Engine device

Abstract

To provide an engine device enabling suppression of preignition and stable combustion in an engine driven by heating low GHG fuel with small emissions of greenhouse effect gas such as ammonia and methanol.SOLUTION: An engine device 1 drives an engine 2 by supplying low GHG fuel with small emissions of greenhouse effect gas. The engine device 1 includes a heating section 40 that heats at least one of air mixed with the low GHG fuel and the low GHG fuel. When preignition of the low GHG fuel in the engine 2 is generated or predicted, heating by using the heating section 40 is weakened or stopped.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an engine device that is driven by supplying low GHG (Green House Gas) fuel, such as ammonia or methanol, which emits less greenhouse gases. [Background technology]

[0002] Conventionally, some engine devices are powered by low-GHG fuels with low greenhouse gas emissions, such as ammonia and methanol. The engine device stores the low-GHG fuel in a liquid state and supplies the low-GHG fuel to the combustion chamber by injecting it into the intake path leading to the engine or into the combustion chamber of the engine.

[0003] For example, the ammonia combustion system disclosed in Patent Document 1 mixes ammonia in a liquid state with petroleum-based fuel and injects it. In particular, liquid ammonia or ammonia water is atomized in a fluid mixture and mixed with fuel, and the resulting ammonia- or ammonia-water-mixed fuel is supplied to a diesel engine or boiler. Ammonia injected with petroleum-based fuel into the combustion chamber of a diesel engine or boiler has a boiling point of approximately -33°C under atmospheric pressure, and quickly vaporizes into a flammable gas within the combustion chamber. At that time, the petroleum-based fuel is in the process of ignition and combustion, and because the atmospheric temperature exceeds 1000°C, it easily ignites and burns together with the ammonia. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 7264386 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in conventional engine devices such as that disclosed in Patent Document 1, ammonia easily ignites at high ambient temperatures, making it relatively easy for unexpected ignition to occur in the engine's combustion chamber. When the pressure inside the combustion chamber becomes excessively high due to high-temperature intake air, unexpected ignition of ammonia occurs regardless of the stroke (cycle), causing, for example, pre-ignition, which increases the pressure inside the combustion chamber, potentially damaging the engine and causing unstable combustion.

[0006] The present invention aims to provide an engine device that can suppress pre-ignition and achieve stable combustion in an engine that runs by heating low-GHG fuels with low greenhouse gas emissions, such as ammonia and methanol. [Means for solving the problem]

[0007] In order to solve the above problems, the engine device of the present invention is an engine device that supplies fuel to drive an engine, and is characterized in that it has a heating unit that heats at least one of the air mixed with the fuel and the fuel, and when pre-ignition of the fuel in the engine occurs or is predicted, the heating by the heating unit is weakened or stopped. [Effects of the Invention]

[0008] According to the present invention, an engine device is provided that can suppress pre-ignition and achieve stable combustion in an engine that runs by heating low-GHG fuels with low greenhouse gas emissions, such as ammonia and methanol. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram illustrating an example of an engine device according to an embodiment of the present invention. [Figure 2] FIG. 4 is a schematic diagram illustrating another example of an engine device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] An engine system 1 according to an embodiment of the present invention will be described with reference to the drawings. As shown in Fig. 1, the engine system 1 includes an engine 2, an intake passage 3, an exhaust passage 4, a turbocharger 5, an intercooler 6, a fuel supply mechanism 7, an ignition device 8, and a control unit 9. The engine system 1 also 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.

[0011] Particularly in this embodiment, the engine device 1 is configured to vaporize a low GHG fuel with low greenhouse gas emissions, such as ammonia or methanol, from a liquid state and supply it to the combustion chamber 12a of each cylinder 12 of the engine 2 by a fuel supply unit 35 of the fuel supply mechanism 7. The engine device 1 is configured to burn a mixture of the low GHG fuel and air in the combustion chamber 12a to drive the engine 2.

[0012] The engine 2 is configured with a cylinder block 11 having a plurality of cylinders 12, but Fig. 1 shows only one cylinder 12. As shown in Fig. 1, each cylinder 12 is configured with a cylinder 13, a piston 14, and a cylinder head 15.

[0013] The cylinder 13 is formed, for example, in a cylindrical shape within the cylinder block 11, and the piston 14 is slidably housed within the cylinder 13. The cylinder head 15 is attached to the upper side of the cylinder 13, and the cylinder 13 and the cylinder head 15 form a combustion chamber 12a therein.

