Method, device and system for determining structural parameters of combustion system

Abstract

The present application provides a method, device and system for determining the structural parameters of a combustion system. The combustion system includes a combustion chamber, an injector and a piston, and the combustion chamber includes a plurality of fan-shaped sub-areas, including: setting the initial value of the angle and the initial value of the radius of each fan-shaped sub-area, and calculating the air utilization rate of each fan-shaped sub-area according to the initial value; when the air utilization rate is less than a preset threshold, reducing the value of the angle and the value of the radius until the air utilization rate of the fan-shaped sub-area after the reduction is greater than or equal to the preset threshold, determining the current value of the angle as the final angle, and determining the current value of the radius as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system. Through the present application, the problem that the structure of the combustion chamber in the prior art cannot fully burn the fuel is solved.

Description

Technical Field

[0001] The present application relates to the technical field of structural design of combustion systems, and in particular, to a method, device, computer-readable storage medium and system for determining structural parameters of a combustion system. Background Art

[0002] At present, with the development of technology, higher requirements are put forward for the fuel consumption and emissions of diesel engines. The explosion pressure and compression ratio of the engine are constantly increasing. While improving the economy, it will also lead to worsening emissions. Therefore, how to design the combustion system has become a difficult problem in the industry. Because with the increase of compression ratio, the space utilization rate in the cylinder is reduced. How to reasonably match the injector and the combustion chamber to improve the air utilization rate in the combustion chamber and the uniformity of the distribution of the combustible mixture, and speed up the combustion speed is a common problem in the design of the combustion system of the current traditional internal combustion engine.

[0003] The combustion process of a diesel engine is a typical premixed-diffusion combustion mode dominated by diffusion combustion. Diesel fuel burns while it is sprayed, and the injection speed determines the combustion speed. The existing injector technology simply divides the spray holes into two layers, with the same diameter of the upper and lower rows, and matches the existing step-type combustion chamber structure, which limits the oil-gas mixing and is not conducive to the rapid mixing of oil and gas in the cylinder. If the number of holes in a traditional injector is increased, it will lead to structural and processing limitations, and direct stratification will lead to uneven oil-gas mixing. Therefore, in the existing single-row hole injector solution, due to the limitations of the injector structure, the number of spray holes cannot be further increased. At the same time, considering the limitation of smoke density, the space for increasing the flow rate will also be limited. At the same time, for the step-type combustion chamber, different from the traditional single-row hole technology, the double-row hole injector has different oil beam landing points and different profile designs, which require further targeted design. Summary of the invention

[0004] The main purpose of the present application is to provide a method, device, computer-readable storage medium and system for determining structural parameters of a combustion system, so as to at least solve the problem in the prior art that the structure of the combustion chamber cannot fully burn the fuel.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a method for determining the structural parameters of a combustion system is provided, the combustion system comprising a combustion chamber, an injector and a piston, the combustion chamber comprising a plurality of fan-shaped sub-areas, comprising: setting an initial value of the angle and an initial value of the radius of each fan-shaped sub-area, and determining the air utilization rate of each fan-shaped sub-area according to the initial values; when the air utilization rate is less than a preset threshold, reducing the values ​​of the angle and the radius until the air utilization rate of the fan-shaped sub-area after reduction is greater than or equal to the preset threshold, determining the current value of the angle as the final angle, and determining the current value of the radius as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system.

[0006] Optionally, when the air utilization rate is less than a preset threshold, the value of the angle and the value of the radius are reduced until the air utilization rate of the fan-shaped sub-area after the reduction is greater than or equal to the preset threshold, comprising: a determination step: when the air utilization rate is less than the preset threshold, the value of the angle and the value of the radius are reduced to determine the air utilization rate of the fan-shaped sub-area after the reduction; the determination step is performed at least once until the air utilization rate is greater than or equal to the preset threshold, to obtain the current value of the angle and the current value of the radius.

[0007] Optionally, the air utilization rate of each of the sector-shaped sub-regions is determined according to the initial value, including: simulating each of the sector-shaped sub-regions under the initial value conditions; obtaining a mapping relationship between the engine crankshaft angle and the excess air coefficient in each simulated sector-shaped sub-region, and determining the air utilization rate according to the mapping relationship.

[0008] Optionally, after obtaining the final angle and final radius of the fan-shaped sub-region, the method further includes: calculating the volume of the fan-shaped sub-region, and calculating the volume ratio of the fan-shaped sub-region based on the volume; determining the injection amount ratio of the fan-shaped sub-region based on the volume ratio, and determining the nozzle aperture of the injector based on the injection amount ratio, wherein the nozzle aperture is the final structural design parameter.

[0009] Optionally, the volumetric proportion of the sector-shaped sub-area is calculated based on the volume, including: obtaining the total volume of the combustion chamber, calculating the ratio of the volume of the sector-shaped sub-area to the total volume, and obtaining the volumetric proportion; determining the fuel injection amount proportion of the sector-shaped sub-area based on the volumetric proportion, including: obtaining the total fuel injection amount, calculating the product of the volumetric proportion and the total fuel injection amount, and obtaining the fuel injection amount proportion.

[0010] Optionally, determining the nozzle aperture of the injector according to the fuel injection amount ratio includes: according to the formula Calculate the aperture cross-sectional area of ​​the injector, wherein A is the aperture cross-sectional area, n is the engine speed where the plurality of sector sub-regions are located, m is the injection amount of each sector sub-region, μ is the flow coefficient of the aperture of the injector, v represents the injection speed of the injector, and t represents the injection duration; according to the formula The nozzle aperture of the fuel injector is calculated, wherein i represents the number of the fuel injectors and d represents the nozzle aperture.

[0011] Optionally, setting the initial value of the angle and the initial value of the radius of each of the fan-shaped sub-regions includes: setting the initial value of the angle of any two of the fan-shaped sub-regions to be the same; setting the initial value of the radius of any two of the fan-shaped sub-regions to be the same.

[0012] According to another aspect of the present application, a device for determining the structural parameters of a combustion system is provided, the combustion system comprising a combustion chamber, an injector and a piston, the combustion chamber comprising a plurality of fan-shaped sub-areas, comprising: a first determination unit, for setting an initial value of an angle and an initial value of a radius of each of the fan-shaped sub-areas, and determining the air utilization rate of each of the fan-shaped sub-areas according to the initial values; a second determination unit, for reducing the values ​​of the angle and the radius when the air utilization rate is less than a preset threshold value, until the air utilization rate of the fan-shaped sub-area after reduction is greater than or equal to the preset threshold value, determining the current value of the angle as the final angle, and determining the current value of the radius as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system.

[0013] 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 run, the device where the computer-readable storage medium is located is controlled to execute any one of the methods for determining the structural parameters of the combustion system.

[0014] According to another aspect of the present application, a system for determining the structural parameters of a combustion system is provided, comprising: a combustion system comprising a combustion chamber, an injector and a piston, wherein the combustion chamber comprises a plurality of sector-shaped sub-regions; a controller 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 a method for determining the structural parameters of the combustion system for executing any one of the above-described methods.

