Methanol engine control method and device and methanol engine system

Abstract

The invention provides a methanol engine control method and device and a methanol engine system. The method comprises the steps that the required vaporization heat exchange amount, the actual wall surface temperature of the gas inlet channel and the flow to be introduced are obtained, the required vaporization heat exchange amount is the heat exchange amount required by vaporization of methanol to be introduced into the gas inlet channel in the gas inlet channel, and the flow to be introduced is the flow of the methanol to be introduced into the gas inlet channel; according to the required vaporization heat exchange amount, the actual wall surface temperature and the preset methanol specific heat capacity, the heat exchange temperature difference is determined to be the ratio of the required vaporization heat exchange amount to a preset product, and the preset product is the product of the methanol specific heat capacity and the to-be-introduced flow; determining the wall surface required temperature of the air inlet channel as the sum of the heat exchange temperature difference and the wall surface actual temperature; and the first valve is controlled to be opened to the preset opening degree at least according to the wall face required temperature, waste gas in the exhaust channel enters the gas channel, the wall face of the gas inlet channel is heated, and the actual temperature of the heated wall face reaches the wall face required temperature.

Description

Technical Field

[0001] The present application relates to the field of engine control, and in particular, to a control method and device for a methanol engine, a computer-readable storage medium, and a methanol engine system. Background Art

[0002] In the methanol multi-point injection system, the injection structure injects methanol fuel into the intake duct of each cylinder of the engine, and then mixes with fresh air and enters the fuel in the cylinder. Because the atomization temperature of methanol is relatively low (boiling point 63.8℃), it is easy for the injected methanol to contact the wall of the intake duct and cool down, affecting combustion. Summary of the invention

[0003] The main purpose of the present application is to provide a control method, device, computer-readable storage medium and methanol engine system for a methanol engine, so as to at least solve the problem in the prior art that methanol fuel of a methanol engine is atomized in the intake duct, thereby affecting the combustion efficiency.

[0004] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a control method for a methanol engine is provided, wherein the methanol engine comprises an intake duct, an exhaust duct, a first valve and a heating chamber, wherein the intake duct is used to introduce air and methanol; the exhaust duct is used to discharge exhaust gas; the heating chamber has a accommodating space, the intake duct is located in the accommodating space, a gas channel is formed between the intake duct and the inner wall of the heating chamber, the inlet of the gas channel is connected to the exhaust duct through the first valve, and the method comprises: obtaining a required vaporization heat exchange amount, an actual wall temperature of the intake duct and a flow rate to be introduced, wherein the required vaporization heat exchange amount is the heat exchange amount required for the methanol to be introduced into the intake duct to vaporize in the intake duct, and the flow rate to be introduced is the amount of heat to be introduced into the intake duct. the flow rate of the methanol in the inlet duct; determining the heat exchange temperature difference as the ratio of the required vaporization heat exchange amount to a predetermined product according to the required vaporization heat exchange amount, the flow rate to be introduced and the preset specific heat capacity of methanol, the predetermined product being the product of the specific heat capacity of methanol and the flow rate to be introduced; determining the required wall temperature of the inlet duct as the sum of the heat exchange temperature difference and the actual wall temperature, the required wall temperature being the wall temperature of the inlet duct required for vaporizing the methanol introduced into the inlet duct; at least according to the required wall temperature, controlling the first valve to open to a predetermined opening, so that the exhaust gas in the exhaust duct enters the gas channel, and heating the wall of the inlet duct so that the actual wall temperature after heating reaches the required wall temperature.

[0005] Optionally, at least according to the required wall temperature, the first valve is controlled to open to a predetermined opening, including: determining the required exhaust gas flow rate according to the required wall temperature, the exhaust flow rate of the exhaust duct and the exhaust temperature of the exhaust duct; determining the predetermined opening degree according to the required exhaust gas flow rate; controlling the first valve to open to the predetermined opening degree so that the exhaust gas passes into the heating chamber at the required exhaust gas flow rate.

[0006] Optionally, obtaining the required vaporization heat exchange amount includes: obtaining the current temperature of the methanol to be introduced into the intake duct; determining the temperature rise heat exchange amount of the methanol to be introduced into the intake duct as J1=c1Q according to the specific heat capacity of the methanol, the flow rate to be introduced, the preset methanol vaporization temperature and the current temperature. me (t2-t1), J1 is the heating heat, c1 is the specific heat capacity of methanol, Q me is the flow rate to be introduced, t2 is the methanol vaporization temperature, and t1 is the current temperature; according to the flow rate to be introduced and the preset methanol vaporization heat, the vaporization heat exchange amount of the methanol to be introduced into the inlet duct is determined to be J2=Q me r, J2 is the vaporization heat exchange, r is the methanol vaporization heat; according to the heating heat exchange and the vaporization heat exchange, the required vaporization heat exchange is determined to be the sum of the heating heat exchange and the vaporization heat exchange.

[0007] Optionally, obtaining the actual temperature of the wall of the intake duct includes: obtaining the intake temperature of the intake duct, the outer diameter of the pipe of the intake duct, the wall thickness of the intake duct, the mass of the exhaust gas in the heating chamber, and the temperature difference of the exhaust gas at the inlet and outlet of the heating chamber; determining the exchange heat between the exhaust gas and the wall as J3=c2mΔt according to the exhaust gas temperature difference, the exhaust gas mass and the preset exhaust gas specific heat capacity, where J3 is the exchange heat, c2 is the exhaust gas specific heat capacity, m is the exhaust gas mass, and Δt is the exhaust gas temperature difference; determining the actual wall temperature as T=T according to the intake temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient. in +aJ3 / (Dσ), T is the actual wall temperature, T in is the intake air temperature, a is the convection heat transfer coefficient, D is the pipe outer diameter, and σ is the wall thickness.

[0008] Optionally, according to the inlet air temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient, the actual wall temperature is determined to be T=T in+aJ3 / (Dσ), before controlling the first valve to open to a predetermined opening at least according to the required wall temperature, the method further includes: correcting the actual wall temperature according to the actual vehicle speed of the vehicle where the methanol engine is located and the current ambient temperature to obtain a corrected actual wall temperature, and controlling the first valve to open to a predetermined opening at least according to the required wall temperature, including: controlling the first valve to open to the predetermined opening at least according to the corrected actual wall temperature.

[0009] Optionally, the actual wall temperature is corrected according to the actual vehicle speed and the current ambient temperature of the vehicle where the methanol engine is located to obtain a corrected actual wall temperature, including: according to the actual vehicle speed, the current ambient temperature and a predetermined relationship, determining that the wall temperature correction value of the methanol engine corresponding to the actual vehicle speed and the current ambient temperature in the predetermined relationship is a target temperature, and the predetermined relationship is a correspondence between the vehicle speed, the ambient temperature and the wall temperature correction value; according to the actual wall temperature and the target temperature, determining that the corrected actual wall temperature is the difference between the actual wall temperature and the target temperature.

[0010] Optionally, the outlet of the gas channel is connected to the exhaust duct through a second valve, and the method further includes: when it is detected that the outlet temperature of the gas channel is lower than a predetermined temperature, controlling the second valve to open so that at least part of the exhaust gas in the heating chamber flows into the exhaust duct.

[0011] According to another aspect of the present application, a control device for a methanol engine is provided, the methanol engine comprising an intake duct, an exhaust duct, a first valve and a heating chamber, the intake duct being used for introducing air and methanol; the exhaust duct being used for discharging exhaust gas; the heating chamber having a accommodating space, the intake duct being located in the accommodating space, a gas channel being formed between the intake duct and an inner wall of the heating chamber, the inlet of the gas channel being connected to the exhaust duct through the first valve, the device comprising: an acquisition unit for acquiring a required vaporization heat exchange amount, an actual wall temperature of the intake duct and a flow rate to be introduced, the required vaporization heat exchange amount being the heat exchange amount required for vaporization of the methanol to be introduced into the intake duct in the intake duct, the flow rate to be introduced being the flow rate of the methanol to be introduced into the intake duct; a first valve for obtaining a required vaporization heat exchange amount, an actual wall temperature of the intake duct and a flow rate to be introduced A determination unit, used to determine the heat exchange temperature difference as the ratio of the required vaporization heat exchange amount to a predetermined product according to the required vaporization heat exchange amount, the flow rate to be introduced and the preset specific heat capacity of methanol, wherein the predetermined product is the product of the specific heat capacity of methanol and the flow rate to be introduced; a second determination unit, used to determine the required wall temperature of the intake duct as the sum of the heat exchange temperature difference and the actual wall temperature, wherein the required wall temperature is the wall temperature of the intake duct required for vaporizing the methanol introduced into the intake duct; a first control unit, used to control the first valve to open to a predetermined opening at least according to the required wall temperature, so that the exhaust gas in the exhaust duct enters the gas channel, and heats the wall of the intake duct so that the actual wall temperature after heating reaches the required wall temperature.

[0012] According to another aspect of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute any one of the methods described.

[0013] According to another aspect of the present application, a methanol engine system is provided, comprising: a methanol engine, comprising an intake duct, an exhaust duct, a first valve and a heating chamber, wherein the intake duct is used to introduce air and methanol; the exhaust duct is used to discharge exhaust gas; the heating chamber has a accommodating space, the intake duct is located in the accommodating space, a gas channel is formed between the intake duct and the inner wall of the heating chamber, and the inlet of the gas channel is connected to the exhaust duct through the first valve; a controller of the methanol engine, comprising one or more processors, a memory and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include methods for executing any one of the described methods.