[0014] Below the cylinder 13 , a crankshaft 17 is connected to the piston 14 via a connecting rod 16 , and the reciprocating motion of the piston 14 is converted into the rotational motion of the crankshaft 17 via the connecting rod 16 .

[0015] The cylinder head 15 also has an intake port 18 and an exhaust port 19 that communicate with the combustion chamber 12a of the cylinder 13, and is equipped with an intake valve 20 and an exhaust valve 21 that open and close the intake port 18 and the exhaust port 19, respectively, to the combustion chamber 12a.

[0016] The intake port 18 is connected to the intake passage 3 and introduces air supplied from the intake passage 3 into the combustion chamber 12a, while the exhaust port 19 is connected to the exhaust passage 4 and discharges exhaust gas generated in the combustion chamber 12a into the exhaust passage 4. By opening the intake valve 20, a mixture of low GHG fuel and air can be taken into the combustion chamber 12a through the intake port 18, while by opening the exhaust valve 21, exhaust gas generated in the combustion chamber 12a can be exhausted through the exhaust port 19.

[0017] 1 illustrates an example in which an intake manifold 22 having branch passages 22a branching from the intake passage 3 to the plurality of cylinders 12 is provided between the intake passage 3 and the engine 2 to connect the intake passage 3 to the respective intake ports 18 of the plurality of cylinders 12, but alternatively, the intake passage 3 and the intake ports 18 may be directly connected. Also, in FIG. 1 illustrates an example in which an exhaust manifold 23 having branch passages 23a branching from the exhaust passage 4 to the plurality of cylinders 12 is provided between the exhaust passage 4 and the engine 2 to connect the exhaust passage 4 to the respective exhaust ports 19 of the plurality of cylinders 12, but alternatively, the exhaust passage 4 and the exhaust ports 19 may be directly connected.

[0018] The intake passage 3 circulates compressed and cooled air in the intake direction and supplies it to each cylinder 12 of the engine 2 via an intake port 18 of each cylinder 12. The exhaust passage 4 circulates exhaust gas generated in each cylinder 12 of the engine 2 and discharged via an exhaust port 19 in the exhaust direction and discharges it. In the intake passage 3, a supercharger 5 and an intercooler 6 are provided in this order from the upstream side in the intake direction. An air filter (not shown) that purifies and introduces fresh air may be provided at the upstream end of the intake passage 3 in the intake direction.

[0019] The supercharger 5 compresses the air flowing through the intake passage 3 and sends it downstream in the intake direction, and the intercooler 6 cools the air compressed by the supercharger 5.

[0020] The turbocharger 5 has a turbine 5a and a compressor 5b. The turbine 5a is disposed in the exhaust passage 4, and the compressor 5b is disposed in the intake passage 3. The turbine 5a is rotated by the exhaust gas flowing through the exhaust passage 4, and the rotational force of the turbine 5a drives the compressor 5b, thereby compressing the air flowing through the intake passage 3. This increases the pressure of the air to be mixed with the low GHG fuel, and the temperature increases. In other words, the turbocharger 5 functions as a heating unit 40 that heats the air to be mixed with the low GHG fuel by adjusting the rotation speed of the turbocharger 5 (compressor 5b) and / or the pressure of the air discharged from the turbocharger 5.

[0021] The intercooler 6 is a heat exchange unit that circulates a heat exchange medium (cooling water) and uses this heat exchange medium to cool the air passing through the intercooler 6. In other words, the intercooler 6 functions as a heating unit 40 that heats the air to be mixed with the low GHG fuel by adjusting the flow rate and / or flow speed of the heat exchange medium to suppress or stop cooling of the air.

[0022] The fuel supply mechanism 7 supplies low GHG fuel to the combustion chamber 12a of each cylinder 12 of the engine 2. The fuel supply mechanism 7 includes a liquid fuel tank 30, a liquid fuel flow path 31, a vaporization unit 32, a gas fuel flow path 33, and a fuel supply unit 35.

[0023] Liquid fuel tank 30 is a storage unit that stores low GHG fuel in a liquid state. Liquid fuel flow path 31 is connected to liquid fuel tank 30 and vaporizer 32, and low GHG fuel in a liquid state is supplied from liquid fuel tank 30 to vaporizer 32 via liquid fuel flow path 31 by a pump or the like (not shown).