[0015] Applying the technical solution of the present application, the initial value of the angle and the initial value of the radius of each sector-shaped sub-area are set, and the air utilization rate of each sector-shaped sub-area is calculated based on the initial value; when the air utilization rate is less than the preset threshold, the value of the angle and the value of the radius are reduced until the air utilization rate of the sector-shaped sub-area after the reduction is greater than or equal to the preset threshold, and the current value of the angle is determined as the final angle, and the current value of the radius is determined as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system. Compared with the prior art, in which the structure of the combustion chamber is not convenient for the full combustion of the fuel, the present application adjusts the structural parameters of the combustion system by setting the initial value and calculating the air utilization rate under the initial value condition, so that the adjusted structure of the combustion chamber is more conducive to the full combustion of the fuel. Therefore, it can solve the problem in the prior art that the structure of the combustion chamber is not convenient for the full combustion of the fuel, and achieve the effect of reasonably designing the structural parameters of the combustion chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] 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:

[0017] Figure 1 A hardware structure block diagram of a mobile terminal for executing a method for determining structural parameters of a combustion system provided in an embodiment of the present application is shown;

[0018] Figure 2 A schematic flow chart of a method for determining structural parameters of a combustion system provided in an embodiment of the present application is shown;

[0019] Figure 3 A schematic structural diagram of a combustion chamber provided in an embodiment of the present application is shown;

[0020] Figure 4 A schematic diagram of the nozzle structure distribution of a fuel injector provided in an embodiment of the present application is shown;

[0021] Figure 5 A schematic diagram of the arrangement angle of the spray holes of a fuel injector provided in an embodiment of the present application is shown;

[0022] Figure 6 A schematic diagram of a pit depth structure of a combustion chamber provided in an embodiment of the present application is shown;

[0023] Figure 7 A schematic diagram showing the air utilization rate of each sector sub-area under a simulation situation provided by an embodiment of the present application is shown;

[0024] Figure 8A schematic flow chart of a method for determining structural parameters of a specific combustion system provided in an embodiment of the present application is shown;

[0025] Fig. 9 A structural block diagram of a device for determining structural parameters of a combustion system provided in an embodiment of the present application is shown.

[0026] The above drawings include the following reference numerals:

[0027] 102, processor; 104, memory; 106, transmission device; 108, input and output devices. DETAILED DESCRIPTION

[0028] 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.

[0029] 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.

[0030] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned 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.

[0031] For the convenience of description, some nouns or terms involved in the embodiments of the present application are explained below:

[0032] Compression ratio: It indicates the degree of compression of the gas. The ratio of the total volume of the cylinder to the volume of the combustion chamber is called the compression ratio.

[0033] As introduced in the background technology, in the existing single-row hole injector solution in the prior art, due to the structural limitation of the injector, the number of spray holes cannot be further increased. At the same time, considering the limitation of smoke density, the space for increasing the flow rate will also be limited, which is not conducive to the full combustion of the fuel. In order to solve the problem that the structure of the combustion chamber is not conducive to the full combustion of the fuel, the embodiments of the present application provide a method, device, computer-readable storage medium and system for determining the structural parameters of a combustion system.

[0034] 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.

[0035] 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 determining structural parameters of a combustion system 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 only for illustration and does not limit the structure of the mobile terminal. Figure 1 More or fewer components as shown, or with Figure 1 Different configurations shown.

[0036] 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 method for determining the structural parameters of the combustion system 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 above method 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 can be connected to the mobile terminal via a network. Examples of the above 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 above 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.

[0037] In this embodiment, a method for determining the structural parameters of a combustion system 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.

[0038] Figure 2 FIG. 1 is a flow chart of a method for determining structural parameters of a combustion system according to an embodiment of the present application. Figure 2 As shown, the combustion system includes a combustion chamber, a fuel injector and a piston, wherein the combustion chamber includes a plurality of sector-shaped sub-areas, and the method includes the following steps:

[0039] Step S201, setting an initial value of the angle and the initial value of the radius of each of the fan-shaped sub-areas, and determining the air utilization rate of each of the fan-shaped sub-areas according to the initial values;

[0040] Specifically, the structural diagram of the combustion chamber is as follows: Figure 3As shown, the combustion chamber is divided into multiple sector-shaped sub-areas with the center of the piston in the combustion chamber system as the center of the circle and the radius from the inner wall of the combustion chamber to the center of the piston as V1 and V2. Each sector-shaped sub-area corresponds to an injector, and the injector sprays fuel to the corresponding sector-shaped sub-area. The piston is generally located in the middle of the combustion chamber. The injector is a double-row hole injector nozzle arrangement. The injector nozzle is divided into two rows, upper and lower, and the number of holes is not less than 10. The number of holes in this scheme is 16, 8 in the upper and lower rows, as shown in FIG. Figure 4 The angle between the oil beams in the upper row of holes is α, and the angle between the lower row is β. The angle between the upper and lower rows of nozzles can be arranged evenly or unevenly, and they are staggered, such as Figure 5 As shown. For the 16-hole uniformly distributed spray hole injector, its α and β are 45° respectively. For the asymmetric specific angle matching, it needs to be determined by calculation based on the combustion chamber profile. The aperture and oil volume distribution of the double-row holes need to be determined through simulation. According to the different oil beam landing areas, the combustion chamber is divided into 16 corresponding sector-shaped sub-areas. Each area corresponds to a spray hole that sprays fuel into the area. A raised arc ridge is set between adjacent areas. The raised arc ridge design consists of two adjacent protrusions and the piston surface. The volume of the sector-shaped area to the center of the piston is v1, and other similar spaces are v2 to v n As mentioned above Figure 3 As shown. The volume of the entire combustion chamber is V, and the volume ratio of each space is v / V. The angle γ between the convex arc ridges of the asymmetric structure (that is, the angle of the fan-shaped sub-areas formed) is different, ranging from 15° to 45°, which is used to form different regional volumes. Targeted, and the pit depth H of each area (that is, the radius of the fan-shaped sub-area) is also different, generally ranging from H = (0.11~0.2) D, D can be the diameter of the cylinder, such as Figure 6 As shown, H1 and H2 represent the radius of two different fan-shaped sub-areas. For the combustion chamber profile of the symmetrical structure, the initial γ and pit depth H of each area of ​​the combustion chamber are the same value, so the volume of each area is the same, and the apertures of the injectors are also the same. In order to further improve the air utilization rate, this scheme designs the combustion chamber into an asymmetric structure, and the apertures of the injectors are different, so the corresponding fuel injection amount in each space is also different.

[0041] Step S202, when the air utilization rate is less than a preset threshold, reduce the value of the angle and the value of the radius until the air utilization rate of the fan-shaped sub-area after reduction is greater than or equal to the preset threshold, determine the current value of the angle as the final angle, and determine the current value of the radius as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system.

[0042] Specifically, simulation is performed for each sector sub-area, the actual volume of the sector sub-area is simulated, the fuel injection amount under real conditions is simulated, and the air utilization rate is calculated. When the air utilization rate is less than the preset threshold, that is, the oil-gas mixing effect is not good, the value of the angle and the value of the radius are adjusted. Generally, the lower the air utilization rate, the smaller the value of the angle and the value of the radius of the corresponding sector sub-area need to be adjusted. The basis for adjustment is the comparison of air utilization rates in different spaces. The goal is to approach the optimal result. Usually H is adjusted to about 0.15D. The range of γ is within ±10°. Until the air utilization rate of the sector sub-area after reduction is greater than or equal to the preset threshold, it indicates that it has approached the optimal result. Therefore, the current value of the angle and the value of the radius can be determined as the final parameters of the combustion structure. The combustion structure will be set to the above-mentioned final angle and final radius in the actual design process.

