Methanol engine, vehicle and control method of methanol engine

Abstract

The present application relates to the technical field of vehicles, and particularly discloses a methanol engine, a vehicle and a control method of the methanol engine, the methanol engine comprising multiple air intake assemblies, each air intake assembly comprising an air intake passage, an air intake valve, a methanol injector and an air blowing pipeline, the air intake passage comprising a first air passage and a second air passage that are connected at an angle, the methanol injector being arranged in the first air passage, the air intake valve being used to open or close the output end of the second air passage, the second air passage comprising a first space on the side of the air intake valve facing the first air passage and a second space on the side of the air intake valve facing away from the first air passage, the air blowing pipeline being in communication with the second space and being used to blow air into the second space, and the air being capable of forming a rotational flow around the air intake valve in the second air passage, so as to promote the methanol in the second air passage to flow around the air intake valve, and then make the methanol in the first space and the second space tend to be uniformly distributed, thereby ensuring the homogenization degree of the mixed gas of the methanol and the air after entering the cylinder.

Description

Technical Field

[0001] This invention relates to the field of vehicle technology, and in particular to a methanol engine, a vehicle, and a control method for the methanol engine. Background Technology

[0002] Using methanol as fuel in internal combustion engines can improve the absorption capacity of renewable energy and is an important measure to significantly reduce engine emissions such as nitrogen oxides and particulate matter.

[0003] like Figure 1 As shown, a methanol engine typically includes a compressor, an intake manifold, an intake header, and multiple intake ports connected in sequence. The intake manifold is equipped with an intercooler and a throttle valve. The multiple intake ports correspond one-to-one with multiple cylinders, and the end of each intake port is controlled to open and close via an intake valve. The intake ports include a first intake port connected to the intake header and a second intake port for supplying fuel and air to the cylinders. A methanol injector is located in the first intake port, and the second intake port surrounds the outer periphery of the intake valve. The first and second intake ports are connected and are set at an angle. When the intake valve is open, fresh outside air is pressurized by the compressor and enters the intake manifold. It is then cooled by the intercooler and enters the intake header. It is then distributed to the first intake ports of each intake port and drives the methanol injected by the methanol injector into the second intake port, and finally into the cylinder.

[0004] However, the methanol injector imparts kinetic energy to the methanol during injection, causing the methanol entering the first air passage to migrate directionally under the influence of inertial potential energy. Additionally, the air entering the first air passage also drives the methanol's directional transport. The second air passage, separated by the intake valve, is divided into a first space facing and directly connected to the first air passage (e.g., ...). Figure 1 Part A), and the second space away from the first airway (such as... Figure 1 (Part B) After methanol enters the second air passage under its own inertial force and the drive of airflow, it will accumulate more in the second space. That is, there is relatively more methanol in the second space and relatively less methanol in the first space. This will lead to uneven distribution of methanol in the second air passage, which will affect the homogenization of the air-methanol mixture entering the cylinder. Summary of the Invention

[0005] The purpose of this invention is to provide a methanol engine, a vehicle, and a control method for the methanol engine, so as to improve the uniformity of methanol distribution in the second air passage, thereby ensuring the homogenization of the air-methanol mixture entering the cylinder.

[0006] In a first aspect, the present invention provides a methanol engine comprising a plurality of intake components, each intake component including an intake duct, an intake valve, and a methanol injector. The intake duct includes a first air passage and a second air passage connected at an angle. The methanol injector is disposed in the plurality of first air passages. The intake valve is used to open or close the output end of the second air passage. The second air passage includes a first space located on the side of the intake valve facing the first air passage, and a second space located on the side of the intake valve facing away from the first air passage. The intake component further includes an air blowing pipe communicating with the second space of the second air passage. The air blowing pipe is used to blow air into the second space, and the air can form a swirling flow around the intake valve in the second air passage.

[0007] As a preferred technical solution for a methanol engine, the blowing pipeline includes a main pipeline and multiple branch pipelines that are all connected to the main pipeline. The sidewall of the second air passage is provided with multiple nozzles, and the multiple branch pipelines are connected to the multiple nozzles one by one.

[0008] The plurality of nozzles are arranged sequentially at intervals along the axial direction of the air intake valve.

[0009] As a preferred technical solution for the methanol engine, the sum of the areas of the plurality of nozzles is S1, the area of ​​the end of the first space communicating with the first air passage is S2, and the ratio of S1 to S2 is between 0.2 and 0.7; and / or,

[0010] The ratio of the inner diameter of the second air passage to the inner diameter of the nozzle is n, where 20 ≤ n ≤ 30.

[0011] As a preferred technical solution for a methanol engine, the perpendicular line between the center of the nozzle and the centerline of the intake valve is L1, the centerline of the nozzle is L2, and the angle between L1 and L2 is α, where 30°≤α≤60°.

[0012] As a preferred technical solution for a methanol engine, the methanol engine further includes a compressor, an intake pipe, an intercooler, a throttle valve, and an intake manifold. The intake pipe is connected between the output end of the compressor and the intake manifold. The intercooler and the throttle valve are both located on the intake pipe, and the throttle valve is located between the intercooler and the intake manifold. The intake manifold is connected to the first air passage of each intake passage.

