Methanol engine, vehicle and control method of methanol engine

Abstract

The present application relates to the technical field of vehicles, and specifically discloses a methanol engine, a vehicle and a control method of the methanol engine, the methanol engine comprising a compressor, an air inlet pipe, an intercooler, a throttle valve, an air inlet manifold, a blowing pipeline, a heating element, a control valve and a plurality of air inlet assemblies, the air inlet pipe being connected between an output end of the compressor and the air inlet manifold, the intercooler and the throttle valve both being arranged in the air inlet pipe, and the throttle valve being located between the intercooler and the air inlet manifold; the air inlet assembly comprising an air inlet channel, a methanol injector arranged in the air inlet channel, and a hot air inlet communicated with the air inlet channel, the air inlet manifold being connected with each air inlet channel, the blowing pipeline being used for introducing fresh air and being communicated with each hot air inlet, the heating element and the control valve both being arranged in the blowing pipeline, the heating element being used for heating the fresh air flowing through the blowing pipeline, and the control valve being adjustable in opening degree and being used for adjusting the flow capacity of the blowing pipeline, so that the engine can be ensured to operate normally and the energy utilization rate can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, in particular to a methanol engine, a vehicle and a control method of the methanol engine. BACKGROUND

[0002] The internal combustion engine uses methanol as fuel, which can improve the consumption capacity of renewable energy and is an important measure to significantly reduce the emissions of engine nitrogen oxides and particulate matters. However, due to the high latent heat of methanol, a large amount of heat is absorbed during the evaporation process, which will cause the temperature of the working medium and the wall surface in the intake port to decrease significantly, and will bring two adverse effects: first, the temperature gradient of the intake port wall surface increases, which causes part of the methanol fuel to form a liquid film on the wall surface of the intake port, resulting in unstable amount of gaseous methanol participating in the combustion reaction; second, the change of the thermodynamic state of the working medium causes the change of the in-cylinder temperature field, which affects the stability of in-cylinder combustion.

[0003] In order to solve the above problems, in the related art, the temperature of the air entering the intake manifold is increased, and the air is distributed to each intake port through the intake manifold, so that the methanol is mixed with the air with higher temperature in the intake port more uniformly, and the methanol is prevented from adhering to the wall surface of the intake port. In the related art, the following methods are mainly used to increase the temperature of the air entering the intake manifold: such as the methanol fuel engine intake pipe system disclosed in the prior patent CN200710023316.2, which directly heats the fresh air passing through the air compressor by electricity, and then sends the heated air to the intake manifold; or such as the intake preheating system of the methanol engine disclosed in the prior patent CN202421424370.3, which recycles a part of the exhaust gas and mixes it with the fresh air before sending it to the intake manifold; or such as the methanol engine intake control system disclosed in the prior patent with the application number CN202010305734.6, which divides the fresh air passing through the air compressor into two parts, one part passes through the intercooler, and the other part does not pass through the intercooler, and then the two parts are mixed and sent to the intake manifold.

[0004] However, the above scheme will cause the air entering the intake port to have a high temperature, which will affect the amount of air entering the intake port per unit time and affect the normal operation of the engine. In addition, the heat of the air is distributed in the entire intake port, and cannot be concentrated on the wall surface of the intake port where the methanol adheres, which will cause energy waste. SUMMARY

[0005] The purpose of the present application is to provide a methanol engine, a vehicle and a control method of the methanol engine, which can improve the problem of methanol adhering to the wall surface of the intake port, reduce energy waste and ensure the normal operation of the engine.

[0006] In a first aspect, the present application provides a methanol engine, which comprises a compressor, an air intake pipe, an intercooler, a throttle valve, an air intake manifold and a plurality of air intake assemblies, the compressor, the air intake pipe and the air intake manifold are sequentially connected, the intercooler and the throttle valve are both arranged in the air intake pipe, and the throttle valve is located between the intercooler and the air intake manifold, the air intake assembly comprises an air intake passage and a methanol injector arranged in the air intake passage, and the air intake manifold is connected with each air intake passage; the methanol engine further comprises a blowing pipeline, a heating element and a control valve which are both arranged in the blowing pipeline, the air intake assembly further comprises a hot air inlet which communicates with the air intake passage, a first end of the blowing pipeline communicates with each hot air inlet, a second end of the blowing pipeline is used for introducing fresh air, and the opening degree of the control valve is adjustable, and the control valve is used for adjusting the flow capacity of the blowing pipeline.

[0007] As a preferred technical scheme of the methanol engine, the hot air inlet is located downstream of the methanol injector along the flow direction of the airflow in the air intake passage.

[0008] As a preferred technical scheme of the methanol engine, the hot air inlet is obliquely upwardly arranged, and the airflow injected through the hot air inlet can provide upward force to the methanol injected by the methanol injector.

[0009] As a preferred technical scheme of the methanol engine, the center line of the air intake passage, the center line of the methanol injector and the center line of the hot air inlet intersect at one point.