[0024] The vaporization unit 32 vaporizes the low GHG fuel in a liquid state supplied from the liquid fuel tank 30 to the engine 2 by utilizing the exhaust heat from the engine 2. The vaporization unit 32 includes, for example, a vaporizer 36 and a heat exchanger 37.

[0025] The vaporizer 36 is connected to the liquid fuel flow path 31 and the gaseous fuel flow path 33, and vaporizes the low GHG fuel in a liquid state flowing from the liquid fuel flow path 31, and circulates the vaporized low GHG fuel in a gaseous state through the gaseous fuel flow path 33. The heat exchanger 37 circulates a heat exchange medium (cooling medium) and also circulates exhaust gas emitted from the engine 2 or cooling water after heat exchange in the intercooler 6, thereby heating the heat exchange medium using exhaust heat from the engine 2. The heat exchanger 37 then supplies the heated heat exchange medium to the vaporizer 36, and the vaporizer 36 is a heat exchange unit that heats and vaporizes the low GHG fuel in a liquid state using this heat exchange medium.

[0026] That is, vaporizer 36 and heat exchanger 37 function as heating unit 40 that heats the low GHG fuel. Heating unit 40, which is made up of vaporizer 36 and heat exchanger 37, is provided with adjustment valve 37a in a flow path that circulates the heat exchange medium to heat exchanger 37, and adjustment valve 37a makes it possible to adjust the flow rate and / or flow velocity of the heat exchange medium, thereby making it possible to adjust the heating of the low GHG fuel by vaporizer 36.

[0027] The gaseous fuel flow path 33 is connected to the vaporizer 36 and the fuel supply unit 35 , and the low GHG fuel in a gaseous state is supplied from the vaporizer 36 to the fuel supply unit 35 via the gaseous fuel flow path 33 .

[0028] The fuel supply unit 35 has a base end connected to the gaseous fuel flow path 33, and supplies the gaseous low GHG fuel flowing from the gaseous fuel flow path 33 toward the combustion chamber 12a of each cylinder 12 of the engine 2. The fuel supply unit 35 is composed of, for example, a gas admission valve and a gas injector that inject the gaseous fuel. The fuel supply unit 35 has the injection pressure, injection timing, etc. of the gaseous fuel controlled by the control unit 9.

[0029] 1 shows an example in which the fuel supply unit 35 is provided upstream of the intake manifold 22 in the intake direction to supply gaseous low GHG fuel to the intake passage 3. A mixture of air supplied from the intake passage 3 and low GHG fuel supplied from the fuel supply unit 35 is supplied to the combustion chamber 12a of each cylinder 12.

[0030] The fuel supply unit 35 may be provided upstream of the branching to the multiple cylinders 12 in the intake direction to supply the low GHG fuel in a gaseous state to the intake passage 3, or may be provided downstream of the branching to the multiple cylinders 12 to supply the low GHG fuel to the intake passage 3 for each cylinder 12. Alternatively, the fuel supply unit 35 may be provided to supply the low GHG fuel to each branch flow path 22a of the intake manifold 22 in order to supply the low GHG fuel to each cylinder 12, or may be provided to supply the low GHG fuel to each intake port 18, or may be provided to supply the low GHG fuel directly to each combustion chamber 12a.

[0031] An ignition device 8 is provided for each cylinder 12 and ignites the low-GHG fuel in the combustion chamber 12a of each cylinder 12. The ignition device 8 may be configured as a spark ignition type device using an ignition plug, or as a micro-pilot type device that injects a small amount of liquid fuel. Alternatively, the ignition device 8 may be configured as a device that compresses and ignites a mixture of gaseous fuel and liquid fuel. The ignition timing and other parameters of the ignition device 8 are controlled by a control unit 9, and the injection amount and other parameters of the ignition device 8 that is configured to inject liquid fuel are also controlled by the control unit 9.

[0032] The control unit 9 is a computer such as an ECU (Engine Control Unit) that controls the operation of the engine 2, and is equipped with a CPU, ROM, RAM, etc., and is configured to control each part of the engine 2. The control unit 9 may store various programs for controlling the engine 2, and control the engine 2 by reading and executing the programs.

[0033] The knock sensor 41 detects knocking of the engine 2 and is provided, for example, in the cylinder block 11. The knock sensor 41 is connected to the control unit 9 and transmits the detection result to the control unit 9.

