In-cylinder reforming methanol engine control method and methanol engine

Abstract

The invention provides an in-cylinder reforming methanol engine control method which comprises the following steps: acquiring the rotating speed of an engine and the opening information of an accelerator pedal, and judging the operation condition of the engine; adjusting the mixing ratio of the reforming cycle gas quantity to the gas inlet quantity according to the operation condition; and the air inlet temperature of the engine is obtained, and the fuel injection quantity in the reforming process is adjusted according to the air inlet temperature.

Description

Technical Field

[0001] This disclosure relates to the field of engine and engine control technology, and more specifically, to an in-cylinder reforming methanol engine control method and a methanol engine. Background Technology

[0002] With the increasing severity of the energy crisis and environmental pollution, the search for clean and renewable alternative fuels has become a research hotspot in the field of internal combustion engines. Methanol, as an oxygenated fuel, boasts advantages such as wide availability, mature production processes, and clean combustion, and is considered one of the most promising alternative fuels for internal combustion engines. Compression-ignition engines, with their high thermal efficiency and good fuel economy, are widely used in transportation, construction machinery, and other fields. Applying methanol to compression-ignition engines can effectively reduce carbon and pollutant emissions, which is of great significance for achieving energy conservation and emission reduction in internal combustion engines. However, as a fuel with a low boiling point and low cetane number, methanol faces some technical challenges in its application in compression-ignition engines, such as difficulties in compression ignition and cold starts, its corrosiveness to some metals and rubbers, and its potential solubility in lubricating oils, affecting lubrication performance.

[0003] Fuel reforming technology refers to the process of converting hydrocarbon fuels (such as natural gas, gasoline, diesel, methanol, etc.) into syngas rich in hydrogen (H2) and carbon monoxide (CO) through chemical reactions. This technology has broad application prospects in chemical engineering, energy, and environmental protection, such as hydrogen source preparation for fuel cells, synthesis of liquid fuels, and reduction of internal combustion engine emissions. Methanol, with its advantages of convenient storage and transportation, high energy density, and high hydrogen content (12.6 wt%), is considered one of the ideal hydrogen carriers. Methanol reforming technology offers advantages such as low reaction temperature (200-350℃), high hydrogen yield, and controllable CO selectivity.

[0004] Methanol reforming is mainly divided into external reforming and internal reforming. The main advantage of internal reforming is that it can be implemented through the engine's own structure, eliminating the need for an external fuel reformer and simplifying system modification. Therefore, recirculating the reformed gas back into the cylinder for combustion improves fuel efficiency and reduces emissions in compression-ignition methanol engines. However, the required air-fuel mixture ratio varies under different operating conditions, and the presence of reformed gas reduces ignition stability. Therefore, providing a control method that enables methanol engines to achieve stable ignition under various operating conditions based on fuel reforming and recirculation has become a pressing technical problem. Summary of the Invention

[0005] In view of this, the present disclosure provides an in-cylinder reforming methanol engine control method that can adapt to different operating conditions and different intake air temperatures, thereby improving the ignition stability of the methanol engine.

[0006] To achieve the above objectives, this disclosure provides an in-cylinder reforming methanol engine control method, including acquiring engine speed and throttle pedal opening information to determine engine operating conditions; adjusting the mixing ratio of reforming gas volume and intake air volume according to the above operating conditions; acquiring engine intake air temperature; and adjusting the fuel injection volume during the reforming process according to the above intake air temperature.

[0007] According to embodiments of this disclosure, when the engine speed is less than a preset speed, it is determined to be a cold start condition; when the engine speed is greater than the preset speed and the accelerator pedal opening is less than 20%, it is determined to be a low load condition; when the engine speed is greater than the preset speed and the accelerator pedal opening is between 20% and 70%, it is determined to be a medium load condition; and when the engine speed is greater than the preset speed and the accelerator pedal opening is greater than 70%, it is determined to be a high load condition.

