Engine combustion system based on methanol fuel

Abstract

The invention discloses an engine combustion system based on methanol fuel, and belongs to the technical field of engines, and the system is characterized in that a first outlet of a methanol storage tank is communicated to a gas inlet channel methanol nozzle of a main combustion chamber; a second outlet of the methanol storage tank is communicated to a first inlet of the waste gas heat exchanger, and is communicated to a first inlet of the methanol reformer through a first outlet of the waste gas heat exchanger; a first outlet of the methanol reformer is communicated to a gas inlet channel reformed gas nozzle of the main combustion chamber and a pre-combustion chamber reformed gas nozzle; an exhaust pipe outlet of the main combustion chamber communicates with a second inlet of the waste gas heat exchanger so as to communicate with a second inlet of the methanol reformer through a second outlet of the waste gas heat exchanger. Waste gas waste heat is used for methanol vaporization and reforming reaction, hydrogen-rich reformed gas is generated, the waste gas waste heat is efficiently utilized, the energy utilization rate is increased, the reformed gas is introduced into the pre-combustion chamber and the main combustion chamber, jet flow ignition energy is enhanced, in-cylinder combustion is accelerated, and the combustion efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of engine technology, and more particularly to an engine combustion system based on methanol fuel. Background Technology

[0002] Currently, methanol, as a low-carbon oxygenated fuel, has advantages such as wide availability and clean combustion, and its use in marine engines is becoming increasingly widespread.

[0003] In related technologies, methanol engines typically incorporate a main combustion chamber and a pre-combustion chamber to further accelerate combustion and improve the engine's heat release rate. However, in practical applications, traditional methanol engines have been found to suffer from low energy utilization and insufficient combustion efficiency.

[0004] In summary, the technical problems existing in the relevant technologies need to be improved. Summary of the Invention

[0005] This application provides an engine combustion system based on methanol fuel, which can efficiently utilize waste heat, improve energy utilization, enhance jet ignition energy and accelerate in-cylinder combustion, thereby improving combustion efficiency.

[0006] On one hand, embodiments of this application provide an engine combustion system based on methanol fuel, the system comprising: a main combustion chamber, a pre-combustion chamber, a methanol storage tank, an exhaust gas heat exchanger, and a methanol reformer;

[0007] The first outlet of the methanol storage tank is connected to the methanol nozzle in the intake duct of the main combustion chamber.

[0008] The second outlet of the methanol storage tank is connected to the first inlet of the waste gas heat exchanger, and then connected to the first inlet of the methanol reformer via the first outlet of the waste gas heat exchanger.

[0009] The first outlet of the methanol reformer is connected to the reforming gas nozzle in the intake duct of the main combustion chamber and the reforming gas nozzle in the pre-combustion chamber.

[0010] The exhaust pipe outlet of the main combustion chamber is connected to the second inlet of the exhaust gas heat exchanger, and then connected to the second inlet of the methanol reformer via the second outlet of the exhaust gas heat exchanger.

[0011] The second outlet of the methanol reformer is connected to the waste gas treatment device.

[0012] Optionally, the system further includes: an electronic control unit;

[0013] The electronic control unit is electrically connected to the intake manifold reforming nozzle and the pre-combustion chamber reforming nozzle.

[0014] The electronic control unit is used to adjust the injection pulse width of the intake reforming nozzle and the pre-combustion chamber reforming nozzle.

[0015] Optionally, a hydrogen concentration sensor is provided at the first outlet of the methanol reformer;

[0016] The hydrogen concentration sensor is electrically connected to the electronic control unit;

[0017] The electronic control unit is also used to adjust the injection pulse width of the reforming gas nozzle in the pre-combustion chamber based on the hydrogen concentration data collected by the hydrogen concentration sensor.

[0018] Optionally, an exhaust temperature sensor is provided at the exhaust pipe outlet of the main combustion chamber;

[0019] The exhaust temperature sensor is electrically connected to the electronic control unit.

[0020] Optionally, the exhaust gas heat exchanger is equipped with a first electric heating module;

[0021] The first electric heating module is electrically connected to the electronic control unit.

[0022] Optionally, the methanol reformer is equipped with a second electric heating module;

[0023] The second electric heating module is electrically connected to the electronic control unit.

