Methanol engine, vehicle and control method of methanol engine

Abstract

The invention 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 comprises a gas compressor, a gas inlet pipe, an intercooler, a throttle valve, a gas inlet header pipe, a gas blowing pipeline, a heating piece, a control valve and a plurality of gas inlet assemblies; the intercooler and the throttle valve are both arranged on the air inlet pipe, and the throttle valve is located between the intercooler and the air inlet header pipe. The air inlet assembly comprises air inlet channels, methanol ejectors arranged in the air inlet channels and hot air inlets communicating with the air inlet channels, the air inlet header pipe is connected with the air inlet channels, the air blowing pipeline is used for introducing fresh air and communicates with the hot air inlets, and the heating piece and the control valve are arranged in the air blowing pipeline. The heating piece is used for heating fresh air flowing through the air blowing pipeline, the opening degree of the control valve is adjustable, the control valve is used for adjusting the circulation amount of the air blowing pipeline, normal operation of the engine can be guaranteed, and the energy utilization rate is increased.

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 of renewable energy and is an important measure to significantly reduce engine emissions such as nitrogen oxides and particulate matter. However, due to its high latent heat of vaporization and the need for a large injection volume, methanol absorbs a large amount of heat during evaporation. This leads to a significant decrease in the temperature of the working fluid and walls inside the intake manifold, resulting in two adverse effects: First, the increased temperature gradient on the intake manifold walls causes some methanol fuel to form a liquid film on the intake manifold walls, resulting in instability in the amount of circulating gaseous methanol actually participating in the combustion reaction; second, the change in the thermodynamic state of the working fluid causes changes in the in-cylinder temperature field, affecting the stability of in-cylinder combustion.

[0003] To address the aforementioned issues, related technologies employ methods such as increasing the temperature of the air entering the intake manifold and distributing the air to each intake duct through the intake manifold. This allows for a more uniform mixing of methanol and the higher-temperature air within the intake ducts and prevents methanol from adhering to the walls of the intake ducts. Among the methods used to increase the temperature of the air entering the intake manifold, the following approaches are commonly employed: For example, a methanol fuel engine intake manifold system disclosed in the prior patent CN200710023316.2 directly heats the fresh air passing through the compressor electrically, and then delivers the heated air to the intake manifold; or, a methanol engine intake preheating system disclosed in the prior patent CN202421424370.3 recycles and reuses a portion of the exhaust gas, mixing it with fresh air before delivering it to the intake manifold; or, a methanol engine intake control system disclosed in the prior patent application CN202010305734.6 divides the fresh air after passing through the compressor into two parts: one part passes through an intercooler, and the other part does not, then the two parts are mixed and delivered to the intake manifold.

[0004] However, the above solution results in higher air temperature entering the intake manifold, which affects the amount of air entering the intake manifold per unit time and affects the normal operation of the engine. In addition, the heat of the air is distributed throughout the entire intake manifold and cannot be concentrated on the intake manifold wall where methanol adheres, which leads to energy waste. 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, which reduces energy waste and ensures normal engine operation while improving the problem of methanol adhering to the intake manifold wall.

[0006] In a first aspect, the present invention provides a methanol engine, which includes a compressor, an intake pipe, an intercooler, a throttle valve, an intake manifold, and multiple intake components. The compressor, the intake pipe, and the intake manifold are connected in sequence. The intercooler and the throttle valve are both disposed on the intake pipe, and the throttle valve is located between the intercooler and the intake manifold. Each intake component includes an intake duct and a methanol injector disposed in the intake duct. The intake manifold is connected to each intake duct. The methanol engine also includes a blow-through pipe, and a heating element and a control valve disposed in the blow-through pipe. The intake component also includes a hot air inlet communicating with the intake duct. A first end of the blow-through pipe is connected to each hot air inlet, and a second end of the blow-through pipe is used to introduce fresh air. The opening degree of the control valve is adjustable, and the control valve is used to adjust the flow rate of the blow-through pipe.

[0007] As a preferred technical solution for a methanol engine, the hot air inlet is located downstream of the methanol injector along the flow direction of the airflow within the intake duct.

[0008] As a preferred technical solution for a methanol engine, the hot air inlet is opened at an upward angle, and the airflow injected through the hot air inlet can provide an upward force to the methanol injected by the methanol injector.

[0009] As a preferred technical solution for a methanol engine, the centerline of the air intake, the centerline of the methanol injector, and the centerline of the hot air inlet intersect at a single point.

[0010] As a preferred technical solution for a methanol engine, the intake duct includes a first intake duct, a first arc-shaped intake duct, a second intake duct, a second arc-shaped intake duct, and a third intake duct that are connected in sequence at an angle. The first intake duct is connected to the intake manifold, and the intake valve passes through the third intake duct, and the intake valve is used to open or close the third intake duct.

