CN110017213A - Improve dual fuel engine combustion chamber and the combustion method of gaseous fuel lean burn - Google Patents
Improve dual fuel engine combustion chamber and the combustion method of gaseous fuel lean burn Download PDFInfo
- Publication number
- CN110017213A CN110017213A CN201910109065.2A CN201910109065A CN110017213A CN 110017213 A CN110017213 A CN 110017213A CN 201910109065 A CN201910109065 A CN 201910109065A CN 110017213 A CN110017213 A CN 110017213A
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- Prior art keywords
- combustion chamber
- fuel
- gaseous fuel
- gaseous
- air
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D19/00—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
- F02D19/06—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed
- F02D19/0639—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed characterised by the type of fuels
- F02D19/0642—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed characterised by the type of fuels at least one fuel being gaseous, the other fuels being gaseous or liquid at standard conditions
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D19/00—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
- F02D19/06—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed
- F02D19/08—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed simultaneously using pluralities of fuels
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/30—Use of alternative fuels, e.g. biofuels
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Combustion Methods Of Internal-Combustion Engines (AREA)
- Output Control And Ontrol Of Special Type Engine (AREA)
- Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
Abstract
A kind of design method for the dual fuel engine combustion chamber improving gaseous fuel lean burn, it is for being burnt in a combustion chamber by the main gas charge including gaseous fuel and the mixed Daqu of air, and cause the burning of the main gas charge by lighting the liquid fuel being directly injected in combustion chamber, the liquid fuel is gasoline, and spark plug is arranged in the combustion chamber to light gasoline.The dual fuel engine combustion chamber of improvement gaseous fuel lean burn of the invention and combustion method, only need simply to change the chamber structure of primary motivation, it does not need to light the diesel fuel of injection by compression ignition, spontaneous combustion will not occur to early and lead to the risk of engine damage.
Description
Technical field
The present invention relates to a kind of bi-fuel internal combustion engines.More particularly to one kind in a combustion chamber by lighting direct spray
The liquid fuel in combustion chamber is mapped to cause the improvement gas of the burning for the main gas charge being made of gaseous fuel and air mixing
The dual fuel engine combustion chamber of fuel lean burn and combustion method.
Background technique
It is desirable to use the gaseous fuels such as natural gas, propane and methane to drive engine, these gaseous fuels
Be easy it is a large amount of obtain and compared with HC and CO discharge amount extremely low gasoline or diesel oil, there are the potentiality more burnt cleanly.So
And using normal combustion, the engine run on this gas will generate NOx, in order to be reduced by reducing ignition temperature
NOx, it is preferred to use thinner mixture (being lower than stoichiometry).
The problem of lean mixture, is that they are difficult to only reliably light by plug ignition.For this reason, first
The dual fuel engine of the preceding burning for having proposed to start using diesel injection diluted gas fuel and air mixture.This hair
Motivation must be such that the diesel fuel of injection lights by compression ignition using high compression ratio.
If the compression ignition of diesel fuel is worked in a manner of identical with strong spark, uniform lean fuel passes through
Flame propagation and burn, this cause generate NOx localized high temperature regions.Moreover, if the compression temperature of homogeneous lean fuel is high,
In the presence of spontaneous combustion occurs to early and leads to the risk of engine damage.
Summary of the invention
The technical problem to be solved by the invention is to provide a kind of engine do not need high compression ratio being capable of reliable place
The dual fuel engine combustion chamber and burning side of the improvement gaseous fuel lean burn of the lean mixture of combustion gas fluid fuel and air
Method.
The technical scheme adopted by the invention is that: a kind of dual fuel engine combustion chamber improving gaseous fuel lean burn
Design method, be for burn in a combustion chamber by include gaseous fuel and air mixed Daqu main gas charge, and lead to
It crosses and lights the liquid fuel that is directly injected in combustion chamber to cause the burning of the main gas charge, the liquid fuel is vapour
Oil, and spark plug is set in the combustion chamber to light gasoline.
The gasoline is directly injected in combustion chamber, and to generate layer inflation, gasoline is concentrated near spark plug.
The gaseous mixture of the gaseous fuel and air is less than the lean mixture of the gaseous mixture stoichiometric ratio.
The air enters air intake duct by turbocharger or mechanical supercharger pressurization.
Gaseous fuel makes the gaseous mixture of gaseous fuel and air being uniformly pre-mixed enter combustion by being injected into air intake duct
Burn room.
So that promote the kindling of homogeneous gas fuel and air mixture, gasoline only starts to fire after plug ignition
It burns, the hot waste gas from a upper burn cycle is kept in the combustion chamber or be reintroduced back to combustion chamber during subsequent circulation,
To increase the temperature of the gaseous mixture of gaseous fuel and air in subsequent circulation.
