Multi-layer multi-swirl combustion system, engine and vehicle

Abstract

The invention discloses a multi-layer multi-swirl combustion system, an engine and a vehicle, the multi-layer multi-swirl combustion system comprises a combustion chamber and a hot EGR assembly, the combustion chamber comprises combustion sub-chambers which are arranged in a mirror image mode, each combustion sub-chamber is provided with a plurality of swirl areas and a plurality of collision areas, every two adjacent swirl areas are connected through the corresponding collision area, and each collision area is connected with the corresponding combustion sub-chamber. The surface of the collision area is higher than the surface of the entrainment area; the hot EGR assembly comprises an EGR pipeline, and the EGR pipeline is connected with the exhaust end of the combustion chamber so that part of waste gas generated by the combustion chamber can be fed into an intake manifold. The technical problems that in the prior art, due to the fact that a cold EGR system is adopted, the cost is high, and the heat efficiency of an engine is possibly affected are solved through the multiple rolling flow areas, the multiple collision areas and the hot EGR assembly. And the technical problems of high particle emission and high engine oil dilution risk caused by the fact that an existing combustion chamber cannot guarantee the top oil-gas mixing quality are solved.

Description

Technical Field

[0001] The invention relates to the technical field of engines, in particular to a multi-layer multi-swirling combustion system and an engine vehicle. Background Art

[0002] The fuel crushing and oil-gas mixing process of modern diesel engines directly affect the combustion performance and emission characteristics. Therefore, making the fuel more widely distributed in the combustion chamber space, increasing the mixing speed with air, and reducing the extremely rich and lean areas of fuel in the combustion chamber can significantly improve the power, economy and emission performance of the diesel engine. With the development of automobile technology, higher requirements are put forward for engine performance and emissions, and the design of the combustion system is the key to improving fuel consumption and bare-machine emissions. At present, most of the National VI engines adopt the cold EGR technology route (EGR system is Exhaust Gas Recirculation in English, and is translated into Chinese as exhaust gas recirculation system, which is a major technology for reducing engine emissions). Through the EGR pipeline, the exhaust gas is introduced into the intake manifold according to the required amount and mixed with fresh air before entering the cylinder, so as to effectively control the bare-machine emission of nitrogen oxides. Although the cold EGR system can greatly reduce the emission of nitrogen oxides, it requires the addition of an EGR cooler and related pipelines, which makes the combustion system structure complicated and increases the cost; at the same time, the oxygen content of the cooled exhaust gas is lower, which may affect the thermal efficiency of the engine.

[0003] On the other hand, most existing combustion system designs only consider accelerating the mixing rate in the cylinder and improving the combustion process. The combustion chamber pits are mostly traditional constricted or straight-mouthed rotating body structures, with the throat close to the upper part of the combustion chamber, generating a single vortex inside the combustion chamber, and promoting oil-gas mixing through ultra-high injection pressure and combustion chamber structure matching, thereby achieving efficient and clean combustion, improving fuel economy and particulate emissions. Although this traditional combustion chamber design can ensure the oil-gas mixing quality inside the combustion chamber, it cannot guarantee the oil-gas mixing quality outside the top of the combustion chamber. The particulate emissions are high and the risk of oil dilution is high. At the same time, the cost and reliability risks of the ultra-high pressure injection system are also high.

[0004] In summary, how to improve the formation and distribution of the mixture in the cylinder under the conditions of hot EGR system and lower injection pressure has become a technical problem that needs to be solved urgently in this field. Summary of the invention

[0005] In view of this, the present invention provides a multi-layer and multi-swirling combustion system, an engine and a vehicle, so as to solve the technical problems of high cost and possible influence on thermal efficiency of the engine caused by the cold EGR system in the prior art, and the technical problems of high particle emission and high oil dilution risk caused by the inability of the existing combustion chamber to ensure the quality of the top oil-gas mixture.

[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a multi-layer multi-volute combustion system, comprising: A combustion chamber, comprising a combustion chamber arranged in a mirror image, wherein the combustion chamber is formed with a plurality of vortex areas and a plurality of collision areas, each adjacent two vortex areas are connected by the collision area, and the surface of the collision area is higher than the surface of the vortex area; The hot EGR component comprises an EGR pipe, wherein the EGR pipe is connected to the exhaust end of the combustion chamber to deliver part of the exhaust gas generated by the combustion chamber into the intake manifold.