[0013] As a preferred technical solution for the methanol engine, the methanol engine further includes a bleed air pipeline connected to each of the blowing air pipelines, and a solenoid valve disposed in the bleed air pipeline, wherein the bleed air pipeline is connected to the output end of the compressor.

[0014] In a second aspect, the present invention provides a vehicle comprising a methanol engine as described in any of the above embodiments, the vehicle further comprising a gearbox, a drive shaft and a drive axle connected in sequence, the methanol engine being connected in transmission with the gearbox.

[0015] Thirdly, the present invention provides a control method for a methanol engine, executed by any of the methanol engines described in the above-mentioned schemes, the control method for the methanol engine comprising:

[0016] S100: Obtain engine speed and torque;

[0017] S110: Determine the engine's motion load based on the engine's speed and torque;

[0018] S120: Determine the target airflow rate Q1 of the intake manifold and the target airflow rate Q2 of the blowing pipe based on the motion load of the engine;

[0019] S130: The methanol injection parameters are determined based on the target airflow rate of the intake duct and the target airflow rate of the blowing pipe. The methanol injection parameters include the methanol injection quantity, the opening phase angle of the methanol injector, and the closing phase angle of the methanol injector.

[0020] S140: When the phase angle of the crankshaft is equal to the opening phase angle of the methanol injector, the methanol injector starts to inject methanol based on the methanol injection parameters, and the flow rate of the air input into the intake manifold is adjusted to Q1, and the flow rate of the air input into the blowing pipe is adjusted to Q2.

[0021] S150: When the phase angle of the crankshaft is equal to the closing phase angle of the methanol injector, the methanol injector stops injecting methanol.

[0022] As a preferred technical solution for the control method of a methanol engine, between step S140 and step S150, the following is also included:

[0023] S1410: Determine the target pressure inside the cylinder based on the motion load of the engine;

[0024] S1420: Obtain the actual pressure inside the cylinder and adjust the air flow rate of the intake manifold and the air flow rate of the blow-through manifold based on the difference between the target pressure and the actual pressure.

[0025] As a preferred technical solution for the control method of a methanol engine, between step S120 and step S130, the following is also included:

[0026] S1210: The air blowing line supplies air into the second air passage to preheat the walls of the second air passage.

[0027] As a preferred technical solution for the control method of a methanol engine, in step S120, when determining the target airflow Q1 of the intake duct based on the engine's motion load, the engine's motion load is inversely correlated with the target airflow Q1 of the intake duct.

[0028] The beneficial effects of this invention are as follows:

[0029] This invention provides a methanol engine, a vehicle, and a control method for the methanol engine. The methanol engine includes multiple intake components, each including an intake duct, an intake valve, a methanol injector, and an air blowing pipe. The intake duct includes a first air passage and a second air passage connected at an angle. The methanol injector is disposed in the first air passage. The intake valve is used to open or close the output end of the second air passage. The second air passage includes a first space located on the side of the intake valve facing the first air passage, and a second space located on the side of the intake valve facing away from the first air passage. The air blowing pipe is connected to the second space of the second air passage and is used to blow air into the second space, and the air can form a swirling flow around the intake valve in the second air passage. By generating a swirling flow in the second air passage, methanol in the second air passage can be made to flow around the intake valve, thereby making the methanol in the first space and the second space tend to be uniformly distributed, ensuring the homogeneity of the methanol-air mixture after entering the cylinder. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of a partial structure of a methanol engine in the prior art;

[0031] Figure 2 This is a schematic diagram of the methanol engine in an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of a first partial structure of the methanol engine in an embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of the second partial structure of the methanol engine in an embodiment of the present invention;

[0034] Figure 5 This is a first flowchart of the control method for a methanol engine in an embodiment of the present invention;

[0035] Figure 6 This is a second flowchart of the control method for a methanol engine in an embodiment of the present invention;

[0036] Figure 7 This is a third flowchart of the control method for a methanol engine in an embodiment of the present invention;

[0037] Figure 8 This is the fourth flowchart of the control method for a methanol engine in an embodiment of the present invention.

[0038] In the picture:

[0039] 1. Air intake; 101. First air intake; 102. Second air intake; 103. First space; 104. Second space; 105. Nozzle;

[0040] 2. Intake valve; 3. Methanol injector;

[0041] 4. Air blowing line; 41. Main line; 42. Branch line;

[0042] 5. Cylinder; 6. Compressor; 7. Intake pipe; 8. Intercooler; 9. Throttle valve; 10. Intake manifold; 11. Solenoid valve; 12. Exhaust system; 13. Exhaust pipe; 14. Turbine; 15. Bleed air line; 16. Control unit. Detailed Implementation

[0043] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions. Furthermore, "above," "on top of," and "over" the first feature in relation to the second feature includes the first feature directly above and diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "under," and "below" the first feature in relation to the second feature includes the first feature directly below and diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0045] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0046] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0047] This embodiment provides a methanol engine that can be used in vehicles or ships. This embodiment uses the application of a methanol engine in a vehicle as an example for illustration.