[0024] Optionally, a cylinder pressure sensor is provided in the main combustion chamber;

[0025] The cylinder pressure sensor is electrically connected to the electronic control unit;

[0026] The electronic control unit is also used to calculate the combustion center of gravity based on the cylinder pressure data collected by the cylinder pressure sensor.

[0027] Optionally, after calculating the combustion center of gravity based on the cylinder pressure data collected by the cylinder pressure sensor, the method further includes:

[0028] The electronic control unit is also used to adjust the ignition advance angle of the spark plug in the pre-combustion chamber based on the calculation result of the combustion center of gravity.

[0029] Optionally, a methanol throttling valve is also provided between the second outlet of the methanol storage tank and the first inlet of the waste gas heat exchanger;

[0030] The methanol throttle valve is electrically connected to the electronic control unit.

[0031] Optionally, the nozzle between the pre-combustion chamber and the main combustion chamber adopts a multi-hole microchannel design.

[0032] This application embodiment utilizes the waste heat of exhaust gas for methanol vaporization and reforming reaction to generate hydrogen-rich reformed gas, which makes efficient use of waste heat and improves energy utilization. Furthermore, by introducing the reformed gas into the pre-combustion chamber and the main combustion chamber, the jet ignition energy is enhanced and the in-cylinder combustion is accelerated, thereby improving combustion efficiency. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of an engine combustion system based on methanol fuel provided in an embodiment of this application;

[0034] Figure 2 This is a schematic flowchart of an electronic control unit control process provided in an embodiment of this application;

[0035] The attached figures are labeled as follows:

[0036] 1: Main combustion chamber; 2: Pre-combustion chamber; 3: Methanol storage tank; 4: Exhaust gas heat exchanger; 5: Methanol reformer; 6: Intake duct methanol nozzle; 7: Intake duct reformer nozzle; 8: Pre-combustion chamber reformer nozzle; 9: Electronic control unit; 10: Hydrogen concentration sensor; 11: Exhaust temperature sensor; 12: First electric heating module; 13: Second electric heating module; 14: Cylinder pressure sensor; 15: Methanol throttle valve. Detailed Implementation

[0037] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the embodiments of the present application. They are merely examples of devices and methods consistent with some aspects of the embodiments of the present application as detailed in the appended claims.

[0038] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various concepts, but unless otherwise stated, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the words “if,” “when,” or “in response to a determination” as used herein may be interpreted as “when…” or “when…” or “in response to a determination.”

[0039] As used in this application, the terms "at least one", "multiple", "each", "any", etc., "at least one" includes one, two or more, "multiple" includes two or more, "each" refers to each of the corresponding multiples, and "any" refers to any one of the multiples.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0041] Currently, methanol, as a low-carbon oxygenated fuel, has advantages such as wide availability and clean combustion, and its use in marine engines is becoming increasingly widespread.

[0042] In related technologies, methanol engines typically incorporate a main combustion chamber and a pre-combustion chamber to further accelerate combustion and improve the engine's heat release rate. However, in practical applications, traditional methanol engines have been found to suffer from low energy utilization and insufficient combustion efficiency.

[0043] In view of this, this application provides an engine combustion system based on methanol fuel, which utilizes waste heat from exhaust gas for methanol vaporization and reforming reaction to generate hydrogen-rich reformed gas, making efficient use of waste heat and improving energy utilization. Furthermore, by introducing the reformed gas into the pre-combustion chamber and the main combustion chamber, the jet ignition energy is enhanced and in-cylinder combustion is accelerated, thereby improving combustion efficiency.

[0044] The specific implementation methods of the embodiments of this application will be described in detail below with reference to the accompanying drawings. First, an engine combustion system based on methanol fuel provided in an embodiment of this application will be described with reference to the accompanying drawings.

[0045] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of an engine combustion system based on methanol fuel provided in an embodiment of this application. The engine combustion system based on methanol fuel includes: a main combustion chamber 1, a pre-combustion chamber 2, a methanol storage tank 3, an exhaust gas heat exchanger 4, and a methanol reformer 5.

[0046] The first outlet of the methanol storage tank 3 is connected to the methanol nozzle 6 in the intake duct of the main combustion chamber 1.

