed to methane by pyrolysis using H-ZSM-5 catalyst doped with platinum catalyst.

  As shown in FIGS. 6A and 6B, a large amount of aromatic compounds such as benzene and toluene were produced by thermal decomposition of dodecene with H-ZSM-5 catalyst. These aromatic compounds are more stable and less likely to vaporize than straight-chain hydrocarbons, and are easily deposited on the catalyst as a highly viscous solid component. When solid components are deposited on the catalyst, the contact between the fuel and the catalyst is hindered, and the aromatic compound may cause coking.

  As shown in FIGS. 6B and 12, the aromatic compound was decomposed by the platinum catalyst doped in the H-ZSM-5 catalyst.

  As shown in FIGS. 5B, 6B, and 7B, the composition of cracked products is the same when JP-4 fuel, dodecene, and JetA-1 fuel are pyrolyzed using H-ZSM-5 catalyst. JP-4 fuel and JetA-1 fuel are also considered to be largely decomposed into methane by pyrolysis using an H-ZSM-5 catalyst doped with a platinum catalyst.

  Further, since the platinum catalyst, rhodium catalyst, and palladium catalyst are all platinum group catalysts, it is considered that the same effect can be obtained even when a rhodium catalyst or a palladium catalyst is used instead of the platinum catalyst.

  In addition, since the fuel reforming unit 60 includes the platinum group doped zeolite catalyst 84, the fuel reforming unit 60 is downsized compared to the case where the fuel reforming unit 60 includes the platinum group catalyst and the zeolite catalyst separately. .

(Modification of the second embodiment)
Next, a fuel supply system 15 according to a modification of the second embodiment will be described. The fuel supply system 15 according to this modification is the same as the fuel supply system 15 according to the second embodiment, except that the fuel reforming unit 60 includes a platinum group catalyst and a zeolite-based catalyst separately.

  Referring to FIG. 13, the fuel reforming unit 60 according to this modification includes an upstream portion 61 and a downstream portion 62. The hydrocarbon fuels 73 and 74 flow from the upstream portion 61 to the downstream portion 62 while being thermally decomposed.

  Referring to FIG. 14, the upstream portion 61 includes a zeolitic catalyst 85. The zeolite-based catalyst 85 is carried on the inner wall 81 of the fuel pipe 80 and the surface of the granular carrier 82 disposed in the fuel pipe 80. When passing through the fuel pipe 80 of the upstream portion 61, the hydrocarbon fuels 73 and 74 are thermally decomposed by the heat from the combustion chamber 40 to generate intermediate decomposition products. This thermal decomposition is promoted by the zeolitic catalyst 85. The zeolitic catalyst 85 is preferably an H-ZSM-5 catalyst.

  Referring to FIG. 15, the downstream portion 62 includes a platinum group catalyst 86. The platinum group catalyst 86 is supported on the inner wall 81 of the fuel pipe 80 and the surface of the granular carrier 82 disposed in the fuel pipe 80. When passing through the fuel pipe 80 of the downstream portion 62, the intermediate decomposition product is thermally decomposed by the heat from the combustion chamber 40, and the reformed fuel 79 is generated. This thermal decomposition is promoted by the platinum group catalyst 86. The platinum group catalyst 86 includes a platinum catalyst, a palladium catalyst, or a rhodium catalyst.

  The fuel supply system, the scramjet engine, and the operation method thereof according to the present invention have been described above with reference to the embodiments. However, the fuel supply system, the scramjet engine, and the operation method thereof according to the present invention are not limited to the above embodiments. It is possible to add a change to the said embodiment or to combine the said embodiment. For example, the scramjet engine 11 may be applied to a flying object or a rocket instead of being applied to an aircraft.