[0007] In some embodiments, a central boss is formed inside the combustion chamber, the axial symmetry center of the central boss coincides with the axial center of the piston of the combustion chamber, and the axial symmetry center of the central boss divides the combustion chamber into two combustion chambers arranged in a mirrored manner.

[0008] In some embodiments, the combustion chamber includes a first vortex zone, a first collision zone, a second vortex zone, a second collision zone and a third vortex zone. The first vortex zone, the first collision zone, the second vortex zone, the second collision zone and the third vortex zone are arranged in sequence from the axial symmetry center of the central boss toward the throat of the combustion chamber.

[0009] In some embodiments, the arc surface of the first collision zone is higher than the arc surfaces of the first and second swirl zones.

[0010] In some embodiments, the arc surface of the second collision zone is higher than the arc surfaces of the second and third swirl zones.

[0011] In some embodiments, the arc length of the first collision area is greater than the arc length of the second collision area.

[0012] In some embodiments, the combustion chamber further includes a narrow gap area, and the narrow gap area is distributed between the third vortex area and the throat of the combustion chamber.

[0013] In some embodiments, the hot EGR component further includes a solenoid valve, a flow meter and a pressure sensor, wherein the solenoid valve is used to control the switch of the EGR pipe, and the flow meter and the pressure sensor are used to control the flow and pressure of the gas in the EGR pipe respectively.

[0014] In a second aspect, the present invention further provides an engine, which includes the multi-layer and multi-swirling combustion system provided by the above technical solution of the present invention.

[0015] In a third aspect, the present invention also provides a vehicle, comprising the engine provided by the above technical solution of the present invention.

[0016] Compared with the prior art, the present invention provides a multi-layer and multi-swirling combustion system, an engine and a vehicle. By adopting a hot EGR component instead of a cold EGR system, there is no need to add additional components such as an EGR cooler, so the structure of the combustion system is simplified, thereby reducing costs, and the oxygen content in the exhaust gas is increased, thereby improving the thermal efficiency of the engine. On the other hand, under the conditions of a hot EGR component and a low injection pressure, the present invention designs multiple swirling zones and multiple collision zones in the combustion chamber so that the oil and gas can be fully mixed under multiple collisions and swirling, thereby making the oil and gas reasonably matched, which can improve the formation and distribution of the mixed gas in the cylinder, ensure that the combustion process is fast and sufficient, prevent oil dilution, reduce carbon smoke emissions, and ensure that the engine has a higher thermal efficiency and lower fuel consumption and emission levels. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a partial structural schematic diagram of the combustion chamber of the present invention; Figure 2 is a mixed gas flow diagram in a partial structure of the combustion chamber of the present invention; Figure 3 It is a diagram of the oil-gas mixture state in the existing combustion chamber cylinder simulated by computer software; Figure 4 It is a diagram of the oil-gas mixing state in the combustion chamber cylinder of the present invention simulated by computer software.

[0018] The following are the descriptions of the reference numerals: 100. Combustion chamber, 110. Combustion subchamber, 111. First vortex zone, 112. First collision zone, 113. Second vortex zone, 114. Second collision zone, 115. Third vortex zone, 116. Narrow gap zone, 120. Center boss. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0020] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0021] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0022] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be directly connected, detachably connected, or integrally connected; it can be mechanically connected or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be internal communication between two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0024] At present, the combustion system used in diesel engines adopts a cold EGR system on the one hand. Although it can greatly reduce the emission of nitrogen oxides, it requires the addition of an EGR cooler and related measuring instruments and pipelines, which makes the system structure complex and increases the cost; on the other hand, the existing combustion chambers are mostly traditional constricted or straight-mouthed rotary structures, which only produce a single vortex inside the combustion chamber and require ultra-high injection pressure to promote oil-gas mixing. The ultra-high injection system has high costs and risks, and cannot guarantee the oil-gas mixing quality at the top periphery of the combustion chamber. In response to the above technical problems, the present invention provides a multi-layer multi-vortex combustion system, an engine and a vehicle, which can reasonably match the oil and gas both inside and outside the combustion chamber under the conditions of a hot EGR system and low injection pressure, ensuring a fast and sufficient combustion process, so that the engine has higher thermal efficiency and lower fuel consumption and emission levels.