[0043] Through this embodiment, the initial value of the angle and the initial value of the radius of each sector-shaped sub-area are set, and the air utilization rate of each sector-shaped sub-area is calculated based on the initial value; when the air utilization rate is less than the preset threshold, the value of the angle and the value of the radius are reduced until the air utilization rate of the sector-shaped sub-area after the reduction is greater than or equal to the preset threshold, and the current value of the angle is determined as the final angle, and the current value of the radius is determined as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system. Compared with the prior art, in which the structure of the combustion chamber is not convenient for the full combustion of the fuel, the present application adjusts the structural parameters of the combustion system by setting the initial value and calculating the air utilization rate under the initial value condition, so that the adjusted structure of the combustion chamber is more conducive to the full combustion of the fuel. Therefore, it can solve the problem in the prior art that the structure of the combustion chamber is not convenient for the full combustion of the fuel, and achieve the effect of reasonably designing the structural parameters of the combustion chamber.

[0044] In the specific implementation process, the above step S202, when the air utilization rate is less than the preset threshold, reduces the value of the angle and the value of the radius until the air utilization rate of the fan-shaped sub-area after the reduction is greater than or equal to the preset threshold, can be implemented by the following steps: Step S2021: Determination step: When the air utilization rate is less than the preset threshold, reduce the value of the angle and the value of the radius to determine the air utilization rate of the fan-shaped sub-area after the reduction; Step S2022: Execute the determination step at least once until the air utilization rate is greater than or equal to the preset threshold, and obtain the current value of the angle and the current value of the radius. The method calculates the optimal structural parameters through the above steps, so that the value of the structural parameters can be quickly obtained through an iterative process.

[0045] Specifically, the iterative method in the above steps S2021 and S2022 can be adopted, that is, if the air utilization rate is less than the preset threshold, the values ​​of the angle and radius are reduced once. This process requires setting an iteration interval, subtracting the iteration interval value from the current angle value to obtain the value of the next angle, and similarly calculate the value of the next radius, and calculate the corresponding adjusted air utilization rate of the fan-shaped sub-area. When it is less than the preset threshold, continue the above iteration until the angle and radius values ​​corresponding to the condition that the air utilization rate is greater than or equal to the preset threshold are found. In actual application, the radius and angle that meet the above preset threshold can also be directly calculated. This application does not limit the specific method of calculating the structural parameters above.

[0046] In order to accurately determine the air utilization rate, the above step S201 determines the air utilization rate of each sector sub-area according to the initial value, which can be achieved by the following steps: step S2011: simulating each sector sub-area under the initial value condition; step S2012: obtaining the mapping relationship between the engine crankshaft angle and the excess air coefficient in each simulated sector sub-area, and determining the air utilization rate according to the mapping relationship. The method determines the air utilization rate through the above steps, so that the air utilization rate can be accurately determined.

[0047] In a specific implementation process, each of the sector-shaped sub-regions under the initial value condition is simulated, that is, simulation is performed according to the radius and angle of each sector-shaped sub-region to simulate a real combustion scene. Figure 7 The figure shows the schematic diagram of the air utilization rate of each sector sub-area under simulation. The horizontal axis represents the engine crankshaft angle °CA, and the vertical axis represents the excess air coefficient λ (λ<1). The curve area shown in the figure represents the air utilization rate. The smaller the curve area, the smaller the air utilization rate, which means that the richer mixture area is smaller, which is conducive to oil-gas mixing. Due to the differences in flow conditions in different areas of the cylinder in actual work, the air utilization rate in each sector sub-interval is different. Usually, the earlier the value approaches 0, the better, usually around 30°CA ATDC (30° crankshaft angle after top dead center). From Figure 7 It can be seen that the area of ​​space one is greater than the area of ​​space two, which is greater than the area of ​​space three, indicating that the relationship between the space utilization is space three < space two < space one, that is, at least space one needs to be adjusted. The adjustment method is to first adjust the parameters γ and the pit depth H of the combustion chamber mentioned in the above steps to determine the volume of each fan-shaped sub-area after adjustment. γ represents the angle between the two raised arc ridges, the smaller the angle, the smaller the fan-shaped area; H represents the depth of the pit, the smaller the pit, the shallower the pit.

[0048] In some optional embodiments, after obtaining the final angle and final radius of the fan-shaped sub-region, the method further includes: step S203: calculating the volume of the fan-shaped sub-region, and calculating the volume proportion of the fan-shaped sub-region according to the volume; step S204: determining the injection amount proportion of the fan-shaped sub-region according to the volume proportion, and determining the nozzle aperture of the injector according to the injection amount proportion, wherein the nozzle aperture is the final structural design parameter. The method also determines the parameter of the injector aperture in the combustion system through the above steps, making the structural parameters more complete to ensure the full combustion of the fuel.

[0049] Specifically, in order to match the corresponding fuel injection amount to the adjusted sector-shaped sub-area, the nozzle aperture of the injector needs to be set accordingly. Therefore, the volume ratio is calculated by calculating the volume of the adjusted sector-shaped sub-area, and then the injection amount ratio corresponding to the sector-shaped sub-area is calculated according to the same equation relationship between the volume ratio and the fuel amount ratio. The injection amount or fuel amount refers to the mass of the injected fuel, and then the corresponding nozzle aperture is calculated according to the mathematical relationship between the injection amount ratio and the nozzle aperture.

[0050] In order to accurately calculate the proportion of the injection amount, the above step S203 calculates the volume proportion of the sector-shaped sub-area according to the volume, which can be achieved by the following steps: obtaining the total volume of the combustion chamber, calculating the ratio of the volume of the sector-shaped sub-area to the total volume, and obtaining the volume proportion; the above step S204 determines the proportion of the injection amount of the sector-shaped sub-area according to the volume proportion, which can be achieved by the following steps: obtaining the total injection amount, calculating the product of the volume proportion and the total injection amount, and obtaining the injection amount proportion. The method performs calculations according to the corresponding relationship between the various parameters through the above steps, so that the volume proportion and the injection amount proportion can be accurately calculated.

[0051] In the specific implementation process, the proportion of the volume of the sector sub-area in the entire combustion chamber space is calculated, and the proportion of fuel in the area is determined according to the same proportion, that is, v1 / V=m1 / M. Among them, m1 is the injection amount corresponding to sector sub-area 1, and M is the total injection amount of a single cycle in the entire combustion chamber.

[0052] In some optional implementations, the above step S204 determines the nozzle aperture of the injector according to the injection amount ratio, which can be achieved by the following steps: Step S2041: According to the formula Calculate the aperture cross-sectional area of ​​the injector, wherein A is the aperture cross-sectional area, n is the engine speed where the plurality of sector sub-regions are located, m is the injection amount of each sector sub-region, μ is the flow coefficient of the aperture of the injector, v represents the injection speed of the injector, and t represents the injection duration; Step S2042: According to the formula The nozzle aperture of the injector is calculated, wherein i represents the number of the injectors and d represents the nozzle aperture. The method calculates the nozzle aperture of the injector through the above steps, so that the nozzle aperture corresponding to the adjusted fan-shaped sub-area can be accurately calculated.

[0053] Specifically, after determining the oil volume proportion of each sector sub-area, the rail pressure P and injection time t of each nozzle hole during the injection process are the same, so the aperture of each nozzle hole can be determined by the formula shown above. v is the injection speed, generally 300m / s~400m / s, i is the number of nozzle holes, and i=1 for a single hole.

[0054] In some optional implementations, the above step S201 sets the initial value of the angle and the initial value of the radius of each of the fan-shaped sub-areas, which can be achieved by the following steps: setting the initial value of the angle of any two of the fan-shaped sub-areas to be the same; setting the initial value of the radius of any two of the fan-shaped sub-areas to be the same. The method sets the initial value by the above steps, so that further adjustments can be made under the initial value conditions to improve the fuel injection efficiency.

