Thermal field coupling dynamically adjustable ammonia cracker and control method

Abstract

The invention discloses a thermal field coupling dynamically-adjustable ammonia cracker and a control method, the thermal field coupling dynamically-adjustable ammonia cracker comprises an ammonia preheating device and an ammonia cracking reaction device, the ammonia preheating device comprises a combustion preheating chamber and a controllable pure ammonia burner, the combustion preheating chamber comprises a combustion cavity and an ammonia preheating cavity, the ammonia preheating cavity surrounds the periphery of the combustion cavity, and the controllable pure ammonia burner is arranged in the combustion cavity. The controllable pure ammonia burner comprises an ammonia fuel spray head and an air rotational flow assembly, the air rotational flow assembly comprises a plurality of rotational flow fan blades, the distances between the rotational flow fan blades in the circumferential direction are adjustable, the ammonia cracking reaction device comprises a tail gas inlet pipe, a mixed gas heat exchange cavity and an ammonia cracking reaction pipe, and the ammonia cracking reaction pipe is arranged in the mixed gas heat exchange cavity; an inlet of the mixed gas heat exchange cavity is communicated with the tail gas inlet pipe and the combustion cavity at the same time, the ammonia cracking reaction pipe is communicated with the ammonia preheating cavity, and an ammonia cracking catalyst is arranged in the ammonia cracking reaction pipe. The requirements for the high ammonia cracking rate and the high energy utilization efficiency are met, and meanwhile the hydrogen production amount can be dynamically adjusted according to the hydrogen requirement amount of the ammonia internal combustion engine.

Description

Technical Field

[0001] The present invention relates to the field of energy-saving and new energy vehicles, and in particular to a thermal field coupled dynamically adjustable ammonia cracker and a control method thereof. Background Art

[0002] Ammonia, as a zero-carbon fuel, can be used in ammonia internal combustion engines to push pistons to do work. However, ammonia is difficult to ignite, so hydrogen needs to be supplied according to the hydrogen demand under different working conditions of the ammonia internal combustion engine. The on-board ammonia cracking hydrogen production device can meet the online hydrogen production, but ammonia cracking is a violent endothermic reaction, and the reaction temperature usually needs to reach about 450°C for efficient ammonia cracking, so a matching heat source is needed to supply it. Although the ammonia internal combustion engine produces 200-500°C exhaust gas when working, it is not enough to stably support the efficient cracking of ammonia. Burning a part of ammonia to provide a heat source can produce ammonia combustion gas, which is a high-grade heat source for ammonia cracking. However, the temperature of ammonia combustion gas produced by traditional ammonia burners can usually reach 1300°C, which is too high for ammonia cracking. In addition, the amount of hydrogen required under different working conditions of the ammonia internal combustion engine is different, so the amount of ammonia to be cracked is also different, and the heat required for ammonia preheating and ammonia cracking reaction is also different. At present, how to effectively couple the above variables for thermal energy management so that the ammonia power system can match the energy required for preheating / reaction under any working conditions has not yet been found an effective solution. Summary of the invention

[0003] The object of the present invention is to provide a thermal field coupled dynamically adjustable ammonia cracker and a control method to solve one or more technical problems existing in the prior art and at least provide a beneficial choice or create conditions.

[0004] The technical solutions adopted to solve the above technical problems are: The present invention provides a thermal field coupled dynamically adjustable ammonia cracker, comprising: An ammonia preheating device comprises a combustion preheating chamber and a controllable pure ammonia burner, wherein the combustion preheating chamber comprises a combustion chamber and an ammonia preheating chamber, wherein the ammonia preheating chamber surrounds the outer periphery of the combustion chamber and has a partition heat exchange relationship with the combustion chamber, wherein the controllable pure ammonia burner is coaxially installed at one end of the combustion chamber, wherein the other end of the combustion chamber is provided with a smoke exhaust port, wherein the controllable pure ammonia burner comprises an ammonia fuel nozzle and an air swirl assembly coaxially arranged inside and outside, wherein the air swirl assembly comprises a plurality of swirl blades arranged at annular intervals on the outer periphery of the ammonia fuel nozzle, wherein the plurality of swirl blades are arranged obliquely along the circumferential direction, wherein the spacing between the plurality of swirl blades along the circumferential direction is adjustable, and an air swirl channel is formed between two adjacent swirl blades; An ammonia cracking reaction device comprises an exhaust gas intake pipe, a mixed gas heat exchange chamber and at least one ammonia cracking reaction tube, wherein the ammonia cracking reaction tube is arranged in the mixed gas heat exchange chamber and has a partition wall heat exchange relationship with the mixed gas heat exchange chamber, the exhaust gas intake pipe is used to collect the exhaust gas of an ammonia internal combustion engine, the inlet of the mixed gas heat exchange chamber is communicated with the exhaust gas intake pipe and the smoke exhaust port at the same time, the ammonia cracking reaction tube is communicated with the ammonia preheating chamber, and an ammonia cracking catalyst is arranged inside the ammonia cracking reaction tube.

