A magnetic-electric coupling heated methanol engine cold start device

Abstract

The application belongs to the technical field of power equipment and methanol cold start, and particularly relates to a magnetic-electric coupling heating methanol engine cold start device, which comprises a methanol preheating unit, an air preheating unit, an air inlet unit and an ECU electronic control unit. The methanol preheating unit comprises a methanol tank, a methanol magnetic heating device and an oil sprayer which are sequentially connected through a methanol pipeline. The air preheating unit comprises an air filter and an air heating device which are sequentially connected through an air pipeline. The air heating device and the oil sprayer are in communication with each other and are connected with the air inlet unit. The air heating device comprises a straight-flow preheating flow channel and a plurality of rotational-flow preheating flow channels which are arranged around the straight-flow preheating flow channel. The electronic control unit is electrically connected with the methanol preheating unit and the air preheating unit. The methanol magnetic heating device saves heating time and is beneficial to subsequent methanol droplet atomization, thereby solving the problem of engine cold start difficulty.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power equipment and methanol cold start, and particularly relates to a magnetic-electric coupling heating methanol engine cold start device. BACKGROUND

[0002] In order to cope with the severe situation of energy crisis, efficient use of energy and exploration of clean and renewable energy are very important. Methanol, as a new type of clean fuel, can replace gasoline and diesel oil and be used for many power equipment, which is particularly obvious in motor vehicles. At the same time, as a good carrier of hydrogen, methanol has low boiling point, low cost, high octane value and similar physical and chemical properties to gasoline, making it a favorable candidate for sustainable fuel. With the increasingly wide use of methanol in the field of motor vehicles, its problems have gradually emerged, and the cold start difficulty caused by the high methanol vaporization latent heat is one of the important problems faced by methanol engines. At present, technical researchers alleviate the negative effects of methanol cold start through air intake preheating, fuel preheating and improving fuel spray effect, etc.

[0003] In the prior art, the method of using air intake preheating technology to solve methanol cold start is mostly used. For example, the utility model patent with the authorization announcement number CN220667695U discloses an air intake preheating structure of a methanol engine cold start system, which achieves good preheating effect by using two-section air intake pipes and heating fins directly contacting with air, which is feasible in principle and convenient for disassembly, assembly and maintenance, but the direct heating of the heating fins in the air intake increases the air intake resistance. When the air intake resistance caused by the heating fins in the air intake needs to be overcome, higher air intake pressure is required, but in actual situation, it is difficult to provide high air intake pressure during cold start. In order to better solve the problem of methanol cold start, it is necessary to provide an effective methanol engine cold start magnetic-electric coupling air intake and fuel double preheating device. SUMMARY

[0004] The purpose of the present application is to provide a magnetic-electric coupling heating methanol engine cold start device, which uses a cyclone and straight flow combined air heating device near the air intake methanol injector, can increase the air intake pressure while ensuring the sufficient heat exchange area of the heating fins and the entering air, improve the air temperature uniformity, and the methanol magnetic heating device not only saves the heating time, but also is beneficial to the subsequent methanol droplet atomization, solving the problem of engine cold start difficulty.

[0005] To achieve the above purpose, the present application provides a magnetic-electric coupling heating methanol engine cold start device, which comprises a methanol preheating unit, an air preheating unit, an air intake unit and an ECU electronic control unit.

[0006] The methanol preheating unit comprises a methanol tank, a methanol magnetic heating device and an oil injector connected in sequence through a methanol pipeline.

[0007] The air preheating unit comprises an air filter and an air heating device connected in sequence through an air pipeline; the air heating device and the oil injector are in communication with each other and are connected with the air inlet unit; the air heating device comprises a straight-flow preheating flow channel and a plurality of rotational-flow preheating flow channels arranged around the straight-flow preheating flow channel.

[0008] The ECU electronic control unit is electrically connected with the methanol preheating unit and the air preheating unit respectively.

