Ammonia alcohol engine system and fuel supply control method thereof

Abstract

The application provides an ammonia-alcohol engine system and a fuel supply control method thereof. The ammonia-alcohol engine system comprises an engine, an ammonia fuel tank, an alcohol fuel tank, an oil rail and a nozzle. The engine comprises a cylinder, an air inlet channel and an air outlet channel. The cylinder is provided with a combustion chamber. The air inlet channel comprises an air inlet main pipe and an air inlet manifold. The air inlet manifold is connected with the air inlet main pipe. The fuel supply module comprises the ammonia fuel tank, the alcohol fuel tank, the oil rail and the nozzle. The ammonia fuel tank is connected with the alcohol fuel tank through a first pipeline. The alcohol fuel tank is connected with the oil rail through a second pipeline. The nozzle is connected with the oil rail. The air inlet manifold is connected with the cylinder one by one. The ammonia fuel in the ammonia fuel tank is mixed with the alcohol fuel in the alcohol fuel tank through the first pipeline. The ammonia-alcohol mixed fuel is introduced into the oil rail through the second pipeline. The nozzle on the oil rail sprays the ammonia-alcohol mixed fuel into each air inlet manifold or cylinder. The ammonia-alcohol mixed fuel can be sprayed by using a set of nozzles and an oil rail under the premise of ensuring the power demand of the whole vehicle.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of engines, in particular to an ammonia-alcohol engine system and a fuel supply control method thereof. BACKGROUND

[0002] In the field of transportation, to improve engine thermal efficiency and significantly reduce carbon dioxide emissions, using hydrogen, ammonia and other carbon-free fuels for engines is one of the more feasible ways. However, there are many limitations to using ammonia or hydrogen fuel alone in engines. For example, hydrogen has high cost, low safety and low volumetric heat value in terms of production, storage and transportation; ammonia has poor combustion performance and high emissions.

[0003] Due to the high flame speed of alcohol and the high volumetric heat value of liquid injection, the engine power shortage problem caused by ammonia gaseous injection can be compensated for, and the combustion performance of ammonia can be improved. Therefore, in the related art, the combustion performance of ammonia is improved by using ammonia fuel and liquid fuel with high flame speed for companion combustion, such as ammonia and alcohol companion combustion.

[0004] There are two ways to use ammonia fuel in general engines, one is to premix ammonia gas with gaseous fuel such as hydrogen or natural gas, and to inject gaseous fuel, but the volumetric heat value of gaseous fuel is low, which is difficult to meet the power demand of the vehicle; the second is to inject ammonia gas and liquid fuel separately, but this method requires two sets of fuel injection systems, oil rails, gas rails and two sets of nozzles, which are difficult to arrange on the cylinder head.

[0005] That is, the utilization of ammonia fuel in existing engines has high limitations. SUMMARY

[0006] The present application provides an ammonia-alcohol engine system, which realizes the injection of ammonia-alcohol fuel by using one set of nozzles and one oil rail under the premise of meeting the power demand of the vehicle.

[0007] The present application also provides a fuel supply control method for an ammonia-alcohol engine system.

[0008] The present application provides an ammonia-alcohol engine system, comprising:

[0009] An engine, comprising a cylinder, an intake port and an exhaust port, a combustion chamber is formed in the cylinder, the intake port comprises an intake main pipe and an intake manifold, the intake manifold is connected with the intake main pipe;

[0010] A fuel supply module, comprising an ammonia fuel tank, an alcohol fuel tank, an oil rail and a nozzle, the ammonia fuel tank is connected with the alcohol fuel tank through a first pipeline, the alcohol fuel tank is connected with the oil rail through a second pipeline, and the nozzle is connected with the oil rail;

[0011] The intake manifold is connected with the cylinder one by one.

[0012] According to the ammonia alcohol engine system provided by the application, the first pipeline is provided with a pressure reducing valve.

[0013] According to the ammonia alcohol engine system provided by the application, the second pipeline is provided with an oil pump.

[0014] According to the ammonia alcohol engine system provided by the application, the inlet end of the first pipeline is arranged at the upper part of the inner cavity of the ammonia fuel tank, the outlet end of the first pipeline is arranged at the upper part of the inner cavity of the alcohol fuel tank, and the inlet end of the second pipeline is arranged at the lower part of the inner cavity of the alcohol fuel tank.

[0015] According to the ammonia alcohol engine system provided by the application, the nozzles are arranged in the intake manifold one by one; or the nozzles are arranged in the combustion chamber one by one.

