Engine device

Abstract

The invention provides an engine device which can improve ignition performance or combustion speed hysteresis of a mixed gas containing ammonia and hydrogen gas and can enable the mixed gas to be stably combusted with good exhaust gas properties. An engine device (1) for an ammonia co-combustion engine that operates by combusting at least a mixed gas of ammonia and hydrogen gas in a combustion chamber (21a) generates a mixed gas by supplying ammonia and hydrogen gas to the combustion chamber (21a), compresses the mixed gas in the combustion chamber (21a) and increases the temperature and pressure of the mixed gas, and controls the combustion chamber (21a) in accordance with the state of the mixed gas in the combustion chamber (21a). The gas mixture in the combustion chamber (21a) is ignited by an ignition device comprising a sub-fuel supply device (6) and a sub-fuel injection unit (26).

Description

Technical Field

[0001] The present invention relates to an engine device that operates by burning a mixture containing at least ammonia and hydrogen in a combustion chamber. Background Art

[0002] Conventional engine systems include ammonia-fueled engines that operate by burning a mixture containing ammonia and hydrogen in a combustion chamber. In these engine systems, there is a demand for improved properties (quality and state) of exhaust gas discharged from the ammonia-fueled engines.

[0003] For example, the ammonia co-firing engine disclosed in Patent Document 1 includes a combustion chamber, an ammonia supply mechanism for supplying ammonia to the combustion chamber, an air supply mechanism for supplying air to the combustion chamber, a liquid fuel supply mechanism for supplying liquid fuel to the combustion chamber, a fuel ratio setting mechanism for setting the ratio of the ammonia supply amount to the total supply amount of the liquid fuel and ammonia, and a supply timing control mechanism for controlling the timing of liquid fuel supply from the liquid fuel supply mechanism based on the ratio set by the fuel ratio setting mechanism. The ammonia co-firing engine performs control such that the timing of liquid fuel supply to the combustion chamber is delayed relative to the timing of starting the supply of ammonia and air, and the supply timing control mechanism advances the timing of liquid fuel supply as the ratio of ammonia supply amount set by the fuel ratio setting mechanism increases.

[0004] Furthermore, according to Patent Document 1, the supply timing control mechanism performs control such that the liquid fuel supplied by the liquid fuel supply mechanism is supplied in a multi-stage injection manner. In an ammonia-fueled engine, the advance angle for liquid fuel supply timing is set within a range of -25° to -70° relative to engine top dead center (TDC). The ratio of the ammonia supply amount to the total supply amount of liquid fuel and ammonia is within a range of 1% to 95%.

[0005] Furthermore, the control device for an internal combustion engine disclosed in Patent Document 2 is capable of supplying ammonia and a non-ammonia fuel that burns more easily than ammonia as fuel. The non-ammonia fuel is directly injected into the combustion chamber by a non-ammonia fuel injection device, and combustion of the air-fuel mixture in the combustion chamber is initiated by ignition of the injected non-ammonia fuel. The control device advances the injection timing of the non-ammonia fuel when the proportion of ammonia in the total fuel supplied to the internal combustion engine is high compared to when it is low. Alternatively, the control device increases the number of injections when the proportion of ammonia in the total fuel supplied to the internal combustion engine is high compared to when it is low.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2022-155927

[0009] Patent Document 2: Japanese Patent No. 5397541 Summary of the Invention

[0010] In an ammonia co-firing engine, increasing the ammonia supply rate and the combustion ratio toward 0-95% can reduce combustion stability, worsen exhaust gas properties, and increase the amount of NH3 and N2O contained in the exhaust gas. Conventional ammonia co-firing engines, such as those disclosed in Patent Document 1, improve exhaust gas properties by controlling the timing of liquid fuel supplied to the combustion chamber. However, controlling only the liquid fuel supply timing makes it difficult to simultaneously achieve both an increase in the ammonia co-firing ratio and improvements in combustion stability and exhaust gas properties.

[0011] Furthermore, in conventional ammonia-fueled engines, such as those disclosed in Patent Document 2, the timing of non-ammonia fuel injection is advanced or the number of injections is increased to improve the ignition quality of the non-ammonia fuel in order to ensure proper combustion of the mixture in the combustion chamber. However, in ammonia-fueled engines, while the ignition quality of the ammonia-containing mixture is improved by adding a non-ammonia fuel such as hydrogen, if excessive hydrogen is added, the ignition quality of the ammonia-containing mixture may be increased beyond the desired level, leading to abnormal combustion such as pre-ignition and difficulty in stable operation. Therefore, conventional ammonia-fueled engines have difficulty stably burning the ammonia-hydrogen mixture with good exhaust gas properties.

[0012] An object of the present invention is to provide an engine device that can improve the ignition performance or combustion speed lag of a mixture containing ammonia and hydrogen, and can stably burn the mixture with good exhaust gas properties.

[0013] In order to solve the above-mentioned problems, the engine device of the present invention is an engine device of an ammonia co-firing engine that operates by burning a mixture of at least ammonia and hydrogen in a combustion chamber. The engine device is characterized in that the ammonia and the hydrogen are supplied to the combustion chamber to generate the mixture, the mixture in the combustion chamber is compressed to increase its temperature and pressure, and the mixture in the combustion chamber is ignited by an ignition device according to the state of the mixture in the combustion chamber.

[0014] According to the present invention, it is possible to provide an engine device that can improve the ignition performance or combustion speed lag of a mixture gas containing ammonia and hydrogen and stably burn the mixture gas with good exhaust gas properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a mimetic diagram showing an engine device according to an embodiment of the present invention.

[0016] Figure 2 This is a simulation diagram showing an ammonia co-firing engine in an engine device according to an embodiment of the present invention.

[0017] Figure 3 This is a graph showing the relationship between the hydrogen mixing ratio of the main fuel and the air excess ratio in an ammonia co-firing engine, and the amount of nitrogen oxides in the exhaust gas in a mapped manner.

[0018] Figure 4 This is a diagram that represents the ignition timing for stable combustion of the air-fuel mixture in the form of a map.

[0019] Figure 5 This is a graph showing the relationship between the hydrogen mixing ratio of the main fuel and the emission ratio of unburned ammonia contained in the exhaust gas in an ammonia co-firing engine.

[0020] Figure 6 This is a graph showing the relationship between the hydrogen mixing ratio of the main fuel in an ammonia-fueled engine and the amount of nitrogen oxides contained in the exhaust gas.

[0021] Figure 7 This is a mimetic diagram showing an engine device according to another example of the present invention.