[0005] The beneficial effects of the present invention are: During use, ammonia fuel is sprayed into the combustion chamber through an ammonia fuel nozzle, and air enters the combustion chamber in a swirling manner through an air swirl channel formed between the swirl blades, and is mixed with the ammonia fuel to burn and generate a swirling flame and ammonia combustion gas, wherein the flame is heated by an ammonia preheating chamber at the periphery of the combustion chamber, and at the same time, ammonia is passed into the ammonia preheating chamber, and after being preheated, enters the ammonia cracking reaction tube, and the ammonia combustion gas is mixed with the exhaust gas of the ammonia internal combustion engine and passed into the mixed gas heat exchange chamber, and the ammonia cracking reaction tube is heated. According to different hydrogen requirements, the circumferential spacing between the swirl blades is adjusted. Specifically, a part of the swirl blades can be made to fit together, and the other part of the swirl blades can be separated at a certain angle, so as to achieve the control of the strength of the swirl degree of the air in the combustion chamber, thereby controlling The heat transfer efficiency of the flame through the combustion chamber to the ammonia preheating chamber and the temperature of the ammonia combustion gas generated by the ammonia combustion are controlled. In this way, according to the different hydrogen requirements of the ammonia internal combustion engine, different amounts of ammonia to be cracked can be preheated with matching heat, and the ammonia combustion gas can be further mixed with the exhaust gas of the ammonia internal combustion engine to form a mixed gas, and enter the mixed gas heat exchange chamber to heat the ammonia cracking reaction tube, wherein the mixed gas temperature can also be adjusted by the air cyclone component, so that the required amount of ammonia after preheating can receive matching heat energy from the mixed gas in the ammonia cracking reaction tube, thereby achieving the purpose of efficient ammonia cracking and hydrogen production; in summary, the ammonia cracker of the present invention can achieve high ammonia cracking rate and high energy utilization efficiency requirements, and at the same time, the hydrogen production amount can be dynamically adjusted according to the hydrogen requirement of the ammonia internal combustion engine.

[0006] As a further improvement of the above technical solution, the swirl blades include fixed swirl blades and adjustable swirl blades, and the windward ends of the fixed swirl blades and the adjustable swirl blades are both connected with guide plates extending in the axial direction; The controllable pure ammonia burner includes an ammonia fuel delivery pipe, a burner shell and an air pipeline; The air swirl assembly includes a stator air disk and a plurality of rotor air disks which are coaxially and relatively rotatably arranged at the end of the burner housing in sequence along the axial direction, the stator air disk is provided with a plurality of the fixed swirl blades at annular intervals, each of the rotor air disks is provided with a plurality of the adjustable swirl blades at annular intervals, the adjustable swirl blades are connected to the rotor air disk through the guide plate so that the fixed swirl blades and the adjustable swirl blades are located in the same plane in the axial direction, the ammonia fuel nozzle is arranged at the center of the stator air disk, the ammonia fuel delivery pipe penetrates into the burner housing and is connected to the ammonia fuel nozzle, and the air pipeline is communicated with the air swirl channel through the interior of the burner housing.

[0007] As a further improvement of the above technical solution, the stator wind disc comprises a center hole disc body, a stator outer ring spaced and sleeved on the outer periphery of the center hole disc body, a plurality of the fixed swirl blades are fixed between the center hole disc body and the stator outer ring, the center hole disc body is provided with at least two ignition electrode holes, a plurality of air holes, and an ammonia nozzle hole, the ammonia fuel nozzle is installed in the ammonia nozzle hole, the ignition electrode hole is provided with a high-energy ignition electrode, and the plurality of air holes are connected to the inside of the burner shell; The rotor wind disk comprises a rotor inner ring and a rotor outer ring which are sleeved together with an inner and outer spacing, and the guide plate is connected between the rotor inner ring and the rotor outer ring.

[0008] As a further improvement of the above technical solution, the controllable pure ammonia burner further includes a plurality of driving mechanisms, and the plurality of driving mechanisms are respectively connected to the plurality of rotor wind discs in a transmission manner.

[0009] As a further improvement of the above technical solution, the thickness of the swirl blades is gradually increased from the inside to the outside in the radial direction; An annular air-distributing plate is arranged inside the burner shell, and the air-distributing plate is arranged between the air pipeline and the air cyclone component.

[0010] As a further improvement of the above technical solution, an ammonia input pipeline is connected to one end of the ammonia preheating chamber near the smoke exhaust port, and an ammonia flow control valve is installed on the ammonia input pipeline. An ammonia output pipeline is connected to one end of the ammonia preheating chamber near the controllable pure ammonia burner, and the ammonia output pipeline is connected to the ammonia cracking reaction tube; The combustion chamber comprises a cylindrical chamber wall body, which is a heat-conducting component. A plurality of fins are distributed at annular intervals on the outer peripheral surface of the chamber wall body, and the fins are axially extended and arranged in the ammonia preheating chamber.

[0011] As a further improvement of the above technical solution, the inlet of the mixed gas heat exchange chamber is connected to a mixing chamber, a baffle plate is provided in the mixing chamber, and the smoke exhaust port and the outlet of the exhaust gas intake pipe are respectively provided on the mixing chamber on both sides of the baffle plate; The outlet of the mixed gas heat exchange chamber is connected with a three-way catalytic device.

[0012] As a further improvement of the above technical solution, a plurality of ammonia cracking reaction tubes are evenly distributed in the mixed gas heat exchange chamber; The mixed gas heat exchange chamber comprises a heat exchange chamber insulation cover, in which a plurality of baffles are arranged in a staggered manner along the axial direction of the ammonia cracking reaction tube to form a serpentine mixed gas flow path, and the ammonia cracking reaction tube passes through the baffles.

[0013] As a further improvement of the above technical solution, an ammonia distribution chamber is provided at one end of the heat exchange chamber insulation cover close to the outlet of the mixed gas heat exchange chamber, and the ammonia preheating chamber is connected with the inlets of the multiple ammonia cracking reaction tubes through the ammonia distribution chamber. A cracked gas exhaust pipe is provided at one end of the heat exchange chamber insulation cover close to the inlet of the mixed gas heat exchange chamber, and the cracked gas exhaust pipe is connected with the outlets of the multiple ammonia cracking reaction tubes.