[0025] See also Figure 1 As shown, the present invention provides a multi-layer multi-swirl combustion system, including a combustion chamber 100 and a hot EGR component, wherein the attached Figure 1 A schematic diagram of a combustion chamber 100 is shown with highlighted features, with the hot EGR assembly not shown. Figure 1 As shown in Figure 1 As shown, the combustion chamber 100 includes two combustion chambers 110 arranged in a mirror-like manner, and the combustion chamber 110 forms a plurality of vortex areas and a plurality of collision areas, and each adjacent two vortex areas are connected by the collision area, and the surface of the collision area is higher than the surface of the vortex area; the hot EGR component includes an EGR pipe, and the EGR pipe is connected to the exhaust end of the combustion chamber 100 to send part of the exhaust gas generated by the combustion chamber 100 into the intake manifold to mix with fresh air and then recirculate it to the combustion chamber 100.

[0026] On the one hand, the above-mentioned technical scheme of the present invention adopts a hot EGR component to replace the cold EGR system. Since there is no need to add additional components such as EGR cooler, the structure of the combustion system is simplified, thereby reducing the cost, and the oxygen content in the exhaust gas is increased, thereby improving the thermal efficiency of the engine; on the other hand, in order to avoid the high cost and high risk brought by the ultra-high pressure injection system, the present invention uses a low injection pressure instead. Therefore, in order to cooperate with the hot EGR component and the low injection pressure conditions, the present invention also makes improvements in the structure of the combustion chamber 100, that is, by designing multiple vortex zones and multiple collision zones in the combustion chamber 100, the oil and gas can be fully mixed under multiple collisions and vortices, so that the oil and gas are reasonably matched, which can improve the formation and distribution of the mixed gas in the cylinder, ensure that the combustion process is fast and sufficient, prevent oil dilution, reduce carbon smoke emissions, and ensure that the engine has a higher thermal efficiency and lower fuel consumption and emission levels.

[0027] In one embodiment, if Figure 1As shown, a central boss 120 is formed inside the combustion chamber 100, the axial symmetry center of the central boss 120 coincides with the axial center of the piston of the combustion chamber 100, and the axial symmetry center of the central boss 120 divides the combustion chamber 100 into two combustion chambers 110 that are arranged in a mirrored manner.

[0028] In one embodiment, the combustion chamber 110 includes a first swirl zone 111, a first collision zone 112, a second swirl zone 113, a second collision zone 114 and a third swirl zone 115. The first swirl zone 111, the first collision zone 112, the second swirl zone 113, the second collision zone 114 and the third swirl zone 115 are arranged in sequence from the axial symmetry center of the central boss 120 toward the throat of the combustion chamber 100.

[0029] It is understandable that, in actual use, the collision zone is not limited to only the first collision zone 112 and the second collision zone 114, and the number of collision zones can be adjusted according to actual needs, that is, the formed vortex zone is not limited to only the first vortex zone 111, the second vortex zone 113 and the third vortex zone 115.

[0030] It should be noted that the key point of the present invention is to prevent the fuel from rushing into the narrow gap area 116. Therefore, the swirl area should be arranged next to the narrow gap area 116. In this embodiment, the third swirl area 115 is next to the narrow gap area 116. In order to maximize the effect of the combustion chamber 100, it is required that the fuel be distributed in a certain proportion to the combustion chamber 100 to form two swirl fuels with opposite swirl directions. When the proportion of the first swirl area 111 distributed by the fuel jet hitting the central boss 120 is too large, the air in the second swirl area 113 cannot be used more; when the proportion is too small, the local fuel-air ratio of the second swirl area 113 is too high, and the air utilization rate of the first swirl area 111 is low. If the third swirl zone 115 is too close to the center boss 120, the fuel sprayed from the upper spray hole of the injector will hit the third swirl zone 115 too early, which is not good for combustion. If the third swirl zone 115 is too far from the center boss 120, the fuel sprayed from the upper spray hole of the injector cannot hit the swirl chamber as quickly as possible to form a diversion, and the advantage of the combustion chamber cannot be brought into play. Therefore, the structure of the third swirl zone 115 and the ratio between the fuel injection amount of the upper spray hole and the fuel injection amount of the lower spray hole should be reasonably determined.