[0010] As a preferred technical scheme of the methanol engine, the air intake passage comprises a first air passage, a first arc-shaped air passage, a second air passage, a second arc-shaped air passage and a third air passage which are sequentially connected at an angle, the first air passage communicates with the air intake manifold, an intake valve penetrates through the third air passage, and the intake valve is used for opening or closing the third air passage.

[0011] The methanol injector and the hot air inlet are both arranged in the first arc-shaped air passage, and the center line of the methanol injector is directed to the center of one end of the first arc-shaped air passage which communicates with the second air passage.

[0012] As a preferred technical scheme of the methanol engine, the angle between the center line of the air intake passage and the center line of the methanol injector is an acute angle, and the angle between the center line of the hot air inlet and the center line of the methanol injector is an acute angle.

[0013] As a preferred technical scheme of the methanol engine, the blowing pipeline communicates with the output end of the compressor.

[0014] In a second aspect, the present application provides a vehicle comprising the methanol engine according to any one of the above-mentioned solutions, and further comprising a gearbox, a transmission shaft and a drive axle connected in sequence, and the methanol engine is connected with the gearbox.

[0015] In a third aspect, the present application provides a control method of a methanol engine, which is executed by the methanol engine according to any one of the above-mentioned solutions, and the control method of the methanol engine comprises:

[0016] obtaining a rotation speed and a torque of the engine;

[0017] determining a motion load of the engine based on the rotation speed and the torque of the engine;

[0018] determining an air flow of an intake passage, an air flow of a hot air inlet and a target pressure in a cylinder based on the motion load of the engine;

[0019] determining a first initial opening degree of a throttle valve based on the air flow of the intake passage;

[0020] determining a second initial opening degree of a control valve based on the air flow of the hot air inlet;

[0021] determining a methanol injection parameter based on the air flow of the intake passage and the air flow of the hot air inlet, the methanol injection parameter comprising a methanol injection amount, an opening phase angle of a methanol injector and a closing phase angle of the methanol injector;

[0022] determining a first target temperature of a heating member based on the methanol injection parameter;

[0023] when the phase angle of the crankshaft is equal to the opening phase angle of the methanol injector, the methanol injector starts to inject the methanol, and the throttle valve is adjusted to the first initial opening degree, the control valve is adjusted to the second initial opening degree, and the temperature of the heating member is adjusted to the first target temperature;

[0024] obtaining an actual pressure in the cylinder, and adjusting the opening degree of the throttle valve and the opening degree of the control valve 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 a set range;

[0025] when the phase angle of the crankshaft is equal to the closing phase angle of the methanol injector, the methanol injector stops injecting the methanol.

[0026] As the preferred technical solution of the control method of the methanol engine, it further comprises, between the step of determining the methanol injection parameter based on the air flow of the intake passage and the air flow of the hot air inlet and the step of determining the first target temperature of the heating member based on the methanol injection amount, the following steps:

[0027] determining a second target temperature of the heating member, an opening phase angle of the control valve, a closing phase angle of the control valve and a third initial opening degree of the control valve based on the injection amount of the methanol, wherein the closing phase angle of the control valve is earlier than the opening phase angle of the methanol injector;

[0028] adjusting the control valve to the third initial opening degree, turning on the heating member and adjusting the temperature of the heating member to the third initial temperature when the phase angle of the crankshaft is equal to the opening phase angle of the control valve;

[0029] turning off the control valve and the heating member when the phase angle of the crankshaft is equal to the closing phase angle of the control valve.

[0030] The present application has the following advantages:

[0031] The present application provides a methanol engine, a vehicle and a control method of the methanol engine. The methanol engine comprises a compressor, an intake pipe, an intercooler, a throttle valve, an intake manifold, a blowing pipeline, a heating member, a control valve and a plurality of intake assemblies. The compressor, the intake pipe and the intake manifold are connected in sequence. The intercooler and the throttle valve are both arranged in the intake pipe, and the throttle valve is located between the intercooler and the intake manifold. The intake assembly comprises an intake passage, a methanol injector arranged in the intake passage and a hot air inlet communicated with the intake passage. The intake manifold is connected with each intake passage. A first end of the blowing pipeline is communicated with each hot air inlet. A second end of the blowing pipeline is used for introducing fresh air. The heating member and the control valve are both arranged in the blowing pipeline. The heating member is used for heating the fresh air flowing through the blowing pipeline. The opening degree of the control valve is adjustable, and the control valve is used for adjusting the flow capacity of the blowing pipeline. Under the action of the compressor, the fresh air from outside is compressed and delivered into the intake pipe, and then heat exchanged when passing through the intercooler, so that the temperature of the air is reduced to become low-temperature air. When the throttle valve is opened, the low-temperature air enters the intake manifold and is then distributed to each intake passage. Since the density of the low-temperature air is relatively high, the intake amount of each intake passage per unit time can be ensured, so that the air and the methanol can be mixed more fully and uniformly, the air supply efficiency to the cylinder is ensured, and the engine can operate more stably. In addition, the fresh air from outside can also be introduced into each intake passage through the blowing pipeline. When passing through the heating member in the blowing pipeline, the fresh air is heated by the heating member to form hot air. The pressure of the hot air is relatively high compared with that of the cold air, so that the hot air can be directly input into the intake passage under the action of the pressure difference, and the hot air can directly provide heat to the methanol in the intake passage, so as to avoid the methanol from adhering to the wall and ensure the stability of the in-cylinder combustion. Compared with the prior art, the hot air is directly delivered into the intake passage, the temperature difference between the hot air and the methanol is larger, the effect of the methanol absorbing heat is better, the energy utilization rate is improved, and the energy waste is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1Structure schematic diagram of the methanol engine in the embodiment of the present application;