[0014] The present invention also provides a control method applicable to the ammonia cracker, comprising: Obtaining the hydrogen required for an ammonia internal combustion engine; When the ammonia internal combustion engine is in a high hydrogen demand condition, the circumferential spacing between all the swirl blades is adjusted to a first preset value, and the flow area of ​​the air swirl channel between two adjacent swirl blades is reduced to enhance the swirl degree of the air in the combustion chamber, improve the heat transfer efficiency between the flame passing through the combustion chamber and the ammonia preheating chamber, and increase the amount of ammonia introduced into the ammonia preheating chamber; When the ammonia internal combustion engine is in a low hydrogen demand condition, the swirl blades are adjusted to fit closely to expand the flow area of ​​the air swirl channel, so as to reduce the swirl degree of the air in the combustion chamber, reduce the heat transfer efficiency between the flame passing through the combustion chamber and the ammonia preheating chamber, and reduce the amount of ammonia introduced into the ammonia preheating chamber; When the ammonia internal combustion engine is in a working condition between high hydrogen demand and low hydrogen demand, a part of the swirl blades are adjusted to fit tightly, and the circumferential spacing between the other part of the swirl blades is adjusted to a second preset value to control the amount of ammonia introduced into the ammonia preheating chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described below in conjunction with the accompanying drawings and embodiments; Figure 1 This is a structural schematic diagram of an embodiment of the ammonia cracker provided by the present invention; Figure 2is a cross-sectional view of an embodiment of the ammonia cracker provided by the present invention; Figure 3 This is a schematic structural diagram of an embodiment of the controllable pure ammonia burner provided by the present invention; Figure 4 This is an exploded view of an embodiment of the controllable pure ammonia burner provided by the present invention; Figure 5 This is a cross-sectional view of an embodiment of the controllable pure ammonia burner provided by the present invention; Figure 6 is a flow chart of an embodiment of the control method provided by the present invention; Figure 7 This is a schematic diagram of the operation of an embodiment of the ammonia cracker provided by the present invention under the condition of ammonia internal combustion engine with high hydrogen demand; Figure 8 This is a schematic diagram of the operation of an embodiment of the ammonia cracker provided by the present invention under the condition of low hydrogen demand of an ammonia internal combustion engine; Fig. 9 This is a schematic diagram of the operation of a controllable pure ammonia burner provided by the present invention, one embodiment of which is under the condition of high hydrogen demand of an ammonia internal combustion engine; Fig.10 This is a schematic diagram of the operation of a controllable pure ammonia burner provided by the present invention, one embodiment of which is under the condition of low hydrogen demand of an ammonia internal combustion engine; Fig.11 This is a schematic diagram of the controllable pure ammonia burner provided by the present invention, and one embodiment thereof works under the condition of ammonia internal combustion engine with high hydrogen demand. Fig.12 The invention provides a controllable pure ammonia burner, and an operating schematic diagram of one embodiment thereof under the condition of ammonia internal combustion engine with low hydrogen demand. DETAILED DESCRIPTION

[0016] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0017] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0018] In the description of the present invention, if there are words such as "several", it means one or more, "more" means more than two, greater than, less than, exceed, etc. are understood as not including the number, and above, below, within, etc. are understood as including the number.

[0019] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0020] Reference Figure 1 to Figure 12 The thermal field coupled dynamically adjustable ammonia cracker of the present invention comprises an ammonia preheating device and an ammonia cracking reaction device.

[0021] like Figure 1 and Figure 2 As shown, the ammonia preheating device of the embodiment of the present invention comprises a combustion preheating chamber 2 and a controllable pure ammonia burner 1, wherein the combustion preheating chamber 2 comprises a combustion chamber 21 and an ammonia preheating chamber 22. The combustion chamber 21 of the present embodiment is extended left and right. In other embodiments, the combustion chamber 21 may extend in other directions. The left end of the combustion chamber 21 is a smoke exhaust end, and the right end is a combustion end. A smoke exhaust port 213 is provided at the left end of the combustion chamber 21. The controllable pure ammonia burner 1 is installed at the right end of the combustion chamber 21, and the axial direction of the controllable pure ammonia burner 1 extends left and right. The controllable pure ammonia burner 1 is arranged to spray and burn toward the left.

[0022] The ammonia preheating chamber 22 surrounds the outer circumference of the combustion chamber 21, and there is a wall heat exchange relationship between the ammonia preheating chamber 22 and the combustion chamber 21. Specifically, the combustion chamber 21 includes a cylindrical chamber wall body 211, and the chamber wall body 211 is a heat-conducting component. Heat exchange between the combustion chamber 21 and the ammonia preheating chamber 22 is achieved through the chamber wall body 211. In order to reduce heat loss, the outer wall of the ammonia preheating chamber 22 is a heat-insulating component.

[0023] The ammonia preheating chamber 22 of the embodiment of the present invention is connected to an ammonia input pipe 8 and an ammonia output pipe 222. When in use, ammonia enters the ammonia preheating chamber 22 from the ammonia input pipe 8, and the heat generated by the combustion of the controllable pure ammonia burner 1 preheats the ammonia in the ammonia preheating chamber 22 through the chamber wall 211, and the preheated ammonia is discharged from the ammonia output pipe 222.

[0024] like Figures 3 to 5 As shown, the controllable pure ammonia burner 1 of this embodiment includes an ammonia fuel nozzle 14 and an air swirl assembly which are coaxially arranged inside and outside, and the air swirl assembly includes a plurality of swirl blades which are arranged at annular intervals on the outer peripheral side of the ammonia fuel nozzle 14, the plurality of swirl blades are arranged obliquely along the circumferential direction, and the circumferential spacing between the plurality of swirl blades is adjustable, so that an air swirl channel is formed between two adjacent swirl blades.

