CN117927366A - Special internal combustion engine for high-pressure low-temperature lean combustion methanol and application method thereof - Google Patents
Special internal combustion engine for high-pressure low-temperature lean combustion methanol and application method thereof Download PDFInfo
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- CN117927366A CN117927366A CN202410143455.2A CN202410143455A CN117927366A CN 117927366 A CN117927366 A CN 117927366A CN 202410143455 A CN202410143455 A CN 202410143455A CN 117927366 A CN117927366 A CN 117927366A
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- mounting groove
- piston
- combustion chamber
- methanol
- internal combustion
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- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 title claims abstract description 132
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 100
- 238000000034 method Methods 0.000 title claims abstract description 8
- 239000000446 fuel Substances 0.000 claims abstract description 24
- 238000007906 compression Methods 0.000 claims abstract description 23
- 230000006835 compression Effects 0.000 claims abstract description 19
- 238000002347 injection Methods 0.000 claims description 19
- 239000007924 injection Substances 0.000 claims description 19
- 238000007789 sealing Methods 0.000 claims description 7
- 239000000203 mixture Substances 0.000 claims description 4
- 239000007921 spray Substances 0.000 claims description 4
- 230000007613 environmental effect Effects 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 15
- 239000003502 gasoline Substances 0.000 description 10
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 6
- 239000000126 substance Substances 0.000 description 5
- 239000000243 solution Substances 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 238000000889 atomisation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 239000002283 diesel fuel Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 239000002737 fuel gas Substances 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- TVMXDCGIABBOFY-UHFFFAOYSA-N octane Chemical compound CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 description 1
- 239000013618 particulate matter Substances 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
Abstract
The invention provides a high-pressure low-temperature lean-burn methanol special internal combustion engine and an application method thereof, and relates to the technical field of methanol internal combustion engines. The special internal combustion engine for the high-pressure low-temperature lean combustion methanol comprises a cylinder body, a cylinder cover and a piston; the cylinder cover is fixedly connected with the cylinder body; the piston is connected with the cylinder body in a sliding way; the cylinder body, the cylinder cover and the piston form a combustion chamber; the cylinder cover is sequentially provided with a first mounting groove, a second mounting groove, a third mounting groove and a fourth mounting groove; the first mounting groove is provided with an exhaust valve; the second mounting groove is provided with a spark plug, and the discharge end of the spark plug is arranged in the combustion chamber; the third mounting groove is provided with an air inlet valve; the fourth mounting groove is provided with an oil nozzle; the combustion chamber is added by sections through the high compression ratio design of the cylinder body and the methanol fuel, so that the internal combustion engine has the functions of high heat efficiency and environmental protection. The special internal combustion engine for the high-pressure low-temperature lean combustion methanol and the method thereof solve the technical problem that the existing internal combustion engine cannot achieve both high heat efficiency and low emission.
Description
Technical Field
The invention relates to the technical field of methanol internal combustion engines, in particular to a high-pressure low-temperature lean-burn methanol special internal combustion engine.
Background
Currently, most internal combustion engines use gasoline or diesel as raw materials.
The gasoline has good volatility and antiknock performance, is suitable for a premixed flame propagation combustion mode of the gasoline engine, has high volatility, can ensure that the gasoline engine is fully mixed with air in a combustion chamber, but the compression ratio of the gasoline engine cannot be too high (generally not more than 12), otherwise knocking still occurs, and the low compression ratio leads to lower thermal efficiency of the gasoline engine.
The diesel oil has the characteristics of poor antiknock property, difficult volatilization and good spontaneous combustion, is suitable for a diffusion combustion mode of compression ignition direct injection, namely, a high compression ratio (between 17 and 25), has higher thermal efficiency of high thermal cycle, but cannot form homogeneous mixed gas after being injected into a cylinder due to poor volatility, and atomization and diffusion combustion of liquid drops are carried out simultaneously, so that the diesel engine is incomplete in combustion, unburned hydrocarbon and particulate matter are amplified, and environmental protection is not facilitated.
Methanol is a low-carbon, small-molecular and oxygen-containing liquid fuel, has higher antiknock property than gasoline and better volatility than diesel, and needs to be an internal combustion engine with high heat efficiency of a diesel engine and clean combustion of the gasoline engine at the same time in order to fully utilize the good characteristics of the methanol.