[0022] Description of Reference Numerals

[0023] 1--Engine unit, 2--Ammonia co-firing engine, 3--Intake passage, 4--Exhaust passage, 5--Main fuel supply device, 6--Auxiliary fuel supply device, 9--Control device, 11--Ammonia tank, 12--Ammonia supply unit, 13--Ammonia decomposition device, 14--Hydrogen tank, 15--Hydrogen supply unit, 16--Auxiliary fuel tank, 17--Auxiliary fuel supply unit, 20--Cylinder block, 21--Cylinder, 21a--Combustion chamber, 22--Crankcase, 23--Cylinder barrel, 24--Piston, 25--Cylinder head, 26--Auxiliary fuel injection unit, 35--Ammonia injection unit, 36--Hydrogen Injection unit, 41--knock sensor, 42--in-cylinder pressure sensor, 43--in-cylinder temperature sensor, 44--intake pressure sensor, 45--intake temperature sensor, 60--intake throttle valve, 61--supercharger, 61a--turbine, 61b--compressor, 61c--variable nozzle, 62--intercooler, 63--recirculation device, 63a--recirculation passage, 63b--recirculation cooler, 63c--recirculation valve, 64--intake bypass passage, 64a--intake bypass valve, 65--waste gate, 65a--waste gate valve, 66--rotation sensor. DETAILED DESCRIPTION

[0024] Referring to the accompanying drawings, an engine device 1 according to an embodiment of the present invention will be described. Figure 1 As shown, the engine device 1 includes an ammonia co-burning engine 2, an intake passage 3, an exhaust passage 4, a main fuel supply device 5, and a sub-fuel supply device 6. Furthermore, the engine device 1 includes a selective reduction catalyst 7, an ammonia adsorption catalyst 8, and a control device 9. Furthermore, the engine device 1 includes a knock sensor 41, an in-cylinder pressure sensor 42, an in-cylinder temperature sensor 43, an intake pressure sensor 44, and an intake temperature sensor 45.

[0025] In this embodiment, in particular, the engine device 1 is an ammonia-fueled engine device. The ammonia-fueled engine 2 is configured to operate by combusting a mixture containing at least ammonia and hydrogen within a combustion chamber 21a of each cylinder 21 formed by a cylinder bore 23 and a piston 24. In the engine device 1, a mixture of a main fuel containing at least ammonia and hydrogen and air is supplied to the combustion chamber 21a of each cylinder 21 of the ammonia-fueled engine 2. The supply of ammonia and hydrogen is controlled by a control device 9. In the engine device 1 of this embodiment, the mixture of the main fuel and at least one auxiliary fuel, such as a hydrocarbon-based fuel such as light oil, is combusted within the combustion chamber 21a. The supply of the auxiliary fuel is controlled by the control device 9.

[0026] The main fuel supply device 5 includes an ammonia tank 11 , an ammonia supply unit 12 , an ammonia decomposition device 13 , a hydrogen tank 14 , and a hydrogen supply unit 15 .

[0027] The ammonia tank 11 is filled with ammonia as the main fuel from the outside and stored in a liquid state. The ammonia supply unit 12 is constructed to have a pump connected to the ammonia tank 11, and is controlled by the control device 9 to introduce ammonia from the ammonia tank 11 and supply ammonia fuel in a liquid state or a gaseous state to the ammonia injection unit 35 of the ammonia co-firing engine 2.

[0028] The ammonia decomposition device 13 introduces ammonia from the ammonia tank 11, decomposes and reforms it to produce hydrogen fuel, and stores the gaseous hydrogen in the hydrogen tank 14. The hydrogen supply unit 15 is configured to include a pump connected to the hydrogen tank 14, and is controlled by the control device 9 to introduce hydrogen from the hydrogen tank 14 and supply the gaseous hydrogen fuel to the hydrogen injection unit 36 ​​of the ammonia co-firing engine 2.

[0029] The auxiliary fuel supply device 6 includes an auxiliary fuel tank 16 and an auxiliary fuel supply unit 17. The auxiliary fuel tank 16 stores an auxiliary fuel, which is a hydrocarbon-based fuel such as light oil, in a liquid state. The auxiliary fuel supply unit 17 includes a pump connected to the auxiliary fuel tank 16 and is controlled by the control device 9 to introduce the auxiliary fuel from the auxiliary fuel tank 16 and supply the liquid auxiliary fuel to the auxiliary fuel injection unit 26 of the ammonia-fueled engine 2.

[0030] The ammonia co-firing engine 2 is, for example, a four-stroke engine, and is configured such that a cylinder block 20 includes a plurality of cylinders 21 and a crankcase 22 (see Figure 2 ). Figure 1 In the figure, although four cylinders 21 are shown, the number of cylinders 21 is not limited to four. Figure 2 As shown, it is composed of a cylinder 23, a piston 24, and a cylinder head 25.

[0031] The cylinder tube 23 is formed in a cylindrical shape, for example, within the cylinder block 20. The piston 24 is slidably housed within the cylinder tube 23. A cylinder head 25 is mounted on the upper side of the cylinder tube 23. A combustion chamber 21a is formed inside the cylinder tube 23 and the cylinder head 25. The cylinder head 25 is provided with an auxiliary fuel injection unit 26 for injecting auxiliary fuel into the combustion chamber 21a.

[0032] For example, the auxiliary fuel injection unit 26 is comprised of a device such as an injector employing a droplet injection method that injects a small amount of auxiliary fuel. The auxiliary fuel injection unit 26 controls the auxiliary fuel injection timing, injection amount, injection pressure, and number of injections via the control unit 9. When the mixture of main fuel and air supplied to the combustion chamber 21a is compressed and heated and pressurized by the piston 24 approaching top dead center, the auxiliary fuel injection unit 26 injects a hydrocarbon-based liquid auxiliary fuel into the mixture, igniting the mixture and causing combustion. In other words, the auxiliary fuel supply device 6 and the auxiliary fuel injection unit 26 function as an ignition device for igniting the mixture in the combustion chamber 21a.

[0033] Each cylinder bore 23 of the plurality of cylinders 21 communicates with a crankcase 22, and a crankshaft 27 is rotatably supported on the crankcase 22. The piston 24 of each cylinder 21 is connected to the crankshaft 27 via a connecting rod 28, and the reciprocating motion of the piston 24 is converted into rotational motion of the crankshaft 27 via the connecting rod 28.

[0034] The cylinder head 25 has an intake port 29 and an exhaust port 30 communicating with the combustion chamber 21a of the cylinder 23, and includes an intake valve 31 and an exhaust valve 32 for opening and closing the intake port 29 and the exhaust port 30 with respect to the combustion chamber 21a, respectively.