[0008] According to embodiments of this disclosure, under the aforementioned cold start condition, the ratio of the reforming gas volume to the intake gas volume is adjusted to 3:7; under the aforementioned low load condition, the ratio of the reforming gas volume to the intake gas volume is adjusted to 1:3; and under the aforementioned medium load condition, the ratio of the reforming gas volume to the intake gas volume is adjusted to 1:4.

[0009] According to embodiments of this disclosure, adjusting the ratio of the reforming gas volume to the intake gas volume to 1:3 under low-load conditions further includes: when the intake air temperature is less than or equal to 0°C, adjusting the fuel injection volume during the reforming process to 1.25 times the preset fuel injection volume; when the intake air temperature is greater than 0°C and less than 30°C, adjusting the fuel injection volume during the reforming process to 1.2 times the preset fuel injection volume; and when the intake air temperature is greater than or equal to 30°C, adjusting the fuel injection volume during the reforming process to 1.1 times the preset fuel injection volume.

[0010] According to an embodiment of this disclosure, under medium load conditions, adjusting the ratio of the reforming gas volume to the intake gas volume to 1:4 further includes: when the intake air temperature is less than or equal to 25°C, adjusting the fuel injection volume during the reforming process to 1.2 times the preset fuel injection volume; when the intake air temperature is greater than 25°C, adjusting the fuel injection volume during the reforming process to 1.1 times the preset fuel injection volume.

[0011] According to an embodiment of this disclosure, under the above-mentioned high-load operating conditions and when the intake air temperature is less than or equal to 20°C, the ratio of the reforming gas volume to the intake air volume is adjusted to 3:13, and the fuel injection volume during the reforming process is adjusted to 1.1 times the preset fuel injection volume.

[0012] According to embodiments of this disclosure, under the aforementioned high-load conditions and when the intake air temperature is greater than 20°C, the reforming reaction is stopped and the reformed gas circulation is no longer carried out.

[0013] This disclosure also provides a methanol engine controlled using the control method of any of the above embodiments, comprising: a cylinder block having a reforming chamber and a plurality of working chambers formed therein; an intake section configured to supply air to the reforming chamber and the working chambers to form a methanol mixture with methanol fuel; wherein the reforming chamber is adapted to allow the methanol mixture to undergo a reforming reaction to generate reformed gas; the intake section is further configured to supply the reformed gas in the reforming chamber to the working chambers, and is configured to adjust the supply amount in response to at least one of engine speed, throttle pedal opening, and intake air temperature.

[0014] According to an embodiment of this disclosure, the air intake section includes: an air intake pipe having a first inlet and a plurality of first outlets, the first inlet being in communication with the external environment, and the plurality of first outlets being respectively connected to the reforming chamber and the working chamber to guide air in and form the methanol mixture; a circulation pipe having a second inlet and a plurality of second outlets, the second inlet being connected to the reforming chamber, and the second outlets being connected to the working chamber to guide the reformed circulating gas into the working chamber; and a regulating valve, the first outlets and the second outlets being connected to the working chamber through the regulating valve, suitable for regulating the ratio between the methanol mixture and the reformed circulating gas entering the working chamber.

[0015] According to embodiments of this disclosure, the system further includes a plurality of pistons, each piston top defining the reforming chamber or the working chamber within the cylinder body.

[0016] The in-cylinder reforming methanol engine control method and methanol engine disclosed herein improve ignition stability by adjusting the mixing ratio of reforming gas and intake air to adapt to different combustion conditions. Furthermore, it is necessary to obtain the engine's intake air temperature. Based on the determined operating conditions, the reforming fuel injection quantity is adjusted according to the intake air temperature to adjust the amount of reforming gas produced. This, combined with the adjustment of the mixing ratio, ensures stable ignition of the methanol engine under different operating conditions and intake air temperatures. Attached Figure Description

[0017] The above and other objects, features and advantages of this disclosure will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0018] Figure 1 This is a flowchart of the control method for an in-cylinder reforming methanol engine provided in this disclosure;

[0019] Figure 2 yes Figure 1 A schematic diagram of the control logic in the exemplary embodiment shown;

[0020] Figure 3This is a schematic diagram of the working principle of the methanol engine provided in this disclosure;

[0021] Figure 4 This is a schematic diagram of the working principle of a methanol engine provided in another embodiment of this disclosure.

