Engine system and engine combustion organization method

Abstract

The application provides an engine system and an engine combustion organization method, and relates to the technical field of engines.The engine combustion organization method comprises the following steps: the first injection element is arranged close to the axis of the piston element compared with the second injection element; the injection start time of the second fuel is earlier than the injection start time of the first fuel; the first injection element is used for spraying a plurality of first fuel beams, and the intersection of the plurality of first fuel beams and the piston top defines a first range; the second injection element is used for spraying a plurality of second fuel beams, and the intersection of the plurality of second fuel beams and the piston top defines a second range; the second range is located inside the first range, so that when the first fuel beam develops to the piston top, the second fuel in the second fuel beam is combusted in the space formed between the first fuel beam and the piston top. In this way, the pilot ignition of the first fuel can be realized by less second fuel, and then the replacement rate of 95% is helped to be realized, and then the emission of nitrogen oxides is helped to be reduced.

Description

Technical Field

[0001] This invention relates to the field of engine technology, and more specifically, to an engine system and an engine combustion organization method. Background Technology

[0002] With increasing emphasis on environmental protection and increasingly stringent requirements for engine emissions, technologies that use clean fuels to replace traditional fuels have been vigorously developed. For example, methanol-fueled engines are devices that use methanol instead of diesel fuel for combustion and power output.

[0003] Currently, methanol fuel is mainly used in two ways in methanol-fueled engines: port injection and direct injection. Direct injection uses two independent fuel injection systems for diesel and methanol, with methanol as the primary fuel and a small amount of diesel serving only as ignition. In methanol-fueled engines using direct injection, because diesel is needed for ignition, it essentially involves methanol replacing a portion of the diesel fuel in combustion. Current combustion methods cannot achieve a 95% replacement rate, and because diesel is used as ignition fuel for mechanical energy combustion in the cylinder, it still produces a significant amount of nitrogen oxides, which is detrimental to environmental protection. Summary of the Invention

[0004] The purpose of this invention is to provide an engine combustion organization method that can improve the technical problems of difficulty in achieving a 95% replacement rate and the generation of a large amount of nitrogen oxides in the prior art.

[0005] Another objective of this invention is to provide an engine system that can improve the technical problems of existing technologies, such as difficulty in achieving a 95% replacement rate and the generation of a large amount of nitrogen oxides.

[0006] The embodiments of the present invention can be implemented in the following ways:

[0007] An engine combustion organization method is provided for combustion control of an engine body. The engine body includes a first injector, a second injector, a piston, a cylinder head, and a cylinder. The piston is movably disposed within the cylinder, and the piston top of the piston forms a combustion chamber with the cylinder head. The first injector and the second injector are disposed on the cylinder head, and the first injector is used to inject a first fuel into the combustion chamber, and the second injector is used to inject a second fuel into the combustion chamber, the second fuel being used to ignite the first fuel. The engine combustion organization method includes:

[0008] The first injection member is positioned closer to the axis of the piston member than the second injection member;

[0009] The injection of the second fuel begins earlier than the injection of the first fuel;

[0010] The first injector is used to inject a plurality of first fuel jets, the intersection of the plurality of first fuel jets with the piston crown defining a first range; the second injector is used to inject a plurality of second fuel jets, the intersection of the plurality of second fuel jets with the piston crown defining a second range; the second range is located within the first range, such that when the first fuel jets develop to the piston crown, the second fuel in the second fuel jets is confined to combustion within the space formed between the first fuel jets and the piston crown.

[0011] Optionally, the piston top of the piston member includes a convex arc portion and an annular recess distributed around the convex arc portion, and at least two of the plurality of second fuel jets are respectively located on opposite sides of the convex arc portion.

[0012] Optionally, the injection of the second fuel ends later than the injection of the first fuel begins.

[0013] Optionally, the injection pulse width of the second fuel is smaller than that of the injection pulse width of the first fuel.

[0014] Optionally, the injection of the first fuel begins when the flame of the second fuel reaches the center of the combustion chamber.

[0015] Optionally, the first fuel is methanol and the second fuel is diesel.