[0055] In the specific implementation process, according to the uniform distribution of each sector-shaped sub-region of the combustion chamber, the initial calculation scheme is determined, that is, the initial value of the angle between any two of the sector-shaped sub-regions is the same, the initial value of the radius of any two of the sector-shaped sub-regions is the same, and the aperture of any two nozzles is also the same. The volume in each sector-shaped sub-region is calculated, and the combustion chamber is simulated. The equivalence ratio distribution and air utilization rate in each volume output by the preset output are used as evaluation criteria to analyze the oil and gas mixing in each sub-region. The distribution of the equivalence ratio represents the average equivalence ratio (Φ) in each small interval, and the calculation formula is the inverse of the excess air coefficient, that is, Φ=1 / λ; the air utilization rate is a volume ratio. For example, in a certain interval with a volume of v1, the grid volume with λ less than 1 is v, which means that the air utilization rate (λ<1)=v / v1. Based on the simulation calculation of the finite volume method, the calculation domain is divided into several small volumes, and the λ of each small volume is counted separately to obtain the corresponding v. In actual application, the initial value can also be set to a different value, that is, each sector sub-area is in a non-uniform distribution form, and then adjusted according to air utilization rate, etc.

[0056] The double-row hole solution of this scheme further improves the injector flow rate while using multiple holes to reduce smoke. In this way, different apertures are used. Since the penetration distances of the single nozzle holes of the injector are different, it is beneficial to reduce the interference between the oil beams, improve the air utilization rate in the cylinder, and thus improve the power and economy. The double-row hole technology solution matches the raised arc ridge combustion chamber. The arc ridge design reduces the interference of the oil beams, which is beneficial to speed up the combustion speed and fully burn. For the single combustion chamber structure space composed of two adjacent arc ridges, each oil beam corresponds to a combustion space (i.e., a fan-shaped sub-area). The aperture and combustion chamber volume are matched for each oil beam according to the volume size and the air utilization rate of the simulation results. It overcomes the shortcomings of the single-row hole injector structure and processing limitations, and the number of holes and flow cannot be continuously increased.

[0057] 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 method for determining the structural parameters of the combustion system of the present application will be described in detail below in conjunction with specific embodiments.

[0058] This embodiment relates to a specific method for determining the structural parameters of a combustion system, such as Figure 8 As shown, the following steps are included:

[0059] Step S1: according to the uniform distribution of the combustion chamber, determine the initial value, calculate the volume of each sector sub-region, simulate the combustion chamber, and calculate the air utilization rate of each sector sub-region;

[0060] Step S2: adjusting the structural parameters of the sector-shaped sub-region whose air utilization rate is less than a preset threshold, that is, reducing the value of the angle and the value of the radius, until the air utilization rate of the sector-shaped sub-region after the reduction is optimal, that is, greater than or equal to the preset threshold;

[0061] Step S3: calculating the proportion of the volume of the sector-shaped sub-region in the entire combustion chamber space, and determining the proportion of fuel in the region according to the same proportion;

[0062] Step S4: After determining the fuel proportion of each sector sub-area, the rail pressure P and injection time t of each injection hole during the injection process are the same, so the nozzle aperture of each injector can be calculated;

[0063] Step S5: Designing the actual structure of the combustion system according to the above structural parameters.

[0064] The present application embodiment also provides a device for determining the structural parameters of a combustion system. It should be noted that the device for determining the structural parameters of the combustion system of the present application embodiment can be used to execute the device for determining the structural parameters of the combustion system provided by the present application embodiment. The device is used to implement the above-mentioned embodiments and preferred implementation modes, 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 of a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware is also possible and conceived.

[0065] The following is an introduction to the device for determining the structural parameters of the combustion system provided in the embodiment of the present application.

[0066] Fig. 9 Schematic diagram of a device for determining structural parameters of a combustion system according to an embodiment of the present application. The combustion system includes a combustion chamber, an injector and a piston, wherein the combustion chamber includes a plurality of sector-shaped sub-areas, such as Fig. 9 As shown, the device comprises:

[0067] A first determining unit 10 is used to set an initial value of the angle and an initial value of the radius of each of the fan-shaped sub-areas, and determine the air utilization rate of each of the fan-shaped sub-areas according to the initial values;

[0068] Specifically, the structural diagram of the combustion chamber is as follows: Figure 3 As shown, the combustion chamber is divided into multiple sector-shaped sub-areas with the center of the piston in the combustion chamber system as the center of the circle and the radius from the inner wall of the combustion chamber to the center of the piston as V1 and V2. Each sector-shaped sub-area corresponds to an injector, and the injector sprays fuel to the corresponding sector-shaped sub-area. The piston is generally located in the middle of the combustion chamber. The injector is a double-row hole injector nozzle arrangement. The injector nozzle is divided into two rows, upper and lower, and the number of holes is not less than 10. The number of holes in this scheme is 16, 8 in the upper and lower rows, as shown in FIG. Figure 4 The angle between the oil beams in the upper row of holes is α, and the angle between the lower row is β. The angle between the upper and lower rows of nozzles can be arranged evenly or unevenly, and they are staggered, such as Figure 5 As shown. For the 16-hole uniformly distributed spray hole injector, its α and β are 45° respectively. For the asymmetric specific angle matching, it needs to be determined by calculation based on the combustion chamber profile. The aperture and oil volume distribution of the double-row holes need to be determined through simulation. According to the different oil beam landing areas, the combustion chamber is divided into 16 corresponding sector-shaped sub-areas. Each area corresponds to a spray hole that sprays fuel into the area. A raised arc ridge is set between adjacent areas. The raised arc ridge design consists of two adjacent protrusions and the piston surface. The volume of the sector-shaped area to the center of the piston is v1, and other similar spaces are v2 to v n As mentioned above Figure 3As shown. The volume of the entire combustion chamber is V, and the volume ratio of each space is v / V. The angle γ between the convex arc ridges of the asymmetric structure (that is, the angle of the fan-shaped sub-areas formed) is different, ranging from 15° to 45°, which is used to form different regional volumes. Targeted, and the pit depth H of each area (that is, the radius of the fan-shaped sub-area) is also different, generally ranging from H = (0.11~0.2) D, such as Figure 6 As shown, H1 and H2 represent the radius of two different fan-shaped sub-areas. For the combustion chamber profile of the symmetrical structure, the initial γ and pit depth H of each area of ​​the combustion chamber are the same value, so the volume of each area is the same, and the apertures of the injectors are also the same. In order to further improve the air utilization rate, this scheme designs the combustion chamber into an asymmetric structure, and the apertures of the injectors are different, so the corresponding fuel injection amount in each space is also different.

[0069] The second determination unit 20 is used to reduce the values ​​of the angle and the radius when the air utilization rate is less than a preset threshold value, until the air utilization rate of the fan-shaped sub-area after reduction is greater than or equal to the preset threshold value, determine the current value of the angle as the final angle, and determine the current value of the radius as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system.

[0070] Specifically, simulation is performed for each sector sub-area, the actual volume of the sector sub-area is simulated, the fuel injection amount under real conditions is simulated, and the air utilization rate is calculated. When the air utilization rate is less than the preset threshold, that is, the oil-gas mixing effect is not good, the value of the angle and the value of the radius are adjusted. Generally, the lower the air utilization rate, the smaller the value of the angle and the value of the radius of the corresponding sector sub-area need to be adjusted. The basis for adjustment is the comparison of air utilization rates in different spaces. The goal is to approach the optimal result. Usually H is adjusted to about 0.15D. The range of γ is within ±10°. Until the air utilization rate of the sector sub-area after reduction is greater than or equal to the preset threshold, it indicates that it has approached the optimal result. Therefore, the current value of the angle and the value of the radius can be determined as the final parameters of the combustion structure. The combustion structure will be set to the above-mentioned final angle and final radius in the actual design process.