[0034] The in-cylinder pressure sensor 42 detects the pressure inside the cylinder 12 (inside the combustion chamber 12a) and is provided, for example, in the cylinder head 15. The in-cylinder pressure sensor 42 is connected to the control unit 9 and transmits the detection result to the control unit 9.

[0035] The in-cylinder temperature sensor 43 detects the temperature inside the cylinder 12 (inside the combustion chamber 12a) and is provided, for example, in the cylinder head 15. The in-cylinder temperature sensor 43 is connected to the control unit 9 and transmits the detection result to the control unit 9.

[0036] The intake pressure sensor 44 detects the pressure of intake air to the engine 2 and is provided, for example, in the intake manifold 22. The intake pressure sensor 44 is connected to the control unit 9 and transmits the detection result to the control unit 9. Note that, in this embodiment, an example is described in which the intake pressure sensor 44 detects the pressure of a mixture of low GHG fuel and air as intake air, but the present invention is not limited to this example, and the intake pressure sensor 44 may detect the pressure of either the low GHG fuel or air as intake air.

[0037] The intake air temperature sensor 45 detects the temperature of intake air to the engine 2, and is provided, for example, in the intake manifold 22. The intake air temperature sensor 45 is connected to the control unit 9 and transmits the detection result to the control unit 9. Note that, in this embodiment, an example is described in which the intake air temperature sensor 45 detects the temperature of a mixture of low GHG fuel and air as intake air, but the present invention is not limited to this example, and the intake air temperature sensor 45 may detect the temperature of either the low GHG fuel or air as intake air.

[0038] Note that Figure 1 illustrates an example in which the engine device 1 is equipped with 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, but the present invention is not limited to this example, and the engine device 1 may be equipped with at least one of these sensors.

[0039] Furthermore, when pre-ignition of low GHG fuel occurs or is predicted in the engine 2, the control unit 9 controls each section to reduce or stop heating by the heating section 40. At this time, the control unit 9 may reduce or stop at least one of heating of air by the turbocharger 5, heating of air by the intercooler 6, and heating of low GHG fuel by the carburetor 36 and the heat exchanger 37. Note that the control unit 9 may control heating by appropriately and selectively controlling the turbocharger 5, the intercooler 6, the carburetor 36, and the heat exchanger 37 according to the temperature of the air or the temperature of the low GHG fuel.

[0040] The control unit 9 determines whether pre-ignition of low GHG fuel in the engine 2 has occurred or is predicted 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 pressure sensor 44, and the intake temperature sensor 45. For example, the control unit 9 may determine that pre-ignition has occurred when abnormal knocking is detected by the knock sensor 41. Alternatively, the control unit 9 may determine that pre-ignition has occurred when 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 12a. Alternatively, the control unit 9 may determine that pre-ignition is predicted when the intake pressure sensor 44 or the intake temperature sensor 45 detects an abnormal increase in pressure or temperature of the intake air supplied to the combustion chamber 12a.

[0041] The control unit 9 then feedback-controls the heating by the heating unit 40 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 pressure sensor 44, and the intake temperature sensor 45. For example, when the control unit 9 determines that pre-ignition has occurred or is predicted based on the detection results of the sensors, it controls each unit to weaken or stop heating by the heating unit 40. On the other hand, when the control unit 9 does not determine that pre-ignition has occurred or is predicted based on the detection results of the sensors, it controls the heating unit 40 to heat the air or the low-GHG fuel so that the low-GHG fuel can be burned stably.

[0042] As described above, according to this embodiment, the engine device 1 is an engine device 1 that drives the engine 2 by supplying low GHG fuel with low greenhouse gas emissions, and includes a heating unit 40 that heats at least one of the low GHG fuel and air mixed with the low GHG fuel, and when pre-ignition of the low GHG fuel in the engine 2 occurs or is predicted, the heating by the heating unit 40 is weakened or stopped. Specifically, the engine device 1 uses ammonia or methanol as the low GHG fuel.

[0043] As a result, in a configuration in which the engine device 1 heats a mixture of low GHG fuel and air to promote combustion of the low GHG fuel in the engine 2, the intake air temperature can be lowered by reducing or stopping the heating of the air or mixture supplied to the engine 2, thereby suppressing unexpected ignition (fire) of the low GHG fuel, for example, pre-ignition. Also, by reducing or stopping the heating of the low GHG fuel, the temperature of the low GHG fuel injected in a gaseous state can be lowered, or the intake air (air) can be cooled by the heat of vaporization of the low GHG fuel injected in a liquid state, thereby lowering the temperature of the mixture.