[0014] By applying the technical solution of the present application, the required vaporization heat exchange amount of methanol, the actual wall temperature of the intake duct and the flow rate of methanol to be introduced are first obtained; then, the heat exchange temperature difference is determined by the endothermic formula according to the required vaporization heat exchange amount, the flow rate to be introduced and the preset specific heat capacity of methanol; then, the required wall temperature of the intake duct is determined according to the actual wall temperature and the obtained heat exchange temperature difference; finally, at least according to the required wall temperature, the first valve between the exhaust duct and the heating chamber is controlled to open to a predetermined opening, so that the exhaust gas discharged from the exhaust duct enters the gas channel to heat the wall of the intake duct, so that the actual temperature of the heated wall reaches the required wall temperature. The heating chamber of the present application surrounds the air inlet duct, so that a gas channel exists between the heating chamber and the air inlet duct, and the required wall temperature required for vaporizing the injected methanol is determined based on the required vaporization heat exchange amount of methanol, the specific heat capacity of methanol, the amount of methanol to be introduced and the actual wall temperature of the air inlet duct, and then the opening of the first valve between the gas channel inlet and the exhaust duct is controlled at least based on the required wall temperature, so that the exhaust gas in the exhaust duct enters the gas channel and preheats the wall of the air inlet duct, so that the actual wall temperature reaches the required wall temperature, thereby avoiding the problem of low air inlet temperature, methanol injected therein contacting the air inlet duct wall and atomizing and attaching to the wall, resulting in low combustion efficiency, and ensuring sufficient combustion of methanol. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings constituting part of the present application are used to provide a further understanding of the present application. The exemplary embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0016] Figure 1 A hardware structure block diagram of a mobile terminal for executing a method for controlling a methanol engine provided in an embodiment of the present application is shown;

[0017] Figure 2 A structural schematic diagram of a methanol engine provided in an embodiment of the present application is shown;

[0018] Figure 3 A schematic flow chart of a method for controlling a methanol engine according to an embodiment of the present application is shown;

[0019] Figure 4 A schematic flow chart of another method for controlling a methanol engine according to an embodiment of the present application is shown;

[0020] Figure 5 A schematic flow chart of another method for controlling a methanol engine according to an embodiment of the present application is shown;

[0021] Figure 6 A structural block diagram of a methanol engine control device provided according to an embodiment of the present application is shown.

[0022] The drawings include the following reference numerals:

[0023] 102. Processor; 104. Memory; 106. Transmission device; 108. Input / output device; 10. Intake duct; 11. Exhaust duct; 12. First valve; 13. Heating chamber; 14. Gas channel; 15. Supercharger; 16. Intercooler; 17. Exhaust pipe; 18. Exhaust tail pipe; 19. First temperature sensor; 20. Second temperature sensor. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0026] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the accompanying drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0027] As introduced in the background technology, the methanol fuel of the methanol engine in the prior art is atomized in the intake duct, affecting the combustion efficiency. To solve the above technical problems, the embodiments of the present application provide a control method, device, computer-readable storage medium and methanol engine system for a methanol engine.

[0028] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0029] The method embodiments provided in the embodiments of the present application can be executed in a mobile terminal, a computer terminal or a similar computing device. Taking running on a mobile terminal as an example, Figure 1 FIG. 1 is a hardware structure block diagram of a mobile terminal of a method for controlling a methanol engine according to an embodiment of the present invention. Figure 1 As shown, the mobile terminal may include one or more ( Figure 1 Only one is shown in the figure) a processor 102 (the processor 102 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 for storing data, wherein the mobile terminal may also include a transmission device 106 and an input / output device 108 for communication functions. It can be understood by those skilled in the art that Figure 1 The structure shown is for illustration only and does not limit the structure of the mobile terminal. Figure 1 More or fewer components as shown, or with Figure 1 Different configurations are shown.

[0030] The memory 104 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the control method of the methanol engine in the embodiment of the present invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, that is, the method described is implemented. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories may be connected to the mobile terminal via a network. Examples of the network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof. The transmission device 106 is used to receive or send data via a network. The specific example of the network may include a wireless network provided by a communication provider of the mobile terminal. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, referred to as NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 106 may be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0031] In this embodiment, a control method for a methanol engine running on a mobile terminal, a computer terminal or a similar computing device is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0032] Figure 2 A partial structural schematic diagram of a methanol engine according to an embodiment of the present application is exemplarily shown, as shown in FIG. Figure 2 As shown, the methanol engine comprises:

[0033] An air intake duct 10, wherein the air intake duct 10 is used to introduce air and methanol;

[0034] Specifically, the intake passage 10 is an intake pipe, and may also be referred to as an intake manifold.

[0035] An exhaust passage 11, wherein the exhaust passage 11 is used to discharge exhaust gas;

[0036] A first valve 12;

[0037] Specifically, the first valve 12 may be an exhaust butterfly valve, or other types of valve structures.

[0038] The heating chamber 13 has a containing space, the air inlet 10 is located in the containing space, a gas channel 14 is formed between the air inlet 10 and the inner wall of the heating chamber 13, and the inlet of the gas channel 14 is connected to the exhaust channel 11 through the first valve 12.

[0039] Specifically, the inlet of the gas channel 14 is the inlet of the heating chamber 13, and the outlet of the gas channel 14 is the outlet of the heating chamber 13. The pipe wall (also called the wall surface) of the air inlet 10 may not contact the inner wall of the heating chamber 13 ( Figure 2 The gas channel 14 completely surrounds the air inlet 10; the pipe wall of the air inlet 10 may also partially contact the inner wall of the heating chamber 13, in which case the gas channel 14 only half surrounds the air inlet 10.

[0040] Figure 3 : is a flow chart of a control method of a methanol engine according to an embodiment of the present application. Figure 3 As shown, the method comprises the following steps:

[0041] Step S201, obtaining a required vaporization heat exchange amount, an actual wall temperature of the intake duct, and a flow rate to be introduced, wherein the required vaporization heat exchange amount is the heat exchange amount required for vaporization of the methanol to be introduced into the intake duct in the intake duct, and the flow rate to be introduced is the flow rate of the methanol to be introduced into the intake duct;

[0042] Specifically, the methanol to be introduced into the intake duct is the methanol to be injected into the intake duct in the next cycle. The wall surface of the intake duct is the pipe wall of the intake duct. The actual wall surface temperature is the actual temperature of the pipe wall. When the actual temperature is lower than or equal to the atomization temperature of the methanol, the methanol injected into the intake duct contacts the wall surface and atomizes.

[0043] Step S202, according to the required vaporization heat transfer amount, the flow rate to be introduced and the preset specific heat capacity of methanol, determining the heat exchange temperature difference as the ratio of the required vaporization heat transfer amount to a predetermined product, wherein the predetermined product is the product of the specific heat capacity of methanol and the flow rate to be introduced;

[0044] Specifically, the specific heat capacity of methanol is a constant at a fixed temperature. The heat exchange temperature difference is the temperature change caused by the vaporization of methanol to be injected into the intake duct in the intake duct, and the heat exchange temperature difference is determined by the heat absorption and release formula.

[0045] Step S203, determining the required wall temperature of the intake duct as the sum of the heat exchange temperature difference and the actual wall temperature, wherein the required wall temperature is the wall temperature of the intake duct required for vaporizing the methanol entering the intake duct;

[0046] Step S204, at least according to the required wall temperature, controlling the first valve to open to a predetermined opening, so that the exhaust gas in the exhaust duct enters the gas channel, and heats the wall of the intake duct so that the actual temperature of the heated wall reaches the required wall temperature.

[0047] Specifically, since the temperature of the exhaust gas discharged from the exhaust duct is generally high, the exhaust gas is passed into the heating chamber and circulated in the gas channel, so that the exhaust gas and the intake duct exchange heat, which has the effect of heating the wall of the intake duct.

[0048] Through the embodiment, the required vaporization heat exchange amount of methanol, the actual wall temperature of the intake duct and the flow rate of methanol to be introduced are first obtained; then, the heat exchange temperature difference is determined by the endothermic and exothermic formula according to the required vaporization heat exchange amount, the flow rate to be introduced and the preset specific heat capacity of methanol; then, the required wall temperature of the intake duct is determined according to the actual wall temperature and the obtained heat exchange temperature difference; finally, at least according to the required wall temperature, the first valve between the exhaust duct and the heating chamber is controlled to open to a predetermined opening, so that the exhaust gas discharged from the exhaust duct enters the gas channel to heat the wall of the intake duct, so that the actual temperature of the heated wall reaches the required wall temperature. The heating chamber of the present application surrounds the air inlet duct, so that a gas channel exists between the heating chamber and the air inlet duct, and the required wall temperature required for vaporizing the injected methanol is determined based on the required vaporization heat exchange amount of methanol, the specific heat capacity of methanol, the amount of methanol to be introduced and the actual wall temperature of the air inlet duct, and then the opening of the first valve between the gas channel inlet and the exhaust duct is controlled at least based on the required wall temperature, so that the exhaust gas in the exhaust duct enters the gas channel and preheats the wall of the air inlet duct, so that the actual wall temperature reaches the required wall temperature, thereby avoiding the problem of low air inlet temperature, methanol injected therein contacting the air inlet duct wall and atomizing and attaching to the wall, resulting in low combustion efficiency, and ensuring sufficient combustion of methanol.

[0049] Specifically, the required wall temperature is generally greater than or equal to 65°C.