[0016] According to the ammonia alcohol engine system provided by the application, the system further comprises a heat management system, the heat management system comprises a heat exchanger and a cooling water tank, the heat exchanger is connected with the cooling water tank through a pipeline, and the heat exchanger is used for heat exchange with ammonia fuel in the ammonia fuel tank.

[0017] According to the ammonia alcohol engine system provided by the application, the heat management system further comprises a thermostat, and the thermostat is connected with the heat exchanger and the cooling water tank through pipelines respectively.

[0018] According to the ammonia alcohol engine system provided by the application, the system further comprises an aftertreatment module, the aftertreatment module is connected with the exhaust passage, and the aftertreatment module is used for treating engine exhaust.

[0019] The application further provides a fuel supply control method based on the ammonia alcohol engine system according to any one of the above.

[0020] An engine cooling water temperature setting value T0 and an engine effective average pressure setting value P0 are preset.

[0021] An engine cooling water temperature signal T1 is acquired, and an engine effective average pressure value P1 is determined.

[0022] T1 is compared with T0, P1 is compared with P0, and the opening and closing of the pressure reducing valve and the oil pump are controlled according to the comparison results.

[0023] The fuel supply control method of the ammonia alcohol engine system provided by the application, the method for controlling the opening and closing of the pressure reducing valve and the oil pump according to the comparison results comprises the following steps.

[0024] When T1 is less than or equal to T0 or P1 is less than or equal to P0, the pressure reducing valve is closed, the oil pump is powered and pressurized, and the nozzles spray oil.

[0025] When T1 is greater than T0 and P1 is greater than P0, the pressure reducing valve is opened, the oil pump is powered off, and the nozzle sprays oil.

[0026] The ammonia-alcohol engine system provided by the application can realize the injection of ammonia / alcohol fuel by using a set of nozzles and an oil rail under the premise of guaranteeing the power demand of the vehicle.

[0027] The fuel supply control method of the ammonia-alcohol engine system provided by the application can automatically control the mixing ratio of ammonia and alcohol in the mixed fuel and adjust the injection mode of the nozzle by comparing the obtained engine cooling water temperature signal and the determined engine effective average pressure value with the preset engine cooling water temperature setting value and engine effective average pressure setting value respectively and controlling the opening and closing of the pressure reducing valve and the oil pump according to the comparison result.

[0028] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following description and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0030] Figure 1 is a schematic diagram of an embodiment of the ammonia-alcohol engine system provided by the application (the heat management system is hidden);

[0031] Figure 2 is a schematic diagram of an embodiment of the heat management system in the ammonia-alcohol engine system provided by the application;

[0032] Figure 3 is a schematic diagram of an embodiment of the fuel supply control method of the ammonia-alcohol engine system provided by the application.

[0033] REFERENCE SIGNS:

[0034] 1, engine; 101, cylinder; 102, intake passage; 1021, intake main pipe; 1022, intake manifold; 103, exhaust passage; 2, ammonia fuel tank; 3, alcohol fuel tank; 4, oil rail; 5, nozzle; 6, first pipeline; 7, second pipeline; 8, pressure reducing valve; 9, oil pump; 10, heat exchanger; 11, cooling water tank; 12, thermostat; 13, water pump; 14, aftertreatment module. DETAILED DESCRIPTION

[0035] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below with reference to the drawings in the present application. Obviously, the described embodiments are only part of, rather than all of, the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of the present application.

[0036] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the present application. Figures 1-3 The present application provides an ammonia-alcohol engine system and a fuel supply control method thereof.

[0037] As shown in FIG. 1, it is a schematic diagram of an embodiment of the ammonia-alcohol engine system provided by the present application. The ammonia-alcohol engine system in the embodiment comprises: Figure 1 An engine 1, the engine 1 comprises a cylinder 101, an intake passage 102 and an exhaust passage 103, the cylinder 101 forms a combustion chamber, wherein the piston top, the cylinder wall, the cylinder cover, the valve, the spark plug and the like jointly form the combustion chamber, the intake passage 102 comprises an intake main pipe 1021 and an intake manifold 1022, the intake manifold 1022 is connected with the intake main pipe 1021. The compression ratio of the engine 1 is greater than or equal to 15, and the ignition energy of the spark plug is greater than or equal to 90 mJ;

[0038] A fuel supply module, the fuel supply module comprises an ammonia fuel tank 2, an alcohol fuel tank 3, an oil rail 4 and a nozzle 5, the ammonia fuel tank 2 is connected with the alcohol fuel tank 3 through a first pipeline 6, the alcohol fuel tank 3 is connected with the oil rail 4 through a second pipeline 7, and the nozzle 5 is connected with the oil rail 4. In the embodiment, the number of the nozzle 5 corresponds to the number of the cylinder 101 one by one.