[0016] An engine system employing the engine combustion organization method described above.

[0017] Optionally, the first injector in the engine system is located at the axis of the piston, and the second injector is spaced apart from the first injector.

[0018] Optionally, the axial direction of the second injection element intersects the axial direction of the piston element.

[0019] Optionally, the first injector has a plurality of injection holes distributed circumferentially along the first injector, and the injection holes are used to eject the first fuel jet; the number of injection holes is 10 or 12.

[0020] The beneficial effects of the engine system and engine combustion organization method provided by the embodiments of the present invention include:

[0021] This invention provides an engine combustion organization method for controlling combustion in an engine body. The engine body includes a first injector, a second injector, a piston, a cylinder head, and a cylinder. The piston is movably disposed within the cylinder, and its piston crown forms a combustion chamber with the cylinder head. The first and second injectors are disposed only on the cylinder head. The first injector injects a first fuel into the combustion chamber, and the second injector injects a second fuel into the combustion chamber, the second fuel igniting the first fuel. The engine combustion organization method includes: the first injector being positioned closer to the piston axis than the second injector; the second fuel injection initiation time being earlier than the first fuel injection initiation time; the first injector ejecting multiple first fuel jets, the intersections of the multiple first fuel jets with the piston crown defining a first range; the second injector ejecting multiple second fuel jets, the intersections of the multiple second fuel jets with the piston crown defining a second range; the second range being located within the first range, such that when the first fuel jets develop to the piston crown, the second fuel in the second fuel jets is confined to the space formed between the first fuel jets and the piston crown for combustion. This allows for the ignition of the first fuel with less second fuel, thus helping to achieve a 95% replacement rate and reduce nitrogen oxide emissions. Furthermore, since the second fuel is confined to the space between the first fuel jet and the piston top for combustion, and since the formation of nitrogen oxides mainly depends on temperature and oxygen, the latent heat of vaporization of the first fuel jet at the upper boundary of the space reduces the combustion temperature of the second fuel. At the same time, the lack of oxygen in this space further inhibits the formation of nitrogen oxides.

[0022] Embodiments of the present invention also provide an engine system that employs the engine combustion organization method described above, thus having the beneficial effect of helping to achieve a 95% replacement rate while effectively reducing nitrogen oxide emissions. Attached Figure Description

[0023] The above-described features and advantages of the present invention will be better understood after reading the following detailed description of embodiments of the present disclosure in conjunction with the accompanying drawings. In the drawings, components are not necessarily drawn to scale, and components having similar related characteristics or features may have the same or similar reference numerals.

[0024] Figure 1 A partial structural schematic diagram of an engine system provided according to one aspect of the present invention is shown;

[0025] Figure 2 A schematic diagram of the injection pulse widths of a first fuel and a second fuel according to an aspect of the present invention is shown;

[0026] Figure 3A schematic diagram is shown showing the development of a flame generated by a second fuel according to an aspect of the present invention to the center of the combustion chamber;

[0027] Figure 4 A schematic diagram is shown showing the first fuel provided according to one aspect of the invention after it has been injected at the optimal injection time;

[0028] Figure 5 A schematic diagram of the injection angles of the first and second fuels provided by one aspect of the present invention is shown.

[0029] Figure label:

[0030] 100 - Engine body; 111 - Piston assembly; 112 - Convex arc portion; 113 - Annular recess; 114 - Cylinder; 115 - Cylinder head; 116 - Combustion chamber; 117 - First injector; 118 - Second injector; 119 - Piston top; 121 - First fuel jet; 122 - Second fuel jet; 123 - Second fuel jet on the left; 124 - Second fuel jet on the right; 125 - Narrow area; 126 - First injection angle; 127 - Second injection angle; 128 - Flame. Detailed Implementation

[0031] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. It should be noted that the aspects described below with reference to the accompanying drawings and specific embodiments are merely exemplary and should not be construed as limiting the scope of protection of the present invention in any way.

[0032] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," "outer," or "vertical" appear, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed when in use, and does not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0033] At the same time, it should be noted that the terms "first" and "second" are used only for distinguishing descriptions and should not be interpreted as indicating or implying relative importance.