[0050] In addition, if Figure 2 As shown, the methanol engine further includes a supercharger 15 and an intercooler 16, the exhaust passage 11 includes an exhaust pipe 17 and an exhaust tail pipe 18, the exhaust tail pipe 18 is connected to the supercharger 15 through the exhaust pipe 17, one end of the intercooler 16 is connected to the intake passage 10, and the other end is connected to the supercharger 15. Fresh air is pressurized by the supercharger 15 and then transported to the intercooler 16 for cooling, and the cooled air is transported to the intake passage 10.

[0051] In one alternative, Figure 4 As shown, step S204: controlling the first valve to open to a predetermined opening degree at least according to the required wall temperature, comprises:

[0052] Step S2041: determining the exhaust gas required flow rate according to the required wall temperature, the exhaust flow rate of the exhaust duct and the exhaust temperature of the exhaust duct;

[0053] Specifically, the exhaust flow rate is the exhaust flow rate of the exhaust gas, the exhaust temperature is the temperature of the exhausted exhaust gas, and the exhaust gas demand flow rate is the exhaust gas flow rate that needs to enter the heating chamber to heat the intake duct.

[0054] Step S2042: determining the predetermined opening according to the exhaust gas demand flow rate;

[0055] Specifically, the exhaust gas demand flow rate is positively correlated with the opening degree of the first valve. The larger the exhaust gas demand flow rate is, the larger the predetermined opening degree is.

[0056] Step S2043: Control the first valve to open to the predetermined opening, so that the exhaust gas flows into the heating chamber at the required exhaust gas flow rate.

[0057] In the described embodiment, the required wall temperature, the exhaust gas emission flow rate and the exhaust gas temperature are comprehensively considered to determine the required exhaust gas flow rate, and then the opening of the first valve is determined according to the required exhaust gas flow rate, so as to control the first valve to open according to the opening, so that the exhaust gas enters the heating chamber at the required exhaust gas flow rate, thereby further realizing the precise control of the heating temperature of the intake duct wall, thereby further ensuring that the intake duct wall is heated to the required wall temperature.

[0058] Furthermore, according to the required wall temperature, the exhaust flow rate of the exhaust duct and the exhaust temperature of the exhaust duct, the specific method for determining the required exhaust gas flow rate can be: establishing a simulation model of the methanol engine, modeling the combustion process, emission process and thermodynamic performance of the methanol engine, and obtaining a correspondence table between the required wall temperature, the exhaust flow rate, the exhaust temperature and the required exhaust gas flow rate; according to the correspondence table and the current required wall temperature, the current exhaust flow rate and the current exhaust temperature, looking up the table to determine the current required exhaust gas flow rate.

[0059] It should be noted that the implementation method of step S204 is not limited to the method described. In an exemplary embodiment, step S204: controlling the first valve to open to a predetermined opening degree at least according to the required wall temperature, may also include: determining the required exhaust gas flow rate according to the required wall temperature; determining the predetermined opening degree according to the required exhaust gas flow rate; controlling the first valve to open to the predetermined opening degree so that the exhaust gas passes into the heating chamber at the required exhaust gas flow rate.

[0060] In a specific application process, the required vaporization heat exchange amount can be determined by calculation or preset. The actual wall temperature can be measured by a temperature sensor set on the wall of the intake duct, or can be determined based on parameters such as the intake temperature of the intake duct and the heat exchange with the exhaust gas. The flow rate of the methanol to be introduced into the intake duct can be determined by the injection flow rate preset by the methanol injection structure, or can be obtained by actual measurement by a flow sensor.

[0061] In some exemplary embodiments of the present application, obtaining the required vaporization heat exchange amount includes: obtaining the current temperature of the methanol to be introduced into the intake duct; determining the heating heat exchange amount of the methanol to be introduced into the intake duct as J1=c1Q according to the specific heat capacity of the methanol, the flow rate to be introduced, the preset methanol vaporization temperature and the current temperature. me (t2-t1), J1 is the heating heat, c1 is the specific heat capacity of methanol, Q me is the flow rate to be introduced, t2 is the methanol vaporization temperature, and t1 is the current temperature; according to the flow rate to be introduced and the preset methanol vaporization heat, the vaporization heat exchange amount of the methanol to be introduced into the inlet duct is determined to be J2=Q me r, J2 is the vaporization heat exchange, r is the vaporization heat of methanol; according to the heating heat exchange and the vaporization heat exchange, the required vaporization heat exchange is determined to be the sum of the heating heat exchange and the vaporization heat exchange. In this embodiment, the heating heat exchange of methanol to be introduced into the intake duct is determined by the heat absorption and release formula, the vaporization heat of methanol is determined by the flow rate of methanol to be introduced and the vaporization heat, and the required vaporization heat exchange is calculated based on these two heats, thereby achieving the effect of accurately and quickly calculating the required vaporization heat exchange, and providing accurate data support for the subsequent opening control of the first valve.

[0062] In actual application, the vaporization heat of methanol is 1109 kJ / kg. The vaporization temperature of methanol is 64.7° C. under standard atmospheric pressure, which can be determined according to the longitude and latitude of the methanol engine.

[0063] The current temperature of the methanol can be acquired by a temperature sensor arranged on the methanol injection mechanism. The methanol injection mechanism generally injects methanol into the intake passage in a cycle, and the flow rate of the methanol to be introduced in each cycle is set, so the set flow rate to be introduced can be directly obtained.

[0064] According to some further optional schemes of the present application, obtaining the actual wall temperature of the intake duct includes: obtaining the intake temperature of the intake duct, the outer diameter of the pipe of the intake duct, the wall thickness of the intake duct, the exhaust gas mass in the heating chamber, and the exhaust gas temperature difference between the inlet and outlet of the heating chamber, wherein the outer diameter of the pipe is the heat transfer surface diameter of the intake duct; determining the exchange heat between the exhaust gas and the wall as J3=c2mΔt according to the exhaust gas temperature difference, the exhaust gas mass, and the preset exhaust gas specific heat capacity, where J3 is the exchange heat, c2 is the exhaust gas specific heat capacity, m is the exhaust gas mass, and Δt is the exhaust gas temperature difference; determining the actual wall temperature as T=T according to the intake temperature, the outer diameter of the pipe, the wall thickness, the exchange heat, and the preset convection heat transfer coefficient. in +aJ3 / (Dσ), T is the actual wall temperature, T inis the intake air temperature, a is the convection heat transfer coefficient, D is the pipe outer diameter, and σ is the wall thickness. This embodiment realizes the real-time calculation of the actual wall temperature, and can obtain a relatively accurate wall temperature, providing accurate data support for the subsequent opening control of the first valve.

[0065] Specifically, the intake air temperature can be acquired by a temperature sensor disposed at the inlet of the intake duct. The outer diameter of the pipe and the wall thickness are both known. Figure 2 As shown, the exhaust gas temperature difference is collected by a first temperature sensor 19 arranged at the inlet of the heating chamber 13 and a second temperature sensor 20 arranged at the outlet of the heating chamber 13. The outlet of the heating chamber is connected to the exhaust duct, so as to discharge the exhaust gas in the heating chamber that has undergone heat exchange with the intake duct to the exhaust duct.

[0066] In order to further ensure the accuracy of the actual wall temperature, and thus further ensure that the subsequent heating of the intake duct wall can be accurately controlled, in some optional embodiments, the actual wall temperature is determined to be T=T according to the intake air temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient. in +aJ3 / (Dσ), before controlling the first valve to open to a predetermined opening at least according to the wall surface required temperature, the method further includes: correcting the actual wall surface temperature according to the actual vehicle speed and current ambient temperature of the vehicle where the methanol engine is located to obtain the corrected actual wall surface temperature, and controlling the first valve to open to a predetermined opening at least according to the wall surface required temperature, including: controlling the first valve to open to the predetermined opening at least according to the corrected actual wall surface temperature. Since the wind during driving will cause a certain amount of heat loss to the intake duct, this embodiment fully considers the influence of the vehicle speed and the current ambient temperature on the actual temperature of the intake duct wall, and corrects the actual wall surface temperature according to the vehicle speed and the ambient temperature, further ensuring that the corrected actual wall surface temperature can more accurately reflect the actual wall surface temperature, thereby further ensuring that the wall surface required temperature determined according to the actual wall surface temperature is more accurate, and further making the subsequent heating control performed according to the wall surface required temperature more accurate.

[0067] Optionally, the actual wall temperature is corrected according to the actual vehicle speed and current ambient temperature of the vehicle in which the methanol engine is located to obtain the corrected actual wall temperature, including: determining the wall temperature correction value of the methanol engine corresponding to the actual vehicle speed and the current ambient temperature in the predetermined relationship as the target temperature according to the actual vehicle speed, the current ambient temperature and a predetermined relationship, wherein the predetermined relationship is a relationship that characterizes the correspondence between the vehicle speed, the ambient temperature and the wall temperature correction value; determining the corrected actual wall temperature as the difference between the actual wall temperature and the target temperature according to the actual wall temperature and the target temperature. Determining the wall temperature correction value corresponding to the current scenario according to the predetermined relationship obtained by pre-calibration further realizes efficient, fast and accurate correction of the actual wall temperature, thereby further ensuring that the corrected actual wall temperature is more accurate and reliable.

[0068] The predetermined relationship may be pre-stored in the local memory in a table form, or in other forms, and the predetermined relationship may be called when needed.