[0048] Please refer to Figure 2 and Figure 3 The methanol engine includes multiple intake components, including an intake manifold 1, an intake valve 2, and a methanol injector 3. The intake manifold 1 includes a first intake passage 101 and a second intake passage 102 connected at an angle. The methanol injector 3 is disposed in the first intake passage 101. The intake valve 2 is used to open or close the output end of the second intake passage 102. Specifically, when the intake valve 2 is open, the output end of the second intake passage 102 communicates with the inner cavity of the cylinder 5; when the intake valve 2 is closed, the output end of the second intake passage 102 is disconnected from the inner cavity of the cylinder 5. The second intake passage 102 includes a first space 103 located on the side of the intake valve 2 facing the first intake passage 101 (e.g., ...). Figure 3 As shown in Part A), and the second space 104 located on the side of the intake valve 2 opposite to the first air passage 101 (as ...). Figure 3 (As shown in Part B). When intake valve 2 opens, methanol injector 3 injects methanol fuel into the first intake port 101. During injection, the methanol undergoes a process of fragmentation, evaporation, and atomization. Driven by air supplied to the first intake port 101, the methanol passes through the second intake port 102 and enters the cylinder 5, awaiting subsequent combustion. Most of the methanol absorbs heat during its journey from the first intake port 101 to the cylinder 5, forming gaseous methanol that gradually mixes with air.

[0049] In this embodiment, the connection between the first airway 101 and the second airway 102 is smoothly transitioned so that air can flow smoothly between them.

[0050] In related technologies, the methanol injector imparts kinetic energy to the methanol during the injection process, causing the methanol entering the first air passage to migrate directionally under the drive of inertial force. In addition, the air entering the first air passage also drives the methanol to be transported in a direction. After entering the second air passage under the drive of its own inertial potential energy and airflow, the methanol will accumulate more in the second space. That is, there is relatively more methanol distributed in the second space and relatively less methanol distributed in the first space. This will lead to uneven distribution of methanol in the second air passage, which will affect the homogenization of the air-methanol mixture entering the cylinder.

[0051] In this embodiment, the intake assembly further includes an air blowing pipe 4, which is connected to the second space 104 of the second air passage 102. The air blowing pipe 4 is used to blow air into the second space 104, and the air can form a swirling flow around the intake valve 2 in the second air passage 102. With this configuration, by generating a swirling flow in the second air passage 102, the methanol in the second air passage 102 can be made to flow around the intake valve 2, thereby making the methanol in the first space 103 and the second space 104 more uniformly distributed, ensuring the homogenization of the methanol-air mixture after entering the cylinder 5.

[0052] In some embodiments, the methanol injector 3 is directed approximately toward the center of the connection between the first air passage 101 and the second air passage 102, so that methanol can smoothly enter the second air passage 102 under the action of its own inertial potential energy and air drive.

[0053] In some embodiments, please refer to Figure 2 The methanol engine also includes a compressor 6, an intake pipe 7, an intercooler 8, a throttle valve 9, and an intake manifold 10. The intake pipe 7 connects the output end of the compressor 6 and the intake manifold 10. The intercooler 8 and the throttle valve 9 are both located in the intake pipe 7, with the throttle valve 9 situated between the intercooler 8 and the intake manifold 10. The intake manifold 10 is connected to the first air passage 101 of each intake passage 1. With this configuration, when the throttle valve 9 is opened, fresh outside air is compressed into the intake pipe 7 by the compressor 6. After heat exchange in the intercooler 8, the air temperature decreases, and then it enters the intake manifold 10 through the throttle valve 9, and is distributed to the intake passages 1 of each intake component. Because the air is cooled by the intercooler 8, more air can enter the cylinder 5 through the intake passage 1, ensuring intake efficiency.

[0054] In some embodiments, please continue to refer to Figure 2The methanol engine also includes an exhaust system 12, an exhaust pipe 13, and a turbine 14. The exhaust system 12 includes an exhaust manifold, multiple exhaust passages, and multiple exhaust valves. Each exhaust passage corresponds to one of the multiple cylinders 5, and each exhaust valve corresponds to one of the multiple exhaust passages. The exhaust valves are used to open or close the corresponding exhaust passage. When the exhaust valve opens the corresponding exhaust passage, the exhaust passage connects to the corresponding cylinder 5. The exhaust manifold connects to each exhaust passage and is also connected to the exhaust pipe 13. The exhaust pipe 13 is connected to the turbine 14, and the turbine 14 is driven by the compressor 6. When cylinder 5 exhausts, the exhaust valve opens, and the exhaust gas produced by methanol combustion in cylinder 5 is collected in the exhaust manifold through the exhaust passages and enters the turbine 14 through the exhaust pipe 13 to drive the turbine 14 to rotate. The turbine 14 then drives the compressor 6 to work, utilizing the energy of the exhaust gas to pressurize the outside fresh air.