[0033] Figure 2 Structure schematic diagram of the methanol engine in the embodiment of the present application;

[0034] Figure 3 First flow chart of the control method of the methanol engine in the embodiment of the present application;

[0035] Figure 4 Second flow chart of the control method of the methanol engine in the embodiment of the present application;

[0036] Figure 5 Third flow chart of the control method of the methanol engine in the embodiment of the present application.

[0037] In the figure:

[0038] 1, compressor; 2, intake pipe; 3, intercooler; 4, throttle valve; 5, intake manifold; 6, blowing pipeline; 7, heating element; 8, control valve; 9, intake port; 91, first air passage; 92, first arc air passage; 93, second air passage; 94, second arc air passage; 95, third air passage; 10, methanol injector; 11, hot air inlet; 12, exhaust port; 13, exhaust manifold; 14, exhaust pipe; 15, cylinder; 16, turbine; 17, second temperature sensor. DETAILED DESCRIPTION

[0039] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0040] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", are only for the purpose of description, and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions, and moreover, the "above", "above" and "above" of the first feature on the second feature include the first feature above and obliquely above the second feature, or only indicate that the first feature is higher than the second feature in horizontal height. The "below", "below" and "below" of the first feature on the second feature include the first feature below and obliquely below the second feature, or only indicate that the first feature is lower than the second feature in horizontal height.

[0041] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0042] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation on the present application.

[0043] For a methanol engine, due to the high latent heat characteristics and large injection amount of methanol, a large amount of heat will be absorbed during the evaporation process, resulting in a significant decrease in the temperature of the working medium and the wall surface inside the intake port, which will cause the temperature gradient of the wall surface of the intake port to increase, causing part of the methanol fuel to form a liquid film on the wall surface of the intake port, resulting in unstable amount of gaseous methanol participating in the combustion reaction, and also causing the change of thermodynamic state of the working medium to cause the change of temperature field in the cylinder, affecting the stability of combustion in the cylinder.

[0044] To this end, in the related art, the temperature of air entering the intake manifold is increased, and the air is distributed to each intake port through the intake manifold, so that the methanol is mixed with air having a higher temperature in the intake port more uniformly, and the methanol is prevented from adhering to the wall surface of the intake port. Among them, the fresh air passing through the air compressor can be heated directly in the intake pipe (the intake pipe is used to deliver the fresh air compressed by the air compressor to the intake manifold, and then distributed to the plurality of intake ports through the intake manifold, and then delivered to the combustion chamber of the corresponding cylinder through the intake port), and the heated air is delivered to the intake manifold to increase the temperature of the air entering the intake manifold; or a part of the exhaust gas is recycled and mixed with the fresh air and then delivered to the intake manifold to increase the temperature of the air entering the intake manifold; or the fresh air passing through the air compressor is divided into two parts, one part passes through the intercooler, and the other part does not pass through the intercooler, and then the two parts are mixed and delivered to the intake manifold to increase the temperature of the air entering the intake manifold. However, these schemes will cause the air temperature entering the intake port to be high, and the density of the air will be relatively reduced, which will affect the amount of air entering the intake port per unit time, and then affect the amount of air entering the combustion chamber of the cylinder, and affect the normal operation of the engine; in addition, the heat of the air is distributed in the entire intake port, and cannot be concentrated on the wall surface of the intake port where the methanol adheres, which will cause energy waste.

[0045] In addition, in the related art, in order to form a liquid film of the wall surface methanol fuel on the wall surface of the intake port, an electric heating device is also provided at a position where the liquid film is easily formed on the wall surface of the intake port, and the electric heating device provides heat to promote vaporization of the methanol, promote evaporation of the methanol in the intake port, and enhance the effect of methanol atomization, thereby improving the in-cylinder combustion stability. Among them, the electric heating device can be arranged outside the intake port, but this will cause a large heat exchange loss; the electric heating device can also be arranged in the intake port, but this will occupy the internal space of the intake port and affect the stability of the intake.

[0046] To this end, in the present embodiment, a methanol engine is provided to solve the above problems. The methanol engine can be applied to vehicles, ships, etc.