[0069] Alternatively, if Figure 2 As shown, the outlet of the gas channel is connected to the exhaust duct through a second valve (not shown in the figure), and the method further includes: when it is detected that the outlet temperature of the gas channel is less than a predetermined temperature, controlling the second valve to open so that at least part of the exhaust gas in the heating chamber flows into the exhaust duct. When the outlet temperature of the gas channel is low, it means that the exhaust gas here can no longer heat the intake duct. At this time, the exhaust gas with a lower temperature is discharged from the heating chamber, which ensures the stability of the air pressure in the heating chamber and facilitates the introduction of new exhaust gas with a higher temperature into the heating chamber to heat the intake duct.

[0070] Since the density of high-temperature exhaust gas is greater than the density of low-temperature exhaust gas, the inlet height of the heating chamber (i.e., the inlet height of the gas channel) can be set greater than the outlet height of the heating chamber (i.e., the outlet height of the gas channel). In this way, the exhaust gas whose temperature drops after heating the air inlet will sink to the outlet of the heating chamber, thereby making the outlet temperature detection of the gas channel more accurate.

[0071] The type of the second valve may be any suitable valve type, such as a butterfly valve or the like.

[0072] In addition to the electronically controlled valve, the second valve can also be a one-way pressure valve, which does not require control. When the pressure in the heating chamber is high, the second valve automatically opens to discharge a portion of the exhaust gas into the exhaust duct.

[0073] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the implementation process of the methanol engine control method of the present application will be described in detail below in conjunction with specific embodiments.

[0074] This embodiment relates to a Figure 2 The control process of the methanol engine shown in the figure is as follows: Figure 5 As shown, the following steps are included:

[0075] Step S1: determining the required vaporization heat exchange amount of methanol according to the current temperature of methanol and the flow rate to be introduced;

[0076] Step S2: determining the actual wall surface temperature according to the heat exchange between the exhaust gas and the intake duct wall surface and the intake air temperature of the intake duct;

[0077] Step S3: Determine the required wall temperature according to the required vaporization heat exchange amount, the flow rate to be introduced and the actual wall temperature;

[0078] Step S4: determining the exhaust gas required flow rate according to the required wall temperature, the exhaust gas flow rate and the exhaust gas temperature;

[0079] Step S5: Determine a predetermined opening of the valve according to the required exhaust gas flow rate, and open the valve to the predetermined opening.

[0080] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0081] The embodiment of the present application also provides a control device for a methanol engine. It should be noted that the control device for a methanol engine in the embodiment of the present application can be used to execute the control method for a methanol engine provided in the embodiment of the present application. The device is used to implement the embodiments and preferred implementations, and the descriptions that have been made will not be repeated. As used below, the term "module" can implement a combination of software and / or hardware for a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0082] The following is an introduction to the control device of the methanol engine provided in the embodiment of the present application.

[0083] Figure 6 Schematic diagram of a control device for a methanol engine according to an embodiment of the present application. Figure 6 As shown, the device comprises:

[0084] The acquisition unit 100 is used to acquire a required vaporization heat exchange amount, an actual wall temperature of the intake duct, and a flow rate to be introduced, wherein the required vaporization heat exchange amount is the heat exchange amount required for vaporization of the methanol to be introduced into the intake duct in the intake duct, and the flow rate to be introduced is the flow rate of the methanol to be introduced into the intake duct;

[0085] Specifically, the methanol to be introduced into the intake duct is the methanol to be injected into the intake duct in the next cycle. The wall surface of the intake duct is the pipe wall of the intake duct. The actual wall surface temperature is the actual temperature of the pipe wall. When the actual temperature is lower than or equal to the atomization temperature of the methanol, the methanol injected into the intake duct contacts the wall surface and atomizes.

[0086] A first determining unit 200 is used to determine the heat exchange temperature difference as the ratio of the required vaporization heat exchange amount to a predetermined product according to the required vaporization heat exchange amount, the flow rate to be introduced and a preset methanol specific heat capacity, wherein the predetermined product is the product of the methanol specific heat capacity and the flow rate to be introduced;

[0087] Specifically, the specific heat capacity of methanol is a constant at a fixed temperature. The heat exchange temperature difference is the temperature change caused by the vaporization of methanol to be injected into the intake duct in the intake duct, and the heat exchange temperature difference is determined by the heat absorption and release formula.

[0088] A second determining unit 300 is used to determine the required wall temperature of the intake duct as the sum of the heat exchange temperature difference and the actual wall temperature, wherein the required wall temperature is the wall temperature of the intake duct required for vaporizing the methanol entering the intake duct;

[0089] The first control unit 400 is used to control the first valve to open to a predetermined opening degree at least according to the required wall temperature, so that the exhaust gas in the exhaust duct enters the gas channel and heats the wall of the intake duct so that the actual temperature of the heated wall reaches the required wall temperature.

[0090] Specifically, since the temperature of the exhaust gas discharged from the exhaust duct is generally high, the exhaust gas is passed into the heating chamber and circulated in the gas channel, so that the exhaust gas and the intake duct exchange heat, which has the effect of heating the wall of the intake duct.

[0091] Through the described embodiment, the required vaporization heat exchange amount of methanol, the actual wall temperature of the intake duct and the flow rate of methanol to be introduced are obtained through an acquisition unit; the heat exchange temperature difference is determined by the first determination unit according to the required vaporization heat exchange amount, the flow rate to be introduced and the preset specific heat capacity of methanol through the heat absorption and release formula; the required wall temperature of the intake duct is determined by the second determination unit according to the actual wall temperature and the obtained heat exchange temperature difference; the first control unit controls the first valve between the exhaust duct and the heating chamber to open to a predetermined opening at least according to the required wall temperature, so that the exhaust gas discharged from the exhaust duct enters the gas channel to heat the wall of the intake duct, so that the actual temperature of the heated wall reaches the required wall temperature. The heating chamber of the present application surrounds the air inlet duct, so that a gas channel exists between the heating chamber and the air inlet duct, and the required wall temperature required for vaporizing the injected methanol is determined based on the required vaporization heat exchange amount of methanol, the specific heat capacity of methanol, the amount of methanol to be introduced and the actual wall temperature of the air inlet duct, and then the opening of the first valve between the gas channel inlet and the exhaust duct is controlled at least based on the required wall temperature, so that the exhaust gas in the exhaust duct enters the gas channel and preheats the wall of the air inlet duct, so that the actual wall temperature reaches the required wall temperature, thereby avoiding the problem of low air inlet temperature, methanol injected therein contacting the air inlet duct wall and atomizing and attaching to the wall, resulting in low combustion efficiency, and ensuring sufficient combustion of methanol.

[0092] Specifically, the required wall temperature is generally greater than or equal to 65°C.

[0093] In an optional solution, the first control unit includes:

[0094] a first determining module, configured to determine a required exhaust gas flow rate according to the required wall temperature, the exhaust flow rate of the exhaust duct and the exhaust temperature of the exhaust duct;

[0095] Specifically, the exhaust flow rate is the exhaust flow rate of the exhaust gas, the exhaust temperature is the temperature of the exhausted exhaust gas, and the exhaust gas demand flow rate is the exhaust gas flow rate that needs to enter the heating chamber to heat the intake duct.

[0096] A second determination module, configured to determine the predetermined opening degree according to the exhaust gas demand flow rate;

[0097] Specifically, the exhaust gas demand flow rate is positively correlated with the opening degree of the first valve. The larger the exhaust gas demand flow rate is, the larger the predetermined opening degree is.

[0098] The first control module is used to control the first valve to open to the predetermined opening, so that the exhaust gas flows into the heating chamber at the required exhaust gas flow rate.

[0099] In the described embodiment, the required wall temperature, the exhaust gas emission flow rate and the exhaust gas temperature are comprehensively considered to determine the required exhaust gas flow rate, and then the opening of the first valve is determined according to the required exhaust gas flow rate, so as to control the first valve to open according to the opening, so that the exhaust gas enters the heating chamber at the required exhaust gas flow rate, thereby further realizing the precise control of the heating temperature of the intake duct wall, thereby further ensuring that the intake duct wall is heated to the required wall temperature.

[0100] Furthermore, the first determination module includes: an establishment submodule, which is used to establish a simulation model of the methanol engine, model the combustion process, emission process and thermodynamic performance of the methanol engine, and obtain a correspondence table between the required wall temperature, the exhaust flow rate, the exhaust temperature and the exhaust gas required flow rate; a determination submodule, which is used to determine the current exhaust gas required flow rate by looking up the table according to the correspondence table and the current required wall temperature, the current exhaust flow rate and the current exhaust temperature.

[0101] It should be noted that the implementation method of the first control unit is not limited to the method described above. In an exemplary embodiment, the first control unit may also include: a third determination module, used to determine the exhaust gas demand flow rate according to the required wall temperature; a fourth determination module, used to determine the predetermined opening degree according to the exhaust gas demand flow rate; a second control module, used to control the first valve to open to the predetermined opening degree, so that the exhaust gas passes into the heating chamber at the exhaust gas demand flow rate.

[0102] In a specific application process, the required vaporization heat exchange amount can be determined by calculation or preset. The actual wall temperature can be measured by a temperature sensor set on the wall of the intake duct, or can be determined based on parameters such as the intake temperature of the intake duct and the heat exchange with the exhaust gas. The flow rate of the methanol to be introduced into the intake duct can be determined by the injection flow rate preset by the methanol injection structure, or can be obtained by actual measurement by a flow sensor.