[0039] The intake manifold 1022 is connected with the cylinder 101 one by one.

[0040] In addition, in order to realize the state switching of the intake manifold 1022 and the exhaust passage 103, in the embodiment, the intake manifold 1022 and the exhaust passage 103 are respectively provided with valves between the intake manifold 1022 and the exhaust passage 103 and the cylinder 101. By setting the valves, the connection state between the intake manifold 1022 and the exhaust passage 103 and the cylinder 101 can be switched between the on state and the off state. The mixture of the ammonia-alcohol mixed fuel and the air enters the cylinder 101 from the intake manifold 1022 through the valve, and the spark plug (not shown in the figure) jumps to ignite the combustible mixture in the cylinder 101, thereby driving the piston to work.

[0041]

[0042] ​It should be noted that the number of cylinders 101 can be one or more, and the number of nozzles 5 and intake manifolds 1022 is one-to-one corresponding to the number of cylinders 101. In the embodiment, the number of cylinders 101 is taken as an example of four.

[0043] The ammonia fuel in the ammonia fuel tank 2 is introduced into the alcohol fuel tank 3 through the first pipeline 6 to mix with the alcohol fuel, and then the ammonia-alcohol mixed fuel is introduced into the oil rail 4 through the second pipeline 7. The nozzles 5 on the oil rail 4 spray the ammonia-alcohol mixed fuel into each intake manifold 1022 or cylinder 101, which can realize the injection of ammonia-alcohol mixed fuel using a set of nozzles 5 and an oil rail 4 under the premise of ensuring the power demand of the vehicle.

[0044] As shown in Figure 1 In the embodiment, a pressure reducing valve 8 is arranged on the first pipeline 6. By adjusting the opening of the pressure reducing valve 8, the pressure of the ammonia gas leaving the ammonia fuel tank 2 through the first pipeline 6 can be adjusted, thereby adjusting the amount of ammonia gas dissolved in the alcohol fuel and realizing the adjustment of the ammonia-alcohol ratio in the mixed fuel.

[0045] As shown in Figure 1 In the embodiment, an oil pump 9 is arranged on the second pipeline 7. The pressure of the mixed fuel in the second pipeline 7 can be adjusted by the oil pump 9. In the case that high-pressure ammonia gas is not introduced into the alcohol fuel tank 3, the fuel in the alcohol fuel tank 3 can be pressurized by the oil pump 9 and then introduced into the oil rail 4. In the embodiment, the oil pump 9 is in a constant-on state without power supply. In some embodiments, if the oil pump 9 is in a constant-off state without power supply, the oil rail 4 is connected to two pipelines, one of which is the second pipeline 7, and the other pipeline is directly connected to the alcohol fuel tank 3 without passing through the oil pump 9. The inlet end of this pipeline is also located at the lower part of the inner cavity of the alcohol fuel tank 3, and a valve is arranged on the pipeline to control the opening and closing of the pipeline.

[0046] As shown in Figure 1As shown, in the embodiment, the inlet end of the first pipeline 6 is arranged at the upper portion of the inner cavity of the ammonia fuel tank 2, the outlet end of the first pipeline 6 is arranged at the upper portion of the inner cavity of the alcohol fuel tank 3, and the inlet end of the second pipeline 7 is arranged at the lower portion of the inner cavity of the alcohol fuel tank 3. In the case that the ammonia fuel tank 2 and the alcohol fuel tank 3 are respectively filled with ammonia fuel and alcohol fuel, the inlet end and the outlet end of the first pipeline 6 can be arranged above the fuel liquid level, and the inlet end of the second pipeline 7 can be arranged below the fuel liquid level. In this way, in the specific implementation, since a certain pressure needs to be established in the oil rail 4 for fuel injection, the pressure in the oil rail 4 can be established by the high-pressure ammonia gas in the alcohol fuel tank 3, the upper portion of the inner cavity of the alcohol fuel tank 3 is filled with high-pressure ammonia gas, the liquid level of the fuel in the inner cavity of the alcohol fuel tank 3 is pressed, and thus the fuel at a certain pressure enters the oil rail 4 through the second pipeline 7. Obviously, in the case that the high-pressure ammonia gas is not introduced into the alcohol fuel tank 3, the fuel in the alcohol fuel tank 3 can enter the oil rail 4 after being pressurized by the oil pump 9.

[0047] In the embodiment, the nozzle 5 can be arranged in the following two ways:

[0048] Way one: the nozzle 5 is arranged one by one in the intake manifold 1022, and at this time, the injection mode is intake port injection;

[0049] Way two: the nozzle 5 is arranged one by one in the combustion chamber, and at this time, the injection mode is direct injection into the cylinder, the oil pump 9 needs to be a high-pressure oil pump, and the oil pump 9 is always in the working state when the engine 1 is working.