[0055] In some embodiments, please continue to refer to Figure 2 The methanol engine also includes a bleed air line 15 connected to each blow-through line 4, and a solenoid valve 11 disposed in the bleed air line 15. The bleed air line 15 is connected to the output end of the compressor 6. This configuration allows the compressor 6 to supply compressed air to the bleed air line 15, which is used to generate swirling flow in the second air passage 102. Furthermore, the air in the bleed air line 15, compared to the air in the intake line 7, does not require cooling by the intercooler 8, thus having a relatively higher temperature and pressure. This allows it to smoothly enter the second air passage 102 through the blow-through line 4 under the influence of pressure difference, and during methanol injection, the relatively high temperature further vaporizes any incompletely vaporized methanol in the second air passage 102. It also allows for preheating of the intake passage 1 wall at a relatively high temperature before methanol injection, increasing the wall temperature and facilitating complete vaporization of the methanol during injection. In other embodiments, a compressor for pressurizing air can be separately disposed at the inlet end of the bleed air line 15 as needed.

[0056] In some embodiments, an electric heating wire is provided in the air intake pipe 15 to raise the temperature of the passing air, so that the air entering the second air passage 102 through the air blowing pipe 4 has a higher temperature, thereby enhancing the vaporization effect of methanol in the second air passage 102 and the preheating effect on the wall of the second air passage 102.

[0057] In some embodiments, the air blowing pipeline 4 includes a main pipeline 41 and a plurality of branch pipelines 42 all connected to the main pipeline 41. The sidewall of the second air passage 102 is provided with a plurality of nozzles 105, and the plurality of branch pipelines 42 are connected to the plurality of nozzles 105 in a one-to-one correspondence. The plurality of nozzles 105 are arranged sequentially at intervals along the axial direction of the intake valve 2. With this arrangement, air is injected into the second space 104 through the plurality of nozzles 105, forming multiple swirling flows along the axial direction of the intake valve 2. This more effectively drives the air-methanol mixture in the entire second air passage 102 to move circumferentially around the intake valve 2, thereby further improving the uniformity of methanol distribution in the second air passage 102.

[0058] In some embodiments, the number of branch pipes 42 and nozzles 105 is between three and six. For example, the number of branch pipes 42 and nozzles 105 is three, four, five, or six. Of course, in other embodiments, the number of branch pipes 42 and nozzles 105 can be set to one, two, or more than six, depending on actual needs.

[0059] In some embodiments, the main pipe 41 and the branch pipe 42 of the air blowing pipe 4 have circular cross-sections and smooth inner walls to facilitate the smooth passage of air through the air blowing pipe 4.

[0060] In some embodiments, the ratio between the inner diameter of the main pipe 41 and the inner diameter of the nozzle 105 is between 5 and 8. Specifically, the ratio between the inner diameter of the main pipe 41 and the inner diameter of the nozzle 105 can be 5, 5.5, 6, 6.5, 7, 7.5, or 8, etc.

[0061] In some embodiments, the sum of the areas of the plurality of nozzles 105 is S1, and the area of ​​the end of the first space 103 communicating with the first air passage 101 is S2. The ratio of S1 to S2 is between 0.2 and 0.7. This configuration ensures that the air entering the second air passage 102 through the plurality of nozzles 105 can effectively drive the methanol-air mixture in the second air passage 102 to generate a swirling flow. Specifically, the ratio of S1 to S2 can be 0.2, 0.3, 0.4, 0.5, 0.6, or 0.7, etc.

[0062] In some embodiments, the ratio of the inner diameter of the second air passage 102 to the inner diameter of the nozzle 105 is n, where 20 ≤ n ≤ 30. This configuration effectively ensures that the inner diameter of the second air passage 102 matches the orifice diameter of the nozzle 105, thereby ensuring that the air ejected from the nozzle 105 generates a more stable swirling flow in the second air passage 102. Specifically, the value of n can be 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30.

[0063] In this embodiment, the cross-section of the second air passage 102 is approximately circular, and the inner diameter of the second air passage 102 is specifically the average inner diameter of the portion of the second air passage 102 located between the plurality of nozzles 105.

[0064] In some embodiments, please refer to Figure 4 The perpendicular line between the center of the nozzle 105 and the centerline of the intake valve 2 is L1, the centerline of the nozzle 105 is L2, and the angle between L1 and L2 is α, where 30°≤α≤60°. This arrangement allows the air entering the second air passage 102 through the nozzle 105 to generate a swirling flow around the intake valve 2. Furthermore, it allows the air entering the second air passage 102 to gradually move away from its wall, facilitating direct and sufficient contact with the methanol in the second space 104. This allows the partially vaporized methanol to better absorb heat and undergo secondary vaporization. The value of α can be 30°, 35°, 40°, 45°, 50°, 55°, or 60°, etc.

[0065] In other embodiments, the center of the nozzle 105 can also be perpendicular to the center line of the intake valve 2. In this case, the air entering the second air passage 102 will move along the outer periphery of the second air passage 102, which can also generate swirling flow in the second air passage 102.