[0011] Both the methanol injector and the hot air inlet are located in the first arc-shaped air passage, and the center line of the methanol injector is directed toward the center of the end of the first arc-shaped air passage that connects with the second air passage.

[0012] As a preferred technical solution for a methanol engine, the angle between the centerline of the air intake and the centerline of the methanol injector is an acute angle, and the angle between the centerline of the hot air inlet and the centerline of the methanol injector is an acute angle.

[0013] As a preferred technical solution for methanol engines, the blowing pipe 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] Obtain the engine speed and torque;

[0017] The engine's motion load is determined based on the engine's speed and torque;

[0018] The intake airflow, hot air inlet airflow, and target pressure in the cylinder are determined based on the engine's motion load.

[0019] The initial throttle opening is determined based on the airflow in the intake manifold;

[0020] The second initial opening degree of the control valve is determined based on the airflow rate at the hot air inlet;

[0021] The methanol injection parameters are determined based on the airflow rate of the intake duct and the airflow rate of the hot air inlet. 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.

[0022] The first target temperature of the heating element is determined based on the methanol injection parameters.

[0023] When the crankshaft phase angle is equal to the methanol injector opening phase angle, the methanol injector starts to inject methanol, and adjusts the throttle to the first initial opening, adjusts the control valve to the second initial opening, and adjusts the temperature of the heating element to the first target temperature.

[0024] The actual pressure inside the cylinder is obtained, and the opening of the throttle valve and the opening of the control valve are adjusted based on the difference between the target pressure and the actual pressure until the difference between the target pressure and the actual pressure is within the set range.

[0025] When the crankshaft phase angle is equal to the methanol injector's shut-off phase angle, the methanol injector stops injecting methanol.

[0026] A preferred technical solution for the control method of a methanol engine further includes a method between determining the methanol injection parameters based on the airflow rate of the intake manifold and the airflow rate of the hot air inlet, and determining the first target temperature of the heating element based on the methanol injection quantity:

[0027] The second target temperature of the heating element, the opening phase angle of the control valve, the closing phase angle of the control valve, and the third initial opening degree of the control valve are determined based on the methanol injection quantity, wherein the closing phase angle of the control valve is earlier than the opening phase angle of the methanol injector.

[0028] When the phase angle of the crankshaft is equal to the opening phase angle of the control valve, the control valve is adjusted to the third initial opening, the heating element is turned on, and the temperature of the heating element is adjusted to the third initial temperature.

[0029] When the crankshaft phase angle is equal to the control valve's closing phase angle, the control valve and heating element are closed.

[0030] The beneficial effects of this invention are as follows:

[0031] This invention provides a methanol engine, a vehicle, and a control method for the methanol engine. The methanol engine includes a compressor, an intake pipe, an intercooler, a throttle valve, an intake manifold, a blow-through pipe, a heater, a control valve, and multiple intake components. The compressor, intake pipe, and intake manifold are connected sequentially. The intercooler and throttle valve are both located in the intake pipe, with the throttle valve positioned between the intercooler and the intake manifold. The intake components include an intake duct, a methanol injector located in the intake duct, and a hot air inlet connected to the intake duct. The intake manifold is connected to each intake duct. The first end of the blow-through pipe is connected to each hot air inlet, and the second end of the blow-through pipe is used to introduce fresh air. The heater and control valve are both located in the blow-through pipe. The heater is used to heat the fresh air flowing through the blow-through pipe, and the opening of the control valve is adjustable. The control valve is used to adjust the flow rate of the blow-through pipe. Under the action of the compressor, fresh outside air is compressed and delivered to the intake manifold. Then, it undergoes heat exchange in the intercooler, lowering its temperature to become cryogenic air. When the throttle is opened, this cryogenic air enters the intake manifold and is distributed to the various intake manifolds. Because cryogenic air has a relatively high density, it ensures a sufficient intake volume per unit time, thereby ensuring a more thorough and uniform mixing of air and methanol, guaranteeing efficient air supply to the cylinders, and enabling the engine to operate more stably. Additionally, fresh outside air can also be... The air blowing pipes are introduced into each intake manifold, and as the fresh air passes through the heating element in the air blowing pipes, the heating element heats the fresh air to form hot air. The hot air has a higher pressure than the cold air, so it can be directly input into the intake manifold under the action of pressure difference. It can directly provide heat to the methanol in the intake manifold, prevent methanol from adhering to the walls, ensure the stability of combustion in the cylinder, and compared with the existing technology, the hot air is directly delivered into the intake manifold, and the temperature difference between the hot air and methanol is greater, so the methanol absorbs heat better, which can improve the energy utilization rate and reduce energy waste. Attached Figure Description

[0032] Figure 1This is a schematic diagram of the methanol engine in an embodiment of the present invention;

[0033] Figure 2 This is a partial structural diagram of the methanol engine in an embodiment of the present invention;

[0034] Figure 3 This is a first flowchart of the control method for a methanol engine in an embodiment of the present invention;

[0035] Figure 4 This is a second flowchart of the control method for a methanol engine in an embodiment of the present invention;

[0036] Figure 5 This is the third flowchart of the control method for a methanol engine in an embodiment of the present invention.