[0031] In one embodiment, the length L of the third swirl zone 115 is (0.076-0.087)D (D is the piston diameter), the distance H between the lowest point of the third swirl zone 115 and the piston top is (0.047-0.062)D, the bottom arc of the second collision zone 114 (i.e., the transition arc between the second swirl zone 113 and the third swirl zone 115) is R1 is (0.013-0.021)D, and the bottom arc of the third swirl zone 115 (i.e., the transition arc between the second collision zone 114 and the top gap zone 116) is R2 is (0.012-0.019)D.

[0032] In one embodiment, the arc surface of the first collision zone 112 is higher than the arc surfaces of the first swirl zone 111 and the second swirl zone 113 .

[0033] In one embodiment, the arc surface of the second collision zone 114 is higher than the arc surfaces of the second swirl zone 113 and the third swirl zone 115 .

[0034] In one embodiment, the arc length of the first collision zone 112 is greater than the arc length of the second collision zone 114 .

[0035] In this embodiment, the arc surface of each collision zone is higher than the vortex zones on both sides, so that the oil beam can be sucked into the vortex zones on both sides after colliding with the collision zone to promote oil-gas mixing.

[0036] In one embodiment, the combustion chamber 110 further includes a narrow gap area 116 , and the narrow gap area 116 is distributed between the third vortex area 115 and the throat of the combustion chamber 100 .

[0037] In one of the embodiments, the thermal EGR component further includes a solenoid valve, a flow meter and a pressure sensor, wherein the solenoid valve is used to control the switch of the EGR pipeline, and the flow meter and the pressure sensor are used to control the flow rate and pressure of the gas in the EGR pipeline, respectively.

[0038] It is understandable that the thermal EGR assembly is not limited to including the above-mentioned components, and can be selected according to needs in actual use.

[0039] like Figure 2 As shown, the working principle of a multi-layer multi-swirling combustion system provided by the present invention is: The oil beam is firstly sprayed on the center boss 120 under the condition of low injection pressure, and is divided into two beams by the piston axis direction of the center boss 120, which are respectively entrained and flow toward the upper and lower parts, thereby promoting the oil-gas mixing of the oil beam in the area near the center boss 120. Then, the flowing oil beam collides with the first collision zone 112 and the second collision zone 114 in turn, and is respectively entrained and flowed toward the first swirl zone 111, the second swirl zone 113 and the third swirl zone 115 on both sides, and is fully mixed with the air. Finally, since the second collision zone 114 and the third swirl zone 115 are provided in the throat area of ​​the combustion chamber 100, this structure can prevent the fuel from rushing out and entering the narrow gap zone 116. On the one hand, it can reduce particle emissions, and on the other hand, it can prevent the fuel from entering the engine oil and causing the engine oil to be diluted. At the same time, the combustion chamber 100 has a constricted structure, which can further improve the oil-gas mixing inside the combustion chamber 100. Figure 3 and Figure 4 This is a diagram of the oil-gas mixture state inside the combustion chamber simulated by computer software. Figure 3 It represents the oil-gas mixture state diagram in the existing combustion chamber cylinder. Figure 4 The diagram representing the oil-gas mixture state in the combustion chamber of the present invention is shown in FIG. Figure 3 and Figure 4 As shown, it is obvious that the technical solution of the present invention can make the fuel be sucked into the third swirl area 115, instead of flowing into the narrow gap area 116 and rushing to the cylinder wall, thereby reducing carbon smoke emissions and preventing oil dilution.

[0040] In addition, the present invention also provides an engine, which includes the multi-layer and multi-swirling combustion system described in the above technical solution of the present invention.

[0041] Furthermore, the present invention further provides a vehicle, comprising the engine provided by the above technical solution of the present invention.