[0044] Therefore, by supplying the cooled air-fuel mixture to the combustion chamber 12a, the in-cylinder temperature of the combustion chamber 12a is lowered, and it is possible to suppress unexpected ignition (firing) of the low GHG fuel in the combustion chamber 12a, for example, pre-ignition. Therefore, in the engine 2, an increase in the in-cylinder pressure of the combustion chamber 12a due to pre-ignition is suppressed, and damage to the engine 2 is reduced. Furthermore, by suppressing pre-ignition, it is possible to stably burn the low GHG fuel in the combustion chamber 12a. As such, according to the present embodiment, it is possible to provide an engine device 1 that can suppress pre-ignition and achieve stable combustion in the engine 2 that runs by heating low GHG fuel with low greenhouse gas emissions, such as ammonia or methanol.

[0045] Furthermore, according to this embodiment, the engine device 1 is provided with at least one sensor selected from the group consisting of a knock sensor 41 that detects knocking of the engine 2, an in-cylinder pressure sensor 42 that detects the pressure in the combustion chamber 12a of the engine 2, an in-cylinder temperature sensor 43 that detects the temperature in the combustion chamber 12a of the engine 2, an intake pressure sensor 44 that detects the pressure of the intake air to the engine 2, and an intake temperature sensor 45 that detects the temperature of the intake air to the engine 2, and the control unit 9 determines whether pre-ignition of the engine 2 has occurred based on the detection results of the at least one sensor.

[0046] As a result, the engine device 1 can determine the occurrence or prediction of pre-ignition of the engine 2 by a reliable method using a sensor, and can therefore appropriately suppress pre-ignition.

[0047] Furthermore, according to this embodiment, the engine device 1 includes a control unit 9 that feedback controls the heating by the heating section 40 based on the detection result of at least one sensor.

[0048] This allows the engine device 1 to appropriately control the heating by the heating unit 40 by a reliable method using a sensor.

[0049] Furthermore, according to this embodiment, the engine device 1 includes a heat exchange unit such as an intercooler 6 or a carburetor 36 through which at least one of the air to be mixed with the low GHG fuel and the low GHG fuel flows, and the heat exchange unit functions as a heating unit 40 that heats at least one of the air to be mixed with the low GHG fuel and the low GHG fuel by adjusting the flow rate and / or flow speed of the heat exchange medium flowing into the heat exchange unit.

[0050] This allows the engine system 1 to reduce or stop heating of the air or low GHG fuel supplied to the engine 2 by utilizing the existing intercooler 6 or carburetor 36 without having to be equipped with a special heating device.

[0051] Furthermore, according to this embodiment, the engine device 1 is provided with a turbocharger 5 that pressurizes the air to be mixed with the low GHG fuel, and the turbocharger 5 functions as a heating section 40 that heats the air to be mixed with the low GHG fuel by adjusting the rotation speed of the turbocharger 5 and / or the pressure of the air discharged from the turbocharger 5.

[0052] As a result, the engine device 1 can reduce or stop heating of the air and low GHG fuel supplied to the engine 2 by using the existing turbocharger 5 without having to be equipped with a special heating device.

[0053] In the above embodiment, the engine system 1 has been described as having the intercooler 6 and the turbocharger 5 function as the heating unit 40 that heats the air supplied to the engine 2, but the present invention is not limited to this example. In another example, the engine system 1 may configure the heating unit 40 that uses exhaust heat from the engine 2 to heat the air flowing through the intake passage 3, the intake manifold 22, and the intake port 18 by circulating exhaust gas discharged from the engine 2 or cooling water that has undergone heat exchange in the intercooler 6 through the intake passage 3, the intake manifold 22, and the intake port 18.

[0054] In the above embodiment, the engine system 1 has been described as having the carburetor 36 and the heat exchanger 37 function as the heating unit 40 that heats the low GHG fuel, but the present invention is not limited to this example. In another example, the engine system 1 may configure the heating unit 40 to heat the low GHG fuel flowing through the intake passage 3, the intake manifold 22, and the intake port 18 using exhaust heat from the engine 2 by circulating exhaust gas discharged from the engine 2 or cooling water that has undergone heat exchange in the intercooler 6 through the intake passage 3, the intake manifold 22, and the intake port 18.