[0071] Through this embodiment, the initial value of the angle and the initial value of the radius of each sector-shaped sub-area are set, and the air utilization rate of each sector-shaped sub-area is calculated based on the initial value; when the air utilization rate is less than the preset threshold, the value of the angle and the value of the radius are reduced until the air utilization rate of the sector-shaped sub-area after the reduction is greater than or equal to the preset threshold, and the current value of the angle is determined as the final angle, and the current value of the radius is determined as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system. Compared with the prior art, in which the structure of the combustion chamber is not convenient for the full combustion of the fuel, the present application adjusts the structural parameters of the combustion system by setting the initial value and calculating the air utilization rate under the initial value condition, so that the adjusted structure of the combustion chamber is more conducive to the full combustion of the fuel. Therefore, it can solve the problem in the prior art that the structure of the combustion chamber is not convenient for the full combustion of the fuel, and achieve the effect of reasonably designing the structural parameters of the combustion chamber.

[0072] In a specific implementation process, the second determination unit includes a first calculation module and an execution module, wherein the first calculation module is used to execute the determination step: when the air utilization rate is less than the preset threshold, the value of the angle and the value of the radius are reduced to determine the air utilization rate of the fan-shaped sub-area after the reduction; the execution module is used to execute the determination step at least once until the air utilization rate is greater than or equal to the preset threshold, and the current value of the angle and the current value of the radius are obtained. The device calculates the optimal structural parameters through the above steps, so that the value of the structural parameters can be quickly obtained through an iterative process.

[0073] Specifically, the above-mentioned iterative method can be adopted, that is, when the air utilization rate is less than the preset threshold, the values ​​of the angle and radius are reduced once. This process requires setting an iteration interval, subtracting the iteration interval value from the current angle value to obtain the value of the next angle, and similarly calculate the value of the next radius, and calculate the corresponding adjusted air utilization rate of the fan-shaped sub-area. When it is less than the preset threshold, continue the above iteration until the angle and radius values ​​corresponding to the condition that the air utilization rate is greater than or equal to the preset threshold are found. In actual application, the radius and angle that meet the above-mentioned preset threshold can also be directly calculated. This application does not limit the specific method of calculating the structural parameters above.

[0074] In order to accurately determine the air utilization rate, the first determination unit includes a simulation module and a determination module, wherein the simulation module is used to simulate each of the sector sub-areas under the initial value condition; the determination module is used to obtain the mapping relationship between the engine crankshaft angle and the excess air coefficient in each simulated sector sub-area, and determine the air utilization rate according to the mapping relationship. The device determines the air utilization rate through the above steps, so that the air utilization rate can be accurately determined.

[0075] In a specific implementation process, each of the sector-shaped sub-regions under the initial value condition is simulated, that is, simulation is performed according to the radius and angle of each sector-shaped sub-region to simulate a real combustion scene. Figure 7 The figure shows the schematic diagram of the air utilization rate of each sector sub-area under simulation. The horizontal axis represents the engine crankshaft angle °CA, and the vertical axis represents the excess air coefficient λ (λ<1). The curve area shown in the figure represents the air utilization rate. The smaller the curve area, the smaller the air utilization rate, which means that the richer mixture area is smaller, which is conducive to oil-gas mixing. Due to the differences in flow conditions in different areas of the cylinder in actual work, the air utilization rate in each sector sub-interval is different. Usually, the earlier the value approaches 0, the better, usually around 30°CA ATDC (30° crankshaft angle after top dead center). From Figure 7 It can be seen that the area of ​​space one is greater than the area of ​​space two, which is greater than the area of ​​space three, indicating that the relationship between the space utilization ratios is space three < space two < space one, that is, at least space one needs to be adjusted. The adjustment device is the first step mentioned in the above steps to adjust the parameters γ and the pit depth H of the combustion chamber to determine the volume of each fan-shaped sub-area after adjustment. γ represents the angle between the two raised arc ridges, the smaller the angle, the smaller the fan-shaped area; H represents the depth of the pit, the smaller the pit, the shallower the pit.

[0076] In some optional embodiments, after obtaining the final angle and final radius of the fan-shaped sub-region, the device further includes a first calculation unit and a third determination unit, wherein the first calculation unit is used to calculate the volume of the fan-shaped sub-region and calculate the volume proportion of the fan-shaped sub-region according to the volume; the third determination unit is used to determine the injection amount proportion of the fan-shaped sub-region according to the volume proportion, and determine the nozzle aperture of the injector according to the injection amount proportion, wherein the nozzle aperture is the final structural design parameter. The device also determines the parameter of the injector aperture in the combustion system through the above steps, making the structural parameters more complete to ensure the full combustion of the fuel.

[0077] Specifically, in order to match the corresponding fuel injection amount to the adjusted sector-shaped sub-area, the nozzle aperture of the injector needs to be set accordingly. Therefore, the volume ratio is calculated by calculating the volume of the adjusted sector-shaped sub-area, and then the injection amount ratio corresponding to the sector-shaped sub-area is calculated according to the same equation relationship between the volume ratio and the fuel amount ratio. The injection amount or fuel amount refers to the mass of the injected fuel, and then the corresponding nozzle aperture is calculated according to the mathematical relationship between the injection amount ratio and the nozzle aperture.

[0078] In order to accurately calculate the proportion of the injection amount, the first calculation unit includes a second calculation module, which is used to obtain the total volume of the combustion chamber, calculate the ratio of the volume of the sector sub-area to the total volume, and obtain the volume proportion; the third determination unit includes a third calculation module, which is used to obtain the total injection amount, calculate the product of the volume proportion and the total injection amount, and obtain the injection amount proportion. The device performs calculations according to the corresponding relationship between various parameters through the above steps, so that the volume proportion and the injection amount proportion can be accurately calculated.

[0079] In the specific implementation process, the proportion of the volume of the sector sub-area in the entire combustion chamber space is calculated, and the proportion of fuel in the area is determined according to the same proportion, that is, v1 / V=m1 / M. Among them, m1 is the injection amount corresponding to sector sub-area 1, and M is the total injection amount of a single cycle in the entire combustion chamber.

[0080] In some optional implementations, the third determining unit in the above step includes a fourth calculating module and a fifth calculating module, and the fourth calculating module is used to calculate the value of the formula Calculate the aperture cross-sectional area of ​​the injector, wherein A is the aperture cross-sectional area, n is the engine speed where the plurality of sector sub-regions are located, m is the injection amount of each sector sub-region, μ is the flow coefficient of the aperture of the injector, v represents the injection speed of the injector, and t represents the injection duration; the fifth calculation module is used to calculate the aperture cross-sectional area of ​​the injector according to the formula The nozzle aperture of the injector is calculated, wherein i represents the number of the injectors and d represents the nozzle aperture. The device calculates the nozzle aperture of the injector through the above steps, so that the nozzle aperture corresponding to the adjusted fan-shaped sub-area can be accurately calculated.

[0081] Specifically, after determining the oil volume proportion of each sector sub-area, the rail pressure P and injection time t of each nozzle hole during the injection process are the same, so the aperture of each nozzle hole can be determined by the formula shown above. v is the injection speed, generally 300m / s~400m / s, i is the number of nozzle holes, and i=1 for a single hole.

[0082] In some optional embodiments, the first determination unit further includes a first setting module and a second setting module, wherein the first setting module is used to set the initial value of the angle between any two of the fan-shaped sub-areas to be the same; and the second setting module is used to set the initial value of the radius between any two of the fan-shaped sub-areas to be the same. The device sets the initial value through the above steps, so that further adjustments can be made under the initial value conditions to improve the injection efficiency of the fuel.