[0103] In some exemplary embodiments of the present application, the acquisition unit includes: a first acquisition module for acquiring the current temperature of the methanol to be introduced into the intake duct; a fifth determination module for determining the heating heat of the methanol to be introduced into the intake duct as J1=c1Q according to the specific heat capacity of the methanol, the flow rate to be introduced, the preset methanol vaporization temperature and the current temperature. me (t2-t1), J1 is the heating heat, c1 is the specific heat capacity of methanol, Q me is the flow rate to be introduced, t2 is the methanol vaporization temperature, and t1 is the current temperature; a sixth determination module is used to determine the vaporization heat exchange of the methanol to be introduced into the intake duct according to the flow rate to be introduced and the preset methanol vaporization heat, as J2=Qme r, J2 is the vaporization heat exchange, r is the vaporization heat of methanol; the seventh determination module is used to determine the required vaporization heat exchange as the sum of the heating heat exchange and the vaporization heat exchange according to the heating heat exchange and the vaporization heat exchange. In this embodiment, the heating heat exchange of methanol to be introduced into the intake duct is determined by the heat absorption and release formula, the vaporization heat of methanol is determined by the flow rate of methanol to be introduced and the vaporization heat, and the required vaporization heat exchange is calculated based on these two heats, so as to achieve the effect of accurately and quickly calculating the required vaporization heat exchange, and provide accurate data support for the subsequent opening control of the first valve.

[0104] In actual application, the vaporization heat of methanol is 1109 kJ / kg. The vaporization temperature of methanol is 64.7° C. under standard atmospheric pressure, which can be determined according to the longitude and latitude of the methanol engine.

[0105] The current temperature of the methanol can be acquired by a temperature sensor arranged on the methanol injection mechanism. The methanol injection mechanism generally injects methanol into the intake passage in a cycle, and the flow rate of the methanol to be introduced in each cycle is set, so the set flow rate to be introduced can be directly obtained.

[0106] According to some further optional schemes of the present application, the acquisition unit includes: a second acquisition module, which is used to acquire the intake temperature of the intake duct, the outer diameter of the pipe of the intake duct, the wall thickness of the intake duct, the exhaust gas mass in the heating chamber and the exhaust gas temperature difference between the inlet and outlet of the heating chamber, wherein the outer diameter of the pipe is the diameter of the heat transfer surface of the intake duct; an eighth determination module, which is used to determine the exchange heat between the exhaust gas and the wall as J3=c2mΔt according to the exhaust gas temperature difference, the exhaust gas mass and the preset exhaust gas specific heat capacity, where J3 is the exchange heat, c2 is the exhaust gas specific heat capacity, m is the exhaust gas mass, and Δt is the exhaust gas temperature difference; a ninth determination module, which is used to determine the actual wall temperature as T=T according to the intake temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient. in +aJ3 / (Dσ), T is the actual wall temperature, T in is the intake air temperature, a is the convection heat transfer coefficient, D is the pipe outer diameter, and σ is the wall thickness. This embodiment realizes the real-time calculation of the actual wall temperature, and can obtain a relatively accurate wall temperature, providing accurate data support for the subsequent opening control of the first valve.

[0107] Specifically, the intake air temperature can be acquired by a temperature sensor disposed at the inlet of the intake duct. The outer diameter of the pipe and the wall thickness are both known. The exhaust gas temperature difference is acquired by a temperature sensor disposed at the inlet of the heating chamber and a temperature sensor disposed at the outlet of the heating chamber. The outlet of the heating chamber is connected to the exhaust duct, and is used to discharge the exhaust gas in the heating chamber that has undergone heat exchange with the intake duct to the exhaust duct.

[0108] In order to further ensure the accuracy of the actual wall temperature, and thus further ensure that the subsequent heating of the intake duct wall can be accurately controlled, in some optional embodiments, the device further includes: a correction unit for determining the actual wall temperature as T=T according to the intake air temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient. in +aJ3 / (Dσ), before controlling the first valve to open to a predetermined opening at least according to the wall surface required temperature, the actual wall surface temperature is corrected according to the actual vehicle speed and current ambient temperature of the vehicle where the methanol engine is located to obtain the corrected actual wall surface temperature, and the first control unit includes: a third control module, which is used to control the first valve to open to the predetermined opening at least according to the corrected actual wall surface temperature. Since the wind during driving will cause a certain amount of heat loss to the intake duct, this embodiment fully considers the influence of the vehicle speed and the current ambient temperature on the actual temperature of the intake duct wall, and corrects the actual wall surface temperature according to the vehicle speed and the ambient temperature, further ensuring that the corrected actual wall surface temperature can more accurately reflect the actual wall surface temperature, thereby further ensuring that the wall surface required temperature determined according to the actual wall surface temperature is more accurate, and further making the subsequent heating control performed according to the wall surface required temperature more accurate.

[0109] Optionally, the correction unit includes: a tenth determination module, which is used to determine the wall temperature correction value of the methanol engine corresponding to the actual vehicle speed and the current ambient temperature in the predetermined relationship as the target temperature according to the actual vehicle speed, the current ambient temperature and the predetermined relationship, wherein the predetermined relationship is a corresponding relationship between the vehicle speed, the ambient temperature and the wall temperature correction value; an eleventh determination module, which is used to determine the corrected actual wall temperature as the difference between the actual wall temperature and the target temperature according to the actual wall temperature and the target temperature. The wall temperature correction value corresponding to the current scenario is determined according to the predetermined relationship obtained by pre-calibration, which further realizes efficient, fast and accurate correction of the actual wall temperature, thereby further ensuring that the corrected actual wall temperature is more accurate and reliable.

[0110] The predetermined relationship may be pre-stored in the local memory in a table form, or in other forms, and the predetermined relationship may be called when needed.

[0111] Alternatively, if Figure 2 As shown, the outlet of the gas channel is connected to the exhaust duct through a second valve (not shown in the figure), and the device also includes: a second control unit, which is used to control the second valve to open when it is detected that the outlet temperature of the gas channel is less than a predetermined temperature, so that at least part of the exhaust gas in the heating chamber flows into the exhaust duct. When the outlet temperature of the gas channel is low, it means that the exhaust gas here can no longer heat the intake duct. At this time, the exhaust gas with a lower temperature is discharged from the heating chamber, which ensures the stability of the air pressure in the heating chamber and facilitates the introduction of new exhaust gas with a higher temperature into the heating chamber to heat the intake duct.

[0112] Since the density of high-temperature exhaust gas is greater than the density of low-temperature exhaust gas, the inlet height of the heating chamber (i.e., the inlet height of the gas channel) can be set greater than the outlet height of the heating chamber (i.e., the outlet height of the gas channel). In this way, the exhaust gas whose temperature drops after heating the air inlet will sink to the outlet of the heating chamber, thereby making the outlet temperature detection of the gas channel more accurate.

[0113] The type of the second valve may be any suitable valve type, such as a butterfly valve or the like.

[0114] In addition to the electronically controlled valve, the second valve can also be a one-way pressure valve, which does not require control. When the pressure in the heating chamber is high, the second valve automatically opens to discharge a portion of the exhaust gas into the exhaust duct.

[0115] The control device of the methanol engine includes a processor and a memory, wherein the acquisition unit, the first determination unit, the second determination unit, the first control unit, etc. are all stored in the memory as program units, and the processor executes the program units stored in the memory to implement corresponding functions. The modules are all located in the same processor; or, the modules are located in different processors in any combination.

[0116] The processor includes a kernel, which retrieves the corresponding program unit from the memory. One or more kernels can be provided, and the problem of methanol fuel atomization in the intake duct of the methanol engine in the prior art affecting the combustion efficiency can be at least solved by adjusting the kernel parameters.

[0117] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0118] An embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the control method of the methanol engine.

[0119] Specifically, the control method of the methanol engine includes:

[0120] Step S201, obtaining a required vaporization heat exchange amount, an actual wall temperature of the intake duct, and a flow rate to be introduced, wherein the required vaporization heat exchange amount is the heat exchange amount required for vaporization of the methanol to be introduced into the intake duct in the intake duct, and the flow rate to be introduced is the flow rate of the methanol to be introduced into the intake duct;

[0121] Specifically, the methanol to be introduced into the intake duct is the methanol to be injected into the intake duct in the next cycle. The wall surface of the intake duct is the pipe wall of the intake duct. The actual wall surface temperature is the actual temperature of the pipe wall. When the actual temperature is lower than or equal to the atomization temperature of the methanol, the methanol injected into the intake duct contacts the wall surface and atomizes.

[0122] Step S202, according to the required vaporization heat transfer amount, the flow rate to be introduced and the preset specific heat capacity of methanol, determining the heat exchange temperature difference as the ratio of the required vaporization heat transfer amount to a predetermined product, wherein the predetermined product is the product of the specific heat capacity of methanol and the flow rate to be introduced;

[0123] Specifically, the specific heat capacity of methanol is a constant at a fixed temperature. The heat exchange temperature difference is the temperature change caused by the vaporization of methanol to be injected into the intake duct in the intake duct, and the heat exchange temperature difference is determined by the heat absorption and release formula.

[0124] Step S203, determining the required wall temperature of the intake duct as the sum of the heat exchange temperature difference and the actual wall temperature, wherein the required wall temperature is the wall temperature of the intake duct required for vaporizing the methanol entering the intake duct;

[0125] Step S204, at least according to the required wall temperature, controlling the first valve to open to a predetermined opening, so that the exhaust gas in the exhaust duct enters the gas channel, and heats the wall of the intake duct so that the actual temperature of the heated wall reaches the required wall temperature.