[0066] In some embodiments, the methanol engine further includes a control unit 16, which is electrically connected to the solenoid valve 11 and the throttle valve 9, respectively. The control unit 16 is used to control the opening degree of the solenoid valve 11 and the opening degree of the throttle valve 9.

[0067] This embodiment also provides a vehicle including the aforementioned methanol engine. The vehicle further includes a gearbox, a drive shaft, and a drive axle connected in sequence. The methanol engine is connected to the gearbox, and the drive axle is connected to the wheel ends. This vehicle can ensure that methanol is evenly distributed in the intake manifold 1 before entering the cylinder 5, thereby ensuring the homogeneity of the methanol-air mixture after entering the cylinder 5.

[0068] This embodiment also provides a control method for a methanol engine, which is executed by the methanol engine described above.

[0069] Specifically, please refer to Figure 5 The control method for this methanol engine includes the following steps.

[0070] S100: Obtain engine speed and torque.

[0071] The engine speed can be detected by a speed sensor, and the engine torque can be detected by a torque sensor.

[0072] S110: Determine the engine's motion load based on the engine's speed and torque.

[0073] Specifically, the memory pre-stores a first correspondence between engine speed, torque, and engine load. The engine load is determined based on the acquired engine speed and torque, as well as the first correspondence. This first correspondence can be determined based on extensive prior experiments.

[0074] S120: Determine the target airflow rate Q1 of intake duct 1 and the target airflow rate Q2 of blowing line 4 based on the engine's motion load.

[0075] The airflow rate of intake manifold 1 is the flow rate of air delivered to intake manifold 10, and the airflow rate of blow-through pipe 4 is the flow rate of air delivered to blow-through pipe 4 via bleed pipe 15, which is also the flow rate of air delivered to second air passage 102 via blow-through pipe 4. The airflow rates of intake manifold 1 and blow-through pipe 4 together determine the total airflow rate supplied to cylinder 5 by intake manifold 1. Specifically, when the airflow rate of intake manifold 1 equals the target airflow rate Q1, and the airflow rate of blow-through pipe 4 equals the target airflow rate Q2, the airflow rate supplied to cylinder 5 by intake manifold 1 can meet the airflow requirements of the engine's operating load.

[0076] Specifically, the memory pre-stores a second correspondence between the engine's operating load and the target airflow of the intake duct 1 and the target airflow of the blowing pipe 4. Based on the engine's operating load and the second correspondence, the target airflow of the intake duct 1 and the target airflow of the blowing pipe 4 can be determined. The second correspondence can be determined through extensive prior experiments.

[0077] In some embodiments, in step S120, when determining the target airflow Q1 of the intake manifold 1 based on the engine's operating load, the engine's operating load is inversely correlated with the target airflow Q1 of the intake manifold 1. This setting can prevent excessive high-temperature gas in the cylinder 5 from causing accelerated combustion and knocking when the engine's operating load is too high.

[0078] Specifically, when the engine's operating load does not exceed 40% of the engine's maximum operating load, the opening degree of solenoid valve 11 is controlled at more than 60% of the maximum opening degree of solenoid valve 11; when the engine's operating load exceeds 40% of the engine's maximum operating load, the opening degree of solenoid valve 11 is controlled between 20% and 60% of the maximum opening degree of solenoid valve 11. This allows the methanol-air mixture in the second intake port 102 to effectively swirl while avoiding in-cylinder knocking, promoting a uniform distribution of methanol in the second intake port 102.

[0079] S130: Determine the methanol injection parameters based on the target airflow rate of intake duct 1 and the target airflow rate of blowing line 4.

[0080] The methanol injection parameters include the methanol injection quantity, the opening phase angle of methanol injector 3, and the closing phase angle of methanol injector 3. It can be understood that both the opening and closing phase angles of methanol injector 3 correspond to the crankshaft phase angle. As the engine crankshaft rotates, its phase angle continuously changes. When the crankshaft phase angle equals the opening phase angle of methanol injector 3, methanol injector 3 begins to inject methanol. When the crankshaft's limiting angle equals the closing phase angle of methanol injector 3, methanol injector 3 closes. Therefore, the opening and closing phase angles of methanol injector 3 determine the methanol injection duration. Based on the methanol injection quantity and the methanol injection duration, the injection quantity within a given time period can be determined.

[0081] Specifically, the memory pre-stores a third correspondence between the target airflow of intake duct 1, the target airflow of blowing pipe 4, and the methanol injection parameters. The methanol injection parameters can be determined based on the target airflow of intake duct 1, the target airflow of blowing pipe 4, and the third correspondence. The third correspondence can be obtained through extensive prior experiments.

[0082] Step S130 ensures that the methanol injection parameters are matched with the target airflow rates of the intake manifold 1 and the blow-through pipe 4, thereby guaranteeing complete vaporization and combustion of methanol within the cylinder 5. Furthermore, the engine's operating load is primarily determined by the amount of air and methanol entering the cylinder 5. Step S130 also establishes a correlation between the methanol injection parameters, the target airflow rates of the intake manifold 1 and the blow-through pipe 4, and the engine's operating load, thereby satisfying the engine's operating load requirements.