[0025] like Figures 3 to 5 As shown, the controllable pure ammonia burner 1 of the embodiment of the present invention includes an ammonia fuel delivery pipe 141, a burner shell 19 and an air pipeline 191, the air swirl assembly includes a stator wind disk 11 and a plurality of rotor wind disks 12, the stator wind disk 11 and the plurality of rotor wind disks 12 are coaxially relatively rotated in sequence from left to right along the axial direction, and the left end of the burner shell 19 is arranged, and the air pipeline 191 is connected to the right end of the burner shell 19, and the air pipeline 191 provides air to the inside of the burner shell 19, and the air flows from right to left in the burner shell 19, and then is sprayed into the combustion chamber 21 through the air swirl channel, and the ammonia fuel nozzle 14 is arranged at the center of the stator wind disk 11, the ammonia fuel delivery pipe 141 passes through the burner shell 19 from right to left and is connected to the ammonia fuel nozzle 14, and the ammonia fuel delivery pipe 141 provides fuel to the ammonia fuel nozzle 14, and this embodiment uses ammonia fuel, and the ammonia fuel is sprayed into the combustion chamber 21 through the ammonia fuel nozzle 14 and mixed with air for combustion.

[0026] The swirl blades of the embodiment of the present invention are divided into fixed swirl blades 111 and adjustable swirl blades 121, and the windward ends of the fixed swirl blades 111 and the adjustable swirl blades 121 are connected with guide plates 17 extending axially, and the stator wind disk 11 is provided with a plurality of fixed swirl blades 111 at annular intervals, and each rotor wind disk 12 is provided with a plurality of adjustable swirl blades 121 at annular intervals, wherein the adjustable swirl blades 121 are connected to the rotor wind disk 12 through the guide plates 17. It can be understood that the axial connection positions of different rotor wind disks 12 and the guide plates 17 are different, so that the fixed swirl blades 111 and the adjustable swirl blades 121 are located in the same plane in the axial direction, and the air intake flow path can be regularized between two adjacent guide plates 17, which helps to achieve a uniform swirl field.

[0027] Furthermore, the stator air disk 11 includes a center hole disk body 112, a stator outer ring 113 spaced apart on the outer periphery of the center hole disk body 112, a plurality of fixed swirl blades 111 fixed between the outer peripheral wall of the center hole disk body 112 and the inner peripheral wall of the stator outer ring 113, and the center hole disk body 112 is provided with at least two ignition electrode holes 114, a plurality of air holes 115, and an ammonia nozzle hole 116, the ammonia fuel nozzle 14 is installed in the ammonia nozzle hole 116, the ignition electrode hole 114 is provided with a high-energy ignition electrode 117, and the plurality of air holes 115 are connected to the interior of the burner shell 19. In the embodiment of the present invention, combustion ignition is achieved through the high-energy ignition electrode 117, and the air volume near the ammonia fuel nozzle 14 is increased through the plurality of air holes 115 to improve the success rate of ignition.

[0028] The rotor fan disk 12 of the embodiment of the present invention includes a rotor inner ring 123 and a rotor outer ring 122 that are fitted together with each other at an inner and outer interval. The guide plate 17 at the upper end of the adjustable swirl blade 121 is connected between the rotor inner ring 123 and the rotor outer ring 122. The stator fan disk 11 of the present invention is fixed relative to the burner housing 19, and the rotor fan disk 12 is rotatable relative to the burner housing 19. It can be understood that the adjustable swirl blade 121 is rotatable relative to the fixed swirl blade 111. In this embodiment, a plurality of adjustable swirl blades 121 are attached to each fixed swirl blade 111.

[0029] The controllable pure ammonia burner 1 of the present invention also includes multiple driving mechanisms, which are respectively connected to the multiple rotor wind discs 12 in transmission. The embodiment of the present invention drives a rotor wind disc 12 to rotate separately through the driving mechanism. The driving mechanism includes a circumferential rack 13 fixedly mounted on the outer periphery of the rotor outer ring 122, a stepper motor 131 fixed on the burner housing 19, and a gear 132 connected to the stepper motor 131 in transmission. The gear 132 is meshed with the circumferential rack 13, and the gear 132 is driven to rotate by the stepper motor 131. When the gear 132 is meshed with the circumferential rack 13, the rotor wind disc 12 is driven to rotate, thereby realizing precise control of the position of the adjustable swirl blades 121 on the rotor wind disc 12, thereby precisely controlling the swirl intensity of the air in the combustion chamber 21.

[0030] Among them, the thickness of the swirl blades in the embodiment of the present invention is gradually increased from the inside to the outside in the radial direction. It can be understood that the blade tip of the swirl blade is wider than the blade root, so that the swirl blades on the stator wind disk 11 and the rotor wind disks 12 at each stage can be tightly fitted without gaps, avoiding air turbulence.

[0031] At the same time, if Figure 5 As shown, an annular air uniforming plate 15 is arranged inside the burner housing 19. The air uniforming plate 15 is arranged between the air pipeline 191 and the air swirl component. The air uniforming plate 15 can also regularize the air intake flow path, which helps to achieve a uniform swirl field.

[0032] Furthermore, the ammonia input pipe 8 of the present embodiment is connected to one end of the ammonia preheating chamber 22 close to the smoke exhaust port 213, and the ammonia output pipe 222 is connected to one end of the ammonia preheating chamber 22 close to the controllable pure ammonia burner 1, so that the flow direction of ammonia in the ammonia preheating chamber 22 is opposite to the flame injection direction in the combustion chamber 21, forming convection heat exchange to improve the heat exchange efficiency.