[0042] The multi-layer multi-swirling combustion system, engine and vehicle provided by the present invention have the following beneficial effects: 1. The multi-layer multi-swirling combustion system provided by the present invention has multiple swirling zones and multiple collision zones arranged inside the combustion chamber 100, which can make the oil beam entrained into the combustion chamber 100, effectively preventing the fuel from rushing out and entering the narrow gap zone 116, which can reduce particle emission on the one hand, and prevent the fuel from entering the engine oil, causing oil dilution and piston ring ablation, etc. on the other hand. Therefore, the present invention can reduce particle emission and avoid problems such as oil dilution and piston ring ablation; 2. The present invention provides a multi-layer and multi-vortex combustion system. After the oil beam hits the central boss 120, it is divided into two beams in the axial direction of the piston and flows toward the upper and lower parts respectively, thereby promoting the axial mixing of the oil beams. The throat of the combustion chamber 100 is a constricted type and is located in the upper middle part of the combustion chamber 100, which can improve the air flow movement and oil-gas mixing distribution inside the combustion chamber 100; at the same time, the first collision zone 112 and the second collision zone 114 work together to generate multiple vortices in the combustion chamber 100, thereby improving the oil-gas mixing speed in the entire combustion chamber 100 space and improving the thermal efficiency of the engine. Therefore, the present invention can form multiple vortices in the combustion chamber, improve the oil-gas mixing and distribution in the combustion chamber space, and improve the thermal efficiency of the engine.

[0043] In summary, compared with the prior art, the present invention provides a multi-layer and multi-swirling combustion system, an engine and a vehicle, which adopt a hot EGR component to replace the cold EGR system. Since there is no need to add additional components such as an EGR cooler, the structure of the combustion system is simplified, thereby reducing the cost, and the oxygen content in the exhaust gas is increased, thereby improving the thermal efficiency of the engine; on the other hand, under the conditions of a hot EGR component and a low injection pressure, the present invention designs multiple swirling zones and multiple collision zones in the combustion chamber so that the oil and gas can be fully mixed under multiple collisions and swirling, thereby making the oil and gas reasonably matched, which can improve the formation and distribution of the mixed gas in the cylinder, ensure that the combustion process is fast and sufficient, prevent oil dilution, reduce carbon smoke emissions, and ensure that the engine has a higher thermal efficiency and lower fuel consumption and emission levels.

[0044] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A multi-layer multi-volute combustion system, characterized in that: include: A combustion chamber, comprising a combustion chamber arranged in a mirror image, wherein the combustion chamber is formed with a plurality of vortex areas and a plurality of collision areas, each adjacent two vortex areas are connected by the collision area, and the surface of the collision area is higher than the surface of the vortex area; The hot EGR component comprises an EGR pipe, wherein the EGR pipe is connected to the exhaust end of the combustion chamber to deliver part of the exhaust gas generated by the combustion chamber into the intake manifold.

2. The multi-layer and multi-volute combustion system according to claim 1, characterized in that: A central boss is formed inside the combustion chamber, the axial symmetry center of the central boss coincides with the axial center of the piston of the combustion chamber, and the axial symmetry center of the central boss divides the combustion chamber into two combustion chambers arranged in a mirrored manner.

3. The multi-layer and multi-volute combustion system according to claim 2, characterized in that: The combustion chamber includes a first vortex zone, a first collision zone, a second vortex zone, a second collision zone and a third vortex zone. The first vortex zone, the first collision zone, the second vortex zone, the second collision zone and the third vortex zone are arranged in sequence from the axial symmetry center of the central boss toward the throat of the combustion chamber.

4. The multi-layer and multi-volute combustion system according to claim 3, characterized in that: The arc surface of the first collision area is higher than the arc surfaces of the first swirl area and the second swirl area.

5. The multi-layer and multi-volute combustion system according to claim 4, characterized in that: The arc surface of the second collision zone is higher than the arc surfaces of the second swirling zone and the third swirling zone.

6. The multi-layer and multi-volute combustion system according to claim 5, characterized in that: The arc length of the first collision area is greater than the arc length of the second collision area.

7. The multi-layer and multi-volute combustion system according to claim 6, characterized in that: The combustion chamber further includes a narrow gap area, which is distributed between the third vortex area and the throat of the combustion chamber.

8. The multi-layer and multi-volute combustion system according to claim 1, characterized in that: The hot EGR component also includes a solenoid valve, a flow meter and a pressure sensor. The solenoid valve is used to control the switch of the EGR pipeline, and the flow meter and the pressure sensor are used to control the flow rate and pressure of the gas in the EGR pipeline respectively.

9. An engine, characterized in that: The engine comprises the multi-layer multi-swirl combustion system as claimed in any one of claims 1 to 8.

10. A vehicle, characterized in that: The vehicle includes the engine of claim 9.

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