[0083] S140: When the phase angle of the crankshaft is equal to the opening phase angle of the methanol injector 3, the methanol injector 3 starts to inject methanol based on the methanol injection parameters, and the air flow rate input to the intake duct 1 is adjusted to Q1, and the air flow rate input to the blowing pipe 4 is adjusted to Q2.

[0084] Through step S140, in the initial stage of methanol injection by methanol injector 3, the air flow rate input into intake duct 1 is maintained at Q1, and the air flow rate input into blowing pipe 4 is maintained at Q2. This can theoretically meet the current engine load requirements, while also ensuring the formation of a stable vortex in the second air passage 102, so that the methanol-air mixture is evenly distributed in the second air passage 102. In addition, the air input into the second air passage 102 through blowing pipe 4 can also fully re-vaporize the methanol.

[0085] When methanol injector 3 injects methanol based on the methanol injection parameters, the injection duration of methanol injector 3 is equal to the time difference between the opening phase angle and the closing phase angle of methanol injector 3, the amount of methanol injected by methanol injector 3 is equal to the methanol injection quantity, and the pressure of methanol injected by methanol injector 3 remains stable.

[0086] Please refer to Figure 6 In step S140, adjusting the airflow rate of the air entering through the intake duct 1 to Q1 and the airflow rate of the air entering through the blowing pipe 4 to Q2 includes the following steps:

[0087] S1401: Determine the first initial opening of the throttle valve 9 based on the target airflow of the intake duct 1.

[0088] With the compressor 6 rotating at a constant speed, the opening of the throttle valve 9 directly determines the flow rate of air delivered from the compressor 6 to the intake manifold 10, and thus determines the flow rate of cold air delivered from the intake manifold 10 to each intake duct 1.

[0089] Specifically, the memory pre-stores a fourth correspondence between the target airflow of the intake duct 1 and the first initial opening of the throttle valve 9. The first initial opening of the throttle valve 9 can be determined based on the target airflow of the intake duct 1 and the fourth correspondence. The fourth correspondence can be determined through extensive prior experiments.

[0090] S1402: Determine the second initial opening degree of solenoid valve 11 based on the target air flow rate of air blowing line 4.

[0091] With the compressor 6 rotating at a constant speed, the opening of the solenoid valve 11 directly determines the flow rate of air delivered to the intake pipe 15 through the compressor 6, and thus determines the flow rate of air delivered to each intake pipe 1 through the blowing pipe 4.

[0092] Specifically, the memory pre-stores a fifth correspondence between the target airflow of the air blowing pipe 4 and the second initial opening degree of the solenoid valve 11. The second initial opening degree of the solenoid valve 11 can be determined based on the target airflow of the air blowing pipe 4 and the fifth correspondence. The fifth correspondence can be determined through extensive prior experiments.

[0093] S1403: Adjust the throttle valve 9 to the first initial opening and the solenoid valve 11 to the second initial opening.

[0094] S150: When the phase angle of the crankshaft is equal to the closing phase angle of the methanol injector 3, the methanol injector 3 stops injecting methanol.

[0095] The methanol engine control method provided in this embodiment, through the above steps S100 to S150, can ensure that the mixture of methanol and air is evenly distributed in the second air passage 102 during the methanol injection process, and can also ensure that the methanol is fully vaporized twice, thereby ensuring the stability of the combustion reaction in the cylinder 5.

[0096] In some embodiments, step S150 further includes: keeping the throttle valve 9 and solenoid valve 11 open until the intake valve 2 closes. This allows the methanol in the intake manifold 1 to be fully vaporized. The closing time of the throttle valve 9 and solenoid valve 11 is delayed by 10°-20°CA relative to the closing time of the methanol injector 3.

[0097] Please continue to refer to Figure 5 In some embodiments, the control method for the methanol engine further includes steps S1410 and S1420 located between steps S140 and S150.

[0098] S1410: Determine the target pressure within cylinder 5 based on the engine's motion load.

[0099] The memory pre-stores a sixth correspondence between the engine's operating load and the target pressure inside cylinder 5. Based on the engine's operating load and the sixth correspondence, the target pressure inside cylinder 5 can be determined. The sixth correspondence can be determined through extensive prior experiments.

[0100] S1420: Obtain the actual pressure inside cylinder 5, and adjust the air flow rate of intake duct 1 and air flow rate of blowing pipe 4 based on the difference between target pressure and actual pressure.

[0101] The actual pressure inside cylinder 5 can be obtained through a pressure sensor. During the actual operation of a methanol engine, it may be affected by external environmental factors such as temperature and altitude, as well as by its own internal factors such as performance degradation due to prolonged use. This can easily lead to a situation where the engine's operating load cannot meet expectations when the throttle valve 9 maintains its first initial opening and the solenoid valve 11 maintains its second initial opening. The above steps can effectively prevent this from happening.