DESCRIPTION OF SYMBOLS 10 ... Airframe 11 ... Scramjet engine 15 ... Fuel supply system 20 ... Air compression part 30 ... Injector 40 ... Combustion chamber 50 ... Nozzle 60 ... Fuel reforming part 61 ... Upstream part 62 ... Downstream part 70 ... Airflow of compressed air 71, 72 ... Fuel tanks 73, 74 ... Hydrocarbon fuels 75, 76 ... Flow rate adjusting valve 77 ... Engine control unit 78 ... Sensor 79 ... Reformed fuel 80 ... Fuel pipe 81 ... Inner wall 82 ... Carrier 83 ... Zeolite catalyst 84 ... platinum group doped zeolite catalyst 85 ... zeolite catalyst 86 ... platinum group catalyst 101 ... syringe 102 ... vaporizer 103 ... reaction tube 104 ... H-ZSM-5 catalyst layer 105 ... electric furnace 106 ... temperature sensor 107 ... GC-MS
113 ... Reaction tube 114 ... H-ZSM-5 catalyst layer 115 ... Electric furnace 116 ... Thermocouple 116a ... Temperature measuring point 117 ... Thermocouple protection tube 120 ... Vaporized fuel

Claims (9)

The first hydrocarbon fuel and the second hydrocarbon fuel having a composition different from that of the first hydrocarbon fuel are pyrolyzed by heat from the combustion chamber of the scramjet engine to generate a reformed fuel and the combustion chamber A fuel reforming section for cooling the
A first flow rate adjusting valve for adjusting a supply amount of the first hydrocarbon fuel to the fuel reforming unit;
A second flow rate adjusting valve that adjusts a supply amount of the second hydrocarbon fuel to the fuel reforming unit ;
A control unit for controlling the first flow rate adjustment valve and the second flow rate adjustment valve ;
The reformed fuel burns in the combustion chamber;
The fuel reforming section includes a zeolite catalyst ,
The control unit controls the first flow rate adjustment valve and the second flow rate adjustment valve to supply the first hydrocarbon-based fuel to the fuel reforming unit and to the fuel reforming unit. A fuel supply system for separately adjusting a supply amount of the second hydrocarbon fuel. The fuel supply system according to claim 1,
The zeolitic catalyst includes an H-ZSM-5 catalyst. The fuel supply system according to claim 1 or 2,
Sensor for detecting the temperature of the combustion chamber
Further comprising,
The control unit is a fuel supply system that controls the first flow rate adjustment valve and the second flow rate adjustment valve based on the temperature . The fuel supply system according to any one of claims 1 to 3,
The fuel reforming unit includes a platinum group catalyst. The fuel supply system according to claim 4,
A fuel supply system in which the platinum group catalyst is doped in the zeolite catalyst. A fuel supply system according to any one of claims 1 to 5,
The first hydrocarbon fuel and the second hydrocarbon fuel are any two selected from dodecene, JP-4 fuel, and JetA-1 fuel. A fuel supply system according to any one of claims 1 to 5,
The first hydrocarbon fuel and the second hydrocarbon fuel are any two selected from JP-7 fuel, JP-4 fuel, and JetA-1 fuel. An air compressor that compresses air to generate compressed air;
An injector for injecting reformed fuel into the compressed air;
A combustion chamber in which the reformed fuel burns;
A first hydrocarbon fuel and a second hydrocarbon fuel having a composition different from that of the first hydrocarbon fuel are pyrolyzed by heat from the combustion chamber to generate the reformed fuel and cool the combustion chamber. A fuel reforming unit that performs
A first flow rate adjusting valve for adjusting a supply amount of the first hydrocarbon fuel to the fuel reforming unit;
A second flow rate adjusting valve that adjusts a supply amount of the second hydrocarbon fuel to the fuel reforming unit ;
A control unit for controlling the first flow rate adjustment valve and the second flow rate adjustment valve ;
The fuel reforming section includes a zeolite catalyst ,
The control unit controls the first flow rate adjustment valve and the second flow rate adjustment valve to supply the first hydrocarbon-based fuel to the fuel reforming unit and to the fuel reforming unit. A scramjet engine that separately adjusts the supply amount of the second hydrocarbon fuel . An operation method of a scramjet engine including an air compression unit, an injector, a combustion chamber, and a fuel reforming unit,
The air compression unit compresses air to generate compressed air;
The injector injects reformed fuel into the compressed air;
Burning the reformed fuel in the combustion chamber;
The fuel reforming unit thermally decomposes the first hydrocarbon fuel and the second hydrocarbon fuel having a composition different from that of the first hydrocarbon fuel with heat from the combustion chamber to generate the reformed fuel. And cooling the combustion chamber,
Separately adjusting the supply amount of the first hydrocarbon fuel to the fuel reforming section and the supply amount of the second hydrocarbon fuel to the fuel reforming section,
The fuel reforming section includes a zeolite-based catalyst.

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