A partitioned combustion structure for a dual-fuel internal combustion engine

Abstract

The present invention discloses a partitioned combustion structure of a dual-fuel internal combustion engine, comprising an injector and a combustion chamber, wherein the injector is mounted on the upper portion of the combustion chamber, and the lower end of the injector is provided with a nozzle component placed at the top end of the combustion chamber, wherein the nozzle component is mainly composed of a needle valve, an air valve, and a valve body, wherein the needle valve is placed in the air valve, and a diesel inlet channel and a diesel pressure chamber are provided between the needle valve and the air valve, and a natural gas inlet channel and a natural gas pressure chamber are provided between the valve body and the air valve. The present invention relates to an internal combustion engine combustion mode, and in particular to a partitioned combustion structure of a dual-fuel internal combustion engine, belonging to the technical field of internal combustion engines. The present invention ensures the normal ignition and combustion of a dual-fuel internal combustion engine and facilitates combustion control; the present invention simplifies the structural design of the nozzle component, optimizes the processing technology, reduces the difficulty of component processing, improves the product qualification rate, and reduces production costs; the partitioned combustion method in the present invention enables the injector to be designed in an overall compact manner and optimizes the product structure.

Description

Technical Field

[0001] The present invention relates to a combustion mode of an internal combustion engine, in particular to a partitioned combustion structure of a dual-fuel internal combustion engine, and belongs to the technical field of internal combustion engines. Background Art

[0002] With the gradual escalation of emission standards, traditional internal combustion engines fueled by gasoline and diesel are increasingly unable to meet the requirements of future combustion technologies. With the adjustment of China's energy structure, the available fuels for internal combustion engines are becoming increasingly diverse, including natural gas, liquefied petroleum gas (LPG), methanol, and many other clean fuels. Internal combustion engines fueled by diesel use compression ignition, offering advantages such as high compression ratios, high thermal efficiency, and high torque output. Clean fuels such as natural gas, liquefied petroleum gas (LPG), and methanol are not easily compression-ignited. To fully leverage the advantages of diesel and clean fuels, a number of dual-fuel direct injection technologies have emerged. These technologies involve first injecting a certain amount of diesel into the internal combustion engine's combustion chamber, followed by the addition of clean fuel. Upon entering the combustion chamber, the diesel fuel spontaneously ignites, forming a self-ignition zone. The subsequent fuel, if injected into the self-ignition zone, will ignite, thus achieving combustion and power generation in the internal combustion engine.

[0003] The amount of diesel injected into the combustion chamber is relatively small, primarily serving as a ignition trigger. However, the varying vortex strength within the combustion chamber of an internal combustion engine and the varying relative angles between the diesel and clean fuel nozzles can cause variations in the autoignition zone. When the diesel injection trajectory overlaps significantly with the subsequent clean fuel injection trajectory, the subsequent fuel injection can lower the temperature in the autoignition zone, potentially causing the autoignited diesel to blow out. This can lead to delayed or even non-ignition of the subsequent fuel, resulting in engine failure. Current dual-fuel internal combustion engine technology employs a fixed relative angle between the diesel and clean fuel nozzles, ensuring they are not aligned on the same injection trajectory. This prevents blowout of the compression-ignited diesel. However, the overall design of an internal combustion engine is very compact, leaving little space for injector installation. This fixed diesel and clean fuel nozzle design reduces the injector nozzle wall thickness, making component fabrication difficult and reducing reliability. Furthermore, the injector's overall size is relatively large, preventing a compact design and creating significant challenges for engine installation.

[0004] In order to avoid the compression ignition of diesel being blown out, reduce the design and processing difficulty of components, and reasonably and compactly design the injector structure, a dual-fuel internal combustion engine partitioned combustion method is needed to solve this problem. Summary of the Invention

