Self-adaptive variable swirl ratio diesel engine combustion system

Abstract

The invention provides a self-adaptive variable swirl ratio diesel engine combustion system which comprises a swirl ratio adjusting device arranged on an air cylinder, and the swirl ratio adjusting device comprises an external source high-pressure gas introduction device and an auxiliary oil injection device; and the diesel engine control unit controls the external source high-pressure gas introduction device or the auxiliary oil injection device to act, and generated high-speed airflow tangentially enters a main combustion chamber of the air cylinder through a high-speed jet flow channel, so that the high-speed airflow and an original air inlet vortex flow are in the same direction or opposite directions, and then the vortex ratio in the cylinder is adjusted. According to the self-adaptive variable swirl ratio diesel engine combustion system, the oil-gas mixing quality in a cylinder can be improved, the emission performance can be improved, the heat efficiency can be improved, the oil-gas mixing energy requirement of a diesel engine under all working conditions can be met, and harmful substance emission under transient working conditions can be reduced.

Description

Technical Field

[0001] This application belongs to the technical field of diesel engine combustion, and particularly relates to an adaptive variable swirl ratio diesel engine combustion system. Background Art

[0002] Due to the advantages of strong power, good economy and high reliability of diesel engines, they are still the main power sources in the fields of construction machinery, agricultural machinery, commercial vehicles, etc. The air motion state in the cylinder of a semi-open combustion chamber diesel engine plays a crucial and indispensable role in the fuel atomization process, the mixing uniformity of fuel and air, and their subsequent combustion characteristics. Especially when the cylinder diameter of the diesel engine is in a relatively small size range, the fuel atomization effect and combustion process largely depend on the swirl intensity, structure and distribution characteristics formed in the cylinder during the intake process.

[0003] Under different load conditions, the oil-gas mixing characteristics of diesel engines show significant differences. At low load conditions, the air volume in the cylinder is relatively sufficient, but the fuel injection volume is small, and at this time, the demand for oil-gas mixing energy is relatively low. As the load gradually increases, the fuel volume entering the cylinder increases, and in order to achieve a good mixing effect, the demand for mixing energy increases significantly. Therefore, precisely regulating the in-cylinder oil-gas mixing energy for different load conditions is of great significance for achieving efficient and clean combustion under all operating conditions.

[0004] In the actual daily operation of vehicles, the vast majority are transient operating conditions. Due to the limitation of the inertia of the turbocharger, the air volume entering the cylinder cannot match the change in the fuel injection volume in a timely manner, thereby destroying the oil-gas mixing ratio. Moreover, the airflow movement in the combustion chamber becomes more complex and unstable under transient operating conditions, affecting the atomization and diffusion of fuel and hindering the uniform mixing of oil and gas. Therefore, during the transient operating condition process, the output power of the diesel engine is unstable, the torque is correspondingly sluggish, and a large amount of harmful pollutants such as hydrocarbons (HC), carbon monoxide (CO) and particulate matter (PM) are generated, causing serious pollution to the environment. Summary of the Invention

[0005] In view of this, this application aims to propose an adaptive variable swirl ratio diesel engine combustion system to adaptively adjust the swirl ratio according to the transient operating conditions of the diesel engine, reduce the harmful emissions level under transient operating conditions, and enable the diesel engine to meet the requirements of emission regulations.

[0006] To achieve the above object, the technical solution of this application is realized as follows: This application provides an adaptive variable swirl ratio diesel engine combustion system, including: A swirl ratio adjustment device, the swirl ratio adjustment device is arranged on the cylinder, wherein the swirl ratio adjustment device includes an external source high-pressure gas introduction device and an auxiliary fuel injection device; A diesel engine control unit controls the operation of the external high-pressure gas introduction device or the auxiliary fuel injection device. The high-speed air flow generated enters the main combustion chamber of the cylinder tangentially through the high-speed jet channel, so that the high-speed air flow is in the same or opposite direction as the intake swirl of the original engine, thereby adjusting the in-cylinder swirl ratio.

[0007] Further, a number of independent chamber structures are arranged in the cylinder head area of the cylinder. An adapter is nested in the independent chamber, and an auxiliary combustion chamber is reserved in the adapter. An auxiliary fuel injector is installed in the auxiliary combustion chamber, and the auxiliary fuel injector is connected to the fuel supply system and the control unit; The auxiliary combustion chamber is communicated with the main combustion chamber.