[0037] In the picture:

[0038] 1. Compressor; 2. Intake pipe; 3. Intercooler; 4. Throttle valve; 5. Intake manifold; 6. Air blowing pipe; 7. Heating element; 8. Control valve; 9. Intake passage; 91. First air passage; 92. First arc-shaped air passage; 93. Second air passage; 94. Second arc-shaped air passage; 95. Third air passage; 10. Methanol injector; 11. Hot air inlet; 12. Exhaust passage; 13. Exhaust manifold; 14. Exhaust pipe; 15. Cylinder; 16. Turbine; 17. Second temperature sensor. Detailed Implementation

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] For methanol engines, methanol absorbs a large amount of heat during evaporation due to its high latent heat of vaporization and large injection volume. This leads to a significant decrease in the temperature of the working fluid and walls inside the intake manifold. This results in an increase in the temperature gradient of the intake manifold walls, causing some methanol fuel to form a liquid film on the intake manifold walls. This makes the amount of circulating gaseous methanol that actually participates in the combustion reaction unstable. It also causes changes in the thermodynamic state of the working fluid, resulting in changes in the in-cylinder temperature field and affecting the stability of in-cylinder combustion.

[0044] In response, related technologies address this by increasing the temperature of the air entering the intake manifold and distributing it to various intake ducts through the intake manifold. This ensures a more uniform mixing of methanol and the higher-temperature air within the intake ducts and prevents methanol from adhering to the duct walls. Specifically, the fresh air passing through the compressor can be directly heated within the intake manifold (which transports compressed fresh air from the compressor to the intake manifold, distributes it to multiple intake ducts, and then delivers it to the combustion chamber of the corresponding cylinder). This heated air is then delivered to the intake manifold, increasing the temperature of the air entering the intake manifold. Alternatively, a portion of the exhaust gas can be recycled and mixed with fresh air before being delivered to the intake manifold, further increasing the temperature of the air entering the intake manifold. Another approach is to divide the fresh air after the compressor into two parts: one part passes through an intercooler, and the other does not. These two parts are then mixed before being delivered to the intake manifold, further increasing the temperature of the air entering the intake manifold. However, these solutions all result in higher air temperatures entering the intake manifold and relatively lower air density, affecting the amount of air entering the intake manifold per unit time, which in turn affects the amount of air entering the combustion chamber of the cylinder, thus affecting the normal operation of the engine. In addition, the heat of the air is distributed throughout the entire intake manifold and cannot be concentrated on the intake manifold walls where methanol adheres, leading to energy waste.

[0045] In addition, related technologies propose installing electric heating devices at locations on the intake manifold wall where a liquid film of methanol fuel can easily form. These devices provide heat to promote methanol vaporization, thereby enhancing methanol atomization and improving in-cylinder combustion stability. The electric heating devices can be installed outside the intake manifold, but this results in significant heat exchange losses; alternatively, they can be installed inside the intake manifold, but this occupies internal space and affects intake stability.

[0046] To address this issue, this embodiment provides a methanol engine. This methanol engine can be used in vehicles, ships, and the like.

[0047] Please refer to Figure 1 and Figure 2The methanol engine includes a compressor 1, an intake pipe 2, an intercooler 3, a throttle valve 4, an intake manifold 5, an air blowing pipe 6, a heater 7, a control valve 8, and multiple intake components. The compressor 1 has an input end for introducing fresh air, an intake pipe 2 connected between the output end of the compressor 1 and the intake manifold 5, an intercooler 3 and a throttle valve 4 both located in the intake pipe 2, and the throttle valve 4 located between the intercooler 3 and the intake manifold 5. The intake assembly includes an intake duct 9, a methanol injector 10 located in the intake duct 9, and a hot air inlet 11 connected to the intake duct 9. The intake manifold 5 is connected to each intake duct 9. The first end of the blowing pipe 6 is connected to each hot air inlet 11, and the second end of the blowing pipe 6 is used to introduce fresh air. A heating element 7 and a control valve 8 are both located in the blowing pipe 6. The heating element 7 is used to heat the fresh air flowing through the blowing pipe 6, and the opening of the control valve 8 is adjustable. The control valve 8 is used to adjust the flow rate of the blowing pipe 6.

[0048] Understandably, multiple intake assemblies are used to supply a mixture of air and methanol vapor to the combustion chambers of multiple cylinders 15 one by one.