[0055] In the above embodiment, an example has been described in which the heat exchanger 37 in the vaporization section 32 of the engine device 1 uses waste heat from the engine 2 (for example, exhaust gas emitted from the engine 2 or cooling water after heat exchange in the intercooler 6) to heat the heat exchange medium, and the vaporizer 36 heats the low GHG fuel in liquid state using the heat exchange medium, thereby vaporizing the low GHG fuel by indirectly using the waste heat from the engine 2, but the present invention is not limited to this example. In another example, the vaporization section 32 may be configured not to include the heat exchanger 37, and the vaporizer 36 may be configured to directly use waste heat from the engine 2 to heat and vaporize the low GHG fuel in liquid state.

[0056] Furthermore, in the above-described embodiment, the fuel supply mechanism 7 of the engine device 1 is described as an example in which the low GHG fuel in a liquid state is vaporized by the vaporizer 36, and then the low GHG fuel in a gaseous state is supplied by the fuel supply unit 35 to the combustion chambers 12a of each cylinder 12 of the engine 2, but the present invention is not limited to this example.

[0057] In another example, as shown in FIG. 2, the fuel supply mechanism 7 may be configured not to include a vaporizer 36, but rather the fuel supply unit 35 supplies liquid low GHG fuel toward the combustion chambers 12a of each cylinder 12 of the engine 2, and the vaporization unit 32 may be configured to vaporize the liquid low GHG fuel by utilizing exhaust heat from the engine 2 (for example, exhaust gas discharged from the engine 2 or cooling water after heat exchange in the intercooler 6) downstream in the intake direction from the position where the low GHG fuel is supplied, thereby heating part or all of at least one of the intake passage 3, the intake manifold 22, and the intake port 18.

[0058] For example, the heat exchanger 37 may heat the heat exchange medium by utilizing the exhaust heat from the engine 2, and the vaporizer 32 may use the heat exchange medium to heat the intake passage 3, the intake manifold 22, or the intake port 18, thereby indirectly utilizing the exhaust heat from the engine 2 to vaporize the liquid low GHG fuel. Alternatively, the vaporizer 32 may be configured to vaporize the liquid low GHG fuel by directly utilizing the exhaust heat from the engine 2 to heat the intake passage 3, the intake manifold 22, or the intake port 18, without including the heat exchanger 37.

[0059] In the above embodiment, an example has been described in which the heating unit 40 of the engine device 1 heats the low GHG fuel or the air to be mixed with the low GHG fuel by a configuration (such as the turbocharger 5, intercooler 6, carburetor 36, and heat exchanger 37) that utilizes exhaust heat from the engine 2, but the present invention is not limited to this example. In another example, the heating unit 40 may heat the low GHG fuel or the air by a configuration that utilizes an additional heater that operates on external energy, in addition to or instead of the configuration that utilizes exhaust heat from the engine 2.

[0060] The additional heater is controlled to be turned on or off by the control unit 9. The additional heater may be provided in the liquid fuel passage 31, the gas fuel passage 33, the carburetor 36, the fuel supply unit 35, or in the intake passage 3, the intake manifold 22, or the intake port 18.

[0061] In addition, if the heating section 40 has both a configuration that utilizes exhaust heat from the engine 2 and a configuration that utilizes an additional heater, the control unit 9 may switch between the configuration that utilizes exhaust heat from the engine 2 and the configuration that utilizes the additional heater depending on the operating conditions and operating environment of the engine device 1.

[0062] For example, when the engine 2 is started, the exhaust heat from the engine 2 (for example, the exhaust gas discharged from the engine 2 or the cooling water after heat exchange in the intercooler 6) has not yet reached a temperature at which the low GHG fuel in a liquid state can be sufficiently vaporized, and therefore the control unit 9 performs heating using a configuration that utilizes an additional heater when the engine 2 is started. Note that the control unit 9 may determine that the engine 2 is being started when a predetermined time has elapsed since the engine 2 began to start, or when the exhaust gas discharged from the engine 2 or the cooling water after heat exchange in the intercooler 6 reaches a predetermined temperature. Furthermore, after the engine 2 is started, the control unit 9 performs heating by switching from a configuration that utilizes an additional heater to a configuration that utilizes the exhaust heat from the engine 2.

[0063] Furthermore, the present invention can be modified as appropriate within the scope that does not contradict the gist or idea of ​​the invention that can be read from the claims and the entire specification, and engine devices that involve such modifications are also included in the technical idea of ​​the present invention.