[0022] In the accompanying drawings, the meanings of the reference numerals are as follows:

[0023] 1. Cylinder block;

[0024] 11. Realigning the cavity;

[0025] 12. Working chamber;

[0026] 2. Air intake section;

[0027] 21. Intake pipe;

[0028] 22. Circulation piping;

[0029] 23. Control valve;

[0030] 3. Piston;

[0031] 4. Fuel injectors;

[0032] 5. Exhaust section;

[0033] 51. Exhaust pipe;

[0034] 52. Valves;

[0035] 6. Intake valve;

[0036] 7. Exhaust valve. Detailed Implementation

[0037] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0038] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0039] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0040] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0041] Figure 1 This is a flowchart of the control method for an in-cylinder reforming methanol engine provided in this disclosure. Figure 2 yes Figure 1 The illustrated exemplary embodiment shows a control logic diagram.

[0042] An exemplary embodiment of this disclosure provides a control method for an in-cylinder reforming methanol engine, such as... Figure 1 As shown, it includes the following steps S100-S300.

[0043] Step S100: Obtain engine speed and accelerator pedal opening information to determine engine operating conditions.

[0044] Step S200: Adjust the mixing ratio of reforming gas volume and intake gas volume according to the operating conditions.

[0045] Step S300: Obtain the engine intake air temperature and adjust the fuel injection quantity during the reforming process based on the intake air temperature.

[0046] In this implementation, the engine's operating condition is first determined by comprehensively analyzing engine speed and throttle pedal opening. The mixing ratio of reformed gas and intake air is then adjusted accordingly. Specifically, in a multi-cylinder methanol engine, at least one cylinder is used for methanol fuel reforming. The reformed gas is then circulated to other cylinders to mix and burn with methanol and air. During this process, the mixing ratio of reformed gas and intake air is adjusted to adapt to different combustion conditions and improve ignition stability. Furthermore, the engine's intake air temperature is obtained. Based on the determined operating conditions, the reformed fuel injection quantity is adjusted according to the intake air temperature to regulate the amount of reformed gas produced. This, combined with the adjustment of the mixing ratio, ensures stable ignition of the methanol engine under different operating conditions and intake air temperatures.

[0047] In one exemplary embodiment, such as Figure 2As shown, when the engine speed is lower than the preset speed, it is determined to be a cold start condition. When the engine speed is higher than the preset speed and the accelerator pedal opening is less than 20%, it is determined to be a low load condition. When the engine speed is higher than the preset speed and the accelerator pedal opening is between 20% and 70%, it is determined to be a medium load condition. When the engine speed is higher than the preset speed and the accelerator pedal opening is greater than 70%, it is determined to be a high load condition.

[0048] In some embodiments, the preset rotation speed is set within the range of 500-1500 rpm.

[0049] In this implementation, taking a preset engine speed of 1500 rpm as an example, when the engine speed is less than 1500 rpm, the accelerator pedal opening is usually less than 10%, which is a cold start condition. At this time, the engine has a certain load requirement to improve starting conditions. When the engine speed is greater than 1500 rpm and the accelerator pedal opening is less than 20%, it is a low load condition, which is usually for city driving. The engine intake air volume is small, the combustion efficiency is low, and the fuel consumption is slightly higher. When the engine speed is greater than 1500 rpm and the accelerator pedal opening is between 20% and 70%, it is a medium load condition, which is usually for cruising. The combustion efficiency is high and the operation is smooth. When the engine speed is greater than 1500 rpm and the accelerator pedal opening is greater than 70%, it is a high load condition, which is usually for acceleration, climbing, or heavy load conditions. At this time, the intake air volume and fuel injection volume are both higher, and the emissions are correspondingly higher.