[0035] The intake port 29 is connected to the intake passage 3 and introduces air supplied from the intake passage 3 into the combustion chamber 21a. The exhaust port 30 is connected to the exhaust passage 4 and discharges exhaust gas generated in the combustion chamber 21a into the exhaust passage 4. By opening the intake valve 31, a mixture of main fuel and air can be introduced into the combustion chamber 21a through the intake port 29. On the other hand, by opening the exhaust valve 32, the exhaust gas generated in the combustion chamber 21a can be discharged through the exhaust port 30.

[0036] The intake passage 3 is connected to the multiple cylinders 21 of the ammonia-fueled engine 2 and supplies compressed and cooled air to each cylinder 21. A mixture of air supplied from the intake passage 3 and main fuel supplied from the main fuel supply device 5 is supplied from the intake passage 3 to the combustion chamber 21a of each cylinder 21. For example, the intake passage 3 is connected to the ammonia-fueled engine 2 via an intake manifold 33. The intake manifold 33 has branching flow paths 33a that branch toward the multiple cylinders 21, and each branch flow path 33a is connected to a respective intake port 29.

[0037] In addition, an ammonia injection unit 35 for supplying ammonia fuel as a main fuel from the main fuel supply device 5 toward each combustion chamber 21a and a hydrogen injection unit 36 ​​for supplying hydrogen fuel as a main fuel are provided in the intake passage 3, the branch flow path 33a, the intake port 29 or the cylinder head 25.

[0038] The ammonia injection unit 35 and the hydrogen injection unit 36 ​​control the injection amount and injection timing of the ammonia fuel and the hydrogen fuel respectively by the control device 9, thereby controlling the excess air ratio in the mixed air supplied to the combustion chamber 21a. The ammonia injection unit 35 and the hydrogen injection unit 36 ​​can be composed of a supply valve or injector provided for each combustion chamber 21a to inject the ammonia fuel and the hydrogen fuel respectively.

[0039] in addition, Figure 2 In the figure, an example is shown in which the ammonia injection unit 35 and the hydrogen injection unit 36 ​​are provided in the intake manifold 33, injecting the ammonia fuel and the hydrogen fuel into the branch flow path 33a, and supplying the ammonia fuel and the hydrogen fuel to the combustion chamber 21a through the intake port 29. However, the present invention is not limited to this example. Alternatively, the ammonia injection unit 35 and the hydrogen injection unit 36 ​​may be provided in the intake passage 3, injecting the ammonia fuel and the hydrogen fuel into the intake passage 3, and supplying the ammonia fuel and the hydrogen fuel to the combustion chamber 21a through the intake passage 3 and the intake port 29. Alternatively, the ammonia injection unit 35 and the hydrogen injection unit 36 ​​may be provided in the cylinder bore 23 or the cylinder head 25, and injecting the ammonia fuel and the hydrogen fuel directly into the combustion chamber 21a for supply.

[0040] The exhaust passage 4 is connected to the multiple cylinders 21 of the ammonia-fueled engine 2, allowing exhaust gas generated in each cylinder 21 to flow and be discharged. For example, the exhaust passage 4 is connected to the ammonia-fueled engine 2 via an exhaust manifold 34. The exhaust manifold 34 has branching flow paths 34a that branch toward the multiple cylinders 21, and each branch flow path 34a is connected to a respective exhaust port 30.

[0041] The exhaust passage 4 is connected to a selective reduction catalyst 7 and an ammonia adsorption catalyst 8 on the downstream side in the exhaust direction for treating exhaust gas flowing through the exhaust passage 4. The selective reduction catalyst 7 and the ammonia adsorption catalyst 8 are arranged in series through the exhaust passage 4.

[0042] A selective reduction catalyst 7 is disposed in the exhaust passage 4. It selectively reduces nitrogen oxides contained in the exhaust gas flowing through the exhaust passage 4 using a reducing agent such as urea water, thereby purifying the exhaust gas of ammonia and nitrogen oxides. A reducing agent supply unit 7a is disposed in the exhaust passage 4 upstream of the selective reduction catalyst 7 in the exhaust direction. The reducing agent supply unit 7a supplies reducing agent to the selective reduction catalyst 7. The amount of reducing agent supplied by the reducing agent supply unit 7a is controlled by a control device 9.

[0043] For example, the selective reduction catalyst 7 causes ammonia and nitrogen oxides to undergo a reduction reaction in a one-to-one concentration or molar ratio (proportion), and the reducing agent supply unit 7a supplies the reducing agent in a one-to-one manner by being controlled by the control device 9 so that the concentration or molar ratio of ammonia and nitrogen oxides introduced into the selective reduction catalyst 7 together with the exhaust gas is controlled.

[0044] Ammonia adsorption catalyst 8 is disposed in exhaust passage 4 upstream of selective reduction catalyst 7 in the exhaust direction, and adsorbs ammonia contained in the exhaust gas flowing through exhaust passage 4, thereby purifying the exhaust gas of ammonia. Specifically, ammonia adsorption catalyst 8 reduces the concentration and / or number of moles of ammonia introduced into selective reduction catalyst 7 from the exhaust gas by adsorbing ammonia.

[0045] For example, the ammonia adsorption catalyst 8 may be composed of activated carbon, zeolite, Prussian blue, MOF (also known as porous metal complex or PCP (porous coordination polymer)), etc., as a material that adsorbs ammonia. Alternatively, in addition to having the function of adsorbing ammonia, the ammonia adsorption catalyst 8 may be composed of Fe ion-exchanged zeolite, Cu ion-exchanged zeolite, etc., as a material that reacts with nitrogen oxides.

[0046] The control unit 9 is a computer such as an ECU (Engine Control Unit) that controls the operation of the ammonia-burning engine 2. It includes a CPU, ROM, RAM, and other components and is configured to control various components of the ammonia-burning engine 2. The control unit 9 can store various programs for controlling the ammonia-burning engine 2 and controls the ammonia-burning engine 2 by reading and executing the programs.

[0047] The knock sensor 41 detects knocking of the ammonia-burning engine 2 and is provided, for example, in the cylinder block 20. The knock sensor 41 is connected to the control device 9 and transmits the detection result to the control device 9.

[0048] The cylinder pressure sensor 42 detects the pressure in the cylinder 21 (inside the combustion chamber 21a) and is provided in, for example, the cylinder head 25. The cylinder pressure sensor 42 is connected to the control device 9 and transmits the detection result to the control device 9.

[0049] The cylinder temperature sensor 43 detects the temperature in the cylinder 21 (inside the combustion chamber 21a) and is provided in, for example, the cylinder head 25. The cylinder temperature sensor 43 is connected to the control device 9 and transmits the detection result to the control device 9.