[0009] Further, the straight-flow preheating flow channel is a hollow cylindrical heating body, and the rotational-flow preheating flow channel comprises a circular heat-insulating peripheral wall and a plurality of rotational-flow wall surfaces, the rotational-flow wall surfaces being uniformly distributed between the inner wall of the circular heat-insulating peripheral wall and the outer wall of the hollow cylindrical heating body to form a plurality of the rotational-flow preheating flow channels.

[0010] Further, the hollow cylindrical heating body and the rotational-flow wall surfaces are PCT heaters.

[0011] Further, the air preheating unit further comprises an air flow meter arranged between the air filter and the air heating device and a temperature sensor arranged between the air heating device and the oil injector.

[0012] Further, the methanol magnetic heating device comprises a methanol flow-around inner pipeline, a methanol flow-around sleeve, a heat-conducting material, a coil and an iron core.

[0013] The coil is wound on the iron core, the methanol flow-around sleeve is wound on the outer wall of the coil, and the methanol flow-around inner pipeline is wrapped in the interior of the methanol flow-around sleeve; one end of the methanol flow-around inner pipeline is connected with the methanol tank, and the other end is connected with the oil injector.

[0014] Further, the heat-conducting material is preferably magnesia.

[0015] Further, magnetic particles are added to the methanol liquid flowing through the methanol magnetic heating device to promote the breaking of methanol droplets under the action of a magnetic field.

[0016] Further, the methanol preheating unit further comprises a temperature sensor, a methanol pump, a filter screen, a methanol flow meter and a flame arrester arranged in sequence between the methanol magnetic heating device and the oil injector, the flame arrester being used to prevent the methanol from being overheated to form methanol vapor and backfire at the nozzle.

[0017] Further, the ECU electronic control unit controls the temperature of the methanol and air at 30-50 DEG C through temperature monitoring of the temperature sensor.

[0018] Further, the intake unit comprises an intake valve and a cylinder, and the preheated air and methanol enter the cylinder after mixing in front of the intake valve.

[0019] Overall, compared with the prior art, the above technical scheme conceived by the present application mainly has the following technical advantages:

[0020] 1. The magnetic-electric coupling heating methanol engine cold start device provided by the present application can increase the intake air pressure while ensuring sufficient heat exchange area between the heating sheet and the entering air, improve the air temperature uniformity, and save the heating time to meet the requirements of different working conditions of the methanol engine, which is beneficial to the subsequent methanol droplet atomization and solves the problem of engine cold start difficulty. The coupling of the two heating effects increases the stability, economy and success rate of methanol cold start.

[0021] 2. The flow-around methanol pipeline designed in the present application can increase the contact time of methanol fuel with the heating wall surface, and the magnesia has good heat conduction performance and low cost. Since the magnetic heating speed is very fast, direct heating will affect the mechanical properties of the pipeline and is difficult to control, so the magnesia can quickly heat the internal methanol while protecting the methanol pipeline. At the same time, the magnetic heater saves the actual heating time and promotes the atomization effect of methanol fuel. In addition, the flow-around pipeline saves the occupied space of the device while ensuring sufficient preheating.

[0022] 3. The air heating device is designed as a PTC spiral heating sheet and a PTC cylindrical heating body. The spiral structure can increase the intake air pressure while ensuring sufficient heat exchange area between the heating sheet and the entering air. The straight intake duct in the middle cylindrical part reduces the use of materials and the intake air pressure burden. At the outlet end of the PTC heating device, the generated spiral preheated air and straight preheated air can be fully mixed and heat each other, ensuring the uniformity of the air temperature in the intake duct, preventing the mechanical stress from increasing due to uneven temperature in the intake pipeline and possibly causing cracks to make the mechanical properties decrease.