[0033] The ammonia input pipeline 8 of the embodiment of the present invention is installed with an ammonia flow control valve 81, and the ammonia flow control valve 81 controls the flow of ammonia to be cracked to match the demand of the ammonia internal combustion engine.

[0034] In order to further improve the heat transfer effect, Figure 2As shown, a plurality of fins 212 are distributed at annular intervals on the outer peripheral surface of the cavity wall body 211, and the fins 212 are axially extended and arranged in the ammonia preheating cavity 22. It can be understood that both the cavity wall body 211 and the fins 212 have a wall heat exchange relationship with the ammonia preheating cavity 22, which is beneficial to the efficient preheating of ammonia.

[0035] like Figure 2 As shown, the ammonia cracking reaction device of the embodiment of the present invention comprises a tail gas intake pipe 5, a mixed gas heat exchange chamber 7 and at least one ammonia cracking reaction tube 3, wherein the ammonia cracking reaction tube 3 is extended to the left and right in the mixed gas heat exchange chamber 7, and the ammonia cracking reaction tube 3 and the mixed gas heat exchange chamber 7 have a partition wall heat exchange relationship. In some other embodiments, the ammonia cracking reaction tube 3 can be extended in other directions. The tail gas intake pipe 5 is used to collect the tail gas of the ammonia internal combustion engine. The inlet of the mixed gas heat exchange chamber 7 is connected to the tail gas intake pipe 5 and the smoke exhaust port 213 at the same time, and the ammonia cracking reaction tube 3 is connected to the ammonia preheating chamber 22. Figure 7 and Figure 8 As shown, an ammonia cracking catalyst 31 is arranged inside the ammonia cracking reaction tube 3 .

[0036] The ammonia preheated in the ammonia preheating chamber 22 enters the ammonia cracking reaction tube 3 , and the ammonia combustion gas is mixed with the tail gas of the ammonia internal combustion engine and passed into the mixed gas heat exchange chamber 7 to heat the ammonia cracking reaction tube 3 .

[0037] When in use, a part of the swirl blades can be made to fit together, and the other part of the swirl blades can be separated at a certain angle to achieve the control of the strength of the swirl degree of the air in the combustion chamber 21, thereby controlling the heat transfer efficiency of the flame through the combustion chamber 21 to the ammonia preheating chamber 22 and the temperature of the ammonia combustion gas generated by the ammonia combustion. In this way, according to the different hydrogen requirements of the ammonia internal combustion engine, different amounts of ammonia to be cracked can be preheated with matching heat, and the ammonia combustion gas can be further mixed with the exhaust gas of the ammonia internal combustion engine to form a mixed gas, and enter the mixed gas heat exchange chamber 7 to heat the ammonia cracking reaction tube 3, wherein the mixed gas temperature can also be adjusted by the air swirl component, so that the required amount of ammonia after preheating can receive matching heat energy from the mixed gas in the ammonia cracking reaction tube 3, thereby achieving the purpose of efficient ammonia cracking and hydrogen production.

[0038] In this embodiment, a plurality of ammonia cracking reaction tubes 3 are provided, and the plurality of ammonia cracking reaction tubes 3 are helpful to increase the heat exchange area and improve the heat exchange efficiency.

[0039] The mixed gas heat exchange chamber 7 of the present embodiment includes a heat exchange chamber insulation cover 71, which is used to insulate the mixed gas heat exchange chamber 7 to reduce heat loss. Tube sheets 73 are provided at both ends of the heat exchange chamber insulation cover 71, and both ends of the ammonia cracking reaction tube 3 are respectively fixed to the two tube sheets 73. A plurality of baffles 72 are arranged in a staggered manner along the axial direction of the ammonia cracking reaction tube 3 in the heat exchange chamber insulation cover 71 to form a serpentine mixed gas flow path. The ammonia cracking reaction tube 3 passes through the baffles 72, which helps to improve the heat exchange between the mixed gas and the ammonia cracking reaction tube 3.

[0040] The inlet of the mixed gas heat exchange chamber 7 is connected to the mixing chamber 6, and a vertically arranged baffle plate 61 is provided in the mixing chamber 6. The outlets of the exhaust gas inlet pipe 5 and the smoke exhaust port 213 are respectively arranged on the mixing chamber 6 on the left and right sides of the baffle plate 61. The baffle plate 61 can prevent the exhaust gas flow of the ammonia internal combustion engine from interfering with the ammonia combustion flame in the combustion chamber 21, which is conducive to the stable combustion of ammonia.

[0041] The outlet of the mixed gas heat exchange chamber 7 is connected to a three-way catalytic device 9, which can achieve efficient treatment of the mixed gas.

[0042] In this embodiment, an ammonia distribution chamber 223 is provided at one end of the heat exchange chamber insulation cover 71 near the outlet of the mixed gas heat exchange chamber 7, and an ammonia output pipeline 222 is connected with the inlet of multiple ammonia cracking reaction tubes 3 through the ammonia distribution chamber 223. A cracked gas exhaust pipeline 41 is provided at one end of the heat exchange chamber insulation cover 71 near the inlet of the mixed gas heat exchange chamber 7, and the cracked gas exhaust pipeline 41 is connected with the outlet of multiple ammonia cracking reaction tubes 3 through the cracked gas collecting chamber 4. In this way, the mixed gas in the heat exchange chamber insulation cover 71 and the ammonia in the ammonia cracking reaction tube 3 are arranged in opposite directions to form convection heat exchange, so as to improve the heat exchange efficiency.