[0008] Further, the auxiliary combustion chamber has a multi-stage stepped structure, and its bottom is communicated with the main combustion chamber through a high-speed jet channel.

[0009] Further, the high-speed jet channel includes a first jet channel and a second jet channel. The first jet channel is in the opposite direction to the intake swirl of the original engine, and the second jet channel is in the same direction as the intake swirl of the original engine.

[0010] Further, the diesel engine control unit controls the auxiliary fuel injector to inject fuel into the auxiliary combustion chamber. The fuel starts to burn in the auxiliary combustion chamber and builds pressure. A pressure difference is generated between the auxiliary combustion chamber and the main combustion chamber, so that the gas enters the main combustion chamber in a tangential jet form along the high-speed jet channel from the auxiliary combustion chamber, and the jet direction is controlled to be in the same or opposite direction as the intake swirl of the original engine, thereby adjusting the in-cylinder swirl ratio.

[0011] Further, the external high-pressure gas introduction device includes a high-pressure gas tank. The high-pressure gas tank is connected to the main combustion chamber of the cylinder through a connecting pipe. The outlet direction of the connecting pipe is tangentially arranged in the main combustion chamber.

[0012] Further, an electronically controlled valve is installed on the connecting pipe to control the injection of high-pressure gas in the high-pressure gas tank into the main combustion chamber.

[0013] Further, the diesel engine control unit controls the operation of the electronically controlled valve. The high-pressure gas is injected from the high-pressure gas tank into the main combustion chamber, and the injection direction of the high-pressure gas is controlled to be in the same or opposite direction as the intake swirl of the original engine, thereby adjusting the in-cylinder swirl ratio.

[0014] Compared with the prior art, the self-adaptive variable swirl ratio diesel engine combustion system described in this application has the following beneficial effects: (1) Improve the fuel-air mixing quality: realize flexible adjustment of the intake swirl ratio under all working conditions, accurately control the in-cylinder mixing energy according to the working condition requirements, improve the mixing uniformity of fuel and air, optimize the combustion process, and improve the power performance of the diesel engine; (2) Improve emission performance: Under transient conditions, combined with the ECU transient condition prediction algorithm, the swirl ratio can be adaptively adjusted to effectively improve the deterioration of combustion efficiency and pollutant emission levels caused by the imbalance of oil and gas ratio under transient conditions of diesel engines; (3) Improve thermal efficiency: The optimized oil-gas mixing and combustion process enables more effective use of fuel energy, thereby improving the thermal efficiency of the diesel engine, reducing fuel consumption, and improving the economy of the diesel engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative 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: Figure 1 This is a schematic diagram of a variable swirl ratio combustion system for introducing an external high-pressure gas according to an embodiment of the present application; Figure 2 This is a schematic diagram of a variable swirl ratio combustion system for generating high-speed jets through active combustion in a diesel engine according to Embodiment 1 of the present application; Figure 3 For the embodiments of this application Figure 1 Schematic diagram of the assembly relationship between the independent chamber adapter set, auxiliary fuel injector, and diesel engine cylinder head in the combustion system; Figure 4 This is a schematic diagram of the specific structure of the high-speed jet channel described in the embodiment of the present application; Figure 5 This is a schematic diagram of control unit signal interaction described in an embodiment of the present application.

[0016] Description of reference numerals: 1-cylinder; 2-main combustion chamber; 3-auxiliary injector; 4-adapter set; 5-auxiliary combustion chamber; 6-high-speed jet channel; 7-first jet channel; 8-second jet channel; 9-high-pressure gas tank; 10-control unit; 11-high-pressure common rail; 12-high-pressure oil pump; 13-cylinder head. DETAILED DESCRIPTION

[0017] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0018] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should have the ordinary meanings understood by those with ordinary skills in the field to which the present application belongs. The "first", "second" and similar terms used in the embodiments of the present application do not denote any order, quantity or importance, but are only used to distinguish different components. Words such as "comprising" or "including" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Upper", "lower", "left", "right", etc. are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0019] Please refer to Figure 1 and Figure 2 shown in the figure, this embodiment provides an adaptive variable swirl ratio diesel engine combustion system, which is characterized by including: A swirl ratio adjustment device, which is arranged on cylinder 1. Among them, the swirl ratio adjustment device includes an external source high-pressure gas introduction device and an auxiliary fuel injection device; A diesel engine control unit 10, which controls the external source high-pressure gas introduction device or the auxiliary fuel injection device to act, and the generated high-speed air flow tangentially enters the main combustion chamber 2 of cylinder 1 through the high-speed jet channel 6, so that the high-speed air flow is in the same or opposite direction as the original engine intake swirl, thereby adjusting the in-cylinder swirl ratio.