[0047] Please refer to Figure 1 and Figure 2The methanol engine comprises a compressor 1, an air inlet pipe 2, an intercooler 3, a throttle valve 4, an air inlet manifold 5, a blowing pipe 6, a heating element 7, a control valve 8 and a plurality of air inlet assemblies. The input end of the compressor 1 is used to introduce fresh air, the air inlet pipe 2 is connected between the output end of the compressor 1 and the air inlet manifold 5, the intercooler 3 and the throttle valve 4 are both arranged in the air inlet pipe 2, and the throttle valve 4 is located between the intercooler 3 and the air inlet manifold 5. The air inlet assembly comprises an air inlet channel 9, a methanol injector 10 arranged in the air inlet channel 9, and a hot air inlet 11 in communication with the air inlet channel 9. The air inlet manifold 5 is connected with each air inlet channel 9. A first end of the blowing pipe 6 is in communication with each hot air inlet 11. A second end of the blowing pipe 6 is used to introduce fresh air. The heating element 7 and the control valve 8 are both arranged in the blowing pipe 6. The heating element 7 is used to heat the fresh air flowing through the blowing pipe 6. The opening degree of the control valve 8 is adjustable, and the control valve 8 is used to adjust the flow capacity of the blowing pipe 6.

[0048] It can be understood that the plurality of air inlet assemblies are used to supply the combustion chambers of the plurality of cylinders 15 with the mixture of air and methanol vapor one by one.

[0049] The methanol engine provided by the embodiment can ensure that the air inlet amount of the air inlet channel 9 per unit time, thereby ensuring that the air and the methanol can be mixed more uniformly, and can also ensure the air supply efficiency of the cylinder 15, so that the engine can operate more stably. In addition, the fresh air from the outside can also be introduced into each air inlet channel 9 through the blowing pipe 6, and the fresh air is heated by the heating element 7 in the blowing pipe 6 to form hot air. The pressure of the hot air is relatively high compared with that of the cold air, so that the hot air can be directly input into the air inlet channel 9 under the action of the pressure difference, and can directly provide heat for the methanol in the air inlet channel 9, thereby avoiding the adhesion of the methanol to the wall, ensuring the stability of the in-cylinder combustion, and compared with the prior art, the hot air is directly input into the air inlet channel 9, the temperature difference between the hot air and the methanol is larger, the effect of absorbing heat by the methanol is better, the energy utilization rate can be improved, and the energy waste can be reduced.

[0050] Preferably, the control valve 8 is an electromagnetic valve, and the heating element 7 is an electric heating wire. In other embodiments, the control valve 8 can also be a hydraulic control valve, and the heating element 7 can also be a heat exchanger.

[0051] In some embodiments, the methanol engine further comprises a first temperature sensor for detecting the temperature of the gas in the blowpipe 6. Preferably, the first temperature sensor is arranged downstream of the heating element 7.

[0052] In some embodiments, referring to Figure 2 , the hot air inlet 11 is arranged downstream of the methanol injector 10 along the flow direction of the airflow in the intake passage 9. Since the methanol mist sprayed by the methanol injector 10 will move downstream under the action of the airflow of the cold air entering the intake passage 9, the methanol mist will adhere to the wall of the intake passage 9 downstream of the methanol injector 10 under the action of gravity, and the wall of the intake passage 9 adhered by the methanol will form a methanol falling area. By arranging the hot air inlet 11 downstream of the methanol injector 10, the hot air transported into the intake passage 9 from the hot air inlet 11 can be closer to or directly act on the methanol mist in the methanol falling area, so that the energy of the hot air can be fully utilized, thereby avoiding methanol adhesion.

[0053] In some embodiments, referring to Figure 2 , the hot air inlet 11 is inclined upward, and the airflow sprayed through the hot air inlet 11 can provide an upward force to the methanol sprayed by the methanol injector 10. By inclining the hot air inlet 11 upward, the methanol mist can be provided with upward power, thereby allowing the methanol mist to stay in the air for a longer time. When the methanol mist is in the air, the heat exchange area with the hot air will be significantly larger than when the methanol adheres to the wall of the intake passage 9, so that the methanol mist can absorb more heat from the hot air sprayed through the hot air inlet 11, thereby facilitating the full vaporization of the methanol to avoid methanol adhesion.

[0054] In some embodiments, referring to Figure 2 , the center line of the intake passage 9, the center line of the methanol injector 10, and the center line of the hot air inlet 11 intersect at one point. By such arrangement, the cold air entering the intake passage 9 from the intake manifold 5 and the hot air entering the intake passage 9 from the hot air inlet 11 meet at the center, and act on the center of the methanol spray, so that the methanol spray is atomized more fully under the impact of the two airflows, thereby more facilitating the full vaporization of the methanol; at the same time, the center of the hot air and the center of the methanol spray meet, which can also make the methanol more efficiently absorb the heat of the hot air.