[0023] 4. In the case of using magnetic heating, magnetic particles are added to the methanol liquid flowing through the methanol magnetic heating device, so that under the action of the magnetic field, the surface charge distribution and flow characteristics of the methanol droplets are changed, thereby promoting the breaking of the methanol droplets. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is the overall structure schematic diagram of the magnetic-electric coupling heating methanol engine cold start device provided by the present application.

[0025] Figure 2 is a structural schematic diagram of the air heating device of the present application.

[0026] Figure 3 is a structural schematic diagram of the methanol magnetic heating device of the present application.

[0027] In all the drawings, the same reference signs are used to represent the same elements or structures, wherein:

[0028] 1 - power supply; 2 - ECU electronic control unit; 3 - line; 4 - methanol tank; 5 - temperature sensor; 6 - methanol pump; 7 - filter screen; 8 - methanol flowmeter; 9 - flame arrester; 10 - air filter; 11 - air pipeline; 12 - air flowmeter; 13 - fuel injector; 14 - intake valve;

[0029] 30 - air heating device; 31 - heat insulation layer; 32 - cyclone PTC heating sheet; 33 - cylindrical PTC heating body; 34 - cyclone preheating flow channel; 35 - straight flow preheating flow channel;

[0030] 300 - methanol magnetic heating device; 301 - methanol flow-pipe inner pipeline; 302 - heat-conducting material; 303 - methanol flow-pipe sleeve; 304 - coil; 305 - iron core. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the present application more clear, the present application is further described in detail below in combination with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0032] As shown in Figures 1 to 3 , the magnetic-electric coupling methanol cold start device of the embodiment of the present application comprises a methanol preheating unit, an air preheating unit, an intake unit and an ECU electronic control unit 2.

[0033] The methanol preheating unit comprises a methanol tank 4, a methanol magnetic heating device 300 and a fuel injector 13 connected in sequence through a methanol pipeline;

[0034] The air preheating unit comprises an air filter 10 and an air heating device 30 connected in sequence through an air pipeline 11; the air heating device 30 and the fuel injector 13 are in communication with each other and are both connected with the intake unit; the air heating device 30 comprises a straight flow preheating flow channel 35 and a plurality of cyclone preheating flow channels 34 arranged around the straight flow preheating flow channel 35;

[0035] The intake unit includes an intake valve 14 and a cylinder. Preheated air and methanol are mixed at the front end of the intake valve 14 and then enter the cylinder.

[0036] The ECU electronic control unit 2 is electrically connected to the methanol preheating unit and the air preheating unit via line 3.

[0037] This configuration allows the swirling preheating channel 34 to increase intake pressure while promoting uniform mixing of the swirling gas. It also mitigates pressure loss caused by the heating device within the intake manifold, preventing increased mechanical stress and potential cracking due to uneven temperature distribution, thus reducing the mechanical properties of the intake pipe. The swirling gas also helps to impact and break up methanol droplets at the injection point, improving subsequent engine efficiency. Using a magnetic heating system in the fuel (methanol) supply system, compared to traditional preheating methods, not only saves heating time to meet the needs of different methanol engine operating conditions but also facilitates subsequent methanol droplet atomization. Furthermore, the surrounding channel ensures sufficient preheating while saving space.

[0038] Specifically, such as Figure 2 The DC preheating channel 35 is a hollow cylindrical heating element. Figure 2 The hollow cylindrical PTC heating element 33, wherein the swirling preheating flow 34 includes a circular heat-insulating peripheral wall sleeved on the outside of the hollow cylindrical heating element. Figure 2 The middle insulation layer 31) and several swirling wall surfaces ( Figure 2 The PTC heating element 32 is a swirling PTC heater. The swirling wall surface is evenly distributed between the inner wall of the circular heat-insulating peripheral wall and the outer wall of the hollow cylindrical heating body, forming several swirling preheating channels 34 (e.g., 4-8, preferably 6). Both the hollow cylindrical heating body and the swirling wall surface are PCT heaters. Specifically, the swirling PTC heating element 32 is bent at 30° (i.e., the angle of inclination with the radial plane of the hollow cylindrical heating body). The swirling structure ensures sufficient heat exchange area between the heating element and the incoming air while increasing the intake pressure. The straight intake channel in the middle cylindrical section reduces material usage and intake pressure burden. At the outlet end of the PTC heating device, the generated swirling preheating air and direct preheating air can be fully mixed and mutually heat-transferred, ensuring uniform air temperature throughout the intake channel and preventing increased mechanical stress and potential cracking in the intake pipe due to uneven temperature, thus reducing its mechanical properties.