[0043] Under different working conditions, the cylinders of an ammonia internal combustion engine have different hydrogen requirements. At the same time, the exhaust gas temperature and flow rate of an ammonia internal combustion engine under different working conditions are also different. For example, under light load and low speed working conditions, the cylinder hydrogen requirement is low, the exhaust gas temperature of the internal combustion engine is low, and the flow rate is small; while under heavy load and high speed working conditions, the cylinder hydrogen requirement is high, the exhaust gas temperature of the internal combustion engine is high, and the flow rate is large. According to the hydrogen requirement of the ammonia internal combustion engine and the exhaust gas temperature and flow rate, the embodiment of the present invention proposes a control method suitable for the ammonia cracker, such as Figure 6 As shown, the following steps are included: Step S100: obtaining the hydrogen requirement of the ammonia internal combustion engine; Step S200: When the ammonia internal combustion engine is in a high hydrogen demand condition, the circumferential spacing between all swirl blades is adjusted to a first preset value, and the flow area of ​​the air swirl channel between two adjacent swirl blades is reduced to enhance the swirl degree of the air in the combustion chamber 21, improve the heat transfer efficiency between the flame passing through the combustion chamber 21 and the ammonia preheating chamber 22, and increase the amount of ammonia introduced into the ammonia preheating chamber 22; Step S300: When the ammonia internal combustion engine is in a low hydrogen demand condition, the swirl blades are adjusted to fit closely to expand the flow area of ​​the air swirl channel, so as to reduce the swirl degree of the air in the combustion chamber 21, reduce the heat transfer efficiency between the flame passing through the combustion chamber 21 and the ammonia preheating chamber 22, and reduce the amount of ammonia introduced into the ammonia preheating chamber 22; Step S400: When the ammonia internal combustion engine is in a working condition between high hydrogen demand and low hydrogen demand, a part of the swirl blades are adjusted to fit tightly, and the circumferential spacing between the other part of the swirl blades is adjusted to a second preset value to control the amount of ammonia introduced into the ammonia preheating chamber 22.

[0044] In step S200, that is, under heavy load and high speed conditions with high hydrogen demand, Figure 7 As shown, the controllable pure ammonia burner 1 is adjusted to drive the multi-stage rotor fan disk 12 to rotate, so that the adjustable swirl blades 121 of the multi-stage rotor fan disk 12 and the fixed swirl blades 111 of the stator fan disk 11 are separated at a certain angle. At this time, the shape of the stator fan disk 1111 and the rotor fan disk 1212 is as shown in FIG. Fig. 9 As shown; at this time, the flow space between adjacent swirl blades is small, and the air blocking capacity is increased, resulting in an enhanced swirl degree of air in the combustion chamber 21; at this time, after the ammonia fuel and air enter the combustion chamber 21 and are ignited, the ammonia combustion flame is longer and the flame shape is coarse, thereby enhancing the flame through the chamber wall 211 and the fins 212 to the ammonia preheating chamber 22 The efficiency of heat transfer, but at this time, the ammonia combustion gas produced by the ammonia combustion is relatively low, about the sixth temperature point 1000°C; at this time, the ammonia flow control valve 81 is controlled to pass a large amount of ammonia, and a large amount of ammonia can also be heated to the second temperature point of about 400°C in the ammonia preheating chamber 22 with a higher heat transfer efficiency, and after preheating, it enters each ammonia cracking reaction tube 3 through the ammonia distribution chamber 223; the lower temperature of the ammonia combustion gas and the high temperature (about 450°C) and large flow rate of the ammonia internal combustion engine exhaust gas are The mixed gas is mixed in the mixing chamber 6 to generate a mixed gas with a large flow rate, and the temperature of the mixed gas can still reach the third temperature point of about 700°C; the mixed gas enters the mixed gas heat exchange chamber 7, flows along the serpentine motion path formed by multiple staggered baffles 72 and the heat exchange chamber insulation cover 71, and heats the ammonia cracking reaction tube 3; the ammonia cracking catalyst 31 in each ammonia cracking reaction tube 3 absorbs heat and can be maintained at a fourth temperature point of about 450°C, and a large amount of ammonia is efficiently cracked into a large amount of cracked gas containing hydrogen and nitrogen under the high space velocity condition at this time, and the cracked gas enters the cracked gas collecting chamber 4 and is discharged from the cracked gas discharge pipe 41 for use in the ammonia internal combustion engine; after the large flow mixed gas provides a large amount of reaction heat for the ammonia cracking reaction tube 3 for heat exchange, the residual temperature drops to the fifth temperature point, but still exceeds 250°C, and enters the three-way catalytic device 9 for efficient exhaust gas post-treatment.