[0047] The second outlet of the methanol storage tank 3 is connected to the first inlet of the waste gas heat exchanger 4, and then connected to the first inlet of the methanol reformer 5 via the first outlet of the waste gas heat exchanger 4.

[0048] The first outlet of the methanol reformer 5 is connected to the reforming gas nozzle 7 of the intake duct of the main combustion chamber 1 and the reforming gas nozzle 8 of the pre-combustion chamber 2.

[0049] The exhaust pipe outlet of the main combustion chamber 1 is connected to the second inlet of the exhaust gas heat exchanger 4, and then connected to the second inlet of the methanol reformer 5 via the second outlet of the exhaust gas heat exchanger 4.

[0050] The second outlet of the methanol reformer 5 is connected to the waste gas treatment device.

[0051] In the embodiments of this application, such as Figure 1 As shown, the combustion system of the methanol-fueled engine mainly consists of a main combustion chamber 1 and a pre-combustion chamber 2. The first outlet of the methanol storage tank 3 is connected to the methanol nozzle 6 in the intake duct of the main combustion chamber 1. Liquid methanol is mixed with air and sent into the main combustion chamber 1 through the methanol nozzle 6 in the intake duct of the main combustion chamber. It can improve the engine's thermal efficiency and output power by utilizing ultra-lean combustion technology. It has significant advantages such as reducing heat transfer loss, improving the working fluid adiabatic index, suppressing knock tendency, and significantly reducing NOx generation.

[0052] Furthermore, the second outlet of the methanol storage tank 3 is connected to the first inlet of the exhaust gas heat exchanger 4, and then to the first inlet of the methanol reformer 5 via the first outlet of the exhaust gas heat exchanger 4. At the same time, the exhaust pipe outlet of the main combustion chamber 1 is connected to the second inlet of the exhaust gas heat exchanger 4, and then to the second inlet of the methanol reformer 5 via the second outlet of the exhaust gas heat exchanger 4. This allows liquid methanol to be transported to the exhaust gas heat exchanger 4, where it is heated and vaporized by heat exchange with the high-temperature exhaust gas before being further transported to the methanol reformer 5. The methanol undergoes a catalytic cracking reaction at the methanol reformer 5, producing hydrogen-rich reformed gas. The heat-exchanged exhaust gas enters the methanol reformer 5, providing heat for the catalytic reforming of methanol, and is then discharged from the second outlet of the methanol reformer 5 to the atmosphere or an exhaust gas treatment device for further treatment.

[0053] Finally, the reformed gas generated by catalytic reforming is transmitted through the first outlet to the intake reformed gas nozzle 7 of the main combustion chamber 1 and the pre-combustion chamber reformed gas nozzle 8 of the pre-combustion chamber 2. The reformed gas is mixed with methanol / air in the main combustion path through the intake reformed gas nozzle 7 of the main combustion chamber 1 to form a more easily ignitable mixture. The mixture is then delivered to the pre-combustion chamber 2 through the pre-combustion chamber reformed gas nozzle 8 as a highly active medium for jet ignition.

[0054] Therefore, the methanol-fuel-based engine combustion system provided in this application utilizes the waste heat from the exhaust gas discharged from the main combustion chamber 1 through the exhaust gas heat exchanger 4 to use the exhaust gas waste heat for methanol vaporization and reforming reaction, generating hydrogen-rich reformed gas, thereby improving energy utilization. The reformed gas is simultaneously introduced into the pre-combustion chamber 2 and the main combustion chamber 1, combined with ultra-lean combustion technology and active pre-combustion chamber jet ignition, utilizing the high activity of hydrogen-rich fuel to enhance jet ignition energy and accelerate in-cylinder combustion, further accelerating the combustion speed and improving the engine combustion heat release rate.

[0055] Specifically, as an optional embodiment, the system further includes: an electronic control unit 9;

[0056] The electronic control unit 9 is electrically connected to the intake manifold reforming nozzle 7 and the pre-combustion chamber reforming nozzle 8.

[0057] The electronic control unit 9 is used to adjust the injection pulse width of the intake reforming nozzle 7 and the pre-combustion chamber reforming nozzle 8.