[0083] In the specific implementation process, according to the uniform distribution of each sector-shaped sub-region of the combustion chamber, the initial calculation scheme is determined, that is, the initial value of the angle between any two of the sector-shaped sub-regions is the same, the initial value of the radius of any two of the sector-shaped sub-regions is the same, and the aperture of any two nozzles is also the same. The volume in each sector-shaped sub-region is calculated, and the combustion chamber is simulated. The equivalence ratio distribution and air utilization rate in each volume output by the preset output are used as evaluation criteria to analyze the oil and gas mixing in each sub-region. The distribution of the equivalence ratio represents the average equivalence ratio (Φ) in each small interval, and the calculation formula is the inverse of the excess air coefficient, that is, Φ=1 / λ; the air utilization rate is a volume ratio. For example, in a certain interval with a volume of v1, the grid volume with λ less than 1 is v, which means that the air utilization rate (λ<1)=v / v1. Based on the simulation calculation of the finite volume method, the calculation domain is divided into several small volumes, and the λ of each small volume is counted separately to obtain the corresponding v. In actual application, the initial value can also be set to a different value, that is, each sector sub-area is in a non-uniform distribution form, and then adjusted according to air utilization rate, etc.

[0084] The double-row hole solution of this scheme further improves the injector flow rate while using multiple holes to reduce smoke. In this way, different apertures are used. Since the penetration distances of the single nozzle holes of the injector are different, it is beneficial to reduce the interference between the oil beams, improve the air utilization rate in the cylinder, and thus improve the power and economy. The double-row hole technology solution matches the raised arc ridge combustion chamber. The arc ridge design reduces the interference of the oil beams, which is beneficial to speed up the combustion speed and fully burn. For the single combustion chamber structure space composed of two adjacent arc ridges, each oil beam corresponds to a combustion space (i.e., a fan-shaped sub-area). The aperture and combustion chamber volume are matched for each oil beam according to the volume size and the air utilization rate of the simulation results. It overcomes the shortcomings of the single-row hole injector structure and processing limitations, and the number of holes and flow cannot be continuously increased.

[0085] The device for determining the structural parameters of the combustion system includes a processor and a memory. The first determination unit, the second determination unit, etc. are 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.

[0086] The processor includes a kernel, which calls the corresponding program unit from the memory. One or more kernels can be set, and the structural parameters of the combustion system are determined by adjusting the kernel parameters.

[0087] 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.

[0088] An embodiment of the present invention provides a computer-readable storage medium, which includes a stored program, wherein when the program is run, the device where the computer-readable storage medium is located is controlled to execute a method for determining structural parameters of the combustion system.

[0089] Specifically, the method for determining the structural parameters of the combustion system includes:

[0090] Step S201, setting an initial value of the angle and the initial value of the radius of each of the fan-shaped sub-areas, and determining the air utilization rate of each of the fan-shaped sub-areas according to the initial values;

[0091] Specifically, the structural diagram of the combustion chamber is as follows: Figure 3 As shown, the combustion chamber is divided into multiple sector-shaped sub-areas with the center of the piston in the combustion chamber system as the center of the circle and the radius from the inner wall of the combustion chamber to the center of the piston as V1 and V2. Each sector-shaped sub-area corresponds to an injector, and the injector sprays fuel to the corresponding sector-shaped sub-area. The piston is generally located in the middle of the combustion chamber. The injector is a double-row hole injector nozzle arrangement. The injector nozzle structure is distributed in two rows, with no less than 10 holes. The number of holes in this scheme is 16, with 8 holes in the upper and lower rows, as shown in FIG. Figure 4 The angle between the oil beams in the upper row of holes is α, and the angle between the oil beams in the lower row is β. The angle between the upper and lower rows of nozzle holes can be arranged uniformly or non-uniformly, and they are staggered, such as Figure 5 As shown. For the 16-hole uniformly distributed spray hole injector, its α and β are 45° respectively. For the asymmetric specific angle matching, it needs to be determined by calculation based on the combustion chamber profile. The aperture and oil volume distribution of the double-row holes need to be determined through simulation. According to the different oil beam landing areas, the combustion chamber is divided into 16 corresponding sector-shaped sub-areas. Each area corresponds to a spray hole that sprays fuel into the area. A raised arc ridge is set between adjacent areas. The raised arc ridge design consists of two adjacent protrusions and the piston surface. The volume of the sector-shaped area to the center of the piston is v1, and other similar spaces are v2 to v n As mentioned above Figure 3As shown. The volume of the entire combustion chamber is V, and the volume ratio of each space is v / V. The angle γ between the raised arc ridges of the asymmetric structure (that is, the angle of the fan-shaped sub-areas formed) is different, ranging from 15° to 45°, which is used to form different regional volumes. Targeted, and the pit depth H of each area (that is, the radius of the fan-shaped sub-area) is also different, generally ranging from H = (0.11~0.2) D. The schematic diagram of the pit depth structure of the combustion chamber is shown in Figure 6 As shown, H1 and H2 represent the radius of two different fan-shaped sub-areas. For the combustion chamber profile of the symmetrical structure, the initial γ and pit depth H of each area of ​​the combustion chamber are the same value, so the volume of each area is the same, and the apertures of the injectors are also the same. In order to further improve the air utilization rate, this scheme designs the combustion chamber into an asymmetric structure, and the apertures of the injectors are different, so the corresponding fuel injection amount in each space is also different.

[0092] Step S202, when the air utilization rate is less than a preset threshold, reduce the value of the angle and the value of the radius until the air utilization rate of the fan-shaped sub-area after reduction is greater than or equal to the preset threshold, determine the current value of the angle as the final angle, and determine the current value of the radius as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system.

[0093] Specifically, simulation is performed for each sector sub-area, the actual volume of the sector sub-area is simulated, the fuel injection amount under real conditions is simulated, and the air utilization rate is calculated. When the air utilization rate is less than the preset threshold, that is, the oil-gas mixing effect is not good, the value of the angle and the value of the radius are adjusted. Generally, the lower the air utilization rate, the smaller the value of the angle and the value of the radius of the corresponding sector sub-area need to be adjusted. The basis for adjustment is the comparison of air utilization rates in different spaces. The goal is to approach the optimal result. Usually H is adjusted to about 0.15D. The range of γ is within ±10°. Until the air utilization rate of the sector sub-area after reduction is greater than or equal to the preset threshold, it indicates that it has approached the optimal result. Therefore, the current value of the angle and the value of the radius can be determined as the final parameters of the combustion structure. The combustion structure will be set to the above-mentioned final angle and final radius in the actual design process.