[0050] According to embodiments of this disclosure, under cold start conditions, the ratio of reformer gas volume to intake gas volume is adjusted to 3:7. Under low load conditions, the ratio of reformer gas volume to intake gas volume is adjusted to 1:3. Under medium load conditions, the ratio of reformer gas volume to intake gas volume is adjusted to 1:4.

[0051] In this implementation, under cold start conditions, the low engine temperature and higher proportion of reformed gas improve ignition success rate, rapidly warm up and maintain combustion chamber temperature, prevent stalling, and reduce incomplete combustion. Under low load conditions, engine speed and throttle opening remain low, resulting in a low methanol-gas mixture concentration in the combustion chamber, making stalling more likely, and nitrogen oxides are generated in localized high-temperature zones. By adding reformed gas, the combustion speed is reduced, making combustion more stable, reducing emissions, and lowering the possibility of stalling. Under medium load conditions, engine combustion efficiency is high, but more oxygen is needed to support combustion. Therefore, compared to low load conditions, the proportion of reformed gas is reduced to support high power output and high combustion efficiency.

[0052] According to further embodiments of this disclosure, adjusting the ratio of reforming gas volume to intake gas volume to 1:3 under low load conditions further includes: when the intake air temperature is less than or equal to 0°C, adjusting the fuel injection volume during the reforming process to 1.25 times the preset fuel injection volume; when the intake air temperature is greater than 0°C and less than 30°C, adjusting the fuel injection volume during the reforming process to 1.2 times the preset fuel injection volume; and when the intake air temperature is greater than or equal to 30°C, adjusting the fuel injection volume during the reforming process to 1.1 times the preset fuel injection volume.

[0053] In this implementation, when the intake air temperature is less than or equal to 0°C, the fuel injection amount during the reforming process is 1.25 times the preset fuel injection amount, while the normal combustion process injects fuel according to the preset fuel injection amount. This allows the methanol-gas mixture to ignite rapidly and stably under the promotion of a large amount of reformed gas such as carbon monoxide, hydrogen, and formaldehyde. When the intake air temperature is greater than 0°C and less than 30°C, the fuel injection amount during the reforming process is 1.2 times the preset fuel injection amount, while the normal combustion process injects fuel according to the preset fuel injection amount. Because the intake air temperature is slightly higher, the combustion state in the combustion chamber is improved, so the fuel injection amount during the reforming process is appropriately reduced. When the intake air temperature is greater than or equal to 30°C, the fuel injection amount during the reforming process is further reduced to 1.1 times the preset fuel injection amount to avoid excessively high fuel concentration in the combustion chamber, which would lead to increased fuel consumption.

[0054] In one exemplary embodiment, under medium load conditions, adjusting the ratio of reforming gas volume to intake gas volume to 1:4 further includes: when the intake air temperature is less than or equal to 25°C, adjusting the fuel injection volume during the reforming process to 1.2 times the preset fuel injection volume; when the intake air temperature is greater than 25°C, adjusting the fuel injection volume during the reforming process to 1.1 times the preset fuel injection volume.

[0055] In this implementation, under medium load conditions, when the temperature is less than or equal to 25°C (i.e., less than or equal to ambient temperature), the lower intake air temperature reduces the conversion efficiency of the reforming reaction. Therefore, appropriately increasing the reforming fuel injection quantity promotes a more complete and thorough reforming reaction, while generating more reformed gas to participate in conventional combustion, which is beneficial for improving combustion performance. When the temperature is greater than 25°C (i.e., greater than ambient temperature), the increased intake air temperature improves the conversion efficiency of the reforming reaction, and the required methanol-gas mixture concentration is reduced. Appropriately reducing the reforming fuel injection quantity reduces fuel consumption and avoids over-reaction.

[0056] In one exemplary embodiment, under high load conditions and when the intake air temperature is less than or equal to 20°C, the ratio of the reforming gas volume to the intake air volume is adjusted to 3:13, and the fuel injection volume during the reforming process is adjusted to 1.1 times the preset fuel injection volume.