[0058] In the embodiments of this application, such as Figure 1 As shown, the methanol-fueled engine combustion system also includes an Electronic Control Unit (ECU), which is electrically connected to the intake manifold reforming nozzle 7 and the pre-combustion chamber reforming nozzle 8. Figure 1 (Electrical connections are indicated by dashed lines in the diagram). Each nozzle is connected to the electronic control unit 9 via an electrical wiring harness, enabling the electronic control unit 9 to receive electrical signals from each nozzle and also output drive commands (such as ignition triggering, adjusting injection pulse width, etc.).

[0059] In practical applications, such as Figure 1 As shown, the methanol nozzle 6 in the intake manifold can also be electrically connected to the electronic control unit 9, so that the electronic control unit 9 can control the injection pulse width of the methanol nozzle 6 in the intake manifold according to a preset control strategy.

[0060] Specifically, as an optional embodiment, a hydrogen concentration sensor 10 is provided at the first outlet of the methanol reformer 5;

[0061] The hydrogen concentration sensor 10 is electrically connected to the electronic control unit 9;

[0062] The electronic control unit 9 is also used to adjust the injection pulse width of the reforming gas nozzle 8 in the pre-combustion chamber based on the hydrogen concentration data collected by the hydrogen concentration sensor 10.

[0063] In the embodiments of this application, such as Figure 1 As shown, by installing a hydrogen concentration sensor 10 at the first outlet of the methanol reformer 5, the hydrogen concentration in the reformed gas is detected in real time. When the fluctuation of the hydrogen concentration exceeds the preset value (such as ±5%), the electronic control unit 9, which is electrically connected to the hydrogen concentration sensor 10, can dynamically adjust the injection pulse width of the reformed gas nozzle 8 in the pre-combustion chamber to maintain the stability of the jet flame and ignition energy.

[0064] In practical applications, the total fuel energy in the pre-combustion chamber must remain stable. When the methanol reformer 5 is working stably, the hydrogen concentration in the reformed gas output should also remain stable. If the engine load or exhaust temperature changes, the hydrogen concentration in the reformed gas may fluctuate and deviate from the stable value under the design conditions. In this case, it is necessary to adjust the injection pulse width of the reformed gas nozzle 8 in the pre-combustion chamber. When the hydrogen concentration decreases, the pulse width is increased to compensate for the ignition energy; when the hydrogen concentration increases, the pulse width is decreased to avoid overburning in the pre-combustion chamber, ensure the stability of the jet flame in the pre-combustion chamber, and maintain stable ignition energy.

[0065] Specifically, as an optional embodiment, an exhaust temperature sensor 11 is provided at the exhaust pipe outlet of the main combustion chamber 1;

[0066] The exhaust temperature sensor 11 is electrically connected to the electronic control unit 9.

[0067] In the embodiments of this application, such as Figure 1 As shown, by installing an exhaust temperature sensor 11 at the exhaust pipe outlet of the main combustion chamber 1 and then electrically connecting the exhaust temperature sensor 11 to the electronic control unit 9, the electronic control unit 9 can determine the exhaust gas temperature to be delivered to the exhaust gas heat exchanger by acquiring the exhaust gas temperature data in the exhaust duct of the main combustion chamber collected by the exhaust temperature sensor 11.

[0068] In practical applications, such as Figure 1 As shown, a first electric heating module 12 can also be provided in the exhaust gas heat exchanger 4, and a second electric heating module 13 can be provided in the methanol reformer 5. The first electric heating module 12 and the second electric heating module 13 are electrically connected to the electronic control unit 9.

[0069] Therefore, when the electronic control unit 9 obtains the exhaust gas temperature data in the exhaust duct of the main combustion chamber collected by the exhaust temperature sensor 11 and finds that the exhaust gas temperature has not reached the temperature threshold required for methanol catalytic reforming (e.g., engine cold start), it can first activate the two electric heating modules to provide heat to ensure that methanol can be efficiently catalytically cracked. When the exhaust gas temperature reaches the standard, the electric heating modules are turned off and the exhaust gas heat exchanger 4 is switched to provide independent heating to maximize the utilization rate of exhaust gas waste heat.