[0094] An embodiment of the present invention provides a system for determining structural parameters of a combustion system, wherein the combustion system includes a combustion chamber, an injector, and a piston, wherein the combustion chamber includes a plurality of fan-shaped sub-areas; and a controller includes a processor, a memory, and a program stored in the memory and executable on the processor, wherein when the processor executes the program, at least the following steps are implemented:

[0095] Step S201, setting an initial value of the angle and the initial value of the radius of each of the fan-shaped sub-areas, and determining the air utilization rate of each of the fan-shaped sub-areas according to the initial values;

[0096] Specifically, the structural diagram of the combustion chamber is as follows: Figure 3 As shown, the combustion chamber is divided into multiple sector-shaped sub-areas with the center of the piston in the combustion chamber system as the center of the circle and the radius from the inner wall of the combustion chamber to the center of the piston as V1 and V2. Each sector-shaped sub-area corresponds to an injector, and the injector sprays fuel to the corresponding sector-shaped sub-area. The piston is generally located in the middle of the combustion chamber. The injector is a double-row hole injector nozzle arrangement. The injector nozzle is divided into two rows, upper and lower, and the number of holes is not less than 10. The number of holes in this scheme is 16, 8 in the upper and lower rows, as shown in FIG. Figure 4 The angle between the oil beams in the upper row of holes is α, and the angle between the lower row is β. The angle between the upper and lower rows of nozzles can be arranged evenly or unevenly, and they are staggered, such as Figure 5 As shown. For the 16-hole uniformly distributed spray hole injector, its α and β are 45° respectively. For the asymmetric specific angle matching, it needs to be determined by calculation based on the combustion chamber profile. The aperture and oil volume distribution of the double-row holes need to be determined through simulation. According to the different oil beam landing areas, the combustion chamber is divided into 16 corresponding sector-shaped sub-areas. Each area corresponds to a spray hole that sprays fuel into the area. A raised arc ridge is set between adjacent areas. The raised arc ridge design consists of two adjacent protrusions and the piston surface. The volume of the sector-shaped area to the center of the piston is v1, and other similar spaces are v2 to v n As mentioned above Figure 3 As shown. The volume of the entire combustion chamber is V, and the volume ratio of each space is v / V. The angle γ between the convex arc ridges of the asymmetric structure (that is, the angle of the fan-shaped sub-areas formed) is different, ranging from 15° to 45°, which is used to form different regional volumes. Targeted, and the pit depth H of each area (that is, the radius of the fan-shaped sub-area) is also different, generally ranging from H = (0.11~0.2) D, such as Figure 6 As shown, H1 and H2 represent the radius of two different fan-shaped sub-areas. For the combustion chamber profile of the symmetrical structure, the initial γ and pit depth H of each area of ​​the combustion chamber are the same value, so the volume of each area is the same, and the apertures of the injectors are also the same. In order to further improve the air utilization rate, this scheme designs the combustion chamber into an asymmetric structure, and the apertures of the injectors are different, so the corresponding fuel injection amount in each space is also different.

[0097] Step S202, when the air utilization rate is less than a preset threshold, reduce the value of the angle and the value of the radius until the air utilization rate of the fan-shaped sub-area after reduction is greater than or equal to the preset threshold, determine the current value of the angle as the final angle, and determine the current value of the radius as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system.

[0098] Specifically, simulation is performed for each sector sub-area, the actual volume of the sector sub-area is simulated, the fuel injection amount under real conditions is simulated, and the air utilization rate is calculated. When the air utilization rate is less than the preset threshold, that is, the oil-gas mixing effect is not good, the value of the angle and the value of the radius are adjusted. Generally, the lower the air utilization rate, the smaller the value of the angle and the value of the radius of the corresponding sector sub-area need to be adjusted. The basis for adjustment is the comparison of air utilization rates in different spaces. The goal is to approach the optimal result. Usually H is adjusted to about 0.15D. The range of γ is within ±10°. Until the air utilization rate of the sector sub-area after reduction is greater than or equal to the preset threshold, it indicates that it has approached the optimal result. Therefore, the current value of the angle and the value of the radius can be determined as the final parameters of the combustion structure. The combustion structure will be set to the above-mentioned final angle and final radius in the actual design process.

[0099] The present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the method described in each embodiment of the present application:

[0100] Step S201, setting an initial value of the angle and the initial value of the radius of each of the fan-shaped sub-areas, and determining the air utilization rate of each of the fan-shaped sub-areas according to the initial values;

[0101] Specifically, the structural diagram of the combustion chamber is as follows: Figure 3 As shown, the combustion chamber is divided into multiple sector-shaped sub-areas with the center of the piston in the combustion chamber system as the center of the circle and the radius from the inner wall of the combustion chamber to the center of the piston as V1 and V2. Each sector-shaped sub-area corresponds to an injector, and the injector sprays fuel to the corresponding sector-shaped sub-area. The piston is generally located in the middle of the combustion chamber. The injector is a double-row hole injector nozzle arrangement. The injector nozzle is divided into two rows, upper and lower, and the number of holes is not less than 10. The number of holes in this scheme is 16, 8 in the upper and lower rows, as shown in FIG. Figure 4 The angle between the oil beams in the upper row of holes is α, and the angle between the lower row is β. The angle between the upper and lower rows of nozzles can be arranged evenly or unevenly, and they are staggered, such as Figure 5As shown. For the 16-hole uniformly distributed spray hole injector, its α and β are 45° respectively. For the asymmetric specific angle matching, it needs to be determined by calculation based on the combustion chamber profile. The aperture and oil volume distribution of the double-row holes need to be determined through simulation. According to the different oil beam landing areas, the combustion chamber is divided into 16 corresponding sector-shaped sub-areas. Each area corresponds to a spray hole that sprays fuel into the area. A raised arc ridge is set between adjacent areas. The raised arc ridge design consists of two adjacent protrusions and the piston surface. The volume of the sector-shaped area to the center of the piston is v1, and other similar spaces are v2 to v n As mentioned above Figure 3 As shown. The volume of the entire combustion chamber is V, and the volume ratio of each space is v / V. The angle γ between the convex arc ridges of the asymmetric structure (that is, the angle of the fan-shaped sub-areas formed) is different, ranging from 15° to 45°, which is used to form different regional volumes. Targeted, and the pit depth H of each area (that is, the radius of the fan-shaped sub-area) is also different, generally ranging from H = (0.11~0.2) D, such as Figure 6 As shown, H1 and H2 represent the radius of two different fan-shaped sub-areas. For the combustion chamber profile of the symmetrical structure, the initial γ and pit depth H of each area of ​​the combustion chamber are the same value, so the volume of each area is the same, and the apertures of the injectors are also the same. In order to further improve the air utilization rate, this scheme designs the combustion chamber into an asymmetric structure, and the apertures of the injectors are different, so the corresponding fuel injection amount in each space is also different.

[0102] Step S202, when the air utilization rate is less than a preset threshold, reduce the value of the angle and the value of the radius until the air utilization rate of the fan-shaped sub-area after reduction is greater than or equal to the preset threshold, determine the current value of the angle as the final angle, and determine the current value of the radius as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system.

[0103] Specifically, simulation is performed for each sector sub-area, the actual volume of the sector sub-area is simulated, the fuel injection amount under real conditions is simulated, and the air utilization rate is calculated. When the air utilization rate is less than the preset threshold, that is, the oil-gas mixing effect is not good, the value of the angle and the value of the radius are adjusted. Generally, the lower the air utilization rate, the smaller the value of the angle and the value of the radius of the corresponding sector sub-area need to be adjusted. The basis for adjustment is the comparison of air utilization rates in different spaces. The goal is to approach the optimal result. Usually H is adjusted to about 0.15D. The range of γ is within ±10°. Until the air utilization rate of the sector sub-area after reduction is greater than or equal to the preset threshold, it indicates that it has approached the optimal result. Therefore, the current value of the angle and the value of the radius can be determined as the final parameters of the combustion structure. The combustion structure will be set to the above-mentioned final angle and final radius in the actual design process.

[0104] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general 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 here, 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.

[0105] 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 combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0106] 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.

[0107] 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.

[0108] 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.

[0109] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0110] 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.

[0111] 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.

[0112] 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.