[0057] In this implementation, since the engine is under high load, both the intake air volume and the fuel injection volume are high, and the engine load is also high with strong power output. Therefore, the reforming gas volume is appropriately reduced again to avoid excessive dilution of the methanol mixture. This also reduces the incomplete combustion of hydrocarbons, carbon monoxide, etc. in the reforming gas volume, thereby reducing engine emissions.

[0058] In one exemplary embodiment, under high load conditions and when the intake air temperature is greater than 20°C, the reforming reaction is stopped and the reformed gas is no longer circulated.

[0059] In this implementation, when the engine is under high load and the intake air temperature is greater than 20°C, it no longer relies on reformed gas to assist combustion, and the engine internals are completely converted to conventional / normal combustion, i.e., four-stroke working mode.

[0060] Figure 3 This is a schematic diagram of the working principle of the methanol engine provided in this disclosure. Figure 4 This is a schematic diagram of the working principle of a methanol engine provided in another embodiment of this disclosure.

[0061] Exemplary embodiments of this disclosure also provide a methanol engine controlled using the control method of any of the above embodiments, including a cylinder block 1 and an intake section 2. The cylinder block 1 internally forms a reforming chamber 11 and a plurality of working chambers 12. The intake section 2 is configured to supply air into the reforming chamber 11 and the working chambers 12 to form a methanol mixture with methanol fuel. The reforming chamber 11 is adapted to allow the methanol mixture to undergo a reforming reaction to generate reformed gas. The intake section 2 is further configured to supply the reformed gas from the reforming chamber 11 to the working chambers 12 and is configured to adjust the supply amount in response to at least one of engine speed, throttle pedal opening, and intake air temperature.

[0062] In such an implementation, such as Figure 3 and Figure 4 The cylinder block 1 shown has at least one reforming chamber 11 and multiple working chambers 12. In the reforming chamber 11, air and methanol fuel are mixed to form a methanol-gas mixture, which is then reformed to generate reformed gas. In the working chambers 12, the methanol-gas mixture and the reformed gas from the reforming chamber 11 are mixed and combusted. The intake section 2 adjusts the amount of reformed gas incorporated into the working chambers 12 based on at least one of engine speed, throttle pedal opening, and intake air temperature to ensure stable ignition of the engine under various operating conditions and improve fuel efficiency.

[0063] In one exemplary embodiment, the air intake section 2 includes an intake pipe 21, a circulation pipe 22, and a regulating valve 23. The intake pipe 21 has a first inlet and multiple first outlets. The first inlet is in communication with the external environment, and the multiple first outlets are respectively connected to the reforming chamber 11 and the working chamber 12 to guide air in and form a methanol-gas mixture. The circulation pipe 22 has a second inlet and multiple second outlets. The second inlet is connected to the reforming chamber 11, and the second outlets are connected to the working chamber 12 to guide reformed circulating gas into the working chamber 12. The first and second outlets are connected to the working chamber 12 via the regulating valve 23, which is adapted to adjust the ratio between the methanol-gas mixture and the reformed circulating gas entering the working chamber 12.

[0064] In this embodiment, the cylinder block 1 is equipped with multiple intake and exhaust valves. Each reforming chamber 11 is equipped with at least one intake valve and at least one exhaust valve, and each working chamber 12 is equipped with at least one intake valve and at least one exhaust valve for allowing gas to enter or exit. The intake pipe 21, connected to the intake valves of the reforming chamber 11 and the working chamber 12, delivers air to them. The second inlet of the circulation pipe 22 is connected to the exhaust valve of the reforming chamber 11, and the second outlet of the circulation pipe 22 is connected to the intake valve of the working chamber 12, delivering reformed circulating gas to the working chamber 12.

[0065] Examples such as Figure 3 and Figure 4 As shown, four chambers are formed inside the cylinder block 1, one of which is a reforming chamber 11 and the other three are working chambers 12. The intake pipe 21 delivers outside air to the reforming chamber 11 and the working chambers 12. The methanol mixture in the reforming chamber 11 undergoes a reforming reaction, and the resulting reformed circulating gas is sent to the working chamber 12 by the circulation pipe 22.

