Ignition structure, engine, ignition method, and fuel supply method

Abstract

The invention provides an ignition structure, an engine, an ignition method, a fuel supply method, a computer readable storage medium, and a computer program product. The ignition structure comprises a fuel injector and an ignition device, the fuel injector is mounted on the cylinder head, the cylinder head is provided with a pre-combustion chamber and a channel, and the pre-combustion chamber can be in fluid communication with the main combustion chamber through the channel; a first injection hole and a second injection hole which are adjacent in the axial direction are distributed in the axial direction of the fuel injector. The injection direction of the first injection hole correspondingly faces the pre-combustion chamber, and a first fuel flow of first fuel can be injected to the pre-combustion chamber; and the injection direction of the second injection hole correspondingly faces the main combustion chamber, and a second fuel flow of the first fuel can be injected to the main combustion chamber.

Description

Technical Field

[0001] The present invention relates to an ignition structure, an engine, an ignition method, a fuel supply method, a computer-readable storage medium and a computer program product. Background Art

[0002] Multi-fuel engines, such as dual-fuel engines using diesel, have important application value in many scenarios, such as methanol and ammonia fuels, which are important in the low-carbon and zero-carbon strategy, and natural gas, which is already a conventional fuel, under extremely dilute conditions and with a concentration below 8%. Due to its low fuel chemical activity, it often needs to be used in combination with diesel. In addition to ignition, diesel can also control and optimize the combustion process to make the engine perform better.

[0003] Among the existing technical routes, one technical route is the diesel ignition route. Under the diesel ignition route, if the combustion system adopts the solution of direct micro-injection ignition of diesel in the cylinder, it has the disadvantages of a long ignition delay period, insufficient ignition energy and stability.

[0004] Another technical route is the pre-combustion chamber system technical route, which is to inject diesel in a relatively independent small space. The calorific value of diesel is limited by the size of the pre-combustion chamber, and the subsequent ignition combustion cannot be controlled. Therefore, the stability of the engine against external disturbances is insufficient. Therefore, the engine is limited by the leanness of the combustion and the adaptability to the chemical activity of the fuel.

[0005] In addition, on some low-speed engines with large cylinder diameters of more than 400mm, there are both pre-combustion chamber ignition injectors and in-cylinder main injectors. Therefore, high-energy ignition of small amounts of fuel can be achieved through the pre-combustion chamber injectors, and the organization and control of in-cylinder combustion can be achieved through the main injectors. However, this solution is difficult to apply to small and medium-sized engines because it requires a lot of space in the cylinder head.

[0006] Therefore, the art needs an ignition structure, an engine, an ignition method and a fuel supply method to solve at least one of the above technical problems. Summary of the invention

[0007] The object of the present invention is to provide an ignition structure.

[0008] Another object of the present invention is to provide an engine.

[0009] Another object of the present invention is to provide an ignition method.

[0010] Another object of the present invention is to provide a fuel supply method.

[0011] Another object of the present invention is to provide a computer-readable storage medium.

[0012] Another object of the present invention is to provide a computer program product.

[0013] According to one aspect of the present application, an ignition structure includes: a fuel injector; a cylinder head, wherein the fuel injector is installed on the cylinder head, and the cylinder head is provided with a pre-combustion chamber and a channel, wherein the pre-combustion chamber can be fluidically connected to a main combustion chamber through the channel; wherein, axially adjacent first injection holes and second injection holes are distributed axially in the axial direction of the fuel injector; the injection direction of the first injection hole corresponds to the pre-combustion chamber, and a first fuel flow of a first fuel can be injected into the pre-combustion chamber; the injection direction of the second injection hole corresponds to the main combustion chamber, and a second fuel flow of the first fuel can be injected into the main combustion chamber.

[0014] In one or more embodiments of the ignition structure, the first injection hole is located on a side wall of the fuel injector, and the first injection hole is fluidically connected to the pre-combustion chamber located at a side thereof.

[0015] In one or more embodiments of the ignition structure, the injection direction of the second injection hole is a first direction, the jet flame direction constructed by the injection direction of the channel and the first injection hole is a second direction, the flow direction of the vortex in the main combustion chamber is a third direction, and the component directions of the first direction and the second direction in the third direction should be consistent with the third direction.