[0102] Specifically, when the actual pressure inside cylinder 5 is equal to the target pressure, or the difference between the two pressures is within a set range, it can reliably ensure that the combustion work done in the cylinder meets the current engine load.

[0103] Specifically, please refer to Figure 7 Step S1420 includes the following steps S1421-S1426.

[0104] S1421: Obtain the actual pressure inside cylinder 5 and calculate the difference between the actual pressure and the target pressure.

[0105] S1422: Determine whether the difference exceeds the upper limit of the set range.

[0106] If yes, then execute S1423; otherwise, execute S1424.

[0107] S1423: Increase the opening of the throttle valve 9 by the first set value, decrease the opening of the solenoid valve 11 by the second set value, and return to step S1421.

[0108] S1424: Determine whether the difference exceeds the lower limit of the set range.

[0109] If yes, then execute S1425; otherwise, execute S1426.

[0110] S1425: Decrease the opening of throttle valve 9 by the third setting value, and increase the opening of solenoid valve 11 by the fourth setting value.

[0111] S1426: Determine that the difference between the target pressure and the actual pressure is within the set range.

[0112] Through the above steps S1421 to S1426, the opening degree of the solenoid valve 11 and the opening degree of the throttle valve 9 can be synchronously controlled, thereby effectively regulating the flow rate of air input from the intake manifold 10 to the intake passage 1 and the flow rate of air input from the blow pipe 4 to the second air passage 102, so as to adjust the actual pressure in the cylinder 5 to the target pressure, thereby meeting the engine's operating load.

[0113] The methanol engine control method provided in this embodiment, through the above steps S1410 to S1420, enables the actual pressure inside the cylinder to match the target pressure; in addition, it can couple the swirling flow in the second air passage 102 with the methanol injection process, and use the swirling flow to achieve secondary atomization of methanol droplets in the second air passage 102, thereby improving the uneven distribution of the mixed gas in the second air passage 102.

[0114] In some embodiments, between steps S120 and S130, the methanol engine control method further includes step S1210.

[0115] S1210: Air is supplied from the air blowing line 4 to the second air passage 102 to preheat the wall of the second air passage 102.

[0116] With this configuration, before methanol injection, air is introduced into the second air passage 102 through the air blowing pipe 4. Since the air temperature is relatively high, it can effectively preheat the wall of the second air passage 102. At the same time, since the second air passage 102 is connected to the first air passage 101, it can also preheat the wall of the first air passage 101. When methanol is injected, since the wall temperature of the intake passage 1 is relatively high, when the injected methanol adheres to the inner wall of the intake passage 1, it can absorb the heat of the wall of the intake passage 1 and then vaporize, ensuring the vaporization effect of methanol.

[0117] Specifically, please refer to Figure 8 Step S1210 includes the following steps.

[0118] S1211: Determine the opening phase angle, closing phase angle, and third initial opening degree of solenoid valve 11 based on the methanol injection quantity.

[0119] In this embodiment, the closing phase angle of the solenoid valve 11 is advanced compared to the opening phase angle of the methanol injector 3. This embodiment exemplifies a scheme where the closing phase angle of the solenoid valve 11 is advanced by 30°CA relative to the opening phase angle of the methanol injector 3.

[0120] Specifically, the memory pre-sets a seventh correspondence between the methanol injection rate and the opening and closing phase angles of the solenoid valve 11. Based on the methanol injection rate and the seventh correspondence, the opening phase angle, closing phase angle, and third initial opening degree of the solenoid valve 11 are determined. The seventh correspondence can be obtained through extensive prior experiments.

[0121] In this embodiment, the opening phase angle and the closing phase angle of the solenoid valve 11 both correspond to the phase angle of the crankshaft. As the crankshaft rotates, the phase angle of the crankshaft changes continuously. When the phase angle of the crankshaft is equal to the opening phase angle of the solenoid valve 11, the solenoid valve 11 opens to the third initial opening degree. When the limiting angle of the crankshaft is equal to the closing phase angle of the solenoid valve 11, the solenoid valve 11 closes.

[0122] S1212: When the phase angle of the crankshaft is equal to the opening phase angle of the solenoid valve 11, adjust the solenoid valve 11 to the third initial opening degree.

[0123] Since the closing phase angle of the solenoid valve 11 is earlier than the opening phase angle of the methanol injector 3, that is, the solenoid valve 11 opens before the methanol injector 3 injects, allowing the hot air in the blowing pipe 4 to enter the second air passage 102 and partially flow into the first air passage 101. This can preheat the inner wall of the air intake passage 1, so that when the methanol injector 3 is opened later, the air intake passage 1 has a higher temperature, so that the methanol adhering to the inner wall of the air intake passage 1 can absorb heat and vaporize, ensuring the vaporization effect of methanol.

[0124] S1213: When the phase angle of the crankshaft is equal to the closing phase angle of solenoid valve 11, solenoid valve 11 is closed.