[0064] [Appendix to the invention] The following is a summary of the invention extracted from the above-described embodiment. Note that the configurations and processing functions described in the following supplementary notes can be selected and combined as desired.

[0065] <Appendix 1> An engine device that supplies fuel to drive an engine, a heating unit that heats at least one of the air mixed with the fuel and the fuel, An engine device characterized in that, when pre-ignition of the fuel in the engine occurs or is predicted, heating by the heating unit is weakened or stopped.

[0066] <Appendix 2> at least one sensor selected from a knock sensor that detects knocking of the engine, an in-cylinder pressure sensor that detects the pressure in a combustion chamber of the engine, an in-cylinder temperature sensor that detects the temperature in the combustion chamber of the engine, an intake pressure sensor that detects the pressure of intake air to the engine, and an intake temperature sensor that detects the temperature of intake air to the engine; 2. The engine device according to claim 1, wherein pre-ignition of the engine is determined based on the detection result of the at least one sensor.

[0067] <Appendix 3> 3. The engine device according to claim 2, further comprising a control unit that feedback-controls heating by the heating unit based on a detection result of the at least one sensor.

[0068] <Appendix 4> a heat exchange section through which at least one of the air mixed with the fuel and the fuel flows, The engine device according to any one of appendices 1 to 3, characterized in that the heat exchanger functions as the heating section that heats at least one of the air mixed with the fuel and the fuel by adjusting the flow rate and / or flow velocity of the heat exchange medium flowing into the heat exchanger.

[0069] <Appendix 5> a supercharger that pressurizes air to be mixed with the fuel; 5. The engine device according to claim 1, wherein the turbocharger functions as the heating unit that heats air to be mixed with the fuel by adjusting a rotation speed of the turbocharger and / or a pressure of air discharged from the turbocharger.

[0070] <Appendix 6> 6. The engine device according to any one of claims 1 to 5, wherein the fuel is ammonia or methanol. [Explanation of symbols]

[0071] 1 Engine equipment 2 engines 3 Intake passage 4 Exhaust passage 5. Turbocharger 5a Turbine 5b Compressor 6 Intercooler 7 Fuel supply mechanism 8 Ignition device 9. Control Unit 11 Cylinder block 12 cylinders 12a Combustion chamber 13 cylinders 14 Piston 15 Cylinder head 16 Connecting rod 17. Crankshaft 18 Intake port 19 Exhaust port 20 Intake valve 21 Exhaust valve 22 Intake manifold 22a Branch channel 23 Exhaust manifold 23a Branch channel 30 Liquid fuel tank 31 Liquid fuel flow path 32 Vaporization section 33 gas fuel flow path 35 Fuel supply section 36 Vaporizer 37 Heat exchanger 37a Regulating valve 40 Heating section 41 Knock sensor 42 Cylinder pressure sensor 43 Cylinder temperature sensor 44 Intake pressure sensor 45 Intake air temperature sensor

Claims

1. An engine device that supplies fuel to drive an engine, a heating unit that heats at least one of the air mixed with the fuel and the fuel, An engine device characterized in that, when pre-ignition of the fuel in the engine occurs or is predicted, heating by the heating unit is weakened or stopped.

2. at least one sensor selected from a knock sensor that detects knocking of the engine, an in-cylinder pressure sensor that detects the pressure in a combustion chamber of the engine, an in-cylinder temperature sensor that detects the temperature in the combustion chamber of the engine, an intake pressure sensor that detects the pressure of intake air to the engine, and an intake temperature sensor that detects the temperature of intake air to the engine; 2. The engine device according to claim 1, wherein pre-ignition of the engine is determined based on the detection result of the at least one sensor.

3. 3. The engine device according to claim 2, further comprising a control unit that feedback-controls the heating by the heating section based on the detection result of the at least one sensor.

4. a heat exchange section through which at least one of the air mixed with the fuel and the fuel flows, 2. The engine device according to claim 1, wherein the heat exchanger functions as the heating section that heats at least one of the air mixed with the fuel and the fuel by adjusting the flow rate and / or flow velocity of the heat exchange medium flowing into the heat exchanger.

5. a supercharger that pressurizes air to be mixed with the fuel; 2. The engine device according to claim 1, wherein the turbocharger functions as the heating unit that heats the air to be mixed with the fuel by adjusting a rotation speed of the turbocharger and / or a pressure of the air discharged from the turbocharger.

6. 2. The engine device according to claim 1, wherein the fuel is ammonia or methanol.

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