[0016] In one or more embodiments of the ignition structure, the second injection hole is configured to inject twice in one working cycle, the first injection is a pre-injection, and the injection timing is 90°-120° before the top dead center of combustion, and the second injection is a main injection, and the injection timing is after combustion starts in the main combustion chamber.

[0017] In one or more embodiments of the ignition structure, the fuel injector also includes: a first needle valve pair matching the first injection hole, a first pilot oil circuit and a first pilot valve, and a first solenoid valve driving the first pilot valve; a second needle valve pair matching the second injection hole, a second pilot oil circuit and a second pilot valve, and a second solenoid valve driving the second pilot valve.

[0018] In one or more embodiments of the ignition structure, the first fuel and the pilot oil are independently pressurized, the pilot oil acts on one end of the needle valve, and the force direction is the needle valve closing direction, and the high-pressure first fuel acts on the other end of the needle valve, and the force direction is the needle valve opening direction.

[0019] In one or more embodiments of the ignition structure, the first pilot valve and / or the second pilot valve serves as a switch valve assembly to control the pressure of the high-pressure control chamber. After the corresponding first solenoid valve and / or the second solenoid valve is energized, the first pilot valve and / or the second pilot valve can be opened, and the pressure in the corresponding first pilot oil circuit and / or the second pilot oil circuit decreases. At this time, under the action of the high-pressure first fuel, the spring force of the corresponding first pilot oil circuit and / or the second pilot oil circuit and the needle valve spring is overcome, so that the corresponding first needle valve pair and / or the second needle valve pair is opened, so that the corresponding first injection hole and / or the second injection hole injects the first fuel flow and / or the second fuel flow.

[0020] An engine according to a second aspect of the present application comprises the ignition structure as described in the first aspect, and the engine is capable of injecting at least the first fuel and a second fuel, wherein the fuel chemical activity of the first fuel is greater than that of the second fuel.

[0021] In one or more embodiments of the engine, the first fuel is diesel fuel, and the second fuel includes methanol fuel, ammonia fuel, and low-concentration gas with a methane concentration of less than 8%.

[0022] According to a third aspect of the present application, an ignition method is used for the engine described in the second aspect, and the ignition method comprises the following steps:

[0023] receiving an input octane number signal and a concentration signal of a second fuel;

[0024] determining a feedforward first fuel flow rate according to an octane number and a fuel concentration percentage of the second fuel;

[0025] Receive a combustion cycle fluctuation (Coefficient Of Variation, COV) signal of a mean effective pressure, and if the combustion cycle fluctuation is ≤3%, execute the flow rate of the first fuel flow to be the feedforward first fuel flow rate; if COV is greater than 3% and lasts for a certain period of time, increase the flow rate of the first fuel flow according to a certain slope / single step until COV decreases to less than 3% and lasts for a certain period of time, and then reduce the flow rate of the first fuel flow again according to a certain slope / single step;

[0026] The upper limit of the flow rate of the first fuel flow does not exceed 2% of the total fuel calorific value of the second fuel flow and the second fuel injected in the working cycle, and the lower limit of the flow rate of the first fuel flow is the feedforward first fuel flow rate.

[0027] According to a fuel supply method according to a fourth aspect of the present application, for the engine according to the second aspect, the second injection hole is configured to inject twice in one working cycle, the first injection is a pre-injection, the injection time is 90°-120° before the top dead center of combustion, and the second injection is a main injection, the injection time is after the combustion starts in the main combustion chamber;

[0028] The fuel supply method comprises the following steps:

[0029] The engine speed is controlled in a closed loop, and the output parameter is the total calorific value of the fuel, including the second fuel flow injected in the working cycle and 2% of the total fuel calorific value of the second fuel;

[0030] After outputting the total calorific value of the fuel, determining the ratio of the flow rate of the second fuel stream to the second fuel;

[0031] The cylinder temperature or burst pressure signal is received, and the ratio of the injection flow rate of the main injection and the injection flow rate of the pilot injection is corrected based on the deviation between the temperature and burst pressure calibration value and the actual value under different loads.

[0032] According to a fifth aspect of the present application, a computer-readable storage medium has a computer program thereon, and the program is executed by a processor to implement the steps that can be executed by a computer in the ignition method as described in the third aspect, and / or the fuel supply method as described in the fourth aspect.

[0033] A computer program product according to the sixth aspect of the present application includes a computer program, which, when executed by a processor, implements the steps that can be executed by a computer in the ignition method described in the third aspect and / or the fuel supply method described in the fourth aspect.