[0126] Specifically, since the temperature of the exhaust gas discharged from the exhaust duct is generally high, the exhaust gas is passed into the heating chamber and circulated in the gas channel, so that the exhaust gas and the intake duct exchange heat, which has the effect of heating the wall of the intake duct.

[0127] Optionally, at least according to the required wall temperature, the first valve is controlled to open to a predetermined opening, including: determining the required exhaust gas flow rate according to the required wall temperature, the exhaust flow rate of the exhaust duct and the exhaust temperature of the exhaust duct; determining the predetermined opening degree according to the required exhaust gas flow rate; controlling the first valve to open to the predetermined opening degree so that the exhaust gas passes into the heating chamber at the required exhaust gas flow rate.

[0128] Optionally, obtaining the required vaporization heat exchange amount includes: obtaining the current temperature of the methanol to be introduced into the intake duct; determining the temperature rise heat exchange amount of the methanol to be introduced into the intake duct as J1=c1Q according to the specific heat capacity of the methanol, the flow rate to be introduced, the preset methanol vaporization temperature and the current temperature. me (t2-t1), J1 is the heating heat, c1 is the specific heat capacity of methanol, Q me is the flow rate to be introduced, t2 is the methanol vaporization temperature, and t1 is the current temperature; according to the flow rate to be introduced and the preset methanol vaporization heat, the vaporization heat exchange amount of the methanol to be introduced into the inlet duct is determined to be J2=Q me r, J2 is the vaporization heat exchange, r is the methanol vaporization heat; according to the heating heat exchange and the vaporization heat exchange, the required vaporization heat exchange is determined to be the sum of the heating heat exchange and the vaporization heat exchange.

[0129] Optionally, obtaining the actual temperature of the wall of the intake duct includes: obtaining the intake temperature of the intake duct, the outer diameter of the pipe of the intake duct, the wall thickness of the intake duct, the mass of the exhaust gas in the heating chamber, and the temperature difference of the exhaust gas at the inlet and outlet of the heating chamber; determining the exchange heat between the exhaust gas and the wall as J3=c2mΔt according to the exhaust gas temperature difference, the exhaust gas mass and the preset exhaust gas specific heat capacity, where J3 is the exchange heat, c2 is the exhaust gas specific heat capacity, m is the exhaust gas mass, and Δt is the exhaust gas temperature difference; determining the actual wall temperature as T=T according to the intake temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient. in +aJ3 / (Dσ), T is the actual wall temperature, T in is the intake air temperature, a is the convection heat transfer coefficient, D is the pipe outer diameter, and σ is the wall thickness.

[0130] Optionally, according to the inlet air temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient, the actual wall temperature is determined to be T=T in+aJ3 / (Dσ), before controlling the first valve to open to a predetermined opening at least according to the required wall temperature, the method further includes: correcting the actual wall temperature according to the actual vehicle speed of the vehicle where the methanol engine is located and the current ambient temperature to obtain a corrected actual wall temperature, and controlling the first valve to open to a predetermined opening at least according to the required wall temperature, including: controlling the first valve to open to the predetermined opening at least according to the corrected actual wall temperature.

[0131] Optionally, the actual wall temperature is corrected according to the actual vehicle speed and the current ambient temperature of the vehicle where the methanol engine is located to obtain a corrected actual wall temperature, including: according to the actual vehicle speed, the current ambient temperature and a predetermined relationship, determining that the wall temperature correction value of the methanol engine corresponding to the actual vehicle speed and the current ambient temperature in the predetermined relationship is a target temperature, and the predetermined relationship is a correspondence between the vehicle speed, the ambient temperature and the wall temperature correction value; according to the actual wall temperature and the target temperature, determining that the corrected actual wall temperature is the difference between the actual wall temperature and the target temperature.

[0132] Optionally, the outlet of the gas channel is connected to the exhaust duct through a second valve, and the method further includes: when it is detected that the outlet temperature of the gas channel is lower than a predetermined temperature, controlling the second valve to open so that at least part of the exhaust gas in the heating chamber flows into the exhaust duct.

[0133] An embodiment of the present invention provides a methanol engine system, comprising:

[0134] A methanol engine comprises an intake duct, an exhaust duct, a first valve and a heating chamber, wherein the intake duct is used to introduce air and methanol; the exhaust duct is used to discharge exhaust gas; the heating chamber has a receiving space, the intake duct is located in the receiving space, a gas channel is formed between the intake duct and the inner wall of the heating chamber, and the inlet of the gas channel is connected to the exhaust duct through the first valve;

[0135] The controller of the methanol engine includes one or more processors, a memory and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include a control method for executing the methanol engine.

[0136] Specifically, the control method of the methanol engine includes:

[0137] Step S201, obtaining a required vaporization heat exchange amount, an actual wall temperature of the intake duct, and a flow rate to be introduced, wherein the required vaporization heat exchange amount is the heat exchange amount required for vaporization of the methanol to be introduced into the intake duct in the intake duct, and the flow rate to be introduced is the flow rate of the methanol to be introduced into the intake duct;

[0138] Specifically, the methanol to be introduced into the intake duct is the methanol to be injected into the intake duct in the next cycle. The wall surface of the intake duct is the pipe wall of the intake duct. The actual wall surface temperature is the actual temperature of the pipe wall. When the actual temperature is lower than or equal to the atomization temperature of the methanol, the methanol injected into the intake duct contacts the wall surface and atomizes.

[0139] Step S202, according to the required vaporization heat transfer amount, the flow rate to be introduced and the preset specific heat capacity of methanol, determining the heat exchange temperature difference as the ratio of the required vaporization heat transfer amount to a predetermined product, wherein the predetermined product is the product of the specific heat capacity of methanol and the flow rate to be introduced;

[0140] Specifically, the specific heat capacity of methanol is a constant at a fixed temperature. The heat exchange temperature difference is the temperature change caused by the vaporization of methanol to be injected into the intake duct in the intake duct, and the heat exchange temperature difference is determined by the heat absorption and release formula.

[0141] Step S203, determining the required wall temperature of the intake duct as the sum of the heat exchange temperature difference and the actual wall temperature, wherein the required wall temperature is the wall temperature of the intake duct required for vaporizing the methanol entering the intake duct;

[0142] Step S204, at least according to the required wall temperature, controlling the first valve to open to a predetermined opening, so that the exhaust gas in the exhaust duct enters the gas channel, and heats the wall of the intake duct so that the actual temperature of the heated wall reaches the required wall temperature.

[0143] Specifically, since the temperature of the exhaust gas discharged from the exhaust duct is generally high, the exhaust gas is passed into the heating chamber and circulated in the gas channel, so that the exhaust gas and the intake duct exchange heat, which has the effect of heating the wall of the intake duct.

[0144] Optionally, at least according to the required wall temperature, the first valve is controlled to open to a predetermined opening, including: determining the required exhaust gas flow rate according to the required wall temperature, the exhaust flow rate of the exhaust duct and the exhaust temperature of the exhaust duct; determining the predetermined opening degree according to the required exhaust gas flow rate; controlling the first valve to open to the predetermined opening degree so that the exhaust gas passes into the heating chamber at the required exhaust gas flow rate.

[0145] Optionally, obtaining the required vaporization heat exchange amount includes: obtaining the current temperature of the methanol to be introduced into the intake duct; determining the temperature rise heat exchange amount of the methanol to be introduced into the intake duct as J1=c1Q according to the specific heat capacity of the methanol, the flow rate to be introduced, the preset methanol vaporization temperature and the current temperature. me (t2-t1), J1 is the heating heat, c1 is the specific heat capacity of methanol, Q me is the flow rate to be introduced, t2 is the methanol vaporization temperature, and t1 is the current temperature; according to the flow rate to be introduced and the preset methanol vaporization heat, the vaporization heat exchange amount of the methanol to be introduced into the inlet duct is determined to be J2=Q me r, J2 is the vaporization heat exchange, r is the methanol vaporization heat; according to the heating heat exchange and the vaporization heat exchange, the required vaporization heat exchange is determined to be the sum of the heating heat exchange and the vaporization heat exchange.

[0146] Optionally, obtaining the actual temperature of the wall of the intake duct includes: obtaining the intake temperature of the intake duct, the outer diameter of the pipe of the intake duct, the wall thickness of the intake duct, the mass of the exhaust gas in the heating chamber, and the temperature difference of the exhaust gas at the inlet and outlet of the heating chamber; determining the exchange heat between the exhaust gas and the wall as J3=c2mΔt according to the exhaust gas temperature difference, the exhaust gas mass and the preset exhaust gas specific heat capacity, where J3 is the exchange heat, c2 is the exhaust gas specific heat capacity, m is the exhaust gas mass, and Δt is the exhaust gas temperature difference; determining the actual wall temperature as T=T according to the intake temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient. in +aJ3 / (Dσ), T is the actual wall temperature, T in is the intake air temperature, a is the convection heat transfer coefficient, D is the pipe outer diameter, and σ is the wall thickness.

[0147] Optionally, according to the inlet air temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient, the actual wall temperature is determined to be T=T in +aJ3 / (Dσ), before controlling the first valve to open to a predetermined opening at least according to the required wall temperature, the method further includes: correcting the actual wall temperature according to the actual vehicle speed of the vehicle where the methanol engine is located and the current ambient temperature to obtain a corrected actual wall temperature, and controlling the first valve to open to a predetermined opening at least according to the required wall temperature, including: controlling the first valve to open to the predetermined opening at least according to the corrected actual wall temperature.