[0070] Specifically, as an optional embodiment, a cylinder pressure sensor 14 is provided in the main combustion chamber 1;

[0071] The cylinder pressure sensor 14 is electrically connected to the electronic control unit 9;

[0072] The electronic control unit 9 is also used to calculate the combustion center of gravity based on the cylinder pressure data collected by the cylinder pressure sensor 14.

[0073] In the embodiments of this application, such as Figure 1As shown, a cylinder pressure sensor 14 can be installed in the main combustion chamber 1 and electrically connected to the electronic control unit 9, so that the electronic control unit 9 can obtain the combustion pressure curve and calculate the combustion center of gravity CA50 based on the cylinder pressure data collected by the cylinder pressure sensor 14.

[0074] Furthermore, a methanol throttling valve 15 is also installed between the second outlet of the methanol storage tank 3 and the first inlet of the waste gas heat exchanger 4.

[0075] The methanol throttle valve 15 is electrically connected to the electronic control unit 9.

[0076] When the electronic control unit 9 determines that the peak cylinder pressure in the main combustion chamber 1 exceeds the preset threshold, it can adjust the methanol flow rate in the reforming gas path through the methanol throttle valve 15. By reducing the reforming methanol flow rate, the intake manifold reforming gas injection volume is reduced, the in-cylinder fuel activity is reduced, the cylinder pressure is stabilized, and the methanol reforming rate and engine load demand are matched in real time to ensure the supply and demand balance of reforming gas.

[0077] In practical applications, after calculating the combustion center of gravity CA50, the ignition advance angle of the spark plug in the pre-combustion chamber 2 can be dynamically adjusted by judging whether the combustion center of gravity CA50 deviates from the preset range (0-10° crankshaft angle). The jet flame injection time is synchronized with the top dead center of the cylinder compression, ensuring that the combustion center of gravity CA50 is stable within the 0-10° crankshaft angle range, thereby achieving the matching of the combustion heat release peak with the piston stroke and improving thermal efficiency.

[0078] As an optional implementation, the nozzle between the pre-combustion chamber 2 and the main combustion chamber 1 adopts a multi-hole microchannel design.

[0079] In this embodiment, the nozzle of the pre-combustion chamber 2 can be designed with a porous microchannel, which can utilize the high diffusivity of hydrogen-rich reformed gas to form a high-intensity turbulent jet, thereby shortening the flame propagation time in the cylinder.

[0080] The following section provides a detailed introduction and explanation of the methanol-fuel-based engine combustion system provided in this application, in conjunction with a specific application implementation process:

[0081] In this embodiment of the application, a methanol-fuel-based engine combustion system is provided. This device can be applied to engine scenarios. By using the waste heat of exhaust gas for methanol vaporization and reforming reaction, hydrogen-rich reformed gas is generated, which makes efficient use of waste heat and improves energy utilization. Furthermore, by introducing the reformed gas into the pre-combustion chamber and the main combustion chamber, the jet ignition energy is enhanced and the in-cylinder combustion is accelerated, thereby improving combustion efficiency.

[0082] Specifically, such as Figure 1As shown, the combustion system of the methanol-fueled engine mainly consists of a main combustion chamber 1 and a pre-combustion chamber 2. The first outlet of the methanol storage tank 3 is connected to the methanol nozzle 6 in the intake duct of the main combustion chamber 1. Liquid methanol is mixed with air and sent into the main combustion chamber 1 through the methanol nozzle 6 in the intake duct of the main combustion chamber. It can improve the engine's thermal efficiency and output power by utilizing ultra-lean combustion technology. It has significant advantages such as reducing heat transfer loss, improving the working fluid adiabatic index, suppressing knock tendency, and significantly reducing NOx generation.

[0083] Furthermore, the second outlet of the methanol storage tank 3 is connected to the first inlet of the exhaust gas heat exchanger 4, and then to the first inlet of the methanol reformer 5 via the first outlet of the exhaust gas heat exchanger 4. At the same time, the exhaust pipe outlet of the main combustion chamber 1 is connected to the second inlet of the exhaust gas heat exchanger 4, and then to the second inlet of the methanol reformer 5 via the second outlet of the exhaust gas heat exchanger 4. This allows liquid methanol to be transported to the exhaust gas heat exchanger 4, where it is heated and vaporized by heat exchange with the high-temperature exhaust gas before being further transported to the methanol reformer 5. The methanol undergoes a catalytic cracking reaction at the methanol reformer 5, producing hydrogen-rich reformed gas. The heat-exchanged exhaust gas enters the methanol reformer 5, providing heat for the catalytic reforming of methanol, and is then discharged from the second outlet of the methanol reformer 5 to the atmosphere or an exhaust gas treatment device for further treatment.