[0034] The beneficial effects of the above embodiments include, but are not limited to, the ignition structure is matched with the pre-combustion chamber structure on the cylinder head through an integrated multi-spray hole fuel injector, and a single fuel injector can be used to achieve both pre-combustion chamber ignition and diesel injection in the main combustion chamber to achieve deeper combustion control. In addition, based on the ignition structure, an ignition method and a fuel supply method can be further provided that can simultaneously take into account rapid and stable ignition and deep control of the subsequent combustion heat release process. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments. In the accompanying drawings, the same reference numerals always represent the same features. It should be noted that these drawings are only examples and are not drawn according to the conditions of equal scale, and should not be used as a limitation on the actual scope of protection required by the present invention, wherein:

[0036] Figure 1 , Figure 2 FIG. 1 is a schematic diagram of an ignition structure according to an embodiment of the present invention.

[0037] Figure 3 The figure is a schematic structural diagram of a fuel injector of an ignition structure according to an embodiment.

[0038] Figure 4 The figure is a flow chart of an ignition method according to an embodiment.

[0039] Figure 5 FIG. 4 is a flow chart of an ignition method according to another embodiment.

[0040] Figure 6 The figure is a flow chart of a fuel supply method according to an embodiment.

[0041] Figure 7 as well as Figure 8 FIG. 4 is a flow chart of a fuel supply method according to another embodiment. DETAILED DESCRIPTION

[0042] Reference will now be made in detail to various embodiments of the present invention, examples of which are shown in the accompanying drawings and described below. Although the present invention will be described in conjunction with the exemplary embodiments, it should be appreciated that this specification is not intended to limit the present invention to those exemplary embodiments. On the contrary, the present invention is intended to cover not only these exemplary embodiments, but also various alternative forms, modifications, equivalent forms and other embodiments that may be included within the spirit and scope of the present invention as defined by the appended claims.

[0043] In the following description, the orientation or positional relationship indicated by "inside", "outside", "upper", "lower", "top", "bottom" or other orientation terms is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0044] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "some embodiments" means a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "some embodiments" mentioned twice or multiple times in different locations in this specification do not necessarily refer to the same embodiment. In addition, some features, structures or characteristics of some embodiments of the present application can be appropriately combined.

[0045] The present application provides an engine, including an ignition structure to be described in detail in the following embodiments, the engine can at least inject a first fuel and a second fuel, the fuel chemical activity of the first fuel being greater than that of the second fuel. Specifically, as described above, the first fuel can be diesel fuel as an example, and the second fuel can include methanol fuel, ammonia fuel, and low-concentration gas with a methane concentration of less than 8% as an example. In the following description, the first fuel is referred to as diesel.

[0046] refer to Figures 1 to 3 As shown, the ignition structure includes a fuel injector 1 and a pre-combustion chamber 2. The pre-combustion chamber 2 is designed to be embedded in the cylinder head 5, and the cylinder head 5 and the fuel injector 1 are positioned and sealed by a sealing surface 4, and the pre-combustion chamber 2 and the main combustion chamber 200 are connected through a channel 12. The fuel injector 1 is installed on the cylinder head 2.

[0047] The meaning of the main combustion chamber 200 is similar to that of the "combustion chamber" in the art, that is, the space defined by the cylinder head, the cylinder and the top of the piston.

[0048] Axially adjacent first injection holes 110 and second injection holes 111 are distributed in the axial direction of the fuel injector 1 .

[0049] The first injection hole 110 is disposed in an injection direction corresponding to the pre-combustion chamber 2 , and can inject a first fuel flow of the first fuel into the pre-combustion chamber 2 .

[0050] In some embodiments, a specific structure may be that the first injection hole 110 is located on a side wall of the fuel injector 1 , and the first injection hole 110 is fluidically connected to the pre-combustion chamber 2 located on the side thereof.

[0051] The second injection hole 111 is disposed in an injection direction corresponding to the main combustion chamber 200, and can inject a second fuel flow of the first fuel into the main combustion chamber.

[0052] The first fuel flow is generally used for pilot combustion, and the second fuel flow is generally injected into the main combustion chamber 200 , so the first fuel flow here is the pilot diesel 11 , and the second fuel flow here is the main injection fuel 13 .

[0053] During operation, the fuel injector can inject the main fuel 13 and the pilot diesel 11, and the injection start point and injection pulse width control of the two are independent of each other.