[0148] Optionally, the actual wall temperature is corrected according to the actual vehicle speed and the current ambient temperature of the vehicle where the methanol engine is located to obtain a corrected actual wall temperature, including: according to the actual vehicle speed, the current ambient temperature and a predetermined relationship, determining that the wall temperature correction value of the methanol engine corresponding to the actual vehicle speed and the current ambient temperature in the predetermined relationship is a target temperature, and the predetermined relationship is a correspondence between the vehicle speed, the ambient temperature and the wall temperature correction value; according to the actual wall temperature and the target temperature, determining that the corrected actual wall temperature is the difference between the actual wall temperature and the target temperature.

[0149] Optionally, the outlet of the gas channel is connected to the exhaust duct through a second valve, and the method further includes: when it is detected that the outlet temperature of the gas channel is lower than a predetermined temperature, controlling the second valve to open so that at least part of the exhaust gas in the heating chamber flows into the exhaust duct.

[0150] An embodiment of the present invention provides a device, the device including a processor, a memory, and a program stored in the memory and executable on the processor, and when the processor executes the program, at least the following steps are implemented:

[0151] Step S201, obtaining a required vaporization heat exchange amount, an actual wall temperature of the intake duct, and a flow rate to be introduced, wherein the required vaporization heat exchange amount is the heat exchange amount required for vaporization of the methanol to be introduced into the intake duct in the intake duct, and the flow rate to be introduced is the flow rate of the methanol to be introduced into the intake duct;

[0152] Step S202, according to the required vaporization heat transfer amount, the flow rate to be introduced and the preset specific heat capacity of methanol, determining the heat exchange temperature difference as the ratio of the required vaporization heat transfer amount to a predetermined product, wherein the predetermined product is the product of the specific heat capacity of methanol and the flow rate to be introduced;

[0153] Step S203, determining the required wall temperature of the intake duct as the sum of the heat exchange temperature difference and the actual wall temperature, wherein the required wall temperature is the wall temperature of the intake duct required for vaporizing the methanol entering the intake duct;

[0154] Step S204, at least according to the required wall temperature, controlling the first valve to open to a predetermined opening, so that the exhaust gas in the exhaust duct enters the gas channel, and heats the wall of the intake duct so that the actual temperature of the heated wall reaches the required wall temperature.

[0155] The devices in this article can be servers, PCs, PADs, mobile phones, etc.

[0156] Optionally, at least according to the required wall temperature, the first valve is controlled to open to a predetermined opening, including: determining the required exhaust gas flow rate according to the required wall temperature, the exhaust flow rate of the exhaust duct and the exhaust temperature of the exhaust duct; determining the predetermined opening degree according to the required exhaust gas flow rate; controlling the first valve to open to the predetermined opening degree so that the exhaust gas passes into the heating chamber at the required exhaust gas flow rate.

[0157] Optionally, obtaining the required vaporization heat exchange amount includes: obtaining the current temperature of the methanol to be introduced into the intake duct; determining the temperature rise heat exchange amount of the methanol to be introduced into the intake duct as J1=c1Q according to the specific heat capacity of the methanol, the flow rate to be introduced, the preset methanol vaporization temperature and the current temperature. me (t2-t1), J1 is the heating heat, c1 is the specific heat capacity of methanol, Q me is the flow rate to be introduced, t2 is the methanol vaporization temperature, and t1 is the current temperature; according to the flow rate to be introduced and the preset methanol vaporization heat, the vaporization heat exchange amount of the methanol to be introduced into the inlet duct is determined to be J2=Q me r, J2 is the vaporization heat exchange, r is the methanol vaporization heat; according to the heating heat exchange and the vaporization heat exchange, the required vaporization heat exchange is determined to be the sum of the heating heat exchange and the vaporization heat exchange.

[0158] Optionally, obtaining the actual temperature of the wall of the intake duct includes: obtaining the intake temperature of the intake duct, the outer diameter of the pipe of the intake duct, the wall thickness of the intake duct, the mass of the exhaust gas in the heating chamber, and the temperature difference of the exhaust gas at the inlet and outlet of the heating chamber; determining the exchange heat between the exhaust gas and the wall as J3=c2mΔt according to the exhaust gas temperature difference, the exhaust gas mass and the preset exhaust gas specific heat capacity, where J3 is the exchange heat, c2 is the exhaust gas specific heat capacity, m is the exhaust gas mass, and Δt is the exhaust gas temperature difference; determining the actual wall temperature as T=T according to the intake temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient. in +aJ3 / (Dσ), T is the actual wall temperature, T in is the intake air temperature, a is the convection heat transfer coefficient, D is the pipe outer diameter, and σ is the wall thickness.

[0159] Optionally, according to the inlet air temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient, the actual wall temperature is determined to be T=T in+aJ3 / (Dσ), before controlling the first valve to open to a predetermined opening at least according to the required wall temperature, the method further includes: correcting the actual wall temperature according to the actual vehicle speed of the vehicle where the methanol engine is located and the current ambient temperature to obtain a corrected actual wall temperature, and controlling the first valve to open to a predetermined opening at least according to the required wall temperature, including: controlling the first valve to open to the predetermined opening at least according to the corrected actual wall temperature.

[0160] Optionally, the actual wall temperature is corrected according to the actual vehicle speed and the current ambient temperature of the vehicle where the methanol engine is located to obtain a corrected actual wall temperature, including: according to the actual vehicle speed, the current ambient temperature and a predetermined relationship, determining that the wall temperature correction value of the methanol engine corresponding to the actual vehicle speed and the current ambient temperature in the predetermined relationship is a target temperature, and the predetermined relationship is a correspondence between the vehicle speed, the ambient temperature and the wall temperature correction value; according to the actual wall temperature and the target temperature, determining that the corrected actual wall temperature is the difference between the actual wall temperature and the target temperature.

[0161] Optionally, the outlet of the gas channel is connected to the exhaust duct through a second valve, and the method further includes: when it is detected that the outlet temperature of the gas channel is lower than a predetermined temperature, controlling the second valve to open so that at least part of the exhaust gas in the heating chamber flows into the exhaust duct.

[0162] The present application also provides a computer program product, including computer instructions, which, when executed by a processor, implement at least the following method steps:

[0163] Step S201, obtaining a required vaporization heat exchange amount, an actual wall temperature of the intake duct, and a flow rate to be introduced, wherein the required vaporization heat exchange amount is the heat exchange amount required for vaporization of the methanol to be introduced into the intake duct in the intake duct, and the flow rate to be introduced is the flow rate of the methanol to be introduced into the intake duct;

[0164] Step S202, according to the required vaporization heat transfer amount, the flow rate to be introduced and the preset specific heat capacity of methanol, determining the heat exchange temperature difference as the ratio of the required vaporization heat transfer amount to a predetermined product, wherein the predetermined product is the product of the specific heat capacity of methanol and the flow rate to be introduced;

[0165] Step S203, determining the required wall temperature of the intake duct as the sum of the heat exchange temperature difference and the actual wall temperature, wherein the required wall temperature is the wall temperature of the intake duct required for vaporizing the methanol entering the intake duct;

[0166] Step S204, at least according to the required wall temperature, controlling the first valve to open to a predetermined opening, so that the exhaust gas in the exhaust duct enters the gas channel, and heats the wall of the intake duct so that the actual temperature of the heated wall reaches the required wall temperature.

[0167] Optionally, at least according to the required wall temperature, the first valve is controlled to open to a predetermined opening, including: determining the required exhaust gas flow rate according to the required wall temperature, the exhaust flow rate of the exhaust duct and the exhaust temperature of the exhaust duct; determining the predetermined opening degree according to the required exhaust gas flow rate; controlling the first valve to open to the predetermined opening degree so that the exhaust gas passes into the heating chamber at the required exhaust gas flow rate.

[0168] Optionally, obtaining the required vaporization heat exchange amount includes: obtaining the current temperature of the methanol to be introduced into the intake duct; determining the temperature rise heat exchange amount of the methanol to be introduced into the intake duct as J1=c1Q according to the specific heat capacity of the methanol, the flow rate to be introduced, the preset methanol vaporization temperature and the current temperature. me (t2-t1), J1 is the heating heat, c1 is the specific heat capacity of methanol, Q me is the flow rate to be introduced, t2 is the methanol vaporization temperature, and t1 is the current temperature; according to the flow rate to be introduced and the preset methanol vaporization heat, the vaporization heat exchange amount of the methanol to be introduced into the inlet duct is determined to be J2=Q me r, J2 is the vaporization heat exchange, r is the methanol vaporization heat; according to the heating heat exchange and the vaporization heat exchange, the required vaporization heat exchange is determined to be the sum of the heating heat exchange and the vaporization heat exchange.

[0169] Optionally, obtaining the actual temperature of the wall of the intake duct includes: obtaining the intake temperature of the intake duct, the outer diameter of the pipe of the intake duct, the wall thickness of the intake duct, the mass of the exhaust gas in the heating chamber, and the temperature difference of the exhaust gas at the inlet and outlet of the heating chamber; determining the exchange heat between the exhaust gas and the wall as J3=c2mΔt according to the exhaust gas temperature difference, the exhaust gas mass and the preset exhaust gas specific heat capacity, where J3 is the exchange heat, c2 is the exhaust gas specific heat capacity, m is the exhaust gas mass, and Δt is the exhaust gas temperature difference; determining the actual wall temperature as T=T according to the intake temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient. in +aJ3 / (Dσ), T is the actual wall temperature, T in is the intake air temperature, a is the convection heat transfer coefficient, D is the pipe outer diameter, and σ is the wall thickness.