[0045] In step S300, that is, under the condition of low hydrogen demand such as light load and low speed, Figure 8As shown, the controllable pure ammonia burner 1 is adjusted to drive the multi-stage rotor fan disk 12 to rotate, so that the adjustable swirl blades 121 of the multi-stage rotor fan disk 12 fit with the fixed swirl blades 111 of the stator fan disk 11. At this time, the shape of the stator fan disk 11 and the multi-stage rotor fan disk 12 is as shown in FIG. Fig.10 As shown; at this time, the flow space between adjacent swirl blades is larger, and the air blocking ability is reduced, resulting in a decrease in the swirl degree of the air in the combustion chamber 21; at this time, after the ammonia fuel and air enter the combustion chamber 21 and are ignited, the ammonia combustion flame length is shorter and the flame shape is thin, thereby reducing the flame through the chamber wall 211 and the fin 212 The heat transfer efficiency of the ammonia preheating chamber 22 is reduced, but at this time, the ammonia combustion gas generated by the ammonia combustion has a higher temperature and can reach the first temperature point of 1300°C; at this time, the ammonia flow control valve 81 is controlled to pass a smaller amount of ammonia, and a smaller amount of ammonia can also be heated to the second temperature point of about 400°C in the ammonia preheating chamber 22 with lower heat transfer efficiency, and after preheating, it enters each ammonia cracking reaction tube 3 through the ammonia distribution chamber 223; the higher temperature ammonia combustion gas and the low temperature (about 300°C) and small flow rate of the internal combustion engine exhaust gas The mixed gas is mixed in the mixing chamber 6 to generate a mixed gas with a lower flow rate, and the temperature of the mixed gas reaches the third temperature point of about 700°C; the mixed gas enters the mixed gas heat exchange chamber 7, flows along the serpentine motion path formed by a plurality of staggered baffles 72 and the heat exchange chamber insulation cover 71, and heats the ammonia cracking reaction tube 3; the ammonia cracking catalyst 31 in each ammonia cracking reaction tube 3 absorbs heat and can be maintained at a fourth temperature point of about 450°C, and a small amount of ammonia is efficiently cracked into a small amount of cracked gas containing hydrogen and nitrogen under the low space velocity condition at this time, and the cracked gas enters the cracked gas collecting chamber 4 and is discharged from the cracked gas discharge pipe 41 for use in the ammonia internal combustion engine; after the small flow mixed gas provides a certain amount of reaction heat for the ammonia cracking reaction tube 3 for heat exchange, the residual temperature drops to the fifth temperature point, but still exceeds 250°C, and enters the three-way catalytic device 9 for efficient exhaust gas post-treatment.

[0046] In step S400, that is, under other working conditions with different hydrogen demands, since the controllable pure ammonia burner 1 has a multi-stage rotor fan disk 12, the adjustable swirl blades 121 of a part of the multi-stage rotor fan disk 12 can be fitted with the fixed swirl blades 111 of the stator fan disk 11, and the adjustable swirl blades 121 of another part of the multi-stage rotor fan disk 12 can be separated from the fixed swirl blades 111 of the stator fan disk 11 at a certain angle, such as Figure 11-12As shown; in this way, the strength of the swirl degree of the air in the combustion chamber 21 can be controlled, and then the heat transfer efficiency of the flame through the chamber wall 211 and the fins 212 to the ammonia preheating chamber 22 and the temperature of the ammonia combustion gas generated by the ammonia combustion can be controlled; according to the different hydrogen requirements of the ammonia internal combustion engine, the ammonia flow control valve 81 is controlled to pass a matching amount of ammonia to preheat to the second temperature point of about 400°C, and enter each ammonia cracking reaction tube 3 through the ammonia distribution chamber 223223; different ammonia combustion gases and the internal combustion engine exhaust gas with matching temperature and flow are mixed The mixed gas is mixed in the combining chamber 6, enters the mixed gas heat exchange chamber 7, flows along the serpentine motion path formed by a plurality of staggered baffles 72 and the heat exchange chamber insulation cover 71, and heats the ammonia cracking reaction tube 3; the ammonia cracking catalyst 31 in each ammonia cracking reaction tube 3 absorbs heat and can be maintained at a fourth temperature point of about 450°C and efficiently cracks the required amount of ammonia into cracked gas containing hydrogen and nitrogen for use in the ammonia internal combustion engine; the residual temperature of the mixed gas drops to the fifth temperature point, but is still above 250°C, and enters the three-way catalytic device 9 for efficient exhaust gas post-treatment.

[0047] The above strategies can achieve high ammonia cracking rate and high energy utilization efficiency requirements. At the same time, the hydrogen production can be dynamically adjusted according to the hydrogen demand of the ammonia internal combustion engine, and efficient exhaust gas after-treatment can be achieved.

[0048] The preferred embodiments of the present invention are specifically described above, but the invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A thermal field coupled dynamically adjustable ammonia cracker, characterized in that: include: An ammonia preheating device comprises a combustion preheating chamber and a controllable pure ammonia burner, wherein the combustion preheating chamber comprises a combustion chamber and an ammonia preheating chamber, wherein the ammonia preheating chamber surrounds the outer periphery of the combustion chamber and has a partition heat exchange relationship with the combustion chamber, wherein the controllable pure ammonia burner is coaxially installed at one end of the combustion chamber, wherein the other end of the combustion chamber is provided with a smoke exhaust port, wherein the controllable pure ammonia burner comprises an ammonia fuel nozzle and an air swirl assembly coaxially arranged inside and outside, wherein the air swirl assembly comprises a plurality of swirl blades arranged at annular intervals on the outer periphery of the ammonia fuel nozzle, wherein the plurality of swirl blades are arranged obliquely along the circumferential direction, wherein the spacing between the plurality of swirl blades along the circumferential direction is adjustable, and an air swirl channel is formed between two adjacent swirl blades; An ammonia cracking reaction device comprises an exhaust gas intake pipe, a mixed gas heat exchange chamber and at least one ammonia cracking reaction tube, wherein the ammonia cracking reaction tube is arranged in the mixed gas heat exchange chamber and has a partition wall heat exchange relationship with the mixed gas heat exchange chamber, the exhaust gas intake pipe is used to collect the exhaust gas of an ammonia internal combustion engine, the inlet of the mixed gas heat exchange chamber is communicated with the exhaust gas intake pipe and the smoke exhaust port at the same time, the ammonia cracking reaction tube is communicated with the ammonia preheating chamber, and an ammonia cracking catalyst is arranged inside the ammonia cracking reaction tube.