[0050] As shown in Figure 1 and Figure 2 As shown, in the embodiment, the ammonia-alcohol engine system further comprises a thermal management system, the thermal management system comprises a heat exchanger 10 and a cooling water tank 11, the heat exchanger 10 and the cooling water tank 11 are connected through a pipeline, and the heat exchanger 10 is used for heat exchange with the ammonia fuel in the ammonia fuel tank 2. In the embodiment, the heat exchanger 10 is arranged on the outer wall of the ammonia fuel tank 2, so as to facilitate heat exchange with the ammonia fuel in the ammonia fuel tank 2. The ammonia fuel in the ammonia fuel tank 2 can be heated through the heat exchanger 10, so as to promote the gasification of the liquid ammonia, thereby ensuring the supply amount of the ammonia fuel.

[0051] As shown in Figure 2As shown, in the embodiment, the heat management system further comprises a thermostat 12, which is connected with the heat exchanger 10 and the cooling water tank 11 through pipes, and a water pump 13 is arranged on the pipe connected with the cooling water tank 11, for driving the cooling water to flow. According to the control strategy of the engine 1, when the main valve of the thermostat 12 is opened, the cooling water of the engine 1 flows through the heat exchanger 10 outside the ammonia fuel tank 2 and then flows into the cooling water tank 11, so as to heat the liquid ammonia and accelerate the gasification speed of the liquid ammonia, thereby ensuring the supply of the ammonia fuel; when the main valve of the thermostat 12 is closed, the cooling water of the engine 1 does not flow through the heat exchanger 10 outside the ammonia fuel tank 2 and the cooling water tank 11, so as to reduce the heat dissipation and ensure the thermal engine speed of the engine. The control strategy of the thermostat 12 is the same as that of the general engine 1.

[0052] As shown in the figure, Figure 1 As shown, in the embodiment, the ammonia-alcohol engine system further comprises an aftertreatment module 14, which is connected with the exhaust passage 103, and the aftertreatment module 14 is used for treating the exhaust gas of the engine 1 (including harmful pollutants such as nitrogen oxides, unburned hydrocarbons, unburned ammonia and carbon monoxide). When the engine 1 is in stoichiometric combustion, the aftertreatment module 14 comprises an oxygen sensor and a three-way catalytic converter; if the engine 1 is in lean combustion, the aftertreatment module 14 comprises an oxidation catalytic converter, a selective catalytic reducer and an ammonia selective oxidizer.

[0053] In addition, the ammonia-alcohol engine system of the embodiment further comprises a controller, i.e. an electronic control unit, which is signal-connected with the spark plug, the nozzle 5, the oxygen sensor, the pressure reducing valve 8 and other sensors and actuators necessary for the engine 1, for monitoring the running state of the engine 1 and issuing corresponding control instructions.

[0054] It should be noted that, in the present application, the alcohol fuel mainly refers to methanol, ethanol or mixed fuel thereof, and other liquid alcohols or liquid mixed fuel thereof can also be used without creative labor, and the alcohol fuel can also be replaced by gasoline fuel.

[0055] As can be known from the above description of the embodiment, the ammonia-alcohol engine system provided by the present application has the following advantages: the ammonia is burned together with the alcohol, the chemical inertness of the ammonia can limit the easy early combustion characteristics of the methanol and other fuels, and the occurrence of super knock and damage to the engine 1 can be prevented; and the high flame speed characteristics of the methanol, ethanol and other fuels can improve the combustion performance of the ammonia. Embodiment 2

[0056] The present application also provides a fuel supply control method based on the ammonia-alcohol engine system as in Embodiment 1, comprising:

[0057] A preset engine 1 cooling water temperature set value T0, a preset engine 1 effective average pressure set value P0, it needs to be explained that the values of T0 and P0 can be fixed values, or values that fluctuate up and down according to actual conditions, or a range containing an upper limit and a lower limit (producing a hysteresis effect to make the output signal more stable). In this embodiment, T0 is 70℃ and P0 is 0.5 MPa.

[0058] An engine 1 cooling water temperature signal T1 is obtained, and an engine 1 effective average pressure value P1 is determined.

[0059] T1 is compared with T0 (70℃), and P1 is compared with P0 (0.5 MPa), and the opening and closing of the pressure reducing valve 8 and the oil pump 9 are controlled according to the comparison results.