[0084] Finally, the reformed gas generated by catalytic reforming is transmitted through the first outlet to the intake reformed gas nozzle 7 of the main combustion chamber 1 and the pre-combustion chamber reformed gas nozzle 8 of the pre-combustion chamber 2. The reformed gas is mixed with methanol / air in the main combustion path through the intake reformed gas nozzle 7 of the main combustion chamber 1 to form a more easily ignitable mixture. The mixture is then delivered to the pre-combustion chamber 2 through the pre-combustion chamber reformed gas nozzle 8 as a highly active medium for jet ignition.

[0085] Furthermore, the methanol-fueled engine combustion system is also equipped with an electronic control unit 9, please refer to... Figure 2 , Figure 2 This is a schematic diagram of the control process of an electronic control unit provided in an embodiment of this application. Taking engine start-up as an example, by setting an exhaust temperature sensor 11 at the exhaust pipe outlet of the main combustion chamber 1 and then electrically connecting the exhaust temperature sensor 11 to the electronic control unit 9, the electronic control unit 9 can determine the exhaust gas temperature to be delivered to the exhaust gas heat exchanger by acquiring the exhaust gas temperature data in the exhaust passage of the main combustion chamber collected by the exhaust temperature sensor 11.

[0086] In practical applications, such as Figure 1 As shown, a first electric heating module 12 can also be provided in the exhaust gas heat exchanger 4, and a second electric heating module 13 can be provided in the methanol reformer 5. The first electric heating module 12 and the second electric heating module 13 are electrically connected to the electronic control unit 9.

[0087] Therefore, when the electronic control unit 9 obtains the exhaust gas temperature data in the exhaust duct of the main combustion chamber collected by the exhaust temperature sensor 11 and finds that the exhaust gas temperature has not reached the temperature threshold required for methanol catalytic reforming (e.g., engine cold start), it can first activate the two electric heating modules to provide heat to ensure that methanol can be efficiently catalytically cracked. When the exhaust gas temperature reaches the standard, the electric heating modules are turned off and the exhaust gas heat exchanger 4 is switched to provide independent heating to maximize the utilization rate of exhaust gas waste heat.

[0088] Furthermore, by installing a hydrogen concentration sensor 10 at the first outlet of the methanol reformer 5, the hydrogen concentration in the reformed gas is detected in real time. When the fluctuation of the hydrogen concentration exceeds a preset value (such as ±5%), the electronic control unit 9, which is electrically connected to the hydrogen concentration sensor 10, can dynamically adjust the injection pulse width of the reformed gas nozzle 8 in the pre-combustion chamber to maintain the stability of the jet flame and ignition energy.

[0089] In addition, a cylinder pressure sensor 14 can be installed in the main combustion chamber 1 and electrically connected to the electronic control unit 9, so that the electronic control unit 9 can obtain the combustion pressure curve and calculate the combustion center of gravity CA50 based on the cylinder pressure data collected by the cylinder pressure sensor 14.

[0090] When the electronic control unit 9 determines that the peak cylinder pressure in the main combustion chamber 1 exceeds the preset threshold, it can adjust the methanol flow rate in the reforming gas path through the methanol throttle valve 15. By reducing the reforming methanol flow rate, the intake manifold reforming gas injection volume is reduced, the in-cylinder fuel activity is reduced, the cylinder pressure is stabilized, and the methanol reforming rate and engine load demand are matched in real time to ensure the supply and demand balance of reforming gas.

[0091] In practical applications, after calculating the combustion center of gravity CA50, the ignition advance angle of the spark plug in the pre-combustion chamber 2 can be dynamically adjusted by judging whether the combustion center of gravity CA50 deviates from the preset range (0-10° crankshaft angle). The jet flame injection time is synchronized with the top dead center of the cylinder compression, ensuring that the combustion center of gravity CA50 is stable within the 0-10° crankshaft angle range, thereby achieving the matching of the combustion heat release peak with the piston stroke and improving thermal efficiency.