[0055] In some embodiments, when the cold air entering the intake passage 9 from the intake passage 9, the methanol mist sprayed by the methanol injector 10, and the hot air entering the intake passage 9 from the hot air inlet 11 meet, the cold air entering the intake passage 9 from the intake pipe 2 flows in an obliquely downward direction, the hot air entering the intake passage 9 from the hot air inlet 11 flows in an obliquely upward direction, and the center line of the methanol mist sprayed by the methanol injector 10 flows in a horizontal direction or an obliquely upward direction, so that the mist sprayed by the methanol injector 10 can have a relatively long residence time, thereby further improving the methanol vaporization effect. In the present embodiment, the center line of the methanol mist sprayed by the methanol injector 10 flows in a horizontal direction as an example.

[0056] In some embodiments, referring to Figure 2 , the intake passage 9 comprises a first passage 91, a first arc-shaped passage 92, a second passage 93, a second arc-shaped passage 94, and a third passage 95 connected in sequence at an angle, the first passage 91 is communicated with the intake manifold 5, the intake valve penetrates through the third passage 95, and the intake valve is used to open or close the third passage 95; the methanol injector 10 and the hot air inlet 11 are both arranged in the first arc-shaped passage 92, and the center line of the methanol mist sprayed by the methanol injector 10 is directed to the center of the end of the first arc-shaped passage 92 communicated with the second passage 93. In this way, the cold air contacts the methanol mist only after passing through the first passage 91 and a part of the first arc-shaped passage 92, and the flow direction of the cold air is changed from a straight line to a rotational flow by the first arc-shaped passage 92, so that when the cold air acts on the methanol mist, the methanol mist is not directly blown to the wall surface of the first arc-shaped passage 92 or the second passage 93, but can be blown into the second passage 93, thereby further avoiding the methanol adhesion. Preferably, the extension direction of the second passage 93 is substantially parallel to the direction of the center line of the methanol mist sprayed by the methanol injector 10.

[0057] In other embodiments, the center line of the methanol mist sprayed by the methanol injector 10 can also be higher than the center of the end of the first arc-shaped passage 92 communicated with the second passage 93, so as to increase the height of the relative methanol falling area of the methanol mist, thereby increasing the residence time of the methanol mist, and further improving the methanol vaporization effect.

[0058] In some embodiments, referring to Figure 2, the included angle between the center line of the air inlet 9 and the center line of the methanol injector 10 is an acute angle, and the included angle between the center line of the hot air inlet 11 and the center line of the methanol injector 10 is an acute angle. Specifically, the center line of the first arc-shaped air passage 92 intersects the center line of the methanol injector 10 and the two are at an acute angle, which gives the methanol gas mist a force to flow towards the second air passage 93 when the cold air contacts the methanol gas mist, and also gives the methanol gas mist a force to flow towards the second air passage 93 when the hot air contacts the methanol gas mist, and the two forces are superimposed, so that the methanol gas mist can quickly flow into and through the second air passage 93, avoiding the methanol from adhering to the wall of the second air passage 93.

[0059] In some embodiments, please refer to Figure 1 The air blowing pipeline 6 is in communication with the output end of the air compressor 1. In this way, the fresh air can be directly pressurized by the air compressor 1 and supplied to the air blowing pipeline 6. In other embodiments, a compressor for pressurizing air can also be separately arranged at the inlet end of the air blowing pipeline 6 as needed.

[0060] In some embodiments, the methanol engine further comprises an exhaust manifold 13, an exhaust pipe 14, a turbine 16 and a plurality of exhaust passages 12, the plurality of exhaust passages 12 are arranged one by one corresponding to the combustion chambers of the plurality of cylinders 15, the exhaust manifold 13 is in communication with each of the exhaust passages 12, and the exhaust manifold 13 is in communication with the exhaust pipe 14, the exhaust pipe 14 is connected to the turbine 16, and the turbine 16 is drivingly connected to the air compressor 1. When the cylinders 15 exhaust, the exhaust gas generated by the combustion of methanol in the cylinders 15 is collected through the exhaust passages 12 to the exhaust manifold 13, and enters the turbine 16 through the exhaust pipe 14 to drive the turbine 16 to rotate, and in turn drives the air compressor 1 to work through the turbine 16, so as to pressurize the fresh air outside by using the energy of the exhaust gas. The exhaust passage 12 is controlled to open and close by an exhaust valve.

[0061] In some embodiments, the methanol engine further comprises a second temperature sensor 17 for detecting the temperature of the air in the air inlet 9. Preferably, the second temperature sensor 17 is arranged in the second air passage 93.

[0062] The present embodiment also provides a vehicle comprising the above-mentioned methanol engine, the vehicle further comprising a gearbox, a transmission shaft and a drive axle connected in sequence, the methanol engine being drivingly connected to the gearbox, and the drive axle being drivingly connected to a wheel end. The vehicle can effectively improve the vaporization effect of methanol, run stably, and improve the energy utilization rate.