[0005] The object of the present invention is to provide a partitioned combustion structure of a dual-fuel internal combustion engine to solve the problems raised in the above background technology.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a dual-fuel internal combustion engine zone combustion structure, comprising an injector and a combustion chamber, the injector being mounted on the upper portion of the combustion chamber, the lower end of the injector being provided with a nozzle assembly positioned at the top end of the combustion chamber, the nozzle assembly being mainly composed of a needle valve, an air valve, and a valve body, the needle valve being positioned within the air valve, a diesel inlet passage and a diesel pressure chamber being positioned between the needle valve and the air valve, the diesel pressure chamber being positioned at the lower end of the needle valve, a needle valve sealing surface being positioned at the lower end of the diesel inlet passage being positioned between the needle valve and the air valve, the air valve being positioned within the valve body, a natural gas inlet passage being positioned between the air valve and the valve body, an air valve sealing surface being positioned at the lower end of the natural gas inlet passage being positioned between the air valve and the valve body, a natural gas pressure chamber being positioned below the air valve sealing surface being positioned between the air valve and the valve body, the lower end of the air valve being movably plugged into the lower end of the valve body, a plurality of oil injection holes being formed at the lower end of the air valve, and a plurality of air injection holes being formed at the lower end of the valve body, which are in communication with the diesel pressure chamber.

[0007] As a preferred technical solution of the present invention, the air jets spray air beams, the oil jets spray oil beams, and a greatest common divisor exists between the total number of the oil jets and the total number of the air jets. The combustion chamber is divided into a corresponding number of combustion zones based on the value of the greatest common divisor. In each combustion zone, the air beams and oil beams have the same number, and the total number of air beams and the total number of oil beams cannot be divided evenly.

[0008] As a preferred technical solution of the present invention, the air beam injection area cannot completely cover the oil beam injection area, and the oil beam can self-ignite in the combustion chamber.

[0009] As a preferred technical solution of the present invention, the air injection holes and the oil injection holes are arranged at a certain angle to the center of the nozzle component, and are respectively distributed in a ring shape at the valve body and the air valve head.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] The present invention ensures normal ignition and combustion of a dual-fuel internal combustion engine and facilitates combustion control;

[0012] The present invention simplifies the structural design of the nozzle components, optimizes the processing technology, reduces the difficulty of component processing, improves the product qualification rate, and reduces production costs;

[0013] The zoned combustion method of the present invention enables the injector to be designed in an overall compact manner and optimizes the product structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Attachment Figure 1 Schematic diagram of the nozzle component structure;

[0015] Attachment Figure 2This is a schematic diagram of the distribution of one zone in the zone combustion method;

[0016] Attachment Figure 3 This is a schematic diagram of the two-zone distribution of the zone combustion method;

[0017] Attachment Figure 4 This is a schematic diagram of the three-zone distribution of the zoned combustion method;

[0018] Attachment Figure 5 This is a schematic diagram of the four-zone distribution of the zoned combustion method;

[0019] Attachment Figure 6 This is a schematic diagram of the five-zone distribution of the zoned combustion method;

[0020] Attachment Figure 7 This is a schematic diagram of the six-zone distribution of the zoned combustion method;

[0021] Attachment Figure 8 This is a schematic diagram of the seven-zone distribution of the zoned combustion method;

[0022] Attachment Figure 9 This is a schematic diagram of the eight-zone distribution of the zone combustion method;

[0023] Attachment Figure 10 This is a schematic diagram of the nine-zone distribution of the zoned combustion method.

[0024] In the figure: 01, needle valve, 02, air valve, 03, valve body, 04, natural gas inlet channel, 05, diesel inlet channel, 06, air valve sealing surface, 07, needle valve sealing surface, 08, natural gas pressure chamber, 09, injection hole, 10, diesel pressure chamber, 11, fuel injection hole, 12, nozzle component, 13, air beam, 14, fuel beam, 15, combustion chamber. DETAILED DESCRIPTION

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] See also Figure 1-10 ,

[0027] In the present invention, the pilot fuel of the dual-fuel internal combustion engine is diesel, and the clean fuel for main combustion can be natural gas, liquefied petroleum gas, methane gas, ethane gas, methanol and other forms of fuel. For the sake of convenience, the clean fuel in the following content is represented by natural gas.