[0054] After the pilot diesel 11 ignites in the pre-combustion chamber 2, the flame enters the main combustion chamber 200 from the channel 12 to generate a jet flame 14. The jet flame 14 has strong ignition energy, which is beneficial to the ignition and combustion of the premixed low-activity, low-concentration mixture in the main combustion chamber 200.

[0055] The directions of the jet flame 14 and the main diesel injection 13 should take into account the direction of the large-scale vortex 3 in the cylinder, so that the two directions are consistent, and the flame development speed in the cylinder is promoted to the greatest extent. That is, the injection direction of the second injection hole 111 is the first direction, the direction of the jet flame 14 constructed by the injection direction of the channel 12 and the first injection hole 110 is the second direction, and the flow direction of the vortex 3 in the main combustion chamber is the third direction, and the direction of the components of the first direction and the second direction in the third direction should be consistent with the third direction. For example, if the flow direction of the vortex 3 is counterclockwise, the components of the first direction and the second direction in the circumferential direction are also counterclockwise, rather than the opposite clockwise.

[0056] In some embodiments, the second injection hole 111 is configured to inject twice in one working cycle. The first injection is a pre-injection, and the injection time is 90°-120° before the top dead center of combustion, which enriches the low-concentration / low-activity mixture in the cylinder to a certain extent and improves the activity; the second injection is a main injection, and the injection time is after the combustion starts in the main combustion chamber. The high-speed diesel spray can promote combustion to a certain extent. The interval and injection amount ratio between the two can reasonably control the combustion process.

[0057] Continue to refer Figures 1 to 3 As shown, the integrated multi-dimensional injector structure adopts a dual solenoid valve combined with a high-pressure common rail fuel supply architecture, and the fuel injector 1 further includes: a first needle valve pair 107 matching the first injection hole 110, a first pilot oil circuit 109 and a first pilot valve 101, and a first solenoid valve 102 driving the first pilot valve 101; a second needle valve pair 106 matching the second injection hole 111, a second pilot oil circuit 105 and a second pilot valve 104, and a second solenoid valve 103 driving the second pilot valve 104. In some embodiments, the pilot valve can be a ball valve, but is not limited thereto.

[0058] During the operation of the injector 1, the diesel and pilot oil build up pressure independently to prepare for injection. Specifically, the pilot oil pressure acts on the top of the needle valve, and the force direction is the needle valve closing direction (downward); the high-pressure diesel acts on the bottom of the needle valve, and the force direction is the needle valve opening direction (upward).

[0059] During operation, the first pilot valve 101 and the second pilot valve 104 act as switch valve components to control the pressure of the high-pressure control chamber. After the corresponding first solenoid valve 102 and the second solenoid valve 103 are energized, the first pilot valve 101 and the second pilot valve 104 can be opened, and the corresponding cavity pressures of the first pilot oil circuit 109 and the second pilot oil circuit 105 decrease. At this time, under the action of high-pressure diesel, the spring force of the corresponding first pilot oil circuit 109 and the second pilot oil circuit 105 and the needle valve spring 108 are overcome, so that the corresponding first needle valve pair 107 and the second needle valve pair 106 are opened, and the high-pressure diesel starts to spray, so that the corresponding first injection hole and the second injection hole spray the first fuel flow and the second fuel flow.

[0060] On the contrary, when the first pilot valve 101 and the second pilot valve 104 are closed, the first pilot oil circuit 109 and the second pilot oil circuit 105 accumulate pressure again, and the pressure increases. At this time, the control chamber pressure is greater than the high-pressure diesel pressure, and under the joint action of the downward spring force of the needle valve spring 108, the corresponding first needle valve pair 107 and the second needle valve pair 106 are closed.

[0061] It can be understood that it should be noted that the basic principles of the main fuel injection 13 and the pilot diesel injection 11 are similar, so they are described uniformly. In the actual working process, the two are independently controlled in time and space dimensions without interfering with each other.