[0020] Specifically, in this embodiment, according to the high and low load conditions of the diesel engine, high-speed air flow in the same or opposite direction as the original engine intake swirl is introduced to adjust the swirl ratio. The methods for forming the high-speed air flow include introducing external source high-pressure gas, generating high-speed jets through in-cylinder active combustion, etc. The outlet of the high-speed jet channel 6 needs to tangentially enter the combustion chamber, and the swirl ratio is adjusted according to the intake swirl direction.

[0021] Within the combustion duration range, usually within 20deg after top dead center of compression, high-speed air flow is introduced to adjust the in-cylinder swirl ratio. Specifically, when the diesel engine is in a high load condition, the lack of in-cylinder fuel-air mixing energy leads to a slow combustion speed, and when the swirl ratio needs to be increased, high-speed air flow in the same direction as the original engine intake swirl is introduced; when the diesel engine is in a low load condition, the excess mixing energy will increase the proportion of lean mixtures, affecting the combustion efficiency and HC emissions, and when the swirl ratio needs to be decreased, high-speed air flow in the opposite direction to the original engine intake swirl should be introduced at this time.

[0022] Such as Figure 5As shown, under steady-state conditions, according to the fuel injection characteristics at different loads and the swirl ratio characteristics at different speeds, a suitable swirl ratio is calibrated for the entire operating range during the diesel engine design stage. And for different methods of forming high-speed airflows, by adjusting the valve opening time, valve opening duration of the external high-pressure gas, or the injection timing and injection duration of the auxiliary injector 3, the control of the swirl ratio is achieved.

[0023] During the actual operation of the vehicle, the diesel engine electronic control system real-time collects the diesel engine operating condition characteristic information, such as the throttle opening, speed, etc. According to the preset model prediction algorithm (MPC, this algorithm is a mature technology applied in this field, and this application does not improve it, so no further elaboration will be made here), the operating condition prediction and adaptive parameter adjustment are completed. Different from the traditional PID control, the MPC algorithm can achieve global coordination through online optimization and shows significant advantages in the field of engine control, mainly applied to operating condition prediction and transient operating condition control. The control unit 10 judges the change of the diesel engine operating condition, analyzes the mixed energy demand in the transient operating condition, and sends an instruction to the swirl ratio adjustment device to accurately control the introduction direction and intensity of the high-speed airflow, realizing the adaptive adjustment of the swirl ratio.

[0024] Taking an example to illustrate the control logic of the active combustion in the diesel engine to generate a high-speed jet. Taking the transient operating condition of a 10L displacement six-cylinder heavy-duty diesel engine at low speed (1200 rpm) with a constant speed and sudden torque increase as an example, the throttle sensor reading interval is 10 ms. By calculation, the change amount is converted into the change rate per second. When the throttle change rate exceeds 20% / s, the control unit 10 determines based on the data-driven model in the MPC algorithm that the engine enters the working state of sudden torque increase. At this time, the engine will have a mismatch between the intake air increment and the fuel injection increment due to the turbo lag effect, which will further deteriorate the in-cylinder fuel-air mixing process and combustion process. At this time, it is necessary to increase the in-cylinder swirl ratio to promote fuel mixing. The model calculation in the MPC algorithm shows that the air-fuel ratio is lower than the limit value of 0.5 within the next 5 - 10 control cycles. An instruction to increase the opening is sent to the fuel quantity metering unit of the high-pressure fuel pump in advance to increase the diesel pressure to 180 MPa, and an instruction to start injecting fuel at 5 deg. ATDC with an injection pulse width of 500 us is sent to the auxiliary injector 3. The auxiliary injector 3 will inject about 10 mg of fuel inside the pre-chamber. The fuel burns inside the pre-chamber to generate a pressure difference, and then a high-speed jet in the same direction as the swirl is formed inside the main combustion chamber 2, realizing the adaptive enhancement of the in-cylinder swirl ratio.