[0049] The methanol engine provided in this embodiment, under the action of compressor 1, compresses and delivers fresh outside air into intake manifold 2. Then, it undergoes heat exchange in intercooler 3, lowering the air temperature to become low-temperature air. When throttle 4 opens, the low-temperature air enters intake manifold 5 and is distributed to each intake manifold 9. Because the density of low-temperature air is relatively high, the intake volume per unit time in intake manifold 9 is ensured, thereby ensuring a more uniform mixing of air and methanol. Simultaneously, it ensures efficient air supply to cylinder 15, enabling the engine to operate more stably. Furthermore, fresh outside air... Fresh air can also be introduced into each intake duct 9 through the air blowing pipe 6. When passing through the heating element 7 in the air blowing pipe 6, the fresh air is heated by the heating element 7 to form hot air. The hot air has a higher pressure than the cold air, so it can be directly input into the intake duct 9 under the action of pressure difference. It can directly provide heat to the methanol in the intake duct 9, avoid methanol adhering to the wall, ensure the stability of combustion in the cylinder, and compared with the existing technology, the hot air is directly delivered into the intake duct 9. The temperature difference between the hot air and methanol is larger, which makes the methanol absorb heat better, improves the energy utilization rate, and reduces energy waste.

[0050] In this embodiment, the control valve 8 is preferably a solenoid valve, and the heating element 7 is preferably an electric heating wire. In other embodiments, the control valve 8 may also be a hydraulically controlled valve, and the heating element 7 may also be a heat exchanger.

[0051] In some embodiments, the methanol engine further includes a first temperature sensor for detecting the temperature of the gas in the blow-through line 6. Preferably, the first temperature sensor is located downstream of the heating element 7.

[0052] In some embodiments, please refer to Figure 2 Along the airflow direction within the intake duct 9, the hot air inlet 11 is located downstream of the methanol injector 10. Because the methanol mist ejected by the methanol injector 10 moves downstream under the influence of the cold air entering the intake duct 9, it adheres to the wall of the intake duct 9 downstream of the methanol injector 10 under gravity. This methanol-attached wall forms a methanol-falling area. In this embodiment, placing the hot air inlet 11 downstream of the methanol injector 10 allows the hot air delivered from the hot air inlet 11 to the intake duct 9 to be closer to or directly act on the methanol mist in the methanol-falling area, thus fully utilizing the energy of the hot air and preventing methanol from adhering to the wall. Preferably, the hot air inlet 11 is located in the methanol-falling area so that the energy of the hot air can be directly absorbed by the methanol in the methanol-falling area.

[0053] In some embodiments, please refer to Figure 2 The hot air inlet 11 is angled upwards, and the airflow injected through the hot air inlet 11 provides an upward force to the methanol ejected by the methanol injector 10. By angled upwards, the hot air inlet 11 provides upward momentum to the methanol aerosol, allowing it to remain in the air for a longer period. When the methanol aerosol is in the air, the heat exchange area with the hot air is significantly larger than when it adheres to the wall of the air inlet 9. This allows the methanol aerosol to absorb more heat from the hot air injected through the hot air inlet 11, thus promoting complete vaporization of the methanol and preventing it from adhering to the wall.

[0054] In some embodiments, please refer to Figure 2 The centerline of the intake duct 9, the centerline of the methanol injector 10, and the centerline of the hot air inlet 11 intersect at a single point. This arrangement allows the cold air entering the intake duct 9 from the intake manifold 5 to converge with the hot air entering the intake duct 9 from the hot air inlet 11, acting on the center of the methanol spray. This results in more complete atomization of the methanol spray under the impact of the two airflows, which is more conducive to the complete vaporization of methanol. At the same time, the convergence of the center of the hot air and the center of the methanol spray also allows the methanol to absorb heat from the hot air more efficiently.

[0055] In some embodiments, when the cold air entering the intake duct 9, the methanol mist injected by the methanol injector 10, and the hot air entering the intake duct 9 through the hot air inlet 11 converge, the cold air entering the intake duct 9 through the intake pipe 2 flows in a downward direction, the hot air entering the intake duct 9 through the hot air inlet 11 flows in an upward direction, and the centerline of the methanol mist injected by the methanol injector 10 is horizontal or inclined upward, so that the mist injected by the methanol injector 10 can have a relatively long dwell time, thereby further improving the vaporization effect of methanol. In this embodiment, an example is provided where the centerline of the methanol mist injected by the methanol injector 10 is horizontal.