[0050] The intake air pressure sensor 44 detects the pressure of the intake air flowing into the ammonia-burning engine 2 and is provided, for example, in the intake manifold 33. The intake air pressure sensor 44 is connected to the control device 9 and transmits the detection result to the control device 9. In addition, while this embodiment describes an example in which the intake air pressure sensor 44 detects the pressure of a mixture of low-GHG fuel and air serving as intake air, the present invention is not limited to this example; the intake air pressure sensor 44 may also detect the pressure of either the low-GHG fuel or air serving as intake air.

[0051] The intake air temperature sensor 45 detects the temperature of the intake air flowing into the ammonia-burning engine 2 and is disposed, for example, in the intake manifold 33. The intake air temperature sensor 45 is connected to the control device 9 and transmits the detection result to the control device 9. In addition, while this embodiment describes an example in which the intake air temperature sensor 45 detects the temperature of the mixture of the low-GHG fuel and air serving as the intake air, the present invention is not limited to this example. The intake air temperature sensor 45 may also detect the temperature of the low-GHG fuel or air serving as the intake air.

[0052] in addition, Figure 2 Although the figure shows an example in which the engine device 1 includes a knock sensor 41, an in-cylinder pressure sensor 42, an in-cylinder temperature sensor 43, an intake pressure sensor 44, and an intake temperature sensor 45, the present invention is not limited to this example, and the engine device 1 only needs to include at least one of these sensors.

[0053] Next, supply control of the main fuel composed of ammonia and hydrogen and the auxiliary fuel which is a hydrocarbon-based fuel such as light oil in the engine device 1 will be described.

[0054] exist Figures 3 and 4 In FIG. 2 , the horizontal axis represents the hydrogen mixing ratio (hydrogen mixing proportion) of the main fuel composed of ammonia and hydrogen supplied to the combustion chamber 21 a , and the vertical axis represents the excess air ratio of the main fuel relative to the mixture supplied to the combustion chamber 21 a . Figure 3 In the figure, the relationship between the hydrogen mixing ratio and the excess air ratio is shown: a stable region 50 in which the ammonia co-firing engine 2 can operate stably is shown, and a mapping is used to show that within the stable region 50, the amount of nitrogen oxides such as nitrous oxide (N2O) contained in the exhaust gas increases in the direction indicated by the white arrow 51. Figure 4In the figure, the relationship between the hydrogen mixing ratio and the excess air ratio is shown: a stable region 50 in which the ammonia co-firing engine 2 can operate stably is shown, and the ignition timing for stably burning the mixture within the stable region 50 is shown by mapping, and the ignition timing is advanced in the direction indicated by the white arrow 52.

[0055] like Figure 3 As shown in FIG. 1 , although increasing the hydrogen mixing ratio or decreasing the excess air ratio can reduce nitrogen oxides such as nitrous oxide in the exhaust gas, excessive increase in the hydrogen mixing ratio or excessive decrease in the excess air ratio will cause the engine to deviate from the stable region 50 and easily cause premature ignition. Figure 4 As shown, although increasing the hydrogen mixing ratio or decreasing the excess air ratio can delay the ignition timing for stable combustion of the mixture, excessive increase in the hydrogen mixing ratio or excessive decrease in the excess air ratio will cause deviation from the stable region 50 and make premature ignition more likely to occur.

[0056] in addition, Figure 5 In FIG. 2 , the horizontal axis represents the hydrogen mixing ratio (hydrogen mixing ratio) of the main fuel composed of ammonia and hydrogen supplied to the combustion chamber 21 a , and the vertical axis represents the ratio of unburned ammonia contained in the exhaust gas to the ammonia supplied to the combustion chamber 21 a . Figure 6 In FIG. 1 , the horizontal axis represents the hydrogen mixing ratio (hydrogen mixing ratio) of the main fuel composed of ammonia and hydrogen supplied to the combustion chamber 21a, and the vertical axis represents the amount of nitrogen oxides such as nitrous oxide (N2O) contained in the exhaust gas. Figure 5 as well as Figure 6 As shown, in the engine device 1 , when the mixing ratio of hydrogen gas is increased to a predetermined value or more, pre-ignition is likely to occur.

[0057] Therefore, the control device 9 controls the following: based on the characteristics of the main fuel mixture composed of ammonia and hydrogen as described above, and in accordance with the state of the mixture in the combustion chamber 21a, the ignition device composed of the auxiliary fuel supply device 6 and the auxiliary fuel injection unit 26 injects the auxiliary fuel into the mixture in the combustion chamber 21a at an ignition timing that allows the mixture to burn stably, thereby igniting the mixture and causing it to burn. The ignition timing that allows the mixture to burn stably is the time when the ignition device composed of the auxiliary fuel supply device 6 and the auxiliary fuel injection unit 26 is to ignite the mixture in the combustion chamber 21a before it reaches a predetermined auto-ignition temperature or predetermined auto-ignition pressure and self-ignites as the piston 2 approaches top dead center.

[0058] For example, in the engine device 1, as Figure 4As shown, an ignition timing that enables stable combustion of the mixture is pre-set based on the relationship between the hydrogen mixing ratio and the excess air ratio of the mixture. A map or mathematical formula that can appropriately obtain the set ignition timing is pre-stored in the control device 9 as ignition timing information. Furthermore, the control device 9 controls the ignition of the mixture by the ignition device based on the ignition timing information. Specifically, the control device 9 monitors the hydrogen mixing ratio and excess air ratio of the mixture, uses the current hydrogen mixing ratio and excess air ratio as input parameters, and uses the map or mathematical formula of the ignition timing information to obtain the ignition timing at which the mixture should be ignited. Based on this ignition timing, the control device 9 controls the ignition device to ignite the mixture.

[0059] Furthermore, the engine device 1 may obtain various data on the ignition timing of the air-fuel mixture from various data on the hydrogen mixing ratio and the excess air ratio of the air-fuel mixture while the ammonia-burning engine 2 is previously operated experimentally. A map may be created and stored in advance for the relationship between the hydrogen mixing ratio and the excess air ratio of the air-fuel mixture. The map indicates the ignition timing that enables the air-fuel mixture to stably combust within the stable region 50. Alternatively, the engine device 1 may obtain various data on the ignition timing from various data on the hydrogen mixing ratio and the excess air ratio of the air-fuel mixture while the ammonia-burning engine 2 is actually operated, and the accumulated data may be used to create and store a map for the relationship between the hydrogen mixing ratio and the excess air ratio of the air-fuel mixture. The map indicates the ignition timing that enables the air-fuel mixture to stably combust within the stable region 50.