[0063] The present embodiment also provides a control method of a methanol engine, which is executed by the above-mentioned methanol engine.

[0064] Please refer to Figure 3 The control method of the methanol engine comprises the following steps.

[0065] S100: Obtain the rotation speed and torque of the engine.

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

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

[0068] Specifically, a first correspondence relationship between the rotation speed and torque of the engine and the motion load of the engine is pre-stored in the memory, and the motion load of the engine is determined according to the obtained rotation speed and torque of the engine and the first correspondence relationship. The first correspondence relationship can be determined according to a large number of experiments in advance.

[0069] S120: Determine the air flow of the intake passage 9, the air flow of the hot air inlet 11, and the target pressure in the cylinder 15 based on the motion load of the engine.

[0070] The air flow of the intake passage 9 is the flow of cold air input from the intake manifold 5 to the intake passage 9. The air flow of the hot air inlet 11 is the flow of hot air input to the intake passage 9 through the hot air inlet 11. Specifically, a second correspondence relationship between the motion load of the engine and the air flow of the intake passage 9 and the air flow of the hot air inlet 11 is pre-stored in the memory, and the air flow of the intake passage 9 and the air flow of the hot air inlet 11 can be determined according to the motion load of the engine and the second correspondence relationship. The second correspondence relationship can be determined through a large number of experiments in advance.

[0071] Specifically, a third correspondence relationship between the motion load of the engine and the target pressure in the cylinder 15 is pre-stored in the memory, and the target pressure in the cylinder 15 can be determined according to the motion load of the engine and the third correspondence relationship. The third correspondence relationship can be determined through a large number of experiments in advance.

[0072] S130: Determine the first initial opening degree of the throttle valve 4 based on the air flow of the intake passage 9.

[0073] In the case where the rotation speed of the compressor 1 is constant, the opening degree of the throttle valve 4 directly determines the flow of air delivered to the intake manifold 5 through the compressor 1, and further determines the flow of cold air delivered to each intake passage 9 by the intake manifold 5.

[0074] Specifically, a fourth correspondence relationship between the air flow of the intake passage 9 and the first initial opening degree of the throttle valve 4 is pre-stored in the memory, and the first initial opening degree of the throttle valve 4 can be determined according to the air flow of the intake passage 9 and the fourth correspondence relationship. The fourth correspondence relationship can be determined through a large number of experiments in advance.

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

[0076] With the rotational speed of the compressor 1 being constant, the opening degree of the control valve 8 directly determines the air flow delivered by the compressor 1 to the hot air pipeline 6, and further determines the air flow delivered by the hot air pipeline 6 to each of the intake ports 9.

[0077] Specifically, the memory pre-stores a fifth corresponding relationship between the air flow of the hot air inlet 11 and the second initial opening degree of the control valve 8, and the second initial opening degree of the control valve 8 can be determined according to the air flow of the hot air inlet 11 and the fifth corresponding relationship. The fifth corresponding relationship can be determined through a large number of experiments in advance.

[0078] S150: Determine the injection parameter of the methanol based on the air flow of the intake port 9 and the air flow of the hot air inlet 11.

[0079] The injection parameter of the methanol includes the injection amount of the methanol, the opening phase angle of the methanol injector 10, and the closing phase angle of the methanol injector 10. It can be understood that the opening phase angle of the methanol injector 10 and the closing phase angle of the methanol injector 10 both correspond to the phase angle of the crankshaft. With the rotation of the crankshaft, the phase angle of the crankshaft changes constantly. 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 the methanol. When the phase angle of the crankshaft is equal to the closing phase angle of the methanol injector 10, the methanol injector 10 is closed. Therefore, the opening phase angle of the methanol injector 10 and the closing phase angle of the methanol injector 10 determine the injection duration of the methanol, and the injection amount of the methanol per unit time can be determined according to the injection amount of the methanol and the injection duration of the methanol.

[0080] Specifically, the memory pre-stores a sixth corresponding relationship between the air flow of the intake port 9 and the air flow of the hot air inlet 11 and the injection parameter of the methanol, and the injection parameter of the methanol can be determined according to the air flow of the intake port 9 and the air flow of the hot air inlet 11 and the sixth corresponding relationship. The sixth corresponding relationship can be obtained through a large number of experiments in advance.

[0081] Through step S150, the injection parameter of the methanol can be adapted to the air flow of the intake port 9 and the air flow of the hot air inlet 11, that is, sufficient vaporization and combustion of the methanol in the cylinder 15 can be ensured. In addition, the motion load of the engine is mainly determined by the air flow of the intake cylinder 15 and the injected methanol. Through step S150, the injection parameter of the methanol, the air flow of the intake port 9 and the air flow of the hot air inlet 11, and the motion load of the engine are correlated with each other, and the motion load of the engine is further satisfied.

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

[0083] The injection parameter of the methanol can determine the total heat required for the methanol vaporization, and the heat required per unit time, and then determine the temperature of the air in the air blowing pipeline 6 required to be heated, that is, the first target temperature, under the condition of the current air flow of the air inlet 11.