[0039] Specifically, the air preheating unit also includes an air flow meter 12 disposed between the air filter 10 and the air heating device 30, and a temperature sensor 5 disposed between the air heating device 30 and the fuel injector 13. One end of the air pipe 11 is connected to the engine air filter 10, and the other end is connected to the intake valve 14.

[0040] The air flow meter 12 is used to detect the air flow of the air pipe, and in combination with the methanol flow meter 8, the air-fuel ratio can be controlled. The PTC air heating device 30 is used to heat the air passing through the air filter 10. The air here can be mixed with a small amount of carbon monoxide and hydrogen, which is beneficial to the combustion of methanol droplets in the cylinder, so as to achieve better combustion effect and improve the power of the engine. The preheating temperature range of the air is 30-50℃, which is fed back by the rear temperature sensor 5 and controlled by the ECU electronic control unit 2. Compared with magnetic heating, PTC has more stable heating effect and easier temperature control.

[0041] The PTC heating device 30 is arranged near the oil sprayer 13 of the air pipe 11, i.e. at the front end of the oil sprayer 13. The air enters from the air filter 10, is detected by the air flow meter 12, and is heated by the PTC heating device 30 at the same time in the cyclone and straight flow, so as to reach the target preheating temperature. At the same time, the preheated air and the preheated methanol fuel are mixed together in front of the intake valve 14 and enter the cylinder. The preheated air is used to keep the subsequent atomized methanol warm.

[0042] After the air enters from the air filter 10, it passes through the PTC heating device 30. The air is heated in two parts at the same time by the cyclone preheating flow channel 34 and the straight flow preheating flow channel 35. The PTC heating device 30 is arranged near the oil sprayer 13 to ensure that the air is at the target preheating temperature in the air pipe 11 before reaching the oil sprayer 13.

[0043] Specifically, as shown in Figure 1 and Figure 2 , the air passes through the cyclone preheating flow channel 34 and contacts the cyclone PTC heating sheet 32. Sufficient preheating contact area reduces the length requirement of the heating system, saving cost. The design of the cyclone preheating flow channel 34 increases the intake pressure, solving the problem of pressure obstruction caused by the built-in heater of the intake passage. The air passes through the straight flow preheating flow channel 35, which not only saves the cost of materials required in the middle part, but also ensures sufficient preheating of the air while reducing pressure loss.

[0044] Specifically, as shown in Figure 1 and Figure 2 , part of the air is heated by the cyclone PTC heating sheet 32 through the cyclone preheating flow channel 34, and part of the air is heated by the cylindrical PTC heating body 33 through the straight flow preheating flow channel 35. The two parts are preheated at the same time. At the outlet of the PTC heating device, the generated straight flow preheated air can be impacted by the cyclone preheated air and uniformly mixed and heat exchanged with each other, ensuring the uniformity of the preheated air temperature and reducing the possibility of cracks and mechanical property degradation of the intake passage caused by uneven temperature. At the same time, the cyclone preheated air is also beneficial to the breaking and atomization of methanol droplets.