[0056] In some embodiments, please refer to Figure 2 The intake duct 9 includes a first air duct 91, a first arc-shaped air duct 92, a second air duct 93, a second arc-shaped air duct 94, and a third air duct 95 connected at an angle in sequence. The first air duct 91 is connected to the intake manifold 5, and the intake valve passes through the third air duct 95, which is used to open or close the third air duct 95. The methanol injector 10 and the hot air inlet 11 are both located in the first arc-shaped air duct 92, and the center line of the methanol injector 10 is directed towards the center of the end where the first arc-shaped air duct 92 connects to the second air duct 93. With this configuration, a portion of the cold air passes through the first air duct 91 and the first arc-shaped air duct 92 before contacting the methanol spray. By passing through the first arc-shaped air duct 92, the airflow direction of the cold air changes from a straight line to a swirling flow. Therefore, when the cold air acts on the methanol spray, it will not blow the methanol mist directly onto the wall of the first arc-shaped air duct 92 or the second air duct 93, but will instead blow the methanol mist into the second air duct 93, further preventing methanol from adhering to the wall. Preferably, the extension direction of the second air passage 93 is approximately parallel to the centerline direction of the methanol injector 10.

[0057] In other embodiments, the centerline of the methanol injector 10 can also be higher than the center of the end where the first arc-shaped air passage 92 and the second air passage 93 are connected, so as to increase the height of the relative methanol drop area, thereby increasing the dwell time of the methanol mist and further improving the methanol vaporization effect.

[0058] In some embodiments, please refer to Figure 2The angle between the centerline of the intake duct 9 and the centerline of the methanol injector 10 is acute, as is the angle between the centerline of the hot air inlet 11 and the centerline of the methanol injector 10. Specifically, the centerline of the first arc-shaped air passage 92 intersects the centerline of the methanol injector 10 at an acute angle. When cold air comes into contact with methanol mist, it exerts a force on the methanol mist to flow into the second air passage 93. When hot air comes into contact with methanol mist, it also exerts a force on the methanol mist to flow into the second air passage 93. The combination of these two forces allows the methanol mist to flow into and pass through the second air passage 93 quickly, preventing methanol from adhering to the inner wall of the second air passage 93.

[0059] In some embodiments, please refer to Figure 1 The air blowing line 6 is connected to the output end of the compressor 1. With this configuration, fresh air can be directly pressurized by the compressor 1 and supplied to the air blowing line 6. In other embodiments, a separate compressor for pressurizing air can also be installed at the inlet end of the air blowing line 6 as needed.

[0060] In some embodiments, the methanol engine further includes an exhaust manifold 13, an exhaust pipe 14, a turbine 16, and multiple exhaust ducts 12. Each exhaust duct 12 corresponds to a combustion chamber of a plurality of cylinders 15. The exhaust manifold 13 communicates with each exhaust duct 12 and is also connected to the exhaust pipe 14. The exhaust pipe 14 is connected to the turbine 16, and the turbine 16 is driven by the compressor 1. When the cylinders 15 exhaust gas, the exhaust gas generated by the combustion of methanol in the cylinders 15 is collected in the exhaust manifold 13 through the exhaust ducts 12 and enters the turbine 16 through the exhaust pipe 14 to drive the turbine 16 to rotate. The turbine 16 then drives the compressor 1 to operate, utilizing the energy of the exhaust gas to pressurize the outside fresh air. The exhaust ducts 12 are controlled to open and close via exhaust valves.

[0061] In some embodiments, the methanol engine further includes a second temperature sensor 17 for detecting the air temperature inside the intake duct 9. Preferably, the second temperature sensor 17 is disposed inside the second intake duct 93.

[0062] This embodiment also provides a vehicle including the aforementioned methanol engine. The vehicle further includes a gearbox, a drive shaft, and a drive axle, which are sequentially connected in transmission. The methanol engine is connected to the gearbox, and the drive axle is connected to the wheel ends. This vehicle can effectively improve the vaporization of methanol, operate stably, and increase energy utilization.

[0063] This embodiment also provides a control method for a methanol engine, which is executed by the methanol engine described above.

[0064] Please refer to Figure 3 The control method for this methanol engine includes the following steps.

[0065] S100: Obtain engine speed and torque.

[0066] The engine speed can be detected by a speed sensor, and the engine torque can be detected by a torque sensor.

[0067] S110: Determine the engine's motion load based on the engine's speed and torque.

[0068] 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.

[0069] S120: Determine the airflow rate of the intake manifold 9, the airflow rate of the hot air inlet 11, and the target pressure within the cylinder 15 based on the engine's motion load.

[0070] The airflow rate of intake duct 9 is the flow rate of cold air entering intake duct 9 from intake manifold 5. The airflow rate of hot air inlet 11 is the flow rate of hot air entering intake duct 9 through hot air inlet 11. Specifically, the memory pre-stores a second correspondence between the engine's operating load and the airflow rates of intake duct 9 and hot air inlet 11. Based on the engine's operating load and the second correspondence, the airflow rates of intake duct 9 and hot air inlet 11 can be determined. The second correspondence can be determined through extensive prior experiments.

[0071] Specifically, the memory pre-stores a third correspondence between the engine's operating load and the target pressure within cylinder 15. Based on the engine's operating load and the third correspondence, the target pressure within cylinder 15 can be determined. The third correspondence can be determined through extensive prior experiments.