[0084] Specifically, the seventh corresponding relationship between the injection parameter of the methanol and the first target temperature of the heating element 7 is pre-stored in the memory, and the first target temperature of the heating element 7 can be determined by the injection parameter of the methanol and the seventh corresponding relationship. The seventh corresponding relationship can be obtained by a large number of experiments in advance.

[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 injection parameter of the methanol, 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] Through step S170, the methanol injector 10 can inject methanol, and in the initial stage of the methanol injection, the throttle valve 4 matches the first initial opening, the control valve 8 matches the second initial opening, and the heating element 7 matches the first target temperature, which can theoretically meet the demand of the current engine motion load, and also enable the methanol to be fully vaporized and combusted.

[0087] Wherein, when the methanol injector 10 injects methanol based on the injection parameter of the methanol, the time length of the methanol injection of the methanol injector 10 is equal to the time difference between the opening phase angle of the methanol injector 10 and the closing phase angle of the methanol injector 10, the amount of methanol injected by the methanol injector 10 is equal to the injection amount of the methanol, and the pressure of the methanol injected by the methanol injector 10 remains stable.

[0088] S180: Obtain the actual pressure in 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.

[0089] The actual pressure in the cylinder 15 can be obtained by a pressure sensor. Because in the actual operation process of the methanol engine, it may be affected by external environmental factors such as external temperature, altitude, and its own factors such as performance decline due to long-term use, it is easy to cause the engine motion load to not meet the expectation if the throttle valve 4 remains at the first initial opening, the control valve 8 remains at the second initial opening, and the temperature of the heating element 7 remains at the first target temperature. Through step S180, this phenomenon can be effectively improved.

[0090] The pressure in the cylinder 15 directly determines the total amount of air and methanol mixture in the cylinder. When the actual pressure in the cylinder is equal to the target pressure or the difference between the actual pressure and the target pressure is within the set range, the engine motion load can be reliably satisfied after the in-cylinder combustion work.

[0091] Specifically, referring to Figure 4 , the step S180 includes the following steps S181-S186:

[0092] S181: Obtain the actual pressure in the 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, perform S183; if no, perform S184.

[0095] S183: Increase the opening of the throttle valve 4 by a first set value, decrease the opening of the control valve 8 by a 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, perform S185; if no, perform S186.

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

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

[0100] Through steps S181-S186, the pressure in the cylinder 15 can be stabilized to the target pressure, and the engine motion load can be satisfied.

[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 control method of the methanol engine provided in the embodiment can ensure sufficient vaporization and combustion of methanol under the premise of satisfying the engine motion load through steps S100-S190.

[0103] In an optional embodiment, referring to Figure 5 , the control method of the methanol engine further includes the following steps between step S150 and step S160.

[0104] S151: determining the second target temperature of the heating member 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 injection amount of methanol.

[0105] In this embodiment, the closing phase angle of the control valve 8 is advanced by 30°CA relative to the opening phase angle of the methanol injector 10.

[0106] Specifically, the eighth corresponding relationship between the injection amount of methanol and the second target temperature, the opening phase angle of the control valve 8 and the closing phase angle of the control valve 8 is pre-set in the memory, and the second target temperature, 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 according to the injection amount of methanol and the eighth corresponding relationship. The eighth corresponding relationship can be obtained through a large number of experiments in advance.

[0107] In this embodiment, the opening phase angle of the control valve 8 and the closing phase angle of the control valve 8 both correspond to the phase angle of the crankshaft. With the rotation of the crankshaft, the phase angle of the crankshaft changes constantly, 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 member 7 starts heating, when the phase angle of the crankshaft is equal to the closing phase angle of the control valve 8, the control valve 8 is closed and the heating member 7 stops heating.

[0108] S152: when the phase angle of the crankshaft is equal to the opening phase angle of the control valve 8, adjusting the control valve 8 to the third initial opening degree, starting the heating member 7 and adjusting the temperature of the heating member 7 to the third initial temperature.

[0109] Since the closing phase angle of the control valve 8 is advanced relative to the opening phase angle of the methanol injector 10, that is, the control valve 8 opens before the methanol injector 10, the hot air in the blowing pipeline 6 is introduced into the intake port 9, the inner wall of the intake port 9 can be preheated, and then when the methanol injector 10 is opened subsequently, the intake port 9 has a high temperature, so that the inner wall of the intake port 9 does not need to absorb heat from the hot air entering the intake port 9, so that the heat of the hot air can be absorbed by the methanol vaporization as much as possible, improve the utilization rate of the hot air, and ensure the vaporization effect at 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, closing the control valve 8 and the heating member 7.