[0045] Please refer to Figure 1 and 3, one end of the methanol flow pipe 301 is connected with the methanol tank 4, and the other end is connected with the methanol pump 6, the liquid methanol is heated to become liquid methanol with a certain temperature after passing through the methanol magnetic heating device 300, and the temperature is monitored in real time by the temperature sensor 5 and fed back to the ECU electronic control unit 2, so as to control the temperature range of 30-50℃. The methanol magnetic heating device 300 is used for heating the methanol liquid, and the magnetic heating speed responds very quickly, which can achieve the purpose of preheating the methanol in a very short time. The preheated methanol fuel filters out the residue (impurities in the methanol) through the filter screen 7, and the real-time flow can be reflected by the subsequent methanol flow meter 8, and the real-time data of the air flow meter 12 can achieve the purpose of controlling the fuel-air ratio. When the ECU electronic control unit 2 is damaged and cannot control the magnetic heating temperature, the flame arrester 9 can prevent the methanol temperature from being too high to form methanol vapor and backfire at the nozzle.

[0046] Specifically, as shown in Figure 1 , the methanol magnetic heating device 300 is arranged in the fuel supply system, and the methanol is extracted by the methanol pump 6, preheated by the methanol magnetic heating device 300, and then sprayed and atomized in the intake port through the subsequent methanol pipeline to the oil sprayer 13.

[0047] Specifically, as shown in Figure 1 and Figure 3 , the methanol fuel is extracted by the methanol pump 6, filtered through the filter screen 7 after being heated by the methanol magnetic heating device 300, and sprayed and atomized in the oil sprayer 13.

[0048] The coil 304 is wound on the iron core 305, and heat energy is generated by electromagnetic induction to heat the methanol fuel passing through the methanol flow inner pipe 301. The methanol fuel is preheated by the methanol flow inner pipe 301, which is arranged as a flow pipe to fully heat the peripheral liquid methanol, and the flow formed in the pipe can uniformly mix the inner layer methanol with the outer layer methanol, achieving the effect of internal heat exchange.

[0049] The methanol flow pipe sleeve 303 is directly in contact with the magnetic heating coil 304, and considering that the heating coil 304 has a very fast temperature response which leads to excessive heating, magnesium oxide sand is added as a heat conducting material 302 between the methanol flow pipe sleeve 303 and the methanol flow inner pipe 301. Magnesium oxide sand has good heat conduction performance and low cost. Because the magnetic heating speed is very fast, direct heating can affect the mechanical properties of the pipeline and is difficult to control, so the magnesium oxide sand can quickly heat the inner flow of methanol while protecting the methanol pipeline.

[0050] Particularly, in the case of magnetic heating, magnetic particles are added to the methanol liquid flowing through the methanol magnetic heating device, for changing the surface charge distribution and flow characteristics of the methanol droplets under the action of the magnetic field, and further promoting the breaking of the methanol droplets. The magnetic particles can be fixed on the filter screen by setting the filter screen in the methanol flow inner pipeline 301, so as to prevent the influence of the magnetic particles flowing with the methanol liquid.

[0051] The response speed of magnetic heating is much faster than that of PTC heating, so that the target preheating temperature can be reached in a very short time, and the magnetism is beneficial to the breaking of the droplets, and provides an auxiliary effect for the subsequent rapid atomization and reduction of the atomization particle size of the methanol fuel after being injected through the oil injector 13.

[0052] Therefore, the working principle of the embodiment of the present application is as follows, and the whole application is divided into a PTC air heating stage, a methanol fuel heating stage and a premixing stage:

[0053] The PTC air heating stage: the air enters the air pipeline 11 through the air filter 10, measures the flow through the air flow meter 12, and then enters the PTC heating section. The PTC heating device 30 preheats the air in two parts of cyclone and straight flow at the same time, and feedback control is performed through the temperature sensor 5 to ensure that the air temperature is maintained at 30-50℃.

[0054] The methanol fuel heating stage: the methanol fuel is extracted by the methanol pump 6 and enters the methanol magnetic heating device 300 for flow preheating. Feedback control is performed through the temperature sensor 5 to maintain the temperature at 30-50°, the preheated methanol fuel is filtered through the filter screen 7 to remove solid impurities, and then enters the oil injector 13 for high-pressure atomization injection after measuring the flow through the methanol flow meter 8.