Disclosure of Invention
The invention aims to provide a special internal combustion engine for high-pressure low-temperature lean combustion methanol and an application method thereof, which solve the technical problem that the existing internal combustion engine cannot achieve both high heat efficiency and low emission.
The invention adopts the scheme that:
The invention provides a special internal combustion engine for high-pressure low-temperature lean combustion methanol, which comprises a cylinder body, a cylinder cover and a piston, wherein the cylinder body is provided with a cylinder cover; the cylinder cover is fixedly connected with the cylinder body; the piston is connected with the cylinder body in a sliding way; the cylinder body, the cylinder cover and the piston form a combustion chamber; the cylinder cover is sequentially provided with a first mounting groove, a second mounting groove, a third mounting groove and a fourth mounting groove; the first mounting groove is provided with an exhaust valve; the second mounting groove is provided with a spark plug, and the discharge end of the spark plug is arranged in the combustion chamber; the third mounting groove is provided with an air inlet valve; and the fourth mounting groove is provided with an oil nozzle, and the output end of the oil nozzle is close to the top angle of the combustion chamber.
Further, the piston is provided with a groove.
Further, the piston is provided with a sealing strip.
An application method of an internal combustion engine special for high-pressure low-temperature lean combustion methanol comprises the following steps:
Step one: the piston contracts in the cylinder body for the first time, and the combustion chamber starts to intake air; step two: the piston is compressed for the first time in the cylinder body, in the first compression process of the piston, the fuel injection nozzle starts to inject methanol fuel into the combustion chamber in the first stage, the fuel injection advance angle in the first stage is between-CABTDC, and the chemical equivalent ratio of mixed gas is between-, wherein the compression ratio of the cylinder body is-; step three: after the piston finishes the first compression of the cylinder body, the oil nozzle starts to spray methanol fuel into the combustion chamber in the second stage, and the oil injection advance angle of the second stage is between-CABTDC, so that the stoichiometric ratio of the mixed gas is between-; step four: when the oil injection stage of the second stage of the oil injection nozzle is finished, the spark plug is ignited to ignite the mixed gas in the combustion chamber to burn, and the piston is contracted in the cylinder body for the second time; step five: the piston is compressed for the second time in the cylinder body, and exhaust gas in the combustion chamber is discharged.
The beneficial effects are that: the special internal combustion engine for high-pressure low-temperature lean combustion methanol can use pure methanol as fuel, adopts a low-temperature combustion mode, has low temperature in an ignition area of an igniter and low emission of nitrogen oxides, and can realize low emission under the condition of not adopting any tail gas aftertreatment device; the compression ratio is 18-22, which is higher than that of traditional gasoline engine, and the chemical equivalent ratio of mixed gas is 0.4-0.8, so that the special internal combustion engine for high-pressure low-temperature lean combustion methanol has high thermal efficiency.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.
Fig. 1 is a sectional view of an internal combustion engine special for high-pressure low-temperature lean-burn methanol in a first operating state provided in this embodiment;
Fig. 2 is a sectional view of the internal combustion engine special for high-pressure low-temperature lean-burn methanol in a second operating state provided in the present embodiment;
Fig. 3 is a cross-sectional view of the internal combustion engine special for high-pressure low-temperature lean-burn methanol in a third operating state provided in this embodiment.
Icon:
100-cylinder block; 110-a combustion chamber;
200-cylinder cover; 210-a first mounting groove; 220-a second mounting slot; 230-a third mounting groove; 240-fourth mounting groove; 250-exhaust valve; 260-spark plug; 270-intake valve; 280-oil nozzle;
300-piston; 310-groove; 320-sealing strips.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
In the description of the present invention, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or are directions or positional relationships conventionally put in use of the inventive product, are merely for convenience of describing the present invention and simplifying the description, and are not indicative or implying that the apparatus or element to be referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.
Furthermore, the terms "horizontal," "vertical," and the like do not denote a requirement that the component be absolutely horizontal or overhanging, but may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the description of the present invention, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
Some embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following embodiments and features of the embodiments may be combined with each other without conflict.