Being reintroduced back to for the hot waste gas is realized by opening simultaneously the intake and exhaust valves of combustion chamber.
The gaseous fuel is selected from any one of natural gas, propane and methane or two or more.
Dual fuel engine is four-stroke engine.
Dual fuel engine is two stroke engine.
A kind of combustion method for the dual fuel engine combustion chamber improving gaseous fuel lean burn, the main gas charge of combustion chamber
It is the gaseous mixture of gaseous fuel and air, the main gas charge fills uniformly with combustion chamber, compresses the main gas charge, and compressing
At the end of gasoline is directly injected in combustion chamber, by the gaseous mixture of spark ignitor gasoline and air charge, to light
Main gas charge.
Direct injected petrol enters for generating the mixture of layering gasoline and air charge, the gasoline in the combustion chamber
Spark plug is first passed around when combustion chamber.
The dual fuel engine combustion chamber of improvement gaseous fuel lean burn of the invention and combustion method, do not need to use
High compression ratio lights the diesel fuel of injection by compression ignition, generates the gasoline of layering by gasoline direct and air fills
The mode of amount improves gaseous fuel lean burn, this advantageously reduces NO come the diluted gas fuel that ignitesXCleaning combustion is realized in discharge
It burns.At the same time, improve the dual fuel engine combustion chamber of gaseous fuel lean burn and combustion method is filled in by spark
Row igniting can be good at controlling lighting for liquid fuel, spontaneous combustion will not occur to early, while also can be well protected engine
Work, avoid the damage of engine.
Detailed description of the invention
Fig. 1 is using the schematic diagram of a cylinder of the internal combustion engine of method of the invention, which sprays with gasoline direct
Oily device and at least one gaseous-fuel injector in air inlet；
Fig. 2 is the various valve opening diagrams that high-temperature internal EGR (internal exhaust gas recirculation) is realized in four-stroke engine.
In figure
10: cylinder 12: piston
14: connecting rod 16: combustion chamber
18: spark plug 20: liquid fuel injector
22: intake valve 24: exhaust valve
25: cylinder head 26: gaseous-fuel injector
28: admission cam 30: exhaust cam
32: air inlet
Specific embodiment
It burns below with reference to dual fuel engine of the embodiment and attached drawing to improvement gaseous fuel lean burn of the invention
The design method of room is described in detail.
The design method of the dual fuel engine combustion chamber of improvement gaseous fuel lean burn of the invention, is for firing
It burns and is burnt in room by the main gas charge including gaseous fuel and the mixed Daqu of air, and be directly injected to combustion chamber by lighting
In liquid fuel cause the burning of the main gas charge, the liquid fuel is gasoline, and setting fire in the combustion chamber
Hua Sai is to light gasoline.The gaseous fuel is selected from any one of natural gas, propane and methane or two or more.It is described
Gasoline be directly injected in combustion chamber, to generate layer inflation, gasoline is concentrated near spark plug.The gaseous fuel and sky
The gaseous mixture of gas is less than the lean mixture of the gaseous mixture stoichiometric ratio.The air passes through turbocharger or mechanical increasing
Depressor pressurization enters air intake duct.
Gaseous fuel makes the gaseous mixture of gaseous fuel and air being uniformly pre-mixed enter combustion by being injected into air intake duct
Burn room.
The present invention is in order to promote the kindling of homogeneous gas fuel and air mixture, just gasoline is only after plug ignition
Start to burn, the hot waste gas from a upper burn cycle is kept in the combustion chamber or be reintroduced back to combustion during subsequent circulation
Room is burnt, to increase the temperature of the gaseous mixture of gaseous fuel and air in subsequent circulation.It is by opening simultaneously combustion chamber
Intake and exhaust valves realize being reintroduced back to for the hot waste gas.In this case, selected compression ratio and adjusting
The point of condition needed for the temperature and pressure of gaseous mixture is set as slightly below spontaneous combustion by hot EGR amount.Then, the spark of the gasoline of injection
Igniting increases temperature and pressure sufficiently, to generate the necessary condition for lighting dilute homogeneous mixture automatically, so as to control certainly
The timing of dynamic igniting.
Heretofore described dual fuel engine is four-stroke engine or two stroke engine.
The combustion method of the dual fuel engine combustion chamber of improvement gaseous fuel lean burn of the invention, combustion chamber
Main gas charge is the main gas charge of the mixed Daqu by gaseous fuel and air, and the main gas charge fills uniformly with combustion chamber, compression
The main gas charge, and gasoline is directly injected in combustion chamber at the end of compression, pass through spark ignitor gasoline and air
Inflation, to light main gas charge.Direct injected petrol for generating layering gasoline and air charge, the gasoline in the combustion chamber
Spark plug is first passed around when into combustion chamber.