[0025] In some embodiments, as Figure 3 shown, several independent chamber structures are arranged in the cylinder head area of the cylinder 1. An adapter sleeve 4 is nested inside the independent chamber. An auxiliary combustion chamber 5 is reserved inside the adapter sleeve 4. An auxiliary injector 3 is installed inside the auxiliary combustion chamber. The auxiliary injector 3 is connected to the fuel supply system and the control unit 10; The auxiliary combustion chamber 5 has a multi-stage stepped structure, and its bottom is connected to the main combustion chamber 2 through a high-speed jet channel 6. Among them, the high-speed jet channel 6 includes a first jet channel 7 and a second jet channel 8. The first jet channel 7 is opposite to the intake air swirl of the original engine, and the jet generated by this channel will reduce the swirl ratio. The second jet channel 8 is in the same direction as the intake air swirl of the original engine, and the jet generated by this channel will increase the swirl ratio; The diesel engine control unit 10 controls the auxiliary injector 3 to inject fuel into the auxiliary combustion chamber 5. The fuel starts to burn in the auxiliary combustion chamber 5 and builds pressure. A pressure difference is generated between the auxiliary combustion chamber 5 and the main combustion chamber 2, so that the gas enters the main combustion chamber 2 from the auxiliary combustion chamber 5 in the form of tangential jet along the high-speed jet channel 6, and the jet direction is controlled to be in the same or opposite direction as the intake air swirl of the original engine, thereby adjusting the in-cylinder swirl ratio.

[0026] Specifically, in this embodiment, the high-speed jet realizes the change of the in-cylinder swirl ratio. For the above-mentioned various ways of forming high-speed air flow, the jet channels need to be reasonably arranged. The intake air swirl is mostly tangential intake air swirl. Therefore, the outlet of the high-speed jet channel 6 should be arranged to meet the requirement of the high-speed jet entering the combustion chamber tangentially as much as possible. The jet in the same direction as the actual intake air swirl can increase the swirl ratio, and the jet in the opposite direction to the actual intake air swirl can reduce the swirl ratio.

[0027] This embodiment adopts a two-way swirl ratio adjustment device. Among them, the first is an auxiliary fuel injection device, that is, the method of generating high-speed jet by active combustion in the diesel engine. In this application, within the range of the piston concave pit, an independent chamber structure is arranged in the water jacket space area of the cylinder head. An adapter sleeve 4 is nested in the independent chamber, and an auxiliary combustion chamber 5 is reserved in the adapter sleeve 4. An auxiliary injector 3 is installed in the auxiliary combustion chamber 5. The auxiliary injector 3 can be connected to the fuel supply system of the diesel engine (such as connected to the high-pressure oil pump 12 through the high-pressure common rail pipe 11) or other fuel supply systems.

[0028] Such as Figure 3 and Figure 4 As shown, the auxiliary combustion chamber 5 has a multi-stage stepped structure, and its bottom is connected to the main combustion chamber 2 through a high-speed jet channel 6. Among them, the high-speed jet channel 6 includes a first jet channel 7 and a second jet channel 8. As Figure 3 shown, the first jet channel 7 is opposite to the intake air swirl of the original engine, and the second jet channel 8 is in the same direction as the intake air swirl of the original engine.

[0029] It should be noted that the types of injected fuel are not limited to diesel, but it will increase the complexity of the multi-fuel tank layout. The auxiliary injector 3 injects fuel at an appropriate time, and the combustion process occurs inside the independent chamber and builds high-pressure potential energy. Driven by the pressure difference between the independent chamber and the main combustion chamber 2, a high-speed jet is formed and enters the combustion chamber. The advantage of this layout is that the structure is simple, no external equipment needs to be added, and the jet pressure can be guaranteed.

[0030] In some embodiments, the external high-pressure gas introduction device includes a high-pressure gas tank 9. The high-pressure gas tank 9 is connected to the main combustion chamber 2 of the cylinder 1 through a connecting pipe. Wherein, the outlet direction of the connecting pipe is tangentially arranged in the main combustion chamber 2, and an electronically controlled valve is installed on the connecting pipe to control the injection of the high-pressure gas in the high-pressure gas tank 9 into the main combustion chamber 2; The diesel engine control unit 10 controls the operation of the electronically controlled valve. The high-pressure gas is injected from the high-pressure gas tank 9 into the main combustion chamber 2, and the injection direction of the high-pressure gas is controlled to be the same as or opposite to the original engine intake swirl, thereby adjusting the in-cylinder swirl ratio.