[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 air intake pipe (2), an intercooler (3), a throttle valve (4), an air intake manifold (5) and a plurality of air intake assemblies, the compressor (1), the air intake pipe (2) and the air intake manifold (5) being connected in sequence, the intercooler (3) and the throttle valve (4) being arranged in the air intake pipe (2), and the throttle valve (4) being located between the intercooler (3) and the air intake manifold (5), the air intake assembly comprising an air intake passage (9) and a methanol injector (10) arranged in the air intake passage (9), the air intake manifold (5) being connected with each air intake passage (9); characterized in that, The methanol engine further comprises a blowing pipeline (6), and a heating element (7) and a control valve (8) both arranged in the blowing pipeline (6), the air intake assembly further comprises hot air inlets (11) in communication with the air intake passage (9), a first end of the blowing pipeline (6) is in communication with each of the hot air inlets (11), a second end of the blowing pipeline (6) is used for passing fresh air, an opening degree of the control valve (8) is adjustable, and the control valve (8) is used for adjusting a flow capacity of the blowing pipeline (6); The hot air inlets (11) are located downstream of the methanol injectors (10) along a flow direction of airflow in the air intake passage (9); The hot air inlets (11) are obliquely upwardly arranged, and airflow jetted through the hot air inlets (11) can provide upward force to methanol jetted by the methanol injectors (10); The blowing pipeline (6) is in communication with an output end of the compressor (1).

2. The methanol engine according to claim 1, characterized by Center lines of the air intake passage (9), the methanol injectors (10) and the hot air inlets (11) intersect at a point.

3. The methanol engine according to claim 2, characterized by The air intake passage (9) comprises a first air passage (91), a first arc-shaped air passage (92), a second air passage (93), a second arc-shaped air passage (94) and a third air passage (95) sequentially and angularly communicated, the first air passage (91) is in communication with the air intake manifold (5), an intake valve passes through the third air passage (95), and the intake valve is used for opening or closing the third air passage (95); The methanol injectors (10) and the hot air inlets (11) are both arranged in the first arc-shaped air passage (92), and a center line of the methanol injectors (10) is directed to a center of an end of the first arc-shaped air passage (92) in communication with the second air passage (93).

4. The methanol engine according to claim 2, wherein An angle between the center line of the air intake passage (9) and the center line of the methanol injectors (10) is an acute angle, and an angle between the center line of the hot air inlets (11) and the center line of the methanol injectors (10) is an acute angle.

5. A vehicle characterized by comprising: The vehicle further comprises a gearbox, a transmission shaft and a drive axle which are sequentially and drivingly connected, and the methanol engine is drivingly connected with the gearbox.

6. A control method of a methanol engine, characterized by, The control method of the methanol engine comprises: acquiring a rotating speed and a torque of the engine; determining a motion load of the engine based on the rotating speed and the torque of the engine; determining an air flow of the air intake passage (9), an air flow of the hot air inlets (11) and a target pressure in the cylinder (15) based on the motion load of the engine; determining a first initial opening degree of the throttle valve (4) based on the air flow of the air intake passage (9); determining a second initial opening degree of the control valve (8) based on the air flow of the hot air inlets (11); determining injection parameters of the methanol based on the air flow rate of the intake passage (9) and the air flow rate of the hot air inlet (11), the injection parameters of the methanol including an injection amount of the methanol, an opening phase angle of the methanol injector (10), and a closing phase angle of the methanol injector (10); determining a first target temperature of the heating member (7) based on the injection parameters of the methanol; starting injection of the methanol by the methanol injector (10) based on the injection parameters of the methanol when the phase angle of the crankshaft is equal to the opening phase angle of the methanol injector (10), and adjusting the throttle valve (4) to a first initial opening degree, adjusting the control valve (8) to a second initial opening degree, and adjusting the temperature of the heating member (7) to the first target temperature; acquiring an actual pressure in the cylinder (15), and adjusting the opening degree of the throttle valve (4) and the opening degree of the control valve (8) based on a difference between the target pressure and the actual pressure until the difference between the target pressure and the actual pressure is within a set range; stopping the injection of the methanol by the methanol injector (10) when the phase angle of the crankshaft is equal to the closing phase angle of the methanol injector (10).

7. The control method of a methanol engine according to claim 6, characterized by, Further comprising, between the determining of the injection parameters of the methanol based on the air flow rate of the intake passage (9) and the air flow rate of the hot air inlet (11) and the determining of the first target temperature of the heating member (7) based on the injection parameters of the methanol: determining a second target temperature of the heating member (7), an opening phase angle of the control valve (8), a closing phase angle of the control valve (8), and a third initial opening degree of the control valve (8) based on the injection amount of the methanol, wherein the closing phase angle of the control valve (8) is earlier than the opening phase angle of the methanol injector (10); adjusting the control valve (8) to the third initial opening degree when the phase angle of the crankshaft is equal to the opening phase angle of the control valve (8), turning on the heating member (7), and adjusting the temperature of the heating member (7) to a third initial temperature; turning off the control valve (8) and the heating member (7) when the phase angle of the crankshaft is equal to the closing phase angle of the control valve (8).

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