[0062] refer to Figure 4 as well as Figure 5 As shown, the present application also provides an ignition method, which is used for the engine introduced in the above embodiment, and the ignition method comprises the following steps:

[0063] S2001. Receive an input signal of an octane number and a concentration of a second fuel;

[0064] S2002. Determine the feedforward first fuel flow rate according to the octane number and fuel concentration percentage of the second fuel;

[0065] S2003. Receive a combustion cycle fluctuation (Coefficient Of Variation, COV) signal of a mean effective pressure, and if the combustion cycle fluctuation is ≤3%, execute the flow rate of the first fuel flow to be the feedforward first fuel flow rate; if COV is greater than 3% and lasts for a certain period of time, increase the flow rate of the first fuel flow according to a certain slope / single step until COV decreases to less than 3% and lasts for a certain period of time, and then reduce the flow rate of the first fuel flow again according to a certain slope / single step;

[0066] The upper limit of the flow rate of the first fuel flow does not exceed 2% of the total fuel calorific value of the second fuel flow and the second fuel injected in the working cycle, and the lower limit of the flow rate of the first fuel flow is the feedforward first fuel flow rate.

[0067] refer to Figure 5 As shown, in some embodiments, the specific steps of the ignition method may include:

[0068] S201: Determine the basic pilot oil quantity q1 according to the speed-power table;

[0069] S202: Read engine cycle fluctuation rate CoV imep Value, for CoV imep Whether it exceeds the limit is determined, if CoV imep ≤3% and lasts for 2s, proceed to step 203, otherwise proceed to step 206;

[0070] S203: Select single-step correction or step correction to perform calibration. If single-step correction is selected,

[0071] Go to step 204; if step correction is selected, go to step 205;

[0072] S204: Restore the amount of pilot oil to q1 at one time.

[0073] S205: According to a certain correction amount Δq (which can be calibrated), the amount of pilot oil is gradually reduced to q1.

[0074] S206: Select single-step correction or step correction to perform calibration. If step correction is selected,

[0075] Go to step 207; if single-step correction is selected, go to step 208;

[0076] S207: Step correction of ignition oil quantity q1+Δq, the correction quantity Δq can be calibrated; maximum correction is configured

[0077] Positive limit q 1max , can be calibrated;

[0078] S208: One-time correction of ignition oil quantity, with maximum correction limit q 1max , can be calibrated.

[0079] refer to Figure 6 As shown, in some embodiments, the present application also provides a fuel supply method for the engine introduced in the above embodiment, wherein the second injection hole is configured to inject twice in one working cycle, the first injection is a pre-injection, and the injection time is 90°-120° before the top dead center of combustion, and the second injection is a main injection, and the injection time is after the combustion starts in the main combustion chamber.

[0080] The fuel supply method may include the following steps:

[0081] S3001. Closed-loop control of the engine speed, the output parameter is the total calorific value of the fuel, including 2% of the total fuel calorific value of the second fuel flow and the second fuel injected in the working cycle;

[0082] S3002. After outputting the total calorific value of the fuel, determine the ratio of the flow rate of the second fuel flow to the second fuel;

[0083] S3003. Receive the in-cylinder temperature or explosion pressure signal, and correct the ratio of the injection flow rate of the main injection and the injection flow rate of the pre-injection based on the deviation between the temperature and explosion pressure calibration value and the actual value under different loads.

[0084] refer to Figure 7 as well as Figure 8 As shown, in some embodiments, the fuel supply method may include the following steps:

[0085] S301: Calculate the speed difference according to the target speed and the actual speed.

[0086] S302: Look up the table according to the actual power and speed to obtain the proportional, integral and differential correction coefficients in static and dynamic conditions.

[0087] S303: Based on the speed difference obtained in step 301 and the static / dynamic PID obtained in step 302

[0088] Correction coefficient, and compare with PID limit range, calculate the final PID output result, and get the basic total fuel quantity Q. The total fuel quantity Q includes: pre-injection quantity Q1, main injection quantity Q2 and converted premixed fuel quantity Q3, excluding pilot fuel quantity q.

[0089] S304: Determine the maximum oil quantity limit Q according to the speed and running time max and minimum oil quantity limit

[0090] Q min , compare Q and Q max Take the minimum value and assign Q; compare Q min And Q, take the maximum value and assign Q.

[0092] S305: Comparison of Q and external characteristic oil quantity Q EC , take the minimum value, assign Q, and get the final total oil volume Q.

[0094] S306: Determine the fuel ratio 1 coefficient, α and β values ​​by looking up the table according to the engine speed and power. Calculate the total fuel volume Q' according to the total fuel volume Q and the formula Q'=α*Q, where

[0095] Q'=Q1+Q2; calculate the converted premixed fuel oil quantity Q3 according to the total oil quantity Q and the formula Q3=β*Q.