[0028] The present invention provides a dual-fuel internal combustion engine partition combustion structure, including an injector and a combustion chamber 15, the injector is installed at the upper part of the combustion chamber 15, the lower end of the injector is provided with a nozzle component 12 placed at the top end of the combustion chamber 15, the nozzle component 12 is mainly composed of a needle valve 01, an air valve 02 and a valve body 03, the needle valve 01 is placed in the air valve 02, and a diesel inlet channel 05 and a diesel pressure chamber 10 are provided between the needle valve 01 and the air valve 02, the diesel pressure chamber 10 is placed at the lower end of the needle valve 01, a needle valve sealing surface 07 is provided between the needle valve 01 and the air valve 02, the air valve 02 is placed in the valve body 03, and a There is a natural gas inlet channel 04, and a valve sealing surface 06 is provided between the gas valve 02 and the valve body 03, which is located at the lower end of the natural gas inlet channel 04. A natural gas pressure chamber 08 is provided between the gas valve 02 and the valve body 03, which is located at the lower end of the gas valve sealing surface 6. The lower end of the gas valve 02 is movably inserted into the lower end of the valve body 03. The lower end of the gas valve 02 is provided with a plurality of oil injection holes 11 that are connected to the diesel pressure chamber 10, and the lower end of the valve body 03 is provided with a plurality of jet holes 09 that are connected to the natural gas pressure chamber 08. The jet holes 09 and the jet holes 11 are both inclined and distributed in a ring shape at the ends of the valve body 03 and the gas valve 02, respectively. The jet hole 09 is located above the jet hole 11.

[0029] Among them, the jet hole 09 sprays an air beam 13, and the oil jet hole 11 sprays an oil beam 14. There is a greatest common divisor between the total number of oil jet holes 11 and the total number of jet holes 09. The combustion chamber 15 is divided into a corresponding number of combustion zones according to the value of the greatest common divisor. In each combustion zone, the air beam 13 and the oil beam 14 have the same number, and the total number of air beams 13 and the total number of oil beams 14 cannot be divided evenly. The injection area of the air beam 13 cannot completely cover the injection area of the oil beam 14, and the oil beam 14 can spontaneously combust in the combustion chamber 15.

[0030] During use, the injector controls the needle valve 01 to move upward. When the needle valve 01 detaches from the needle valve sealing surface 07, the needle valve 01 opens, the diesel inlet channel 05 communicates with the diesel pressure chamber 10, and the diesel passes through the injection hole 11 and is sprayed into the combustion chamber 15, forming an oil beam 14 during injection. The injector controls the gas valve 02 to move upward. When the gas valve 02 detaches from the gas valve sealing surface 06, the gas valve 02 opens, the natural gas inlet channel 04 communicates with the natural gas pressure chamber 08, and the natural gas passes through the injection hole 09 and is sprayed into the combustion chamber 15, forming a gas beam 13 during injection.

[0031] When the needle valve 01 is opened, the oil beam 14 injected into the combustion chamber 15 will vaporize and self-ignite in the combustion chamber 15, forming a self-ignition area. Then the air valve 02 is opened, and the air beam 13 injected into the combustion chamber 15 will start to burn under the ignition of the oil beam 14 in the self-ignition area, thereby realizing the combustion work of the engine. The fuel proportion of the oil beam 14 injected into the combustion chamber 15 is relatively small, and the fuel proportion of the air beam 13 injected into the combustion chamber 15 is relatively large. When the air beam 13 is injected into the combustion chamber 15 by the injector, the air pressure changes from a high-pressure state to a low-pressure state and absorbs heat. If the air beam 13 area covers most or even all of the oil beam 14 area, the gas expansion and heat absorption will lower the temperature of the self-ignition area of the oil beam 14, so that neither the oil beam 14 nor the air beam 13 can reach the ignition temperature. , the engine cannot ignite to burn and produce work; in the present invention, a zoned combustion method is adopted, that is, there is a greatest common divisor between the number of fuel injection holes 11 and the number of air jet holes 09. According to the value of the greatest common divisor, the combustion chamber 15 is divided into a corresponding number of combustion zones, and in each combustion zone, there are the same number of oil beams 14 and the same number of air beams 13, and the total number of oil beams 14 and the total number of air beams 13 cannot be divided evenly. In the nozzle component 12 of the injector, there is no need to form a fixed angle between the needle valve 01 and the air valve 02. By designing the number of fuel injection holes 11 and air jet holes 09, the air beam 13 area is controlled so that it cannot completely cover the oil beam 14 area, ensuring that the diesel can self-ignite normally, thereby igniting the combustion of the entire fuel, so that the engine can burn normally and produce work.