Here is detailed description of preferred embodiment:
Fig. 1 gives the schematic diagram of the cylinder 10 of the reciprocating internal combustion engine with 2 stroke cycles or the operation of 4 stroke cycles.It is logical
It crosses connecting rod 14 and is connected to the piston 12 of crankshaft and move back and forth in cylinder 10 to limit ECC Expansion Combustion Chamber 16.Combustion chamber 16 has
The intake valve 22 for thering is at least one to be operated by admission cam 28 and an exhaust valve 24 operated by exhaust cam 30.It is arranged in gas
Liquid fuel is directly injected in combustion chamber 16 by the liquid fuel injector 20 of the direct injecting LPG in liquefied condition in cylinder cap 25, and
And the igniting for the liquid fuel that spark plug 18 is used to be ejected into operating room is set.Gaseous-fuel injector 26 is by natural gas supply
The uniform lean mixture of premix of natural gas and air is formed into the air inlet 32 of air intake duct.Engine can also have one
Or multiple turbocharger or mechanical supercharger, these turbocharger or mechanical supercharger are not shown.Turbocharging
Device and mechanical supercharger are inessential for the present invention, and assume that and operate in a usual manner.Liquid fuel injector 20 is such as
Shown in Fig. 1, to be arranged close to spark plug 18, but liquid fuel injector 20 can be alternatively arranged in the side of combustion chamber
Face and the liquid fuel of injection is transported near spark plug by air movement.
The natural gas sprayed by gaseous-fuel injector 26 is mixed with the air entered from air inlet 32, and in compression process
Start with the premix uniform lean mixture filling combustion chamber 16 of gaseous fuel and air.It is directly sprayed from liquid fuel injector 20
Gasoline timing generation is penetrated in the latter portions of compression stroke, to form the dense gasoline or closeization having close to spark plug 18
Learn equivalent gasoline and air section layer inflation, by it is appropriate positioning come optimize liquid fuel injector 20 direction and
The geometry of top land and cylinder head.Burning starts from the spark ignition of layering gasoline and air mixture.In spark plug week
The gained combustion nucleus to be formed is enclosed, is then diffused into the gaseous mixture of uniform low density gas fuel and air.
Uniform thin or diluent gas fuel and air charge with hot EGR gas mixing by preheating, and mode is such as
It is lower described.During compression stroke, temperature would rise to the value close to TDC, the value low gaseous fuel and air mixing just
The autoignition temperature of object.Self-ignition point or more will be raised the temperature to by the raised temperature and pressure that Fuel Petroleum igniting generates, with
It lights all gas of combustion chamber automatically and carries out low-temperature burning.
Fig. 2 gives the various known valve opening diagrams for obtaining internal EGR.In all these valve opening diagrams
In, exhaust shows that air inlet is shown in phantom with solid line.
A indicates to be again turned on realization internal EGR by exhaust valve during induction stroke.
B indicates to be again turned on realization internal EGR by inlet valve during exhaust stroke.
C indicates that the closing of prerelease valve causes a high proportion of hot waste gas to retain in the combustion chamber.Intake valve is until TDC
It just opens, to prevent the residual gas of compression to be discharged to air inlet by intake valve.
D indicates to realize internal EGR by the big overlapping between the open hour of intake and exhaust valves.
Internal EGR can also be implemented with the known way in two stroke engine.
Claims (12)
1. a kind of design method for the dual fuel engine combustion chamber for improving gaseous fuel lean burn, is in a combustion chamber
Burning is passed through by the main gas charge including gaseous fuel and the mixed Daqu of air and is lighted the liquid being directly injected in combustion chamber
Fluid fuel causes the burning of the main gas charge, which is characterized in that the liquid fuel is gasoline, and sets in the combustion chamber
Spark plug is set to light gasoline.
2. the design method of the dual fuel engine combustion chamber according to claim 1 for improving gaseous fuel lean burn,
It is characterized in that, the gasoline is directly injected in combustion chamber, to generate layer inflation, gasoline is concentrated near spark plug.
3. the design side of the dual fuel engine combustion chamber according to claim 1 or 2 for improving gaseous fuel lean burn
Method, which is characterized in that the gaseous mixture of the gaseous fuel and air is less than the lean mixture of the gaseous mixture stoichiometric ratio.
4. the design method of the dual fuel engine combustion chamber according to claim 1 for improving gaseous fuel lean burn,
It is characterized in that, the air enters air intake duct by turbocharger or mechanical supercharger pressurization.
5. the dual fuel engine combustion chamber according to any one of claim 1 to 4 for improving gaseous fuel lean burn
Design method, which is characterized in that gaseous fuel makes the uniform premixing of gaseous fuel and air by being injected into air intake duct
Gaseous mixture enter combustion chamber.