[0034] In the description of this invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an integral connection, or a detachable connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or a connection within two components, etc. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0035] Figure 1 This is a partial structural diagram of the engine system provided in this embodiment, and at the same time... Figure 1 The positions of the first fuel beam 121 and the second fuel beam 122 are shown in the diagram. Please refer to... Figure 1 This embodiment provides an engine combustion organization method and an engine system in which the above-mentioned engine combustion organization method is applied. In other words, the engine combustion organization method can also be regarded as being implemented based on the engine body 100 in the engine system and controlling the combustion of the engine body 100.

[0036] In this embodiment, the engine body 100 includes a first injector 117, a second injector 118, a piston 111, a cylinder head 115, and cylinders 114. Specifically, the engine body 100 includes a casing (not shown), with multiple cylinders 114 disposed within the casing. The cylinder head 115 covers the casing and closes the upper openings of the cylinders 114. The piston 111 is movably disposed within the cylinders 114, thereby reciprocating up and down relative to the cylinder head 115. The piston top 119 of the piston 111 forms a combustion chamber 116 with the cylinder head 115, i.e., as shown... Figure 1 In the shown state, the space formed between the piston top 119 and the cylinder head 115 is the combustion chamber 116. The first injector 117 and the second injector 118 are both installed on the cylinder head 115. The first injector 117 injects the first fuel into the combustion chamber 116, and the second injector 118 injects the second fuel into the combustion chamber 116, thereby igniting the first fuel.

[0037] Therefore, the first fuel can be an easily ignited and cleaner fuel, and the second fuel can be a compressibly ignitable fuel. For example, the first fuel may include, but is not limited to, methanol, and the second fuel may include, but is not limited to, diesel. In this case, the engine system is a methanol fuel engine system. The following detailed explanation of the engine combustion organization method will be based on the configuration of methanol as the first fuel and diesel as the second fuel. Correspondingly, in the process of explaining the engine combustion organization method, if the configuration of the engine body 100 is involved, it can also be regarded as the structural configuration of the engine system.

[0038] The engine combustion organization method provided in this embodiment includes:

[0039] 01: Injector Arrangement. The first injector 117 is positioned closer to the axis of the piston member 111 than the second injector 118, meaning the first injector 117 is closer to the center of the combustion chamber 116 than the second injector 118. This allows the multiple first fuel jets 121 ejected by the first injector 117 to be more evenly distributed throughout the combustion chamber 116, while also better confining the second fuel ejected by the second injector 118 within the space enclosed by the multiple first fuel jets 121.

[0040] Optionally, the first injection element 117 is disposed at the axis of the piston element 111, that is, the axis of the first injection element 117 is substantially coincident with the axis of the piston element 111, and the second injection element 118 is disposed at an interval from the first injection element 117, such as... Figure 1 As shown, in this embodiment, the second spray member 118 is located to the right of the first spray member 117. It can be understood that in some other embodiments, the second spray member 118 may also be located to the left of the first spray member 117.

[0041] Furthermore, the second injection element 118 is arranged at an angle, specifically, the axial direction of the second injection element 118 intersects the axial direction of the piston element 111.

[0042] 02: Second fuel injection parameter settings:

[0043] 21: Injection timing: The injection of the second fuel begins earlier than the injection of the first fuel.

[0044] Optionally, Figure 2 This embodiment illustrates an exemplary injection pulse width for a first fuel and a second fuel, based on... Figure 2 As can be seen, in this embodiment, the injection start time of the second fuel is earlier than the injection start time of the first fuel, and the injection end time of the second fuel is later than the injection start time of the first fuel. The injection pulse width of the second fuel is smaller than that of the first fuel. Specifically, the injection pulse width refers to the crankshaft rotation angle corresponding to the injection process. This effectively ensures that the second fuel injection has not ended when the first fuel injection begins.