[0096] Output Q3 is given to the premixed fuel quantity controller.

[0097] S307: Calculate the difference between the set cylinder temperature (or explosion pressure) and the actual cylinder temperature (or explosion pressure).

[0098] S308: Look up the table according to the actual power and speed to obtain the proportional, integral and differential correction coefficients in static and dynamic conditions. And calculate the PID sum according to the difference obtained in step 307, and output the PID correction term ΔΥ of proportion 2.

[0099] S309: Determine the feedforward value Y0 of ratio 2 according to the rotation speed and power.

[0100] S310: Assign Y=Y0+ΔY. Calculate the pre-injection amount according to the ratio Y and the formula Q1=Q'*Y; calculate the main injection amount according to the ratio Y and the formula Q2=Q'*(1-Y). Output Q1 and Q2 to the fuel injection controller.

[0101] S311: Determine the crankshaft angle θ1 corresponding to the start point of the pilot injection according to the rotation speed and power, determine the crankshaft angle θ2 corresponding to the start point of the main injection according to the rotation speed and power, and output θ1 and θ2 to the fuel injection controller.

[0102] Another aspect of the present application further provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the steps that can be executed by a computer in the ignition method and / or the fuel supply method described in the above embodiments. Please refer to the above description for details, which will not be repeated here.

[0103] In addition, it is understandable that the above-mentioned computer-readable storage medium may also be in a system form, that is, including multiple computer-readable storage sub-media to jointly implement the steps of the ignition method and / or fuel supply method described above through multiple computer-readable storage media.

[0104] In addition, another aspect of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the ignition method and / or fuel supply method described in the above embodiments that can be executed by a computer. Please refer to the above description for details, which will not be repeated here.

[0105] In summary, the beneficial effects of the ignition structure, engine, ignition method, fuel supply method, computer-readable storage medium, and computer program product described above include, but are not limited to, the ignition structure matches the pre-combustion chamber structure on the cylinder head through an integrated multi-hole fuel injector, and a single fuel injector can be used to achieve both pre-combustion chamber ignition and deeper combustion control by injecting diesel in the main combustion chamber. In addition, based on the ignition structure, an ignition method and a fuel supply method can be further provided that can simultaneously take into account rapid and stable ignition and deep control of the subsequent combustion heat release process.

[0106] The various illustrative logic modules and circuits described in conjunction with the embodiments disclosed herein may be implemented or executed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in cooperation with a DSP core, or any other such configuration.

[0107] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. The software module may reside in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor so that the processor can read and write information from / to the storage medium. In an alternative, a storage medium may be integrated into a processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In an alternative, the processor and the storage medium may reside in a user terminal as discrete components.

[0108] In one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented as a computer program product in software, each function may be stored on or transmitted by a computer-readable medium as one or more instructions or codes. Computer-readable media include both computer storage media and communication media, including any media that facilitates the transfer of a computer program from one place to another. Storage media may be any available media that can be accessed by a computer. As an example and not limitation, such a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of an instruction or data structure and can be accessed by a computer. Any connection is also properly referred to as a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwaves, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwaves are included in the definition of the medium. Disk and disc as used herein include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, wherein disk often reproduces data magnetically, while disc reproduces data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0109] Although the present invention is disclosed as above in terms of preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection defined by the claims of the present invention.

Claims

1. An ignition structure, characterized in that: include: Fuel injectors; a cylinder head, the fuel injector being mounted on the cylinder head, the cylinder head being provided with a pre-combustion chamber, and a passage through which the pre-combustion chamber can be fluidically communicated with a main combustion chamber; Wherein, a first injection hole and a second injection hole adjacent to each other in the axial direction of the fuel injector are distributed in the axial direction; The first injection hole is disposed in an injection direction corresponding to the pre-combustion chamber, and is capable of injecting a first fuel flow of a first fuel into the pre-combustion chamber; The second injection hole is disposed in an injection direction corresponding to the main combustion chamber, and can inject a second fuel flow of the first fuel into the main combustion chamber.

2. The ignition structure according to claim 1, characterized in that: The first injection hole is located at a side wall of the fuel injector, and the first injection hole is fluidly connected with the pre-combustion chamber located at a side thereof.

3. The ignition structure according to claim 1, characterized in that: The injection direction of the second injection hole is a first direction, the jet flame direction constructed by the injection direction of the channel and the first injection hole is a second direction, the flow direction of the vortex in the main combustion chamber is a third direction, and the component directions of the first direction and the second direction in the third direction should be consistent with the third direction.