[0060] Alternatively, in the engine device 1, instead of the aforementioned ignition timing information, at least one injection parameter among the auxiliary fuel injection timing, injection amount, injection pressure, and injection frequency that enables stable combustion of the mixture is pre-set based on the relationship between the hydrogen mixing ratio and the excess air ratio of the mixture. A map or mathematical formula that can appropriately obtain the set injection parameter is pre-stored in the control device 9 as auxiliary fuel injection information. The control device 9 then controls ignition of the mixture by the ignition device based on the auxiliary fuel injection information. Specifically, the control device 9 monitors the hydrogen mixing ratio and excess air ratio of the mixture, uses the current hydrogen mixing ratio and excess air ratio as input parameters, and uses the map or mathematical formula of the auxiliary fuel injection information to obtain at least one injection parameter among the auxiliary fuel injection timing, injection amount, injection pressure, and injection frequency that should be used to ignite the mixture. The control device 9 then controls the ignition device based on this injection parameter to ignite the mixture.

[0061] In addition, the engine device 1 can obtain various data on injection parameters such as the injection period, injection amount, injection pressure and number of injections of the auxiliary fuel for various data on the hydrogen mixing ratio and excess air ratio of the mixture when the ammonia co-firing engine 2 is operated in advance. Thus, a map is prepared for the relationship between the hydrogen mixing ratio and excess air ratio of the mixture and stored in advance, wherein the map represents the injection parameters such as the injection period, injection amount, injection pressure and number of injections of the auxiliary fuel that can stably burn the mixture within the range of the stable area 50. Alternatively, the engine device 1 may also obtain and accumulate various data on injection parameters such as the injection period, injection amount, injection pressure, and number of injections of the auxiliary fuel for various data on the hydrogen mixing ratio and excess air ratio of the mixture while actually operating the ammonia co-firing engine 2, thereby creating a map for the relationship between the hydrogen mixing ratio and excess air ratio of the mixture and storing the map, wherein the map represents the injection parameters such as the injection period, injection amount, injection pressure, and number of injections of the auxiliary fuel that can stably burn the mixture within the range of the stable area 50.

[0062] In addition, when the control device 9 controls the ignition device based on the ignition timing information or auxiliary fuel injection information as described above, it determines premature ignition by determining the occurrence or prediction of premature ignition of the ammonia co-firing engine 2, and / or determines deterioration of exhaust gas properties by determining the occurrence or prediction of deterioration of exhaust gas properties of the ammonia co-firing engine 2.

[0063] For example, the control device 9 determines whether pre-ignition has occurred or is predicted to occur in the ammonia-fueled engine 2, and / or whether deterioration in exhaust gas properties has occurred or is predicted to occur, based on the detection results of at least one of the knock sensor 41, the in-cylinder pressure sensor 42, the in-cylinder temperature sensor 43, the intake air pressure sensor 44, and the intake air temperature sensor 45. Specifically, the control device 9 may determine that pre-ignition has occurred if the knock sensor 41 detects abnormal knock. Furthermore, the control device 9 may determine that pre-ignition has occurred if the in-cylinder pressure sensor 42 or the in-cylinder temperature sensor 43 detects an abnormal increase in pressure or temperature in the combustion chamber 21a. Furthermore, the control device 9 may determine that pre-ignition is predicted if the intake air pressure sensor 44 or the intake air temperature sensor 45 detects an abnormal increase in pressure or temperature of the intake air supplied to the combustion chamber 21a.

[0064] Moreover, the control device 9 performs avoidance control for premature ignition and / or deterioration of exhaust gas properties of the ammonia co-firing engine 2 based on the detection results of at least one sensor among the knock sensor 41, the in-cylinder pressure sensor 42, the in-cylinder temperature sensor 43, the intake pressure sensor 44, and the intake temperature sensor 45.

[0065] Normally, when it is not determined that premature ignition has occurred in the ammonia co-firing engine 2 or that premature ignition is predicted and / or that deterioration of exhaust gas properties has occurred or that deterioration of exhaust gas properties is predicted, the control device 9 controls in the following manner: the main fuel is supplied with a hydrogen mixing ratio and an ammonia mixing ratio pre-set for the specified target output of the ammonia co-firing engine 2 so that the mixture can be stably burned.

[0066] To address this, for example, if the control device 9 determines, based on the detection results of the various sensors, that pre-ignition has occurred or is predicted, the control device 9 reduces the mixing ratio of hydrogen in the main fuel and / or increases the mixing ratio of ammonia, thereby controlling the output of the ammonia-burning engine 2 to a predetermined target output. Alternatively, if the control device 9 determines, based on the detection results of the various sensors, that exhaust gas properties have deteriorated or are predicted to deteriorate, the control device 9 reduces the mixing ratio of hydrogen in the main fuel and / or increases the mixing ratio of ammonia, thereby controlling the output of the ammonia-burning engine 2 to a predetermined target output.

[0067] As described above, according to the present invention, the ammonia co-firing engine device, that is, the engine device 1, which operates by burning at least a mixture of ammonia and hydrogen in the combustion chamber 21a, supplies ammonia and hydrogen to the combustion chamber 21a to generate a mixture, compresses the mixture in the combustion chamber 21a to increase its temperature and pressure, and ignites the mixture in the combustion chamber 21a according to the state of the mixture in the combustion chamber 21a through the ignition device composed of the auxiliary fuel supply device 6 and the auxiliary fuel injection part 26.

[0068] For example, the ignition device ignites the air-fuel mixture by injecting an auxiliary fuel such as light oil or a hydrocarbon-based fuel. Furthermore, in the above-described embodiment, an example is described in which the ignition device is composed of the auxiliary fuel supply device 6 and the auxiliary fuel injection unit 26. However, the present invention is not limited to this example. The ignition device may also be configured to include a spark plug, and ignite the air-fuel mixture by discharge from the spark plug.

[0069] Thus, the engine device 1 of the present invention can control ignition according to the state of the mixture containing ammonia and hydrogen. This allows the ignition device to ignite the mixture before the mixture reaches high temperature and pressure and undergoes auto-ignition. This improves the ignition quality and combustion rate lag of the mixture containing ammonia and hydrogen, and suppresses premature ignition and knock, thereby enabling stable combustion of the mixture and improving exhaust gas properties.

[0070] In addition, the engine device 1 of the present invention includes a control device 9, which has: ignition timing information representing a predetermined ignition timing for the relationship between the mixing ratio of ammonia and hydrogen and the air excess ratio of the mixture, and the control device 9 controls the ignition of the mixture implemented by the ignition device based on the ignition timing information.

[0071] Accordingly, the engine device 1 can control the ignition timing according to the state of the mixture containing ammonia and hydrogen, thereby being able to more reliably determine the period before the mixture reaches high temperature and high pressure and self-ignites, thereby being able to ignite the mixture using the ignition device.