[0045] 22: Injection Angle: To ensure that the second fuel can effectively ignite the first fuel, the injection angle of the second injector 118 should be as small as possible. The injection angle of the second injector 118 is 127°. Specifically, as follows... Figure 5 As shown, the second injection angle 127 is the angle formed by the axes of the two opposing second fuel jets 122.

[0046] Optionally, such as Figure 1As shown, in this embodiment, the piston top 119 of the piston member 111 includes a convex arc portion 112 and an annular recess 113 distributed around the convex arc portion 112, and at least two of the plurality of second fuel jets 122 are respectively located on opposite sides of the arc protrusion.

[0047] Specifically, the convex arc portion 112 is located at the center of the piston member 111, and the second injector 118 is positioned to the right of the center of the piston member 111. Therefore, the diesel fuel injected by the second injector 118 is located to the right of the convex arc portion 112. To ensure the ignition of the first fuel on the left side of the convex arc portion 112, the injection angle of the second fuel should ensure that at least a portion of the second fuel jet 122 passes over the convex arc portion 112 and is injected to the left side of the convex arc portion 112. That is, at least two of the aforementioned plurality of second fuel jets 122 are the left fuel jet 123 and the right fuel jet 124, respectively. It is understood that in some other embodiments, the second injector 118 may also be located to the left of the convex arc portion 112. In this case, the injection angle of the second injector 118 should be set such that a portion of the second fuel jet 122 passes over the convex arc portion 112 and is injected to the right side of the convex arc portion 112. Under this condition, the injection angle of the second injector 118 can be set as small as possible, so that the spatial distribution of the second fuel is as close as possible to the center of the piston member 111.

[0048] Furthermore, in order to ensure that the amount of diesel fuel injected can be controlled at a relatively small value, the injection pressure of the second fuel should be as high as possible so that the second fuel can quickly start to release heat after entering the cylinder.

[0049] 03: Injection parameters of the first fuel.

[0050] 31: Injection timing: The injection start time of the first fuel is later than the injection start time of the second fuel.

[0051] like Figure 2 The relationship between the injection start-stop times of the first fuel and the injection start-stop times of the second fuel in this embodiment is shown.

[0052] Based on the fact that the injection start time of the first fuel is later than the injection start time of the second fuel, there is further an optimal value for the injection interval between the first fuel and the second fuel. Specifically, the optimal injection time of the first fuel is when the flame 128 generated by the second fuel develops to the center of the combustion chamber 116 (i.e., the axial position of the piston 111). Figure 3 This diagram shows a schematic of the flame 128 generated by the second fuel provided in this embodiment developing to the center of the combustion chamber 116. Figure 4 This diagram illustrates the first fuel provided in this embodiment after it is injected at the optimal injection time. According to... Figure 3 and Figure 4It can be seen that when the first fuel starts to be injected at the optimal injection time, the first fuel jet 121 comes into direct contact with the flame 128 generated by the second fuel attached to the first injector 117. At this time, the second fuel releases heat in a concentrated manner, and the first fuel jet 121 is ignited by passing through the flame 128 generated by the second fuel.

[0053] 32: Jet angle.

[0054] The first injector 117 is used to inject a plurality of first fuel jets 121, each consisting of a first fuel stream. The intersection of the plurality of first fuel jets 121 with the piston crown 119 defines a first range. The second injector 118 is used to inject a plurality of second fuel jets 122, each consisting of a second fuel stream. The intersection of the plurality of second fuel jets 122 with the piston crown 119 defines a second range. The injection angle of the first injector 117 should be set such that the first range surrounds the second range, i.e., the second range is located within the first range. Thus, when the first fuel jets 121 reach the piston crown 119, the second fuel in the second fuel jets 122 is confined within the space formed between the first fuel jets 121 and the piston crown 119 (i.e.,...). Figure 1 Combustion occurs within the area circled by the dashed line. The injection angle of the first injector 117 is 126°, specifically, as shown... Figure 5 As shown, the first injection angle 126 is the angle formed by the axes of the two opposing first fuel jets 121.