2. The ammonia cracker according to claim 1, characterized in that: The swirl blades include fixed swirl blades and adjustable swirl blades, and the windward ends of the fixed swirl blades and the adjustable swirl blades are both connected with guide plates extending in the axial direction; The controllable pure ammonia burner includes an ammonia fuel delivery pipe, a burner shell and an air pipeline; The air swirl assembly includes a stator air disk and a plurality of rotor air disks which are coaxially and relatively rotatably arranged at the end of the burner housing in sequence along the axial direction, the stator air disk is provided with a plurality of the fixed swirl blades at annular intervals, each of the rotor air disks is provided with a plurality of the adjustable swirl blades at annular intervals, the adjustable swirl blades are connected to the rotor air disk through the guide plate so that the fixed swirl blades and the adjustable swirl blades are located in the same plane in the axial direction, the ammonia fuel nozzle is arranged at the center of the stator air disk, the ammonia fuel delivery pipe penetrates into the burner housing and is connected to the ammonia fuel nozzle, and the air pipeline is communicated with the air swirl channel through the interior of the burner housing.

3. The ammonia cracker according to claim 2, characterized in that: The stator wind disk comprises a center hole disk body, a stator outer ring spaced and sleeved on the outer periphery of the center hole disk body, a plurality of fixed swirl blades are fixed between the center hole disk body and the stator outer ring, the center hole disk body is provided with at least two ignition electrode holes, a plurality of air holes, and an ammonia nozzle hole, the ammonia fuel nozzle is installed in the ammonia nozzle hole, the ignition electrode hole is provided with a high-energy ignition electrode, and the plurality of air holes are connected to the inside of the burner shell; The rotor wind disk comprises a rotor inner ring and a rotor outer ring which are sleeved together with an inner and outer spacing, and the guide plate is connected between the rotor inner ring and the rotor outer ring.

4. The ammonia cracker according to claim 2, characterized in that: The controllable pure ammonia burner also includes a plurality of driving mechanisms, and the plurality of driving mechanisms are respectively connected to the plurality of rotor wind discs in a driving manner.

5. The ammonia cracker according to claim 2, characterized in that: The thickness of the swirl blades is gradually increased from the inside to the outside in the radial direction; An annular air-distributing plate is arranged inside the burner shell, and the air-distributing plate is arranged between the air pipeline and the air cyclone component.

6. The ammonia cracker according to claim 1, characterized in that: An ammonia input pipeline is connected to one end of the ammonia preheating chamber near the smoke exhaust port, and an ammonia flow control valve is installed on the ammonia input pipeline. An ammonia output pipeline is connected to one end of the ammonia preheating chamber near the controllable pure ammonia burner, and the ammonia output pipeline is connected to the ammonia cracking reaction tube; The combustion chamber comprises a cylindrical chamber wall body, which is a heat-conducting component. A plurality of fins are distributed at annular intervals on the outer peripheral surface of the chamber wall body, and the fins are axially extended and arranged in the ammonia preheating chamber.

7. The ammonia cracker according to claim, characterized in that: The inlet of the mixed gas heat exchange cavity is connected to a mixing chamber, a baffle plate is provided in the mixing chamber, and the smoke exhaust port and the outlet of the exhaust gas intake pipe are respectively provided on the mixing chamber on both sides of the baffle plate; The outlet of the mixed gas heat exchange chamber is connected with a three-way catalytic device.

8. The ammonia cracker according to claim 7, characterized in that: The mixed gas heat exchange chamber is evenly spaced with a plurality of ammonia cracking reaction tubes; The mixed gas heat exchange chamber comprises a heat exchange chamber insulation cover, in which a plurality of baffles are arranged in a staggered manner along the axial direction of the ammonia cracking reaction tube to form a serpentine mixed gas flow path, and the ammonia cracking reaction tube passes through the baffles.

9. The ammonia cracker according to claim 8, characterized in that: An ammonia distribution chamber is provided at one end of the heat exchange chamber insulation cover close to the outlet of the mixed gas heat exchange chamber, and the ammonia preheating chamber is connected with the inlets of the plurality of ammonia cracking reaction tubes through the ammonia distribution chamber. A cracking gas exhaust pipe is provided at one end of the heat exchange chamber insulation cover close to the inlet of the mixed gas heat exchange chamber, and the cracking gas exhaust pipe is connected with the outlets of the plurality of ammonia cracking reaction tubes.

10. A control method applicable to the ammonia cracker according to any one of claims 1 to 9, characterized in that: include: Obtaining the hydrogen required for an ammonia internal combustion engine; When the ammonia internal combustion engine is in a high hydrogen demand condition, the circumferential spacing between all the swirl blades is adjusted to a first preset value, and the flow area of ​​the air swirl channel between two adjacent swirl blades is reduced to enhance the swirl degree of the air in the combustion chamber, improve the heat transfer efficiency between the flame passing through the combustion chamber and the ammonia preheating chamber, and increase the amount of ammonia introduced into the ammonia preheating chamber; When the ammonia internal combustion engine is in a low hydrogen demand condition, the swirl blades are adjusted to fit closely to expand the flow area of ​​the air swirl channel, so as to reduce the swirl degree of the air in the combustion chamber, reduce the heat transfer efficiency between the flame passing through the combustion chamber and the ammonia preheating chamber, and reduce the amount of ammonia introduced into the ammonia preheating chamber; When the ammonia internal combustion engine is in a working condition between high hydrogen demand and low hydrogen demand, a part of the swirl blades are adjusted to fit tightly, and the circumferential spacing between the other part of the swirl blades is adjusted to a second preset value to control the amount of ammonia introduced into the ammonia preheating chamber.

Images