[0072] In addition, the engine device 1 of the present invention is provided with a control device 9 having auxiliary fuel injection information when the ignition device is configured to ignite the mixture by injecting an auxiliary fuel which is a hydrocarbon-based fuel such as light oil. The auxiliary fuel injection information represents at least one of the injection period, injection amount, injection pressure and number of injections of the hydrocarbon-based fuel predetermined based on the relationship between the mixing ratio of ammonia and hydrogen and the excess air ratio of the mixture. The control device 9 controls the ignition performed by the ignition device based on the auxiliary fuel injection information.

[0073] Thus, the engine device 1 can control the injection timing, injection amount, injection pressure, injection frequency, etc. of the hydrocarbon fuel according to the state of the mixture containing ammonia and hydrogen, thereby further improving the stable combustion of the mixture and the exhaust gas properties.

[0074] In addition, the engine device 1 of the present invention includes: a knock sensor 41 for detecting knock of the ammonia co-firing engine 2, an in-cylinder pressure sensor 42 for detecting pressure in the combustion chamber 21a of the ammonia co-firing engine 2, an in-cylinder temperature sensor 43 for detecting temperature in the combustion chamber 21a of the ammonia co-firing engine 2, an intake pressure sensor 44 for detecting pressure of intake air toward the ammonia co-firing engine 2, and an intake temperature sensor 45 for detecting temperature of intake air toward the ammonia co-firing engine 2. The control device 9 determines premature ignition of the ammonia co-firing engine 2 or deterioration of exhaust gas properties based on the detection result of the at least one sensor.

[0075] As a result, the engine device 1 can more reliably determine the pre-ignition of the ammonia co-firing engine 2 and the deterioration of the exhaust gas properties, and thus can cope with the pre-ignition and the deterioration of the exhaust gas properties.

[0076] Furthermore, when the control device 9 determines that the ammonia co-firing engine 2 is pre-ignited, the engine device 1 of the present invention reduces the mixing ratio of hydrogen and / or increases the mixing ratio of ammonia in the main fuel.

[0077] With this, the engine device 1 can be controlled so that the output of the ammonia co-firing engine 2 becomes a predetermined target output, and thus the pre-ignition of the ammonia co-firing engine 2 can be suppressed more reliably.

[0078] Furthermore, when the control device 9 determines that the exhaust gas properties of the ammonia co-firing engine 2 have deteriorated, the engine device 1 of the present invention reduces the mixing ratio of hydrogen and / or increases the mixing ratio of ammonia in the main fuel.

[0079] With this, the engine device 1 can be controlled so that the output of the ammonia co-firing engine 2 becomes a predetermined target output, thereby more reliably suppressing deterioration of the exhaust gas properties of the ammonia co-firing engine 2 .

[0080] Furthermore, the engine device 1 of the present invention reforms ammonia by the ammonia decomposition device 13 and the like to generate hydrogen fuel.

[0081] According to this, the engine device 1 does not need to retain a large amount of hydrogen as fuel, and can use the hydrogen generated by reforming ammonia as the main fuel.

[0082] In addition, in the above-mentioned embodiment, although an example is described in which ammonia is introduced from the ammonia tank 11 through the ammonia decomposition device 13 and decomposed and reformed to generate hydrogen fuel, and the gaseous hydrogen is stored in the hydrogen tank 14, the present invention is not limited to this example, and the gaseous hydrogen can also be filled from the outside and stored in the hydrogen tank 14.

[0083] In addition, in the above-mentioned embodiment, although it is described that the engine device 1 has a control device 9 having auxiliary fuel injection information representing at least one of the injection period, injection amount, injection pressure and number of injections of a predetermined hydrocarbon-based fuel, and the control device 9 controls the ignition performed by the ignition device based on the auxiliary fuel injection information, the present invention is not limited to this example.

[0084] In other examples, the engine device 1 is Figure 7As shown, in addition to the configuration of the above-described embodiment, the engine device 1 further includes an intake throttle valve 60, a supercharger 61, an intercooler 62, and a recirculation device 63 (EGR device). Furthermore, the engine device 1 includes an intake bypass passage 64 and a wastegate 65. Furthermore, the engine device 1 includes a rotation sensor 66 for detecting the rotational speed of the ammonia co-firing engine 2.

[0085] Furthermore, the engine device 1 includes: a control device 9 having intake system information, wherein the intake system information represents: an EGR rate of the recirculation device 63, the opening and closing valve timing of the intake valve 31 and the exhaust valve 32 (intake and exhaust valves), the amount of air bypassed from the intake passage 3 to the exhaust passage 4 using the intake bypass passage 64 (i.e., the intake bypass amount), the opening of the exhaust valve 65 of the supercharger 61, and the opening of the variable nozzle 61c of the supercharger 61. The control device 9 is configured to control the excess air ratio of the mixture by controlling at least one of the EGR rate, the opening and closing valve timing of the intake and exhaust valves, the intake bypass amount, the opening of the exhaust valve 65, and the opening of the variable nozzle 61c based on the intake system information.

[0086] Specifically, the engine device 1 is provided with a supercharger 61 , an intercooler 62 , and an intake throttle valve 60 in this order from the upstream side in the intake direction of the intake passage 3 .

[0087] The supercharger 61 includes a turbine 61a and a compressor 61b located in the exhaust passage 4. The turbine 61a is provided with a variable nozzle 61c that adjusts the passage area of ​​the exhaust gas flowing into the turbine 61a. The supercharger 61 rotates the turbine 61a using the exhaust gas flowing through the exhaust passage 4. The rotational force of the turbine 61a drives the compressor 61b, thereby compressing the air flowing through the intake passage 3.

[0088] The recirculation device 63 includes a recirculation passage 63a, a recirculation cooler 63b, and a recirculation valve 63c. The recirculation passage 63a is connected to the exhaust passage 4 upstream of the supercharger 61 (turbine 61a) in the exhaust direction, and is connected to the intake passage 3 downstream of the intercooler 62 in the intake direction. The recirculation device 63 uses the recirculation cooler 63b to cool the exhaust gas flowing through the exhaust passage 4 upstream of the supercharger 61 in the exhaust direction, recirculates the gas, and supplies it to the intake passage 3 downstream of the intercooler 62 in the intake direction. The recirculation device 63 controls the opening of the recirculation valve 63c by the control device 9, thereby adjusting the flow rate of the recirculated exhaust gas flowing into the intake passage 3 and thereby adjusting the oxygen content of the air flowing through the intake passage 3.

[0089] Furthermore, in the engine device 1, an intake bypass passage 64 is provided to connect a position downstream of the supercharger 61 in the intake direction of the intake passage 3 and a position upstream of the supercharger 61 in the exhaust direction of the exhaust passage 4, thereby providing bypass. An intake bypass valve 64a for adjusting the amount of intake bypass is provided in the intake bypass passage 64. In the engine device 1, a wastegate 65 is provided to bypass positions upstream and downstream of the supercharger 61 in the exhaust direction of the exhaust passage 4. A wastegate valve 65a for adjusting the amount of exhaust bypass is provided in the wastegate 65.