[0072] S130: Determine the first initial opening of the throttle valve 4 based on the airflow in the intake manifold 9.

[0073] With the compressor 1 rotating at a constant speed, the opening of the throttle valve 4 directly determines the flow rate of air delivered from the compressor 1 to the intake manifold 5, and thus determines the flow rate of cold air delivered from the intake manifold 5 to each intake duct 9.

[0074] Specifically, the memory pre-stores a fourth correspondence between the airflow of the intake manifold 9 and the first initial opening of the throttle valve 4. The first initial opening of the throttle valve 4 can be determined based on the airflow of the intake manifold 9 and the fourth correspondence. The fourth correspondence can be determined through extensive prior experiments.

[0075] S140: Determine the second initial opening degree of control valve 8 based on the air flow rate of hot air inlet 11.

[0076] With the compressor 1 rotating at a constant speed, the opening of the control valve 8 directly determines the flow rate of air delivered from the compressor 1 to the blowing line 6, and thus determines the flow rate of hot air delivered from the blowing line 6 to each intake duct 9.

[0077] Specifically, the memory pre-stores a fifth correspondence between the air flow rate of the hot air inlet 11 and the second initial opening degree of the control valve 8. The second initial opening degree of the control valve 8 can be determined based on the air flow rate of the hot air inlet 11 and the fifth correspondence. The fifth correspondence can be determined through extensive prior experiments.

[0078] S150: Methanol injection parameters are determined based on the airflow rate of intake duct 9 and the airflow rate of hot air inlet 11.

[0079] The methanol injection parameters include the methanol injection quantity, the opening phase angle of the methanol injector 10, and the closing phase angle of the methanol injector 10. It can be understood that both the opening and closing phase angles of the methanol injector 10 correspond to the phase angle of the crankshaft. As the crankshaft rotates, its phase angle changes continuously. When the crankshaft's phase angle equals the opening phase angle of the methanol injector 10, the methanol injector 10 begins to inject methanol. When the crankshaft's limiting angle equals the closing phase angle of the methanol injector 10, the methanol injector 10 closes. Therefore, the opening and closing phase angles of the methanol injector 10 determine the methanol injection duration. Based on the methanol injection quantity and the methanol injection duration, the methanol injection quantity per unit time can be determined.

[0080] Specifically, the memory pre-stores a sixth correspondence between the air flow rate of the intake duct 9, the air flow rate of the hot air inlet 11, and the methanol injection parameters. The methanol injection parameters can be determined based on the air flow rate of the intake duct 9, the air flow rate of the hot air inlet 11, and the sixth correspondence. The sixth correspondence can be obtained through extensive prior experiments.

[0081] Step S150 allows the methanol injection parameters to be matched with the airflow rate of the intake manifold 9 and the airflow rate of the hot air inlet 11, ensuring sufficient vaporization and combustion of methanol within the cylinder 15. Furthermore, the engine's operating load is primarily determined by both the airflow rate of the intake cylinder 15 and the injected methanol. Step S150 also ensures that the methanol injection parameters, the airflow rate of the intake manifold 9 and the airflow rate of the hot air inlet 11, and the engine's operating load are interconnected, thereby satisfying the engine's operating load requirements.

[0082] S160: Determine the first target temperature of the heating element 7 based on the methanol injection parameters.

[0083] By using the methanol injection parameters, the total heat required for methanol vaporization and the heat required per unit time can be determined. This allows us to determine the temperature at which the air in the blowing pipe 6 needs to be heated, i.e., the first target temperature, given the current air flow rate at the hot air inlet 11.

[0084] Specifically, the memory pre-stores a seventh correspondence between the methanol injection parameters and the first target temperature of the heating element 7. The first target temperature of the heating element 7 can be determined by the methanol injection parameters and the seventh correspondence. The seventh correspondence can be obtained through a large number of previous experiments.

[0085] S170: When the phase angle of the crankshaft is equal to the opening phase angle of the methanol injector 10, the methanol injector 10 starts to inject methanol based on the methanol injection parameters, and adjusts the throttle valve 4 to the first initial opening, adjusts the control valve 8 to the second initial opening, and adjusts the temperature of the heating element 7 to the first target temperature.

[0086] Step S170 enables the methanol injector 10 to inject methanol, and in the initial stage of methanol injection, the throttle valve 4 is matched with the first initial opening, the control valve 8 is matched with the second initial opening, and the heating element 7 is matched with the first target temperature, which can theoretically meet the current engine's operating load requirements, while also ensuring that the methanol is fully vaporized and fully combusted.

[0087] When the methanol injector 10 injects methanol based on the methanol injection parameters, the injection duration of the methanol injector 10 is equal to the time difference between the opening phase angle and the closing phase angle of the methanol injector 10, the amount of methanol injected by the methanol injector 10 is equal to the methanol injection quantity, and the pressure of the methanol injected by the methanol injector 10 remains stable.