[0125] The above description is merely a preferred embodiment of the present invention and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of disclosure in this invention is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-disclosed concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this invention.

[0126] Furthermore, while several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of the invention. Certain features described in the context of individual embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0127] Although the subject matter has been described using language specific to structural features and / or methodological logic, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely illustrative examples of implementing the claims.

Claims

1. A methanol engine comprising a plurality of intake components, the intake components including an intake duct (1), an intake valve (2), and a methanol injector (3), the intake duct (1) including a first air passage (101) and a second air passage (102) connected at an angle, the methanol injector (3) being disposed in the first air passage (101), the intake valve (2) being used to open or close the output end of the second air passage (102), the second air passage (102) including a first space (103) located on the side of the intake valve (2) facing the first air passage (101), and a second space (104) located on the side of the intake valve (2) away from the first air passage (101); characterized in that, The air intake assembly also includes an air blowing pipe (4), which is connected to the second space (104) of the second air passage (102). The air blowing pipe (4) is used to blow air into the second space (104) and the air can form a swirling flow around the air intake door (2) in the second air passage (102). The air blowing pipeline (4) includes a main pipeline (41) and multiple branch pipelines (42) that are all connected to the main pipeline (41). The side wall of the second air passage (102) is provided with multiple nozzles (105), and the multiple branch pipelines (42) are connected to the multiple nozzles (105) one by one. The plurality of nozzles (105) are arranged sequentially at intervals along the axial direction of the air intake valve (2); The perpendicular line between the center of the nozzle (105) and the center line of the intake valve (2) is L1, the center line of the nozzle (105) is L2, and the included angle between L1 and L2 is α, 30°≤α≤60°.

2. The methanol engine according to claim 1, characterized in that, The sum of the areas of the plurality of nozzles (105) is S1, the area of ​​the end of the first space (103) communicating with the first air passage (101) is S2, and the ratio of S1 to S2 is between 0.2 and 0.7; and / or, The ratio of the inner diameter of the second air passage (102) to the inner diameter of the nozzle (105) is n, where 20 ≤ n ≤ 30.

3. The methanol engine according to any one of claims 1-2, characterized in that, The methanol engine also includes a compressor (6), an intake pipe (7), an intercooler (8), a throttle valve (9), and an intake manifold (10). The intake pipe (7) is connected between the output end of the compressor (6) and the intake manifold (10). The intercooler (8) and the throttle valve (9) are both located on the intake pipe (7), and the throttle valve (9) is located between the intercooler (8) and the intake manifold (10). The intake manifold (10) is connected to the first air passage (101) of each intake passage (1).

4. The methanol engine according to claim 3, characterized in that, The methanol engine also includes an air intake pipe (15) connected to each of the air blowing pipes (4), and a solenoid valve (11) disposed in the air intake pipe (15), the air intake pipe (15) being connected to the output end of the compressor (6).

5. A vehicle, characterized in that, The vehicle includes the methanol engine according to any one of claims 1-4, and further includes a gearbox, a drive shaft and a drive axle connected in sequence, wherein the methanol engine is connected in transmission to the gearbox.

6. A control method for a methanol engine, characterized in that, The methanol engine is operated by any one of claims 1-5, and the control method of the methanol engine includes: S100: Obtain engine speed and torque; S110: Determine the engine's motion load based on the engine's speed and torque; S120: Determine the target airflow rate Q1 of the intake duct (1) and the target airflow rate Q2 of the blowing pipe (4) based on the motion load of the engine; S130: The methanol injection parameters are determined based on the target airflow of the intake duct (1) and the target airflow of the blowing pipe (4). The methanol injection parameters include the methanol injection quantity, the opening phase angle of the methanol injector (3), and the closing phase angle of the methanol injector (3). S140: When the phase angle of the crankshaft is equal to the opening phase angle of the methanol injector (3), the methanol injector (3) starts to inject methanol based on the methanol injection parameters, and the air flow rate input to the intake duct (1) is adjusted to Q1, and the air flow rate input to the blowing pipe (4) is adjusted to Q2. S150: When the phase angle of the crankshaft is equal to the closing phase angle of the methanol injector (3), the methanol injector (3) stops injecting methanol.

7. The control method for a methanol engine according to claim 6, characterized in that, Between step S140 and step S150, the following is also included: S1410: Determine the target pressure inside cylinder (5) based on the motion load of the engine; S1420: Obtain the actual pressure inside the cylinder (5) and adjust the air flow rate of the intake manifold (1) and the air flow rate of the blowing pipe (4) based on the difference between the target pressure and the actual pressure.

8. The control method for a methanol engine according to claim 6, characterized in that, Between step S120 and step S130, the following is also included: S1210: The air blowing pipe (4) supplies air into the second air passage (102) to preheat the wall of the second air passage (102).

9. The control method for a methanol engine according to claim 6, characterized in that, In step S120, the target airflow Q1 of the intake duct (1) is determined based on the motion load of the engine. At that time, the motion load of the engine is inversely related to the target airflow Q1 of the intake duct (1).

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