The embodiment provides a high-pressure low-temperature lean-burn methanol special internal combustion engine, referring to fig. 1-3, comprising a cylinder block 100, a cylinder head 200 and a piston 300; the cylinder head 200 is fixedly connected with the cylinder block 100; the piston 300 is slidably coupled to the cylinder block 100; the cylinder block 100 forms a combustion chamber 110 with the cylinder head 200 and the piston 300; the cylinder head 200 is provided with a first mounting groove 210, a second mounting groove 220, a third mounting groove 230, and a fourth mounting groove 240 in this order; the first mounting groove 210 is mounted with an exhaust valve 250; the second mounting groove 220 is mounted with a spark plug 260, and a discharge end of the spark plug 260 is disposed in the combustion chamber 110; the third mounting groove 230 is mounted with an intake valve 270; the fourth mounting groove 240 is provided with an oil nozzle 280, and an output end of the oil nozzle 280 is close to a top corner of the combustion chamber 110.
Specifically, the cylinder head 200 is screwed with the cylinder block 100; the piston 300 is slidably coupled to the cylinder block 100 to allow the combustion chamber 110 to suck, discharge or compress gas; the intake valve 270 is to suck air into the engine and mix with methanol fuel; the exhaust valve 250 is used for exhausting and radiating the generated waste gas after the combustion of the methanol fuel; the spark plug 260 is used for igniting the mixed gas in the combustion chamber 110, and the discharge end of the spark plug 260 is close to the inner side surface of the cylinder head 200; the output end of the oil nozzle 280 is close to the top angle of the combustion chamber 110, so that the injected methanol can be mixed with the gas in the combustion chamber 110 more fully; when the combustion chamber 110 is used, the piston 300 is contracted for the first time, the combustion chamber 110 sucks air through the air inlet valve 270, the piston 300 is compressed for the first time, the fuel spray nozzle 280 sprays methanol to the combustion chamber 110 for two times, the first time is in the first compression process, the second time is after the first compression is finished, the chemical equivalent of the mixed gas after the first compression is finished is between 0.4 and 0.8, the combustion chamber 110 can be ensured to discharge fewer pollutants because of the good volatility of the methanol, a lean combustion mode can be adopted, the temperature of an ignition area is lower, and the emission of nitrogen oxides is fewer.
In this embodiment, the piston 300 is provided with a recess 310.
Specifically, the arrangement of the grooves 310 makes the contact area between the piston 300 and the combustion chamber 110 larger, so that the internal combustion engine special for high-pressure low-temperature lean-burn methanol can operate more stably under the condition of high compression ratio.
In this embodiment, the piston 300 is provided with a sealing strip 320.
Specifically, the sealing strips 320 adopt annular sealing strips 320, and two sealing strips are arranged, so that the tightness of the combustion chamber 110 is ensured.
An application method of an internal combustion engine special for high-pressure low-temperature lean combustion methanol is shown in fig. 1-3, and comprises the following steps: step one: the piston 300 is contracted for the first time in the cylinder block 100, and the combustion chamber 110 starts to intake air; step two: the piston 300 is compressed for the first time in the cylinder block 100, and in the first compression process of the piston 300, the fuel injection nozzle 280 starts to inject methanol fuel into the combustion chamber 110 in the first stage, and the injection advance angle in the first stage is between 250 and 160CABTDC, so that the stoichiometric ratio of the mixed gas is between 0.3 and 0.6, wherein the compression ratio of the cylinder block 100 is between 18 and 22; step three: after the first compression of the cylinder block 100 is finished, the fuel injection nozzle 280 starts to inject methanol fuel into the combustion chamber 110 in the second stage, and the injection advance angle of the second stage is 120-50CABTDC, so that the stoichiometric ratio of the mixed gas is 0.4-0.8; step four: when the second stage injection stage of the injection nozzle 280 is completed, the ignition plug 260 is ignited to ignite the mixture in the combustion chamber 110 for combustion, and the piston 300 is contracted in the cylinder block 100 for the second time; step five: the piston 300 is compressed in the cylinder block 100 for the second time, and discharges the exhaust gas in the combustion chamber 110.