[0088] S180: Obtain the actual pressure inside cylinder 15, and adjust the opening of throttle valve 4 and control valve 8 based on the difference between target pressure and actual pressure until the difference between target pressure and actual pressure is within the set range.

[0089] The actual pressure inside cylinder 15 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 its own components, such as performance degradation due to prolonged use. This can easily lead to situations where, if the throttle valve 4 maintains its first initial opening, the control valve 8 maintains its second initial opening, and the heating element 7 maintains its first target temperature, the engine's operating load may not meet expectations. Step S180 effectively mitigates this issue.

[0090] The pressure inside cylinder 15 directly determines the total amount of air and methanol mixture in the cylinder. When the actual pressure inside the cylinder 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.

[0091] Specifically, please refer to Figure 4 Step S180 includes the following steps S181-S186:

[0092] S181: Obtain the actual pressure inside cylinder 15 and calculate the difference between the actual pressure and the target pressure.

[0093] S182: Determine whether the difference exceeds the upper limit of the set range.

[0094] If yes, then execute S183; otherwise, execute S184.

[0095] S183: Increase the opening of throttle valve 4 by the first set value, decrease the opening of control valve 8 by the second set value, and return to step S181.

[0096] S184: Determine whether the difference exceeds the lower limit of the set range.

[0097] If yes, then execute S185; otherwise, execute S186.

[0098] S185: Decrease the opening of throttle valve 4 by the third setting value, and increase the opening of control valve 8 by the fourth setting value.

[0099] S186: Determine that the difference between the target pressure and the actual pressure is within the set range.

[0100] Through steps S181 to S186, the air pressure inside cylinder 15 can be stabilized to the target pressure to meet the engine's operating load.

[0101] S190: When the phase angle of the crankshaft is equal to the closing phase angle of the methanol injector 10, the methanol injector 10 stops injecting methanol.

[0102] The methanol engine control method provided in this embodiment, through the above steps S100 to S190, can ensure the full vaporization and combustion of methanol while meeting the engine's operating load.

[0103] In an alternative embodiment, please refer to Figure 5 The control method for a methanol engine also includes the following steps between steps S150 and S160.

[0104] S151: Determine the second target temperature of the heating element 7, the opening phase angle of the control valve 8, the closing phase angle of the control valve 8, and the third initial opening degree of the control valve 8 based on the methanol injection quantity.

[0105] In this embodiment, the closing phase angle of the control valve 8 is advanced compared to the opening phase angle of the methanol injector 10. This example demonstrates a scheme where the closing phase angle of the solenoid valve is 30°CA advanced relative to the opening phase angle of the methanol injector.

[0106] Specifically, the memory pre-sets an eighth correspondence between the methanol injection rate and the second target temperature, the opening phase angle of control valve 8, and the closing phase angle of control valve 8. Based on the methanol injection rate and the eighth correspondence, the second target temperature, the opening phase angle of control valve 8, the closing phase angle of control valve 8, and the third initial opening degree of control valve 8 are determined. The eighth correspondence can be obtained through extensive prior experiments.

[0107] In this embodiment, the opening phase angle and the closing phase angle of the control valve 8 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 control valve 8, the control valve 8 opens to the third initial opening degree, and the heating element 7 starts heating. When the limit angle of the crankshaft is equal to the closing phase angle of the control valve 8, the control valve 8 closes and the heating element 7 stops heating.

[0108] S152: When the phase angle of the crankshaft is equal to the opening phase angle of the control valve 8, the control valve 8 is adjusted to the third initial opening, the heating element 7 is turned on, and the temperature of the heating element 7 is adjusted to the third initial temperature.

[0109] Since the closing phase angle of control valve 8 is earlier than the opening phase angle of methanol injector 10, that is, control valve 8 opens before methanol injector 10 injects, allowing hot air in the blowing pipe 6 to enter the intake duct 9, which can preheat the inner wall of the intake duct 9. As a result, when methanol injector 10 is opened later, the intake duct 9 has a higher temperature, so that the inner wall of the intake duct 9 does not need to absorb heat from the hot air entering the intake duct 9. This allows the heat of the hot air to be absorbed by methanol vaporization as much as possible, improving the utilization rate of hot air and ensuring the vaporization effect in the initial stage of methanol injection.

[0110] S153: When the phase angle of the crankshaft is equal to the closing phase angle of the control valve 8, the control valve 8 and the heating element 7 are closed.

[0111] 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.

[0112] 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.