[0031] Specifically, in this embodiment, the second is the external high-pressure gas introduction device, that is, introducing external high-pressure gas. Specifically: a high-pressure gas tank 9 is arranged in the diesel engine intake system, which stores high-pressure nitrogen with a pressure of more than 15 MPa, and a connecting pipe connecting the high-pressure gas tank 9 and the cylinder 1. The outlet direction of the pipe ensures that the high-pressure gas can enter the combustion chamber tangentially, and an electronically controlled valve is installed on the pipe.

[0032] Optionally, by mounting a high-pressure gas tank 9 on the vehicle, the gas type can be selected but is not limited to air, nitrogen, etc. The gas source pressure can be selected according to the actual diesel engine compression ratio and intake system configuration. Generally, a gas source pressure of 15 MPa can meet the use requirements of most commercial diesel locomotives.

[0033] Optionally, the air compressor carried by the engine generates high-pressure air. Generally, the air-assisted braking system carried by commercial vehicles uses a diesel engine to drive an air compressor to compress natural air and store it in the corresponding air storage pipe. By adjusting the opening and closing state of the pipeline valve, this part of the gas can be introduced into the cylinder. However, the pressure of this part of the gas is usually in the range of 0.7 - 1.0 MPa, and the maximum does not exceed 1.2 MPa. Therefore, it is only applicable to naturally aspirated diesel engines with a low compression ratio. In the later stage of the expansion stroke, this part of the air flow is introduced to improve the emissions of the diesel engine.

[0034] For the external high-pressure gas introduction device, the layout of the high-speed jet channel 6 is more flexible than that of the high-speed jet channel 6 provided by the auxiliary fuel injection device. The high-speed jet channel 6 in the same direction as or opposite to the original engine intake swirl can be arranged on the cylinder head 1 of the cylinder 1, or the high-speed jet channel 6 in the same direction as or opposite to the original engine intake swirl can be arranged on the cylinder block. The purpose is to enable the high-pressure gas to be tangentially injected into the main combustion chamber 2.

[0035] Example 1. External high-pressure gas introduction System setup: In the intake system of a diesel engine, a high-pressure gas tank 9 is set up to store high-pressure nitrogen with a pressure above 15 MPa. The high-pressure gas tank 9 is connected to the cylinder 1 through a pipeline, and the outlet direction of the pipeline should ensure that the high-pressure gas can tangentially enter the main combustion chamber 2. An electronically controlled valve is installed on the pipeline to control the injection timing and flow rate of the high-pressure gas.

[0036] Working process: When the electronic control system detects that the diesel engine is in a working condition where the swirl ratio needs to be adjusted, the main control unit controls the opening of the electronically controlled valve, and high-pressure nitrogen is injected from the high-pressure gas tank 9 into the cylinder 1. If it is necessary to increase the swirl ratio, the injection direction of the high-pressure gas is controlled to be the same as the original engine intake swirl; if it is necessary to decrease the swirl ratio, the injection direction is controlled to be opposite to the original engine intake swirl. By precisely controlling the injection parameters of the high-pressure gas, precise adjustment of the swirl ratio is achieved.

[0037] Active combustion in the diesel engine generates a high-speed jet Structural design: An independent chamber structure is arranged in the water jacket space of the cylinder 1 head. The independent chamber is connected to the main combustion chamber 2 through a high-speed jet channel 6, ensuring that the high-speed jet can tangentially enter the main combustion chamber 2 to regulate the swirl ratio. An auxiliary injector 3 is installed on the top of the chamber. The auxiliary injector 3 can be connected to the fuel supply system of the diesel engine or other fuel supply systems.