[0060] Specifically, the method for controlling the opening and closing of the pressure reducing valve 8 and the oil pump 9 according to the comparison results comprises:

[0061] When T1 is less than or equal to T0 (70℃) or P1 is less than or equal to P0 (0.5 MPa), the controller issues an instruction to close the pressure reducing valve 8, the controller issues an instruction to connect the power supply of the oil pump 9, the fuel in the alcohol fuel tank 3 is pressurized by the oil pump 9 and then enters the oil rail 4, and the nozzle 5 sprays oil.

[0062] When T1 is greater than T0 (70℃) and P1 is greater than P0 (0.5 MPa), the controller issues an instruction to open the pressure reducing valve 8, the controller issues an instruction to disconnect the power supply of the oil pump 9, the high-pressure ammonia gas in the upper part of the inner cavity of the alcohol fuel tank 3 extrudes the liquid surface, the high-pressure fuel in the second pipeline 7 directly enters the oil rail 4, and the nozzle 5 sprays oil.

[0063] In addition, the controller can also issue a control instruction to the nozzle 5 according to the working condition of the engine 1, so that the fuel sprayed by the nozzle 5 mixes with air in the intake manifold 1022 and enters the cylinder 101.

[0064] The fuel supply control method of the ammonia alcohol engine system provided by the present application can automatically control the mixing ratio of ammonia alcohol in the mixed fuel and adjust the injection mode of the nozzle 5 by comparing the obtained engine 1 cooling water temperature signal and the determined engine 1 effective average pressure value with the preset engine 1 cooling water temperature set value and the engine 1 effective average pressure set value, respectively, and controlling the opening and closing of the pressure reducing valve 8 and the oil pump 9 according to the comparison results.

[0065] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An ammonia alcohol engine system characterized by, The application relates to an ammonia-alcohol-oil engine, which comprises the following parts: an engine, which comprises a cylinder, an air inlet channel and an air outlet channel, a combustion chamber is formed in the cylinder, the air inlet channel comprises an air inlet main pipe and an air inlet manifold, and the air inlet manifold is connected with the air inlet main pipe; a fuel supply module, which comprises an ammonia fuel tank, an alcohol fuel tank, an oil rail and a nozzle, the ammonia fuel tank is connected with the alcohol fuel tank through a first pipeline, the alcohol fuel tank is connected with the oil rail through a second pipeline, and the nozzle is connected with the oil rail; the air inlet manifold is connected with the cylinder one by one; a heat management system, which comprises a heat exchanger and a cooling water tank, the heat exchanger is connected with the cooling water tank through a pipeline, and the heat exchanger is used for heat exchange with ammonia fuel in the ammonia fuel tank; the heat management system further comprises a thermostat, and the thermostat is connected with the heat exchanger and the cooling water tank through pipelines respectively; an inlet end of the first pipeline is arranged at an upper portion of an inner cavity of the ammonia fuel tank, an outlet end of the first pipeline is arranged at an upper portion of an inner cavity of the alcohol fuel tank, and an inlet end of the second pipeline is arranged at a lower portion of an inner cavity of the alcohol fuel tank.

2. The ammonia alcohol engine system of claim 1, wherein, A pressure reducing valve is arranged on the first pipeline.

3. The ammonia alcohol engine system of claim 1, wherein, An oil pump is arranged on the second pipeline.

4. The ammonia alcohol engine system of claim 1, wherein, The nozzle is arranged in the air inlet manifold one by one; or the nozzle is arranged in the combustion chamber one by one.

5. The ammonia alcohol engine system according to any one of claims 1 to 4, characterized by, a post-processing module, which is connected with the air outlet channel and is used for processing engine tail gas.

6. A fuel supply control method based on the ammonia alcohol engine system according to any one of claims 1 to 5, characterized by The application further relates to a method for controlling an ammonia-alcohol-oil engine, which comprises the following steps: presetting an engine cooling water temperature setting value T0 and an engine effective average pressure setting value P0; acquiring an engine cooling water temperature signal T1 and determining an engine effective average pressure value P1; comparing T1 with T0 and comparing P1 with P0, and controlling opening and closing of a pressure reducing valve and an oil pump according to a comparison result.

7. The fuel supply control method of an ammonia alcohol engine system according to claim 6, characterized by The method for controlling opening and closing of the pressure reducing valve and the oil pump according to the comparison result comprises the following steps: when T1 is less than or equal to T0 or P1 is less than or equal to P0, the pressure reducing valve is closed, the oil pump is electrified and pressurized, and the nozzle sprays oil; when T1 is greater than T0 and P1 is greater than P0, the pressure reducing valve is opened, the oil pump is de-energized, and the nozzle sprays oil.

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