[0066] According to an embodiment of the present disclosure, the intake section 2 further includes a plurality of regulating valves 23. The first outlet of the intake pipe 21 and the second outlet of the circulation pipe 22 are connected to the intake valve of the working chamber 12 through the regulating valves 23. The regulating valves 23 are configured to change the access opening of the circulation pipe 22 to regulate the delivery amount of the reforming circulation gas.

[0067] In this implementation, the intake pipe 21 and the circulation pipe 22 converge at the first regulating valve 23 and are then connected to the intake valve of the working chamber 12. For example, the regulating valve 23 is a two-inlet, one-outlet solenoid valve, with the two inlets connected to the intake pipe 21 and the circulation pipe 22 respectively, and the outlet of the solenoid valve connected to the exhaust valve of the working chamber 12. The amount of reformed circulating air delivered is adjusted by changing the valve opening.

[0068] In one exemplary embodiment, the methanol engine further includes a plurality of pistons 3, each piston 3 having a reforming chamber 11 or a working chamber 12 defined by the top of the piston 3 and the inner wall of the cylinder block 1.

[0069] In this embodiment, the piston 3 can reciprocate along the axial direction of the reforming chamber 11 or the working chamber 12 to compress and ignite the methanol mixture or the mixture of methanol and reforming recycle gas.

[0070] Furthermore, a reforming catalytic coating is formed on the surface of the piston 3 in the reforming chamber 11 to catalyze the reforming reaction of the methanol mixture.

[0071] For example, the reforming catalyst coating can use alumina or zirconium oxide as a support and copper-based catalyst (Cu / ZnO / Al2O3) as the active component.

[0072] In one exemplary embodiment, the methanol engine further includes an injector 4, which is disposed directly above the reforming chamber 11 or the working chamber 12 for injecting methanol fuel.

[0073] In one exemplary embodiment, the methanol engine further includes an exhaust section 5 configured to guide exhaust gases from the reforming chamber 11 or the working chamber 12 to the external environment.

[0074] In this embodiment, the exhaust gas in the reforming chamber 11 is generated by the combustion of methanol mixture alone after the engine stops the reforming reaction under high load conditions. The exhaust gas in the working chamber 12 is generated by the combustion of methanol mixture alone, or by the combustion of methanol mixture and reforming cycle gas, and is discharged to the external environment through the exhaust section 5.

[0075] According to an embodiment of this disclosure, the exhaust section 5 includes an exhaust pipe 51 and a valve 52. The exhaust pipe 51 is adapted to connect the exhaust valve of the working chamber 12 to the external environment to guide exhaust gas out. The valve 52 is configured to have a first state of connecting the exhaust pipe 51 and the circulation pipe 22, and a second state of disconnecting the exhaust pipe 51 and the circulation pipe 22.

[0076] In this implementation, in the first state, the exhaust pipe 51 and the circulation pipe 22 are connected. At this time, no reforming reaction occurs in the reforming chamber 11; instead, the methanol mixture is burned in the same way as in the working chamber 12. The resulting exhaust gas is discharged to the external environment through the exhaust pipe 51 and the circulation pipe 22. In the second state, the exhaust pipe 51 and the circulation pipe 22 are disconnected. A reforming reaction occurs in the reforming chamber 11, and the resulting reformed circulating gas enters the working chamber 12 under the guidance of the circulation pipe 22, instead of entering the exhaust pipe 51. The first and second mixtures are mixed and burned in the working chamber 12, and the resulting exhaust gas is discharged to the external environment under the guidance of the exhaust pipe 51.

[0077] Those skilled in the art will understand that the features described in the various embodiments of this disclosure can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in this disclosure. In particular, the features described in the various embodiments of this disclosure can be combined and / or combined in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or combinations fall within the scope of this disclosure.