[0038] Working process: When the diesel engine is running, the diesel engine electronic control unit judges the change of the diesel engine working condition based on the preset model prediction algorithm according to the real-time collected diesel engine working condition characteristic information, such as throttle opening, engine speed, etc. For example, when the change rate of the throttle opening is greater than 20% / second, it is judged that the diesel engine enters a sudden load condition, that is, a condition of lack of mixed energy, and it is necessary to increase the in-cylinder swirl ratio. The electronic control unit controls the auxiliary injector 3 to inject fuel into the independent chamber. The fuel starts to burn and build pressure in the independent chamber, forming a pressure difference with the main combustion chamber 2, so that the gas enters the main combustion chamber 2 in the form of a tangential jet from the chamber through the channel, thereby realizing the adjustment of the swirl ratio. For example, when it is necessary to increase the swirl ratio, the channel is designed so that the jet direction is the same as the original engine intake swirl; when it is necessary to decrease the swirl ratio, the jet direction is opposite to the original engine intake swirl. At the same time, according to different working conditions, the electronic control system precisely controls the fuel injection volume and injection timing of the auxiliary injector 3 to achieve precise adjustment of the swirl ratio.

[0039] The combustion system described in this embodiment realizes flexible adjustment of the intake swirl ratio under all working conditions, accurately controls the in-cylinder mixed energy according to the working condition requirements, improves the mixing uniformity of fuel and air, optimizes the combustion process, and enhances the power performance and economy of the diesel engine.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present invention, and they should all be covered by the scope of the claims and the description of the present invention.

[0041] Embodiments of the present application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of the present application shall be included within the protection scope of the present application.

Claims

1. An adaptive variable swirl ratio diesel engine combustion system, characterized in that: include: A swirl ratio adjusting device, wherein the swirl ratio adjusting device is arranged on the cylinder, wherein the swirl ratio adjusting device comprises an external high-pressure gas introducing device and an auxiliary oil injection device; A diesel engine control unit controls the operation of the external high-pressure gas introduction device or the auxiliary fuel injection device, and the generated high-speed airflow enters the main combustion chamber of the cylinder tangentially through the high-speed jet channel, so that the high-speed airflow is in the same direction or in the opposite direction as the original engine intake vortex, thereby adjusting the vortex ratio in the cylinder.

2. The adaptive variable swirl ratio diesel engine combustion system according to claim 1, characterized in that: The cylinder head area of ​​the cylinder is arranged with a plurality of independent chamber structures, wherein an adaptor set is nested in the independent chamber, an auxiliary combustion chamber is reserved in the adaptor set, an auxiliary fuel injector is installed in the auxiliary combustion chamber, and the auxiliary fuel injector is connected to the fuel supply system and the control unit; The auxiliary combustion chamber is communicated with the main combustion chamber.

3. The adaptive variable swirl ratio diesel engine combustion system according to claim 2, characterized in that: The auxiliary combustion chamber is in a multi-step structure, and the bottom of the auxiliary combustion chamber is connected with the main combustion chamber through a high-speed jet channel.

4. The adaptive variable swirl ratio diesel engine combustion system according to claim 3, characterized in that: in, The high-speed jet channel includes a first jet channel and a second jet channel. The first jet channel is in the opposite direction to the original engine intake vortex, and the second jet channel is in the same direction as the original engine intake vortex.

5. The adaptive variable swirl ratio diesel engine combustion system according to claim 2, characterized in that: The diesel engine control unit controls the auxiliary injector to spray fuel into the auxiliary combustion chamber. The fuel starts to burn and build up pressure in the auxiliary combustion chamber. A pressure difference is generated between the auxiliary combustion chamber and the main combustion chamber, so that the gas enters the main combustion chamber from the auxiliary combustion chamber along the high-speed jet channel in the form of a tangential jet. The jet direction is controlled to be in the same direction or opposite direction as the original engine intake vortex, thereby adjusting the swirl ratio in the cylinder.

6. The adaptive variable swirl ratio diesel engine combustion system according to claim 1, characterized in that: The external high-pressure gas introduction device includes a high-pressure gas tank, which is connected to the main combustion chamber of the cylinder through a connecting pipe, wherein the outlet direction of the connecting pipe is tangentially arranged in the main combustion chamber.

7. The adaptive variable swirl ratio diesel engine combustion system according to claim 6, characterized in that: The connecting pipeline is provided with an electric control valve to control the high pressure gas in the high pressure gas tank to be sprayed into the main combustion chamber.

8. The adaptive variable swirl ratio diesel engine combustion system according to claim 7, characterized in that: The diesel engine control unit controls the action of the electronically controlled valve, and the high-pressure gas is ejected from the high-pressure gas tank into the main combustion chamber, and the high-pressure gas injection direction is controlled to be in the same direction or in the opposite direction to the original engine intake vortex, thereby adjusting the vortex ratio in the cylinder.

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