[0032] The following describes different partitioning examples:

[0033] In the first embodiment, the greatest common divisor of the number of the fuel injection holes 11 and the number of the injection holes 09 is 1, and the combustion chamber 15 is divided into one zone. The zone combustion method is shown in the attached diagram. Figure 2 In the schematic diagram, the number of fuel injection holes 11 is 9, and the number of air jet holes 09 is 13. In each position relationship between the needle valve 01 and the air valve 02, self-ignition and ignition of the corresponding oil beam 14 area can be achieved. The one-zone combustion method also includes other combinations in which the greatest common divisor of the number of fuel injection holes 11 and the number of air jet holes 09 is 1.

[0034] In the second embodiment, the greatest common divisor of the number of the fuel injection holes 11 and the number of the injection holes 09 is 2, and the combustion chamber 15 is divided into two zones. The two-zone distribution diagram of the zone combustion method is shown in the attached figure. Figure 3 In the schematic diagram, the number of fuel injection holes 11 is 10, and the number of air jet holes 09 is 14. In each partition, the number of fuel injection holes 11 is 5, and the number of air jet holes 09 is 7. In each position relationship between the needle valve 01 and the air valve 02, self-ignition and ignition of the corresponding oil beam 14 areas can be achieved. The two-zone combustion method also includes other combinations in which the greatest common divisor of the number of fuel injection holes 11 and the number of air jet holes 09 is 2.

[0035] Example 3: The greatest common divisor of the number of the fuel injection holes 11 and the number of the injection holes 09 is 3, so the combustion chamber 15 is divided into three zones. The three-zone distribution diagram of the zoned combustion method is shown in the attached figure. Figure 4 In the schematic diagram, the number of fuel injection holes 11 is 9, and the number of air jet holes 09 is 12. In each partition, the number of fuel injection holes 11 is 3, and the number of air jet holes 09 is 4. In each position relationship between the needle valve 01 and the air valve 02, self-ignition and ignition of the corresponding oil beam 14 area can be achieved. The three-zone combustion method also includes other combinations in which the greatest common divisor of the number of fuel injection holes 11 and the number of air jet holes 09 is 3.

[0036] Example 4: The greatest common divisor of the number of the fuel injection holes 11 and the number of the injection holes 09 is 4, so the combustion chamber 15 is divided into four zones. The four-zone distribution diagram of the zone combustion method is shown in the attached figure. Figure 5 In the schematic diagram, the number of fuel injection holes 11 is 8, and the number of air jet holes 09 is 12. In each partition, the number of fuel injection holes 11 is 2, and the number of air jet holes 09 is 3. In each position relationship between the needle valve 01 and the air valve 02, self-ignition and ignition of the corresponding oil beam 14 area can be achieved. The four-zone combustion method also includes other combinations in which the greatest common divisor of the number of fuel injection holes 11 and the number of air jet holes 09 is 4.

[0037] Example 5: The greatest common divisor of the number of the fuel injection holes 11 and the number of the injection holes 09 is 5, so the combustion chamber 15 is divided into five zones. The five-zone distribution diagram of the zone combustion method is shown in the attached figure. Figure 6 In the schematic diagram, the number of fuel injection holes 11 is 10, and the number of air jet holes 09 is 15. In each partition, the number of fuel injection holes 11 is 2, and the number of air jet holes 09 is 3. In each position relationship between the needle valve 01 and the air valve 02, self-ignition and ignition of the corresponding oil beam 14 area can be achieved. The five-zone combustion method also includes other combinations in which the greatest common divisor of the number of fuel injection holes 11 and the number of air jet holes 09 is 5.

[0038] Example 6: The greatest common divisor of the number of the fuel injection holes 11 and the number of the injection holes 09 is 6, so the combustion chamber 15 is divided into six zones. The six-zone distribution diagram of the zone combustion method is shown in the attached figure. Figure 7 In the schematic diagram, the number of fuel injection holes 11 is 12, and the number of air jet holes 09 is 18. In each partition, the number of fuel injection holes 11 is 2, and the number of air jet holes 09 is 3. In each position relationship between the needle valve 01 and the air valve 02, self-ignition and ignition of the corresponding oil beam 14 area can be achieved. The six-zone combustion method also includes other combinations in which the greatest common divisor of the number of fuel injection holes 11 and the number of air jet holes 09 is 6.