[0090] Furthermore, the engine apparatus 1 controls the recirculation valve 63c of the recirculation device 63 via the control device 9 to reduce the proportion of exhaust gas recirculated from the exhaust passage 4 to the intake passage 3 via the recirculation device 63, i.e., the EGR rate. This increases the amount of air in the intake air, thereby increasing the excess air ratio. Alternatively, the EGR rate is increased to reduce the amount of air in the intake air, thereby reducing the excess air ratio. Thus, combustion stability in the combustion chamber 21a is improved by optimizing the excess air ratio relative to the hydrogen mixing ratio.

[0091] Alternatively, the engine apparatus 1 controls the intake valve 31 via the control device 9 to advance the opening timing or retard the closing timing of the intake valve 31, thereby increasing the amount of air in the intake air and thereby increasing the excess air ratio. Alternatively, the engine apparatus 1 controls the intake valve 31 by retarding the opening timing or advancing the closing timing of the intake valve 31, thereby reducing the amount of air in the intake air and thereby reducing the excess air ratio. In this way, combustion stability in the combustion chamber 21a is improved by optimizing the excess air ratio relative to the hydrogen mixing ratio.

[0092] Alternatively, the engine device 1 controls the intake bypass valve 64a via the control device 9 to reduce the intake bypass amount flowing into the exhaust passage 4, thereby increasing the amount of air in the intake air and thus increasing the excess air ratio, or to increase the intake bypass amount, thereby reducing the amount of air in the intake air and thus reducing the excess air ratio. In this way, combustion stability in the combustion chamber 21a is improved by optimizing the excess air ratio relative to the hydrogen mixing ratio.

[0093] Alternatively, the engine device 1 controls the wastegate valve 65a via the control device 9 to reduce the opening of the wastegate 65, thereby increasing the amount of air in the intake air and increasing the excess air ratio, or to increase the opening of the wastegate 65, thereby reducing the amount of air in the intake air and decreasing the excess air ratio. In this way, combustion stability in the combustion chamber 21a is improved by optimizing the excess air ratio relative to the hydrogen mixing ratio.

[0094] Alternatively, the engine device 1 controls the variable nozzle 61c via the control device 9, reducing the opening of the variable nozzle 61c to reduce the passage area of ​​the turbine 61a of the supercharger 61, thereby increasing the amount of air compressed at the supercharger 61, thereby increasing the amount of air in the intake air and increasing the excess air ratio. Alternatively, the engine device 1 controls the variable nozzle 61c via the control device 9 to increase the opening of the variable nozzle 61c to increase the passage area of ​​the turbine 61a of the supercharger 61, thereby reducing the amount of air compressed at the supercharger 61, thereby reducing the amount of air in the intake air and reducing the excess air ratio. In this way, combustion stability in the combustion chamber 21a is improved by optimizing the excess air ratio relative to the hydrogen mixing ratio.

[0095] Thus, according to another example, at least one of the EGR rate, the opening and closing timing of the intake and exhaust valves, the intake bypass amount, the opening of the wastegate 65, and the opening of the variable nozzle 61c is controlled so that the air excess ratio of the mixed gas can be within a predetermined hydrogen mixing ratio. Figure 3 The control is performed in a manner within the range of the stable region 50.

[0096] In addition, in other examples, the engine device 1 is controlled by the control device 9 based on the detection results of at least one sensor among the rotation sensor 66 and the in-cylinder pressure sensor 42, to determine the occurrence of combustion instability of the ammonia co-firing engine 2, or to predict the occurrence of combustion instability of the ammonia co-firing engine 2.

[0097] For example, the control device 9 determines that combustion is unstable when the difference between the target speed of the ammonia mixed combustion engine 2 and the actual speed detected by the rotation sensor 66 exceeds a predetermined difference threshold. In addition, the control device 9 determines that combustion is unstable when the difference between the target pressure in the cylinder 21 (in the combustion chamber 21a) and the actual pressure detected by the cylinder pressure sensor 42 exceeds a predetermined difference threshold.

[0098] Furthermore, when the engine device 1 determines that combustion instability has occurred in the ammonia-burning engine 2, or predicts that combustion instability will occur in the ammonia-burning engine 2, the control device 9 controls the engine 1 so that the hydrogen mixing ratio in the mixed gas is increased (or decreased) and the ammonia mixing ratio is decreased (or increased). In this case, the control device 9 controls the engine 2 so that the output of the ammonia-burning engine 2 reaches a predetermined target output, while adjusting the hydrogen mixing ratio and the ammonia mixing ratio in the mixed gas to suppress combustion instability in the ammonia-burning engine 2.

[0099] Furthermore, the present invention may be appropriately modified without departing from the spirit or concept of the invention as can be read from the claims and the entire contents of the specification, and an ammonia co-firing engine with such modifications is also included in the technical concept of the present invention.

[0100] [Supplementary Notes on the Invention]

[0101] The following is a summary of the invention extracted from the above-mentioned embodiment as a supplementary note. In addition, each configuration and each processing function described in the following supplementary notes can be selected and discarded, and can be combined arbitrarily.

[0102] Note 1

[0103] An engine device is an ammonia co-firing engine that operates by burning a mixture of at least ammonia and hydrogen in a combustion chamber. The engine device is characterized in that the ammonia and hydrogen are supplied to the combustion chamber to generate the mixture, the mixture in the combustion chamber is compressed to increase its temperature and pressure, and the mixture in the combustion chamber is ignited by an ignition device based on the state of the mixture in the combustion chamber.

[0104] Note 2

[0105] In the engine device according to Supplementary Note 1, the ignition device ignites the air-fuel mixture by injecting hydrocarbon fuel or discharging a spark plug.

[0106] Note 3

[0107] Based on the engine device described in Note 1 or 2, it is characterized in that the engine device comprises: a control device having ignition timing information, the ignition timing information representing a predetermined ignition timing based on the relationship between the mixing ratio of the ammonia and the hydrogen and the excess air ratio of the mixture, and the control device controls the ignition of the mixture implemented by the ignition device based on the ignition timing information.

[0108] Note 4

[0109] Based on the engine device described in Appendix 1, it is characterized in that the ignition device is configured to ignite the mixture by injecting a hydrocarbon-based fuel, and the engine device has: a control device having auxiliary fuel injection information, the auxiliary fuel injection information representing at least one of the injection period, injection amount, injection pressure and number of injections of the hydrocarbon-based fuel predetermined based on the relationship between the mixing ratio of the ammonia and the hydrogen and the air excess ratio of the mixture, and the control device controls the ignition performed by the ignition device based on the auxiliary fuel injection information.