[0113] 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 compressor (1), an intake pipe (2), an intercooler (3), a throttle valve (4), an intake manifold (5), and a plurality of intake components, wherein the compressor (1), the intake pipe (2), and the intake manifold (5) are connected in sequence, the intercooler (3) and the throttle valve (4) are both disposed on the intake pipe (2), and the throttle valve (4) is located between the intercooler (3) and the intake manifold (5), the intake components comprising an intake passage (9) and a methanol injector (10) disposed in the intake passage (9), and the intake manifold (5) is connected to each of the intake passages (9); characterized in that, The methanol engine also includes an air blowing pipe (6), a heating element (7) and a control valve (8) both disposed in the air blowing pipe (6), the air intake assembly also includes a hot air inlet (11) connected to the air intake duct (9), the first end of the air blowing pipe (6) is connected to each of the hot air inlets (11), the second end of the air blowing pipe (6) is used to introduce fresh air, the opening of the control valve (8) is adjustable, and the control valve (8) is used to adjust the flow rate of the air blowing pipe (6).

2. The methanol engine according to claim 1, characterized in that, Along the flow direction of the airflow in the air intake (9), the hot air inlet (11) is located downstream of the methanol injector (10).

3. The methanol engine according to claim 2, characterized in that, The hot air inlet (11) is opened at an angle upward, and the airflow injected through the hot air inlet (11) can provide an upward force to the methanol injected by the methanol injector (10).

4. The methanol engine according to claim 2, characterized in that, The centerline of the air intake (9), the centerline of the methanol injector (10), and the centerline of the hot air inlet (11) intersect at a single point.

5. The methanol engine according to claim 4, characterized in that, The air intake (9) includes a first air intake (91), a first arc-shaped air intake (92), a second air intake (93), a second arc-shaped air intake (94), and a third air intake (95) connected in sequence at an angle. The first air intake (91) is connected to the main air intake pipe (5), and the air intake valve passes through the third air intake (95). The air intake valve is used to open or close the third air intake (95). The methanol injector (10) and the hot air inlet (11) are both located in the first arc-shaped air passage (92), and the center line of the methanol injector (10) is directed toward the center of the end of the first arc-shaped air passage (92) that is connected to the second air passage (93).

6. The methanol engine according to claim 4, characterized in that, The angle between the centerline of the air intake (9) and the centerline of the methanol injector (10) is an acute angle, and the angle between the centerline of the hot air inlet (11) and the centerline of the methanol injector (10) is an acute angle.

7. The methanol engine according to any one of claims 1-6, characterized in that, The blowing pipe (6) is connected to the output end of the compressor (1).

8. A vehicle, characterized in that, The vehicle includes the methanol engine according to any one of claims 1-7, 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.

9. A control method for a methanol engine, characterized in that, The methanol engine, as described in any one of claims 1-7, comprises a control method for the methanol engine including: Obtain the engine speed and torque; The engine's motion load is determined based on the engine's speed and torque; The airflow rate of the intake manifold (9), the airflow rate of the hot air inlet (11), and the target pressure in the cylinder (15) are determined based on the motion load of the engine. The first initial opening of the throttle valve (4) is determined based on the airflow in the intake manifold (9); The second initial opening degree of the control valve (8) is determined based on the air flow rate at the hot air inlet (11); The methanol injection parameters are determined based on the air flow rate of the intake duct (9) and the air flow rate of the hot air inlet (11). The methanol injection parameters include the methanol injection quantity, the opening phase angle of the methanol injector (10), and the closing phase angle of the methanol injector (10). The first target temperature of the heating element (7) is determined based on the methanol injection parameters; When the phase angle of the crankshaft is equal to the opening phase angle of the methanol injector (10), the methanol injector (10) starts to inject methanol based on the methanol injection parameters, and adjusts the throttle valve (4) to the first initial opening, adjusts the control valve (8) to the second initial opening, and adjusts the temperature of the heating element (7) to the first target temperature. Obtain the actual pressure inside the cylinder (15), and adjust the opening of the throttle valve (4) and the opening of the control valve (8) based on the difference between the target pressure and the actual pressure until the difference between the target pressure and the actual pressure is within the set range; When the phase angle of the crankshaft is equal to the closing phase angle of the methanol injector (10), the methanol injector (10) stops injecting methanol.

10. The control method for a methanol engine according to claim 9, characterized in that, It also includes the determination of methanol injection parameters based on the airflow rate of the intake duct (9) and the airflow rate of the hot air inlet (11), and the determination of the first target temperature of the heating element (7) based on the methanol injection quantity: The second target temperature of the heating element (7), the opening phase angle of the control valve (8), the closing phase angle of the control valve (8) and the third initial opening degree of the control valve (8) are determined based on the amount of methanol injected, wherein the closing phase angle of the control valve (8) is earlier than the opening phase angle of the methanol injector (10). When the phase angle of the crankshaft is equal to the opening phase angle of the control valve (8), the control valve (8) is adjusted to the third initial opening, the heating element (7) is turned on and the temperature of the heating element (7) is adjusted to the third initial temperature; When the phase angle of the crankshaft is equal to the closing phase angle of the control valve (8), the control valve (8) and the heating element (7) are closed.

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