[0113] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0114] 1) In the method for determining the structural parameters of the combustion system of the present application, the initial value of the angle and the initial value of the radius of each fan-shaped sub-area are set, and the air utilization rate of each fan-shaped sub-area is calculated based on the initial value; when the air utilization rate is less than the preset threshold, the value of the angle and the value of the radius are reduced until the air utilization rate of the fan-shaped sub-area after the reduction is greater than or equal to the preset threshold, and the current value of the angle is determined as the final angle, and the current value of the radius is determined as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system. Compared with the prior art, in which the structure of the combustion chamber is not convenient for the full combustion of the fuel, the present application adjusts the structural parameters of the combustion system by setting the initial value and calculating the air utilization rate under the initial value condition, so that the adjusted structure of the combustion chamber is more conducive to the full combustion of the fuel. Therefore, it is possible to solve the problem in the prior art that the structure of the combustion chamber is not convenient for the full combustion of the fuel, and achieve the effect of reasonably designing the structural parameters of the combustion chamber.

[0115] 2) In the device for determining the structural parameters of the combustion system of the present application, the initial value of the angle and the initial value of the radius of each fan-shaped sub-area are set, and the air utilization rate of each fan-shaped sub-area is calculated based on the initial value; when the air utilization rate is less than the preset threshold, the value of the angle and the value of the radius are reduced until the air utilization rate of the fan-shaped sub-area after the reduction is greater than or equal to the preset threshold, and the current value of the angle is determined as the final angle, and the current value of the radius is determined as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system. Compared with the prior art, in which the structure of the combustion chamber is not convenient for the full combustion of the fuel, the present application adjusts the structural parameters of the combustion system by setting the initial value and calculating the air utilization rate under the initial value condition, so that the adjusted structure of the combustion chamber is more conducive to the full combustion of the fuel. Therefore, it is possible to solve the problem in the prior art that the structure of the combustion chamber is not convenient for the full combustion of the fuel, and achieve the effect of reasonably designing the structural parameters of the combustion chamber.

[0116] 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 determining structural parameters of a combustion system, characterized in that: The combustion system includes a combustion chamber, a fuel injector and a piston, wherein the combustion chamber includes a plurality of sector-shaped sub-areas, including: Setting an initial value of the angle and an initial value of the radius of each of the fan-shaped sub-areas, and determining the air utilization rate of each of the fan-shaped sub-areas according to the initial values; When the air utilization rate is less than a preset threshold, the values ​​of the angle and the radius are reduced until the air utilization rate of the fan-shaped sub-area after the reduction is greater than or equal to the preset threshold, and the current value of the angle is determined as the final angle, and the current value of the radius is determined as the final radius, wherein the final angle and the final radius are the final structural design parameters of the combustion system; Determining the air utilization rate of each of the sector-shaped sub-areas according to the initial value includes: Perform simulation on each of the sector-shaped sub-regions under the initial value condition; Acquire a mapping relationship between an engine crankshaft angle and an excess air coefficient in each simulation sector sub-area, and determine the air utilization rate according to the mapping relationship; After obtaining the final angle and the final radius of the sector-shaped sub-area, the method further includes: Calculating the volume of the sector-shaped sub-region, and calculating the volume ratio of the sector-shaped sub-region according to the volume; Determine the fuel injection amount ratio of the fan-shaped sub-area according to the volume ratio, and determine the nozzle aperture of the injector according to the fuel injection amount ratio, wherein the nozzle aperture is the final structural design parameter; Determining the nozzle aperture of the injector according to the fuel injection amount ratio includes: According to the formula Calculating the aperture cross-sectional area of ​​the injector, wherein A is the aperture cross-sectional area, n is the rotation speed of the engine where the plurality of sector-shaped sub-regions are located, m is the injection amount of each sector-shaped sub-region, μ is the flow coefficient of the aperture of the injector, v represents the injection speed of the injector, and t represents the injection duration; According to the formula The nozzle aperture of the fuel injector is calculated, wherein i represents the number of the fuel injectors and d represents the nozzle aperture.

2. The method for determining the structural parameters of a combustion system according to claim 1, characterized in that: When the air utilization rate is less than a preset threshold, reducing the value of the angle and the value of the radius until the air utilization rate of the sector sub-area after the reduction is greater than or equal to the preset threshold, including: Determining step: when the air utilization rate is less than the preset threshold, reducing the value of the angle and the value of the radius, and determining the air utilization rate of the fan-shaped sub-area after the reduction; The determining step is performed at least once until the air utilization rate is greater than or equal to the preset threshold, and the current value of the angle and the current value of the radius are obtained.

3. The method for determining the structural parameters of a combustion system according to claim 1, characterized in that: Calculating the volume proportion of the sector-shaped sub-area according to the volume includes: Acquiring the total volume of the combustion chamber, calculating the ratio of the volume of the sector-shaped sub-region to the total volume, and obtaining the volume proportion; Determining the fuel injection amount proportion of the sector sub-area according to the volume proportion includes: The total fuel injection amount is obtained, and the product of the volume percentage and the total fuel injection amount is calculated to obtain the fuel injection amount percentage.

4. The method for determining structural parameters of a combustion system according to claim 1, characterized in that: Setting the initial value of the angle and the initial value of the radius of each of the fan-shaped sub-areas includes: Setting the initial value of the angle between any two of the fan-shaped sub-areas to be the same; The initial values ​​of the radii of any two of the fan-shaped sub-areas are set to be the same.

5. A device for determining structural parameters of a combustion system, characterized in that: The combustion system includes a combustion chamber, a fuel injector and a piston, wherein the combustion chamber includes a plurality of sector-shaped sub-areas, including: A first determining unit is used to set an initial value of the angle and an initial value of the radius of each of the fan-shaped sub-areas, and determine the air utilization rate of each of the fan-shaped sub-areas according to the initial values; a second determination unit, configured to reduce the value of the angle and the value of the radius when the air utilization rate is less than a preset threshold value, until the air utilization rate of the fan-shaped sub-area after the reduction is greater than or equal to the preset threshold value, determine the current value of the angle as the final angle, and determine the current value of the radius as the final radius, wherein the final angle and the final radius are final structural design parameters of the combustion system; The first determining unit includes: A simulation module, used for simulating each of the sector-shaped sub-areas under the initial value condition; A determination module, used for obtaining a mapping relationship between an engine crankshaft angle and an excess air coefficient in each simulated sector sub-area, and determining the air utilization rate according to the mapping relationship; After obtaining the final angle and the final radius of the sector-shaped sub-area, the device further includes: A first calculation unit, configured to calculate the volume of the sector-shaped sub-region, and calculate the volume ratio of the sector-shaped sub-region according to the volume; a third determining unit, configured to determine the fuel injection amount ratio of the sector-shaped sub-area according to the volume ratio, and determine the nozzle aperture of the injector according to the fuel injection amount ratio, wherein the nozzle aperture is the final structural design parameter; The third determining unit includes: The fourth calculation module is used to calculate the Calculating the aperture cross-sectional area of ​​the injector, wherein A is the aperture cross-sectional area, n is the rotation speed of the engine where the plurality of sector-shaped sub-regions are located, m is the injection amount of each sector-shaped sub-region, μ is the flow coefficient of the aperture of the injector, v represents the injection speed of the injector, and t represents the injection duration; The fifth calculation module is used to calculate the The nozzle aperture of the fuel injector is calculated, wherein i represents the number of the fuel injectors and d represents the nozzle aperture.

6. 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 for determining the structural parameters of the combustion system according to any one of claims 1 to 4.

7. A system for determining structural parameters of a combustion system, characterized in that: include: A combustion system, comprising a combustion chamber, a fuel injector and a piston, wherein the combustion chamber comprises a plurality of sector-shaped sub-areas; A controller 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 a method for determining structural parameters of the combustion system described in any one of claims 1 to 4.

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