[0170] Optionally, according to the inlet air temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient, the actual wall temperature is determined to be T=T in +aJ3 / (Dσ), before controlling the first valve to open to a predetermined opening at least according to the required wall temperature, the method further includes: correcting the actual wall temperature according to the actual vehicle speed of the vehicle where the methanol engine is located and the current ambient temperature to obtain a corrected actual wall temperature, and controlling the first valve to open to a predetermined opening at least according to the required wall temperature, including: controlling the first valve to open to the predetermined opening at least according to the corrected actual wall temperature.

[0171] Optionally, the actual wall temperature is corrected according to the actual vehicle speed and the current ambient temperature of the vehicle where the methanol engine is located to obtain a corrected actual wall temperature, including: according to the actual vehicle speed, the current ambient temperature and a predetermined relationship, determining that the wall temperature correction value of the methanol engine corresponding to the actual vehicle speed and the current ambient temperature in the predetermined relationship is a target temperature, and the predetermined relationship is a correspondence between the vehicle speed, the ambient temperature and the wall temperature correction value; according to the actual wall temperature and the target temperature, determining that the corrected actual wall temperature is the difference between the actual wall temperature and the target temperature.

[0172] Optionally, the outlet of the gas channel is connected to the exhaust duct through a second valve, and the method further includes: when it is detected that the outlet temperature of the gas channel is lower than a predetermined temperature, controlling the second valve to open so that at least part of the exhaust gas in the heating chamber flows into the exhaust duct.

[0173] Obviously, those skilled in the art should understand that the modules or steps of the present invention described above can be implemented by a general-purpose computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than herein, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0174] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0175] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0176] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0177] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0178] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0179] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0180] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0181] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0182] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for controlling a methanol engine, characterized in that: The methanol engine comprises an intake passage, an exhaust passage, a first valve and a heating chamber, wherein the intake passage is used to introduce air and methanol; the exhaust passage is used to discharge exhaust gas; the heating chamber has a receiving space, the intake passage is located in the receiving space, a gas channel is formed between the intake passage and the inner wall of the heating chamber, and the inlet of the gas channel is connected to the exhaust passage through the first valve, and the method comprises: Obtaining a required vaporization heat exchange amount, an actual wall temperature of the intake duct, and a flow rate to be introduced, wherein the required vaporization heat exchange amount is the heat exchange amount required for vaporization of the methanol to be introduced into the intake duct in the intake duct, and the flow rate to be introduced is the flow rate of the methanol to be introduced into the intake duct; According to the required vaporization heat transfer amount, the flow rate to be introduced and the preset specific heat capacity of methanol, determining the heat exchange temperature difference as the ratio of the required vaporization heat transfer amount to a predetermined product, wherein the predetermined product is the product of the specific heat capacity of methanol and the flow rate to be introduced; Determine the required wall temperature of the intake duct as the sum of the heat exchange temperature difference and the actual wall temperature, the required wall temperature being the wall temperature of the intake duct required for vaporizing the methanol entering the intake duct; At least according to the required wall temperature, the first valve is controlled to open to a predetermined opening, so that the exhaust gas in the exhaust duct enters the gas channel and heats the wall of the intake duct so that the actual temperature of the heated wall reaches the required wall temperature.

2. The method according to claim 1, characterized in that At least according to the required wall temperature, controlling the first valve to open to a predetermined opening degree comprises: determining a required exhaust gas flow rate according to the required wall temperature, the exhaust flow rate of the exhaust duct and the exhaust temperature of the exhaust duct; Determining the predetermined opening according to the exhaust gas demand flow rate; The first valve is controlled to open to the predetermined opening, so that the exhaust gas flows into the heating chamber at the required exhaust gas flow rate.

3. The method according to claim 1, characterized in that Obtain the required vaporization heat exchange amount, including: Acquiring a current temperature of the methanol to be introduced into the intake passage; According to the specific heat capacity of methanol, the flow rate to be introduced, the preset methanol vaporization temperature and the current temperature, the heating heat of the methanol to be introduced into the inlet duct is determined as J1=c1Q me (t2-t1), J1 is the heating heat, c1 is the specific heat capacity of methanol, Q me is the flow rate to be introduced, t2 is the methanol gasification temperature, and t1 is the current temperature; According to the flow rate to be introduced and the preset vaporization heat of methanol, the vaporization heat exchange amount of the methanol to be introduced into the inlet duct is determined to be J2=Q me r, J2 is the vaporization heat, r is the methanol vaporization heat; According to the heating heat exchange amount and the vaporization heat exchange amount, the required vaporization heat exchange amount is determined to be the sum of the heating heat exchange amount and the vaporization heat exchange amount.

4. The method according to claim 1, characterized in that The actual temperature of the wall surface of the air inlet duct is obtained, including: Obtaining the intake air temperature of the intake duct, the outer diameter of the intake duct, the wall thickness of the intake duct, the exhaust gas mass in the heating chamber, and the exhaust gas temperature difference between the inlet and outlet of the heating chamber; According to the exhaust gas temperature difference, the exhaust gas mass and the preset exhaust gas specific heat capacity, the exchange heat between the exhaust gas and the wall is determined to be J3=c2mΔt, where J3 is the exchange heat, c2 is the exhaust gas specific heat capacity, m is the exhaust gas mass, and Δt is the exhaust gas temperature difference; According to the inlet temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient, the actual wall temperature is determined to be T=T in +aJ3 / (Dσ), T is the actual wall temperature, T in is the intake air temperature, a is the convection heat transfer coefficient, D is the pipe outer diameter, and σ is the wall thickness.

5. The method according to claim 4, characterized in that According to the inlet air temperature, the outer diameter of the pipe, the wall thickness, the exchange heat and the preset convection heat transfer coefficient, the actual wall temperature is determined to be T=T in +aJ3 / (Dσ), before controlling the first valve to open to a predetermined opening degree at least according to the wall surface demand temperature, the method further comprises: correcting the actual wall surface temperature according to the actual vehicle speed and the current ambient temperature of the vehicle where the methanol engine is located to obtain a corrected actual wall surface temperature, Controlling the first valve to open to a predetermined opening degree at least according to the required wall temperature includes: controlling the first valve to open to the predetermined opening degree at least according to the corrected actual wall temperature.

6. The method according to claim 5, characterized in that According to the actual speed of the vehicle where the methanol engine is located and the current ambient temperature, the actual wall surface temperature is corrected to obtain the corrected actual wall surface temperature, including: According to the actual vehicle speed, the current ambient temperature and a predetermined relationship, determining a wall temperature correction value of the methanol engine corresponding to the actual vehicle speed and the current ambient temperature in the predetermined relationship as a target temperature, wherein the predetermined relationship represents a corresponding relationship between the vehicle speed, the ambient temperature and the wall temperature correction value; According to the actual wall surface temperature and the target temperature, the corrected actual wall surface temperature is determined to be the difference between the actual wall surface temperature and the target temperature.

7. The method according to claim 1, characterized in that The outlet of the gas channel is communicated with the exhaust channel through a second valve, and the method further comprises: When it is detected that the outlet temperature of the gas channel is less than a predetermined temperature, the second valve is controlled to open so that at least part of the exhaust gas in the heating chamber flows into the exhaust channel.

8. A control device for a methanol engine, characterized in that: The methanol engine comprises an intake passage, an exhaust passage, a first valve and a heating chamber, wherein the intake passage is used to introduce air and methanol; the exhaust passage is used to discharge exhaust gas; the heating chamber has a receiving space, the intake passage is located in the receiving space, a gas channel is formed between the intake passage and the inner wall of the heating chamber, the inlet of the gas channel is connected to the exhaust passage through the first valve, and the device comprises: an acquisition unit, used to acquire a required vaporization heat exchange amount, an actual wall temperature of the intake duct, and a flow rate to be introduced, wherein the required vaporization heat exchange amount is the heat exchange amount required for vaporization of the methanol to be introduced into the intake duct in the intake duct, and the flow rate to be introduced is the flow rate of the methanol to be introduced into the intake duct; A first determining unit is used to determine the heat exchange temperature difference as the ratio of the required vaporization heat exchange amount to a predetermined product according to the required vaporization heat exchange amount, the flow rate to be introduced and a preset methanol specific heat capacity, wherein the predetermined product is the product of the methanol specific heat capacity and the flow rate to be introduced; A second determining unit is used to determine the required wall temperature of the intake duct as the sum of the heat exchange temperature difference and the actual wall temperature, wherein the required wall temperature is the wall temperature of the intake duct required for vaporizing the methanol entering the intake duct; The first control unit is used to control the first valve to open to a predetermined opening degree at least according to the required wall temperature, so that the exhaust gas in the exhaust duct enters the gas channel and heats the wall of the intake duct so that the actual temperature of the heated wall reaches the required wall temperature.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the method according to any one of claims 1 to 7.

10. A methanol engine system, characterized in that: include: A methanol engine comprises an intake duct, an exhaust duct, a first valve and a heating chamber, wherein the intake duct is used to introduce air and methanol; the exhaust duct is used to discharge exhaust gas; the heating chamber has a receiving space, the intake duct is located in the receiving space, a gas channel is formed between the intake duct and the inner wall of the heating chamber, and the inlet of the gas channel is connected to the exhaust duct through the first valve; The controller of the methanol engine includes one or more processors, a memory and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include methods for executing any one of claims 1 to 7.

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