[0055] Because the space formed between the first fuel jet 121 and the piston top 119 is relatively small, this space can also be referred to as the narrow region 125. Since the subsequent combustion of the second fuel is completed within this narrow region 125, and the formation of nitrogen oxides mainly depends on temperature and oxygen, when the second fuel burns within the narrow region 125, the latent heat of vaporization of the first fuel jet 121 at the upper boundary of the narrow region 125 will reduce the combustion temperature of the second fuel. At the same time, the narrow region 125 is oxygen-deficient, thereby inhibiting the formation of nitrogen oxides.

[0056] Optionally, the first injector 117 is provided with a plurality of injection holes, which are distributed along the axial direction of the first injector 117 and are used to eject the first fuel jet 121. The number of injection holes on the first injector 117 should be as large as possible. A larger number of injection holes results in a larger number of first fuel jets 121 ejected by the first injector 117. Correspondingly, the sealing of the narrow area 125 enclosed by the first fuel jets 121 is better, thereby better confining the second fuel within the narrow area 125 for combustion. Optionally, the number of injection holes on the first injector 117 can be set to 10 or 12.

[0057] Optionally, the full atomization of the first fuel by the first injector 117 also helps to improve the sealing of the confined area 125.

[0058] It should be noted that in the description of this embodiment, the serial numbers such as "01, 02, 03" are only used to arrange the various settings in the engine combustion organization method, and do not indicate or imply relative importance.

[0059] The engine system and engine combustion organization method provided by the embodiments of the present invention, by setting the injection timing characteristics of the first fuel and the second fuel that ignites the first fuel, as well as the spatial characteristics of the fuel distribution in the cylinder, help the direct injection engine system achieve a 95% replacement rate of the first fuel, and further reduce nitrogen oxide emissions, making it cleaner and more environmentally friendly.

[0060] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An engine combustion organization method for combustion control of an engine body, the engine body including a first injector, a second injector, a piston, a cylinder head and a cylinder, the piston being movably disposed within the cylinder, the piston top of the piston being used to form a combustion chamber with the cylinder head; The first injector and the second injector are disposed on the cylinder head, and the first injector is used to inject a first fuel into the combustion chamber, and the second injector is used to inject a second fuel into the combustion chamber, the second fuel being used to ignite the first fuel; characterized in that, The engine combustion organization method includes: The first injection member is positioned closer to the axis of the piston member than the second injection member; The injection of the second fuel begins earlier than the injection of the first fuel; The first injector is used to inject a plurality of first fuel jets, the intersection of the plurality of first fuel jets with the piston crown defining a first range; the second injector is used to inject a plurality of second fuel jets, the intersection of the plurality of second fuel jets with the piston crown defining a second range; the second range is located within the first range, such that when the first fuel jets develop to the piston crown, the second fuel in the second fuel jets is confined to combustion within the space formed between the first fuel jets and the piston crown.

2. The engine combustion organization method according to claim 1, characterized in that, The piston top of the piston assembly includes a convex arc portion and an annular recess distributed around the convex arc portion, and at least two of the plurality of second fuel jets are respectively located on opposite sides of the convex arc portion.

3. The engine combustion organization method according to claim 1, characterized in that, The injection of the second fuel ends later than the injection of the first fuel begins.

4. The engine combustion organization method according to claim 3, characterized in that, The injection pulse width of the second fuel is smaller than that of the first fuel.

5. The engine combustion organization method according to claim 1, characterized in that, The injection of the first fuel begins when the flame of the second fuel reaches the center of the combustion chamber.

6. The engine combustion organization method according to claim 1, characterized in that, The first fuel is methanol, and the second fuel is diesel.

7. An engine system, characterized in that, The engine system employs the engine combustion organization method according to any one of claims 1-6.

8. The engine system according to claim 7, characterized in that, The first injector in the engine system is located at the axis of the piston, and the second injector is spaced apart from the first injector.

9. The engine system according to claim 8, characterized in that, The axial direction of the second injection component intersects the axial direction of the piston component.

10. The engine system according to claim 7, characterized in that, The first injector has a plurality of injection holes distributed circumferentially along the first injector and the injection holes are used to eject the first fuel jet; the number of injection holes is 10 or 12.

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