[0039] Example 7: The greatest common divisor of the number of the fuel injection holes 11 and the number of the injection holes 09 is 7, so the combustion chamber 15 is divided into seven zones. The seven-zone distribution diagram of the zone combustion method is shown in the attached figure. Figure 8In the schematic diagram, the number of fuel injection holes 11 is 14, and the number of air jet holes 09 is 21. In each partition, the number of fuel injection holes 11 is 2, and the number of air jet holes 09 is 3. In each position relationship between the needle valve 01 and the air valve 02, self-ignition and ignition of the corresponding oil beam 14 areas can be achieved. The seven-zone combustion method also includes other combinations in which the greatest common divisor of the number of fuel injection holes 11 and the number of air jet holes 09 is 7.

[0040] Example 8: The greatest common divisor of the number of the fuel injection holes 11 and the number of the injection holes 09 is 8, so the combustion chamber 15 is divided into eight zones. The eight-zone distribution diagram of the zone combustion method is shown in the attached figure. Figure 9 In the schematic diagram, the number of fuel injection holes 11 is 16, and the number of air jet holes 09 is 24. In each partition, the number of fuel injection holes 11 is 2, and the number of air jet holes 09 is 3. In each position relationship between the needle valve 01 and the air valve 02, self-ignition and ignition of the corresponding oil beam 14 area can be achieved. The eight-zone combustion method also includes other combinations in which the greatest common divisor of the number of fuel injection holes 11 and the number of air jet holes 09 is 8.

[0041] Example 9: The greatest common divisor of the number of the fuel injection holes 11 and the number of the injection holes 09 is 9, so the combustion chamber 15 is divided into nine zones. The nine-zone distribution diagram of the zone combustion method is shown in the attached figure. Figure 8 In the schematic diagram, the number of fuel injection holes 11 is 18, and the number of air jet holes 09 is 27. In each partition, the number of fuel injection holes 11 is 2, and the number of air jet holes 09 is 3. In each position relationship between the needle valve 01 and the air valve 02, spontaneous combustion and ignition of the corresponding oil beam 14 area can be achieved. The nine-zone combustion method also includes other combinations in which the greatest common divisor of the number of fuel injection holes 11 and the number of air jet holes 09 is 9.

[0042] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A dual-fuel internal combustion engine partition combustion structure, comprising an injector and a combustion chamber (15), characterized in that: The injector is mounted on the upper portion of the combustion chamber (15). The lower end of the injector is provided with a nozzle component (12) disposed at the top end of the combustion chamber (15). The nozzle component (12) is mainly composed of a needle valve (01), an air valve (02) and a valve body (03). The needle valve (01) is disposed in the air valve (02). A diesel inlet passage (05) and a diesel pressure chamber (10) are disposed between the needle valve (01) and the air valve (02). The diesel pressure chamber (10) is disposed at the lower end of the needle valve (01). A needle valve sealing surface (07) disposed at the lower end of the diesel inlet passage (05) is disposed between the needle valve (01) and the air valve (02). The air valve (02) is disposed in the valve body (03). A natural gas inlet passage (04) is provided between the gas valve (02) and the valve body (03), a gas valve sealing surface (06) is provided between the gas valve (02) and the valve body (03) and is located at the lower end of the natural gas inlet passage (04), a natural gas pressure chamber (08) is provided between the gas valve (02) and the valve body (03) and is located at the lower end of the gas valve sealing surface (6), the lower end of the gas valve (02) is movably connected to the lower end of the valve body (03), a plurality of oil injection holes (11) are provided at the lower end of the gas valve (02) and are in communication with the diesel pressure chamber (10), and a plurality of injection holes (09) are provided at the lower end of the valve body (03); There is a greatest common divisor between the total number of the fuel injection holes (11) and the total number of the injection holes (09), and the combustion chamber (15) is divided into a plurality of combustion zones according to the value of the greatest common divisor, and the number of the combustion zones is the same as the greatest common divisor; in each different combustion zone, the number of the air beams (13) is the same, and the number of the oil beams (14) is the same; the total number of the air beams (13) and the total number of the oil beams (14) in all combustion zones cannot be divided evenly; The injection area of the air beam (13) cannot completely cover the injection area of the oil beam (14), and the oil beam (14) can spontaneously combust in the combustion chamber (15); The air injection hole (09) and the oil injection hole (11) are arranged at a certain angle to the center of the nozzle component (12), and are respectively distributed in a ring shape at the valve body (03) and the head of the air valve (02).

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