[0110] Note 5

[0111] Based on the engine device described in any one of Notes 1 to 4, it is characterized in that the engine device comprises: at least one sensor selected from the group consisting of: a knock sensor for detecting knock of the ammonia co-firing engine, an in-cylinder pressure sensor for detecting pressure in a combustion chamber of the ammonia co-firing engine, an in-cylinder temperature sensor for detecting temperature in a combustion chamber of the ammonia co-firing engine, an intake pressure sensor for detecting pressure of intake air toward the ammonia co-firing engine, and an intake temperature sensor for detecting temperature of intake air toward the ammonia co-firing engine; and based on the detection result of the at least one sensor, it is judged whether the ammonia co-firing engine has premature ignition or whether the exhaust gas properties have deteriorated.

[0112] <Note 6>

[0113] Based on the engine device described in Appendix 5, it is characterized in that when it is determined that the ammonia co-firing engine ignites prematurely, the following steps are performed: reducing the mixing ratio of the hydrogen and / or increasing the mixing ratio of the ammonia.

[0114] <Note 7>

[0115] Based on the engine device described in Appendix 5 or 6, it is characterized in that when it is determined that the exhaust gas properties of the ammonia co-firing engine have deteriorated, the following are performed: reducing the mixing ratio of the hydrogen and / or increasing the mixing ratio of the ammonia.

[0116] <Note 8>

[0117] In the engine device according to any one of Supplementary Notes 1 to 7, the hydrogen gas is generated by reforming the ammonia.

[0118] <Note 9>

[0119] Based on the engine device described in Appendix 1, it is characterized in that the engine device comprises: a control device having intake system information, and the intake system information represents at least one of an EGR rate, a switching valve timing of the intake and exhaust valves, an intake bypass amount, a waste gate opening of the supercharger, and a variable nozzle opening of the supercharger; the control device controls at least one of the EGR rate, the switching valve timing of the intake and exhaust valves, the intake bypass amount, the waste gate opening of the supercharger, and the variable nozzle opening of the supercharger based on the intake system information, thereby controlling the excess air ratio of the mixture.

[0120] <Note 10>

[0121] Based on the engine device described in Note 9, it is characterized in that the engine device includes: a rotation sensor for detecting the rotational speed of the ammonia co-firing engine, and at least one sensor among an in-cylinder pressure sensor for detecting the pressure in the combustion chamber of the ammonia co-firing engine, and based on the detection result of the at least one sensor, the occurrence of combustion instability of the ammonia co-firing engine is judged, or the occurrence of combustion instability of the ammonia co-firing engine is predicted.

[0122] <Note 11> Based on the engine device described in Note 10, it is characterized in that when it is determined that the ammonia co-firing engine has undergone combustion instability, or it is predicted that the ammonia co-firing engine will undergo combustion instability, the mixing ratio of the hydrogen in the mixture is increased and the mixing ratio of the ammonia is reduced.

Claims

1. An engine device, which is an ammonia co-firing engine that operates by burning a mixture of at least ammonia and hydrogen in a combustion chamber, characterized in that: The ammonia and the hydrogen are supplied to the combustion chamber to generate the mixed gas, The mixed gas in the combustion chamber is compressed to increase its temperature and pressure, The air-fuel mixture in the combustion chamber is ignited by an ignition device according to a state of the air-fuel mixture in the combustion chamber.

2. The engine device according to claim 1, characterized in that The ignition device ignites the air-fuel mixture by injecting hydrocarbon-based fuel or discharging with a spark plug.

3. The engine device according to claim 1, characterized in that The engine device includes a control device having ignition timing information indicating a predetermined ignition timing based on a relationship between a mixture ratio of the ammonia and hydrogen gases and an excess air ratio of the mixture gas. The control device controls ignition of the air-fuel mixture by the ignition device based on the ignition timing information.

4. The engine device according to claim 1, characterized in that The ignition device is configured to ignite the air-fuel mixture by injecting a hydrocarbon fuel. The engine device includes a control device having auxiliary fuel injection information indicating at least one of an injection timing, an injection amount, an injection pressure, and a number of injections of the hydrocarbon-based fuel that are predetermined based on a relationship between a mixture ratio of the ammonia and hydrogen gas and an excess air ratio of the mixture gas; The control device controls ignition by the ignition device based on the sub-fuel injection information.

5. The engine device according to claim 1, characterized in that The engine device includes: a knock sensor for detecting knock of the ammonia-burning engine; an in-cylinder pressure sensor for detecting pressure in a combustion chamber of the ammonia-burning engine; an in-cylinder temperature sensor for detecting temperature in the combustion chamber of the ammonia-burning engine; an intake pressure sensor for detecting pressure of intake air to the ammonia-burning engine; and an intake temperature sensor for detecting temperature of intake air to the ammonia-burning engine. Based on the detection result of the at least one sensor, it is determined whether the ammonia co-firing engine has premature ignition or whether the exhaust gas properties have deteriorated.

6. The engine device according to claim 5, characterized in that When it is determined that the ammonia co-firing engine is pre-ignited, the mixing ratio of the hydrogen is reduced and / or the mixing ratio of the ammonia is increased.

7. The engine device according to claim 5, characterized in that When it is determined that the exhaust gas properties of the ammonia co-firing engine have deteriorated, the mixing ratio of the hydrogen gas is reduced and / or the mixing ratio of the ammonia is increased.

8. The engine device according to claim 1, characterized in that The ammonia is reformed to generate the hydrogen.

9. The engine device according to claim 1, characterized in that The engine device includes a control device having intake system information indicating at least one of an EGR rate, an opening and closing timing of an intake and exhaust valve, an intake bypass amount, a wastegate opening of a supercharger, and a variable nozzle opening of the supercharger. The control device controls at least one of the EGR rate, the opening and closing timing of the intake and exhaust valves, the intake bypass amount, the wastegate opening of the supercharger, and the variable nozzle opening of the supercharger based on the intake system information, thereby controlling the excess air ratio of the mixture.

10. The engine device according to claim 9, characterized in that The engine device includes at least one of a rotation sensor for detecting a rotation speed of the ammonia-burning engine and a cylinder pressure sensor for detecting a pressure in a combustion chamber of the ammonia-burning engine. The occurrence of combustion instability in the ammonia co-firing engine is determined or predicted based on the detection result of the at least one sensor.

11. The engine device according to claim 10, characterized in that When it is determined that combustion instability has occurred in the ammonia co-firing engine or it is predicted that combustion instability has occurred in the ammonia co-firing engine, the mixing ratio of the hydrogen gas in the mixture is increased and the mixing ratio of the ammonia is decreased.

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