[0092] After completing the above control process, the current control process of the electronic control unit 9 ends, and it waits for the arrival of the next control process node.

[0093] This application provides an engine combustion system based on methanol fuel, which utilizes waste heat from exhaust gas for methanol vaporization and reforming to generate hydrogen-rich reformed gas, thereby efficiently utilizing waste heat from exhaust gas and improving energy efficiency. Furthermore, by introducing the reformed gas into the pre-combustion chamber and the main combustion chamber, it enhances jet ignition energy and accelerates in-cylinder combustion, thereby improving combustion efficiency.

[0094] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0095] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0096] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0097] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0098] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0099] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0100] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0101] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0102] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0103] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes multiple instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing programs, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0104] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A methanol-fuel-based engine combustion system, characterized in that, The system includes: a main combustion chamber, a pre-combustion chamber, a methanol storage tank, an exhaust gas heat exchanger, and a methanol reformer; The first outlet of the methanol storage tank is connected to the methanol nozzle in the intake duct of the main combustion chamber. The second outlet of the methanol storage tank is connected to the first inlet of the waste gas heat exchanger, and then connected to the first inlet of the methanol reformer via the first outlet of the waste gas heat exchanger. The first outlet of the methanol reformer is connected to the reforming gas nozzle in the intake duct of the main combustion chamber and the reforming gas nozzle in the pre-combustion chamber. The exhaust pipe outlet of the main combustion chamber is connected to the second inlet of the exhaust gas heat exchanger, and then connected to the second inlet of the methanol reformer via the second outlet of the exhaust gas heat exchanger. The second outlet of the methanol reformer is connected to the waste gas treatment device.

2. The methanol-fuel-based engine combustion system according to claim 1, characterized in that, The system also includes: an electronic control unit; The electronic control unit is electrically connected to the intake manifold reforming nozzle and the pre-combustion chamber reforming nozzle. The electronic control unit is used to adjust the injection pulse width of the intake reforming nozzle and the pre-combustion chamber reforming nozzle.

3. The methanol-fuel-based engine combustion system according to claim 2, characterized in that, A hydrogen concentration sensor is installed at the first outlet of the methanol reformer. The hydrogen concentration sensor is electrically connected to the electronic control unit; The electronic control unit is also used to adjust the injection pulse width of the reforming gas nozzle in the pre-combustion chamber based on the hydrogen concentration data collected by the hydrogen concentration sensor.

4. The methanol-fuel-based engine combustion system according to claim 2, characterized in that, An exhaust temperature sensor is installed at the exhaust pipe outlet of the main combustion chamber; The exhaust temperature sensor is electrically connected to the electronic control unit.

5. The methanol-fuel-based engine combustion system according to claim 4, characterized in that, The exhaust gas heat exchanger is equipped with a first electric heating module; The first electric heating module is electrically connected to the electronic control unit.

6. The methanol-fuel-based engine combustion system according to claim 4, characterized in that, The methanol reformer is equipped with a second electric heating module; The second electric heating module is electrically connected to the electronic control unit.

7. The methanol-fuel-based engine combustion system according to claim 2, characterized in that, A cylinder pressure sensor is installed in the main combustion chamber; The cylinder pressure sensor is electrically connected to the electronic control unit; The electronic control unit is also used to calculate the combustion center of gravity based on the cylinder pressure data collected by the cylinder pressure sensor.

8. The methanol-fuel-based engine combustion system according to claim 7, characterized in that, After calculating the combustion center of gravity based on the cylinder pressure data collected by the cylinder pressure sensor, the method further includes: The electronic control unit is also used to adjust the ignition advance angle of the spark plug in the pre-combustion chamber based on the calculation result of the combustion center of gravity.

9. The methanol-fuel-based engine combustion system according to claim 2, characterized in that, A methanol throttling valve is also provided between the second outlet of the methanol storage tank and the first inlet of the waste gas heat exchanger. The methanol throttle valve is electrically connected to the electronic control unit.

10. The methanol-fuel-based engine combustion system according to any one of claims 1 to 9, characterized in that, The nozzle between the pre-combustion chamber and the main combustion chamber adopts a multi-hole microchannel design.

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