6. the design method of the dual fuel engine combustion chamber according to claim 5 for improving gaseous fuel lean burn,
It is characterized in that, the kindling in order to promote homogeneous gas fuel and air mixture, just gasoline is only opened after plug ignition
Begin to burn, the hot waste gas from a upper burn cycle is kept in the combustion chamber or be reintroduced back to burning during subsequent circulation
Room, to increase the temperature of the gaseous mixture of gaseous fuel and air in subsequent circulation.
7. the design method of the dual fuel engine combustion chamber according to claim 6 for improving gaseous fuel lean burn,
It is characterized in that, realizing being reintroduced back to for the hot waste gas by the intake and exhaust valves for opening simultaneously combustion chamber.
8. the design of the dual fuel engine combustion chamber of improvement gaseous fuel lean burn according to claim 1 or 2 or 4
Method, which is characterized in that the gaseous fuel is selected from any one of natural gas, propane and methane or two or more.
9. the design of the dual fuel engine combustion chamber of improvement gaseous fuel lean burn according to claim 1 or 2 or 4
Method, which is characterized in that dual fuel engine is four-stroke engine.
10. according to the dual fuel engine combustion of improvement gaseous fuel lean burn described in claims requirement 1 or 2 or 4
Burn the design method of room, which is characterized in that dual fuel engine is two stroke engine.
11. a kind of combustion method of the dual fuel engine combustion chamber described in claim 1 for improving gaseous fuel lean burn,
It is characterized in that, the main gas charge of combustion chamber is the gaseous mixture of gaseous fuel and air, the main gas charge fills uniformly with combustion chamber,
The compression main gas charge, and gasoline being directly injected in combustion chamber at the end of compression, by spark ignitor gasoline and
The gaseous mixture of air charge, to light main gas charge.
12. combustion method according to claim 11, which is characterized in that direct injected petrol for generating in the combustion chamber
It is layered the mixture of gasoline and air charge, the gasoline first passes around spark plug when entering combustion chamber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910109065.2A CN110017213A (en) | 2019-02-03 | 2019-02-03 | Improve dual fuel engine combustion chamber and the combustion method of gaseous fuel lean burn |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910109065.2A CN110017213A (en) | 2019-02-03 | 2019-02-03 | Improve dual fuel engine combustion chamber and the combustion method of gaseous fuel lean burn |
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| Publication Number | Publication Date |
|---|---|
| CN110017213A true CN110017213A (en) | 2019-07-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910109065.2A Pending CN110017213A (en) | 2019-02-03 | 2019-02-03 | Improve dual fuel engine combustion chamber and the combustion method of gaseous fuel lean burn |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112780464A (en) * | 2021-03-04 | 2021-05-11 | 哈尔滨工程大学 | Dual-fuel engine of stepped spray hole structure oil injector and combustion organization method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6032617A (en) * | 1998-05-27 | 2000-03-07 | Caterpillar Inc. | Dual fuel engine which ignites a homogeneous mixture of gaseous fuel, air, and pilot fuel |
| CN104005871A (en) * | 2014-05-29 | 2014-08-27 | 天津大学 | Ignition and combustion control method of lean or diluted combustion of engine |
| CN105673281A (en) * | 2016-04-10 | 2016-06-15 | 北京工业大学 | Gas/liquid dual fuel in-cylinder/out-cylinder double-injection device and control method |
-
2019
- 2019-02-03 CN CN201910109065.2A patent/CN110017213A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6032617A (en) * | 1998-05-27 | 2000-03-07 | Caterpillar Inc. | Dual fuel engine which ignites a homogeneous mixture of gaseous fuel, air, and pilot fuel |
| CN104005871A (en) * | 2014-05-29 | 2014-08-27 | 天津大学 | Ignition and combustion control method of lean or diluted combustion of engine |
| CN105673281A (en) * | 2016-04-10 | 2016-06-15 | 北京工业大学 | Gas/liquid dual fuel in-cylinder/out-cylinder double-injection device and control method |
Non-Patent Citations (1)
| Title |
|---|
| 王利民等: "天然气-汽油双燃料发动机燃烧特性试验研究", 《内燃机工程》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112780464A (en) * | 2021-03-04 | 2021-05-11 | 哈尔滨工程大学 | Dual-fuel engine of stepped spray hole structure oil injector and combustion organization method thereof |
| CN112780464B (en) * | 2021-03-04 | 2022-06-17 | 哈尔滨工程大学 | Dual-fuel engine of stepped spray hole structure oil sprayer |
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| CB03 | Change of inventor or designer information |
Inventor after: Zhao Hua Inventor before: Zhao Hua Inventor before: Pei Yiqiang |
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Application publication date: 20190716 |
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