[0078] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A control method for an in-cylinder reforming methanol engine, characterized in that, include: Obtain engine speed and accelerator pedal opening information to determine engine operating conditions; Adjust the mixing ratio of reformed gas volume to intake gas volume according to the operating conditions described above; The engine intake air temperature is obtained, and the fuel injection quantity during the reforming process is adjusted based on the intake air temperature.

2. The control method according to claim 1, characterized in that, When the engine speed is lower than the preset speed, it is determined to be a cold start condition; When the engine speed is greater than the preset speed and the accelerator pedal opening is less than 20%, it is determined to be a low load condition. When the engine speed is greater than the preset speed and the accelerator pedal opening is between 20% and 70%, it is judged as a medium load condition. When the engine speed is greater than the preset speed and the accelerator pedal opening is greater than 70%, it is determined to be a high load condition.

3. The control method according to claim 2, characterized in that, Under the cold start condition, the ratio of the reformed gas volume to the intake gas volume is adjusted to 3:7; Under the low-load condition, the ratio of the reforming gas volume to the intake gas volume is adjusted to 1:

3. Under the medium load condition, the ratio of the reforming gas volume to the intake gas volume is adjusted to 1:

4.

4. The control method according to claim 3, characterized in that, Under low-load conditions, adjusting the ratio of the reformed gas volume to the intake gas volume to 1:3 also includes: When the intake air temperature is less than or equal to 0℃, adjust the fuel injection quantity during the reforming process to 1.25 times the preset fuel injection quantity; When the intake air temperature is greater than 0℃ and less than 30℃, adjust the fuel injection quantity during the reforming process to 1.2 times the preset fuel injection quantity; When the intake air temperature is greater than or equal to 30°C, adjust the fuel injection quantity during the reforming process to 1.1 times the preset fuel injection quantity.

5. The control method according to claim 3, characterized in that, Under medium load conditions, adjusting the ratio of the reformed gas volume to the intake gas volume to 1:4 also includes: When the intake air temperature is less than or equal to 25°C, adjust the fuel injection quantity during the reforming process to 1.2 times the preset fuel injection quantity; When the intake air temperature is greater than 25°C, adjust the fuel injection quantity during the reforming process to 1.1 times the preset fuel injection quantity.

6. The control method according to claim 3, characterized in that, Under the high-load conditions, and when the intake air temperature is less than or equal to 20°C, the ratio of the reforming gas volume to the intake air volume is adjusted to 3:13, and the fuel injection volume during the reforming process is adjusted to 1.1 times the preset fuel injection volume.

7. The control method according to claim 3, characterized in that, Under the high-load conditions and when the intake air temperature is greater than 20°C, the reforming reaction is stopped and the reformed gas is no longer circulated.

8. A methanol engine, characterized in that, Control is performed using the control method described in any one of claims 1-7, comprising: The cylinder block has a reforming chamber and multiple working chambers inside. The air intake is configured to supply air into the reforming chamber and the working chamber to form a methanol mixture with the methanol fuel; The reforming chamber is adapted to allow a methanol-gas mixture to undergo a reforming reaction to generate reformed gas; the intake section is further configured to deliver the reformed gas from the reforming chamber to the working chamber and is configured to adjust the delivery amount in response to at least one of engine speed, throttle pedal opening and intake air temperature.

9. The methanol engine according to claim 8, characterized in that, The air intake section includes: The intake pipe has a first inlet and multiple first outlets. The first inlet is connected to the external environment, and the multiple first outlets are respectively connected to the reforming chamber and the working chamber to guide air in and form the methanol mixture. The circulation pipeline has a second inlet and multiple second outlets. The second inlet is connected to the reforming chamber, and the second outlet is connected to the working chamber to guide the reformed circulating gas into the working chamber. A regulating valve, the first outlet and the second outlet are connected to the working chamber through the regulating valve, which is suitable for adjusting the ratio between the methanol mixture and the reforming recycle gas entering the working chamber.

10. The methanol engine according to claim 8, characterized in that, It also includes a plurality of pistons, each piston top defining the reforming chamber or the working chamber with the inner wall of the cylinder body.

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