Specifically, the first contraction of the piston 300 causes the combustion chamber 110 to draw in air, providing oxygen for the combustion of methanol; the compression ratio of the cylinder block 100 is 18-22, which is higher than the compression ratio (< 12) of the traditional gasoline engine, the traditional ignition flame propagation ignition mode is that if the compression ratio is too high, the combustion is easy to happen in a high temperature area near the wall of the cylinder block 100 and far away from the spark plug 260, so as to knock, the internal combustion engine can improve the compression ratio, meanwhile, knocking is not happened, the high octane number (112) of pure methanol is used as fuel to inhibit knocking, on the other hand, the internal combustion engine adopts a multi-stage injection lean combustion technology, when the fuel nozzle 280 injects methanol fuel in the first stage, the mixture firstly reaches the position near the wall of the cylinder block 100 far away from the spark plug 260, but the chemical equivalent ratio is 0.3-0.6, knocking is not happened, when the fuel nozzle 280 injects methanol fuel in the second stage, the fuel concentration near the spark plug 260 is improved, the chemical equivalent ratio in the whole cylinder is 0.4-0.8, and the vicinity of the spark plug 260 is higher, so that the internal combustion engine has higher thermal efficiency; the oil injection advance angle of the first stage is between 250 and 160CABTDC so as to ensure that more methanol enters the combustion chamber 110 and is fully mixed with air, and meanwhile, knocking is prevented, and the oil injection advance angle of the second stage is between 120 and 50CABTDC so as to supplement methanol fuel, so that the heat efficiency of the internal combustion engine is higher; the ignition plug 260 ignites the fuel gas of the combustion chamber 110 to retract the piston 300, the piston 300 is compressed in the cylinder block 100 for the second time, and the exhaust gas in the combustion chamber 110 is discharged, and one operation is completed.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (4)
1. The internal combustion engine special for high-pressure low-temperature lean combustion methanol is characterized by comprising a cylinder body (100), a cylinder cover (200) and a piston (300);
the cylinder head (200) is fixedly connected with the cylinder block (100);
the piston (300) is in sliding connection with the cylinder block (100);
-the cylinder block (100) forms a combustion chamber (110) with the cylinder head (200) and the piston (300);
the cylinder cover (200) is sequentially provided with a first mounting groove (210), a second mounting groove (220), a third mounting groove (230) and a fourth mounting groove (240);
The first mounting groove (210) is provided with an exhaust valve (250);
The second mounting groove (220) is provided with a spark plug (260), and a discharge end of the spark plug (260) is arranged in the combustion chamber (110);
the third mounting groove (230) is provided with an air inlet valve (270);
the fourth mounting groove (240) is provided with an oil nozzle (280), and the output end of the oil nozzle (280) is close to the top angle of the combustion chamber (110).
2. The internal combustion engine special for high-pressure low-temperature lean-burn methanol according to claim 1, wherein the piston (300) is provided with a groove (310).
3. The internal combustion engine special for high-pressure low-temperature lean-burn methanol according to claim 2, wherein the piston (300) is provided with a sealing strip (320).
4. An application method of the internal combustion engine special for high-pressure low-temperature lean-burn methanol according to claim 3, comprising the following steps:
Step one: -said piston (300) is contracted for the first time inside said cylinder block (100), said combustion chamber (110) starting the intake;
Step two: the piston (300) is compressed for the first time in the cylinder block (100), and in the first compression process of the piston (300), the oil nozzle (280) starts to spray methanol fuel into the combustion chamber (110) in the first stage, wherein the oil injection advance angle of the first stage is between 250 and 160CABTDC, so that the stoichiometric ratio of mixed gas is between 0.3 and 0.6, and the compression ratio of the cylinder block (100) is 18 to 22;
Step three: after the first compression of the cylinder body (100) is finished, the fuel injection nozzle (280) starts to inject methanol fuel into the combustion chamber (110) in the second stage, and the injection advance angle of the second stage is 120-50CABTDC, so that the stoichiometric ratio of the mixed gas is 0.4-0.8;
Step four: when the second-stage oil injection stage of the oil nozzle (280) is finished, the spark plug (260) ignites to ignite the mixture in the combustion chamber (110) for combustion, and the piston (300) contracts in the cylinder block (100) for the second time;
Step five: the piston (300) is compressed in the cylinder block (100) for the second time, and discharges the exhaust gas in the combustion chamber (110).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410143455.2A CN117927366A (en) | 2024-02-01 | 2024-02-01 | Special internal combustion engine for high-pressure low-temperature lean combustion methanol and application method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410143455.2A CN117927366A (en) | 2024-02-01 | 2024-02-01 | Special internal combustion engine for high-pressure low-temperature lean combustion methanol and application method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117927366A true CN117927366A (en) | 2024-04-26 |
Family
ID=90761064
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410143455.2A Pending CN117927366A (en) | 2024-02-01 | 2024-02-01 | Special internal combustion engine for high-pressure low-temperature lean combustion methanol and application method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117927366A (en) |
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2024
- 2024-02-01 CN CN202410143455.2A patent/CN117927366A/en active Pending
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