4. The ignition structure according to claim 1, characterized in that: The second injection hole is configured to inject twice in one working cycle, the first injection is a pre-injection, the injection time is 90°-120° before the top dead center of combustion, and the second injection is a main injection, the injection time is after the combustion starts in the main combustion chamber.

5. The ignition structure according to claim 1, characterized in that: The fuel injector further comprises: A first needle valve pair matching the first injection hole, a first pilot oil circuit and a first pilot valve, and a first solenoid valve driving the first pilot valve; A second needle valve pair matching the second injection hole, a second pilot oil circuit and a second pilot valve, and a second solenoid valve driving the second pilot valve.

6. The ignition structure according to claim 5, characterized in that: The first fuel and the pilot oil build up pressure independently. The pilot oil acts on one end of the needle valve with the force direction being the needle valve closing direction. The high-pressure first fuel acts on the other end of the needle valve with the force direction being the needle valve opening direction.

7. The ignition structure according to claim 5, characterized in that: The first pilot valve and / or the second pilot valve serve as a switch valve assembly to control the pressure in the high-pressure control chamber. After the corresponding first solenoid valve and / or the second solenoid valve is energized, the first pilot valve and / or the second pilot valve can be opened, and the pressure in the corresponding first pilot oil circuit and / or the second pilot oil circuit decreases. At this time, under the action of the high-pressure first fuel, the spring force of the corresponding first pilot oil circuit and / or the second pilot oil circuit and the needle valve spring is overcome, so that the corresponding first needle valve pair and / or the second needle valve pair is opened, so that the corresponding first injection hole and / or the second injection hole injects the first fuel flow and / or the second fuel flow.

8. An engine, characterized in that: The engine comprises the ignition structure as claimed in any one of claims 1 to 7, and is capable of injecting at least the first fuel and a second fuel, wherein the fuel chemical activity of the first fuel is greater than that of the second fuel.

9. The engine according to claim 8, characterized in that The first fuel is diesel fuel, and the second fuel includes methanol fuel, ammonia fuel, and low-concentration gas with a methane concentration of less than 8%.

10. An ignition method, characterized in that: For the engine according to claim 8 or 9, the ignition method comprises the following steps: receiving an input octane number signal and a concentration signal of a second fuel; determining a feedforward first fuel flow rate according to an octane number and a fuel concentration percentage of the second fuel; Receive a combustion cycle fluctuation (Coefficient Of Variation, COV) signal of a mean effective pressure, and if the combustion cycle fluctuation is ≤3%, execute the flow rate of the first fuel flow to be the feedforward first fuel flow rate; if COV is greater than 3% and lasts for a certain period of time, increase the flow rate of the first fuel flow according to a certain slope / single step until COV decreases to less than 3% and lasts for a certain period of time, and then reduce the flow rate of the first fuel flow again according to a certain slope / single step; The upper limit of the flow rate of the first fuel flow does not exceed 2% of the total fuel calorific value of the second fuel flow and the second fuel injected in the working cycle, and the lower limit of the flow rate of the first fuel flow is the feedforward first fuel flow rate.

11. A fuel supply method, characterized in that: For the engine of claim 8 or 9, the second injection hole is configured to inject twice in one working cycle, the first injection is a pre-injection, the injection time is 90°-120° before the top dead center of combustion, and the second injection is a main injection, the injection time is after the combustion starts in the main combustion chamber; The fuel supply method comprises the following steps: The engine speed is controlled in a closed loop, and the output parameter is the total calorific value of the fuel, including the second fuel flow injected in the working cycle and 2% of the total fuel calorific value of the second fuel; After outputting the total calorific value of the fuel, determining the ratio of the flow rate of the second fuel stream to the second fuel; The cylinder temperature or burst pressure signal is received, and the ratio of the injection flow rate of the main injection and the injection flow rate of the pilot injection is corrected based on the deviation between the temperature and burst pressure calibration value and the actual value under different loads.

12. A computer-readable storage medium having a computer program thereon, characterized in that: The program is executed by a processor to implement the steps of the ignition method according to claim 10 and / or the fuel supply method according to claim 11 that can be executed by a computer.

13. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the computer program implements the steps that can be executed by a computer in the ignition method according to claim 10 and / or the fuel supply method according to claim 11.

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