[0055] The premixing stage: the atomized methanol droplets obtained by the oil injector 13 are mixed with the preheated air composition for further breaking, and then enter the cylinder through the intake valve 14 for combustion.

[0056] Those skilled in the art will readily understand that the above description is only a preferred embodiment of the present application, and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A magnetic-electric coupling heated methanol engine cold start device, characterized in that, The methanol preheating unit, the air preheating unit, the intake unit and the ECU electronic control unit are included. The methanol preheating unit includes a methanol tank, a methanol magnetic heating device and an oil injector connected in sequence through a methanol pipeline. The air preheating unit includes an air filter and an air heating device connected in sequence through an air pipeline; the air heating device and the oil injector are in communication with each other and are connected with the intake unit; the air heating device includes a straight-flow preheating flow channel and a plurality of rotational-flow preheating flow channels arranged around the straight-flow preheating flow channel. The ECU electronic control unit is electrically connected with the methanol preheating unit and the air preheating unit respectively. The methanol magnetic heating device includes a methanol flow-around inner pipeline, a methanol flow-around pipeline sleeve, a heat-conducting material, a coil and an iron core; magnetic particles are added in methanol liquid flowing through the methanol magnetic heating device to promote the breaking of methanol liquid drops under the action of a magnetic field; the magnetic particles are fixed on a filter screen by setting the filter screen in the methanol flow-around inner pipeline to prevent the influence of the magnetic particles flowing with the methanol liquid.

2. The magnetic-electric coupled heated methanol engine cold start device of claim 1, wherein, The straight-flow preheating flow channel is a hollow cylindrical heating body, and the rotational-flow preheating flow channel includes a circular heat-insulating peripheral wall and a plurality of rotational-flow wall surfaces arranged around the hollow cylindrical heating body; the rotational-flow wall surfaces are uniformly distributed between the inner wall of the circular heat-insulating peripheral wall and the outer wall of the hollow cylindrical heating body to form a plurality of the rotational-flow preheating flow channels.

3. The magnetic-electric coupled heated methanol engine cold start device of claim 2, wherein, The hollow cylindrical heating body and the rotational-flow wall surfaces are PTC heaters.

4. The magnetic-electric coupling heated cold start device for a methanol engine according to any one of claims 1 to 3, characterized in that, The air preheating unit further includes an air flow meter arranged between the air filter and the air heating device and a temperature sensor arranged between the air heating device and the oil injector.

5. The magnetic-electric coupled heated methanol engine cold start device of claim 1, wherein, The coil is wound on the iron core, the methanol flow-around pipeline sleeve is wound on the outer wall of the coil, and the methanol flow-around inner pipeline is wrapped inside the methanol flow-around pipeline sleeve; one end of the methanol flow-around inner pipeline is connected with the methanol tank, and the other end is connected with the oil injector.

6. The magnetic-electric coupled heated methanol engine cold start device of claim 5, wherein, The methanol flow-around pipeline sleeve and the methanol flow-around inner pipeline are filled with a heat-conducting material, and the heat-conducting material is magnesia sand.

7. The magnetic-electric coupled heated methanol engine cold start device of claim 1, wherein, The methanol preheating unit further includes a temperature sensor, a methanol pump, a filter screen, a methanol flow meter and a flame arrester arranged in sequence between the methanol magnetic heating device and the oil injector; the flame arrester is used to prevent the methanol from being overheated to form methanol vapor and backfire at the nozzle.

8. The magnetic-electric coupled heated methanol engine cold start device of claim 1, wherein, The ECU electronic control unit controls the temperature of the methanol and air to be 30-50℃ through temperature monitoring of the temperature sensor.

9. The magnetic-electric coupled heated methanol engine cold start device of claim 1, wherein, The intake unit includes an intake valve and a cylinder; the preheated air and methanol are mixed before the intake valve and then enter the cylinder.

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