CN111472891A - Diesel ignition natural gas engine combustion system and control method thereof - Google Patents

Diesel ignition natural gas engine combustion system and control method thereof Download PDF

Info

Publication number
CN111472891A
CN111472891A CN202010336977.6A CN202010336977A CN111472891A CN 111472891 A CN111472891 A CN 111472891A CN 202010336977 A CN202010336977 A CN 202010336977A CN 111472891 A CN111472891 A CN 111472891A
Authority
CN
China
Prior art keywords
natural gas
engine
cylinder
diesel
air
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010336977.6A
Other languages
Chinese (zh)
Inventor
陈贵升
张敬贤
沈颖刚
李冰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kunming University of Science and Technology
Original Assignee
Kunming University of Science and Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kunming University of Science and Technology filed Critical Kunming University of Science and Technology
Priority to CN202010336977.6A priority Critical patent/CN111472891A/en
Publication of CN111472891A publication Critical patent/CN111472891A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • 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
    • F02D19/10—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 peculiar to compression-ignition engines in which the main fuel is gaseous
    • F02D19/105—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 peculiar to compression-ignition engines in which the main fuel is gaseous operating in a special mode, e.g. in a liquid fuel only mode for starting
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
    • F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
    • F02D13/0203—Variable control of intake and exhaust valves
    • 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
    • F02D19/0602—Control of components of the fuel supply system
    • F02D19/0607—Control of components of the fuel supply system to adjust the fuel mass or volume flow
    • F02D19/061—Control of components of the fuel supply system to adjust the fuel mass or volume flow by controlling fuel injectors
    • 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
    • F02D19/0647—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 the gaseous fuel being liquefied petroleum gas [LPG], liquefied natural gas [LNG], compressed natural gas [CNG] or dimethyl ether [DME]
    • 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
    • F02D19/0663—Details on the fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
    • 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
    • F02D19/0663—Details on the fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
    • F02D19/0673—Valves; Pressure or flow regulators; Mixers
    • F02D19/0678—Pressure or flow regulators therefor; Fuel metering valves therefor
    • 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
    • F02D19/0663—Details on the fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
    • F02D19/0684—High pressure fuel injection systems; Details on pumps, rails or the arrangement of valves in the fuel supply and return systems
    • 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
    • F02D19/0663—Details on the fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
    • F02D19/0686—Injectors
    • 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
    • F02D19/0663—Details on the fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
    • F02D19/0686—Injectors
    • F02D19/0689—Injectors for in-cylinder direct injection
    • 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
    • F02D19/0663—Details on the fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
    • F02D19/0697—Arrangement of fuel supply systems on engines or vehicle bodies; Components of the fuel supply system being combined with another device
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D23/00—Controlling engines characterised by their being supercharged
    • F02D23/02—Controlling engines characterised by their being supercharged the engines being of fuel-injection type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0002—Controlling intake air
    • F02D41/0007—Controlling intake air for control of turbo-charged or super-charged engines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/0047—Controlling exhaust gas recirculation [EGR]
    • F02D41/005—Controlling exhaust gas recirculation [EGR] according to engine operating conditions
    • F02D41/0052—Feedback control of engine parameters, e.g. for control of air/fuel ratio or intake air amount
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/0047—Controlling exhaust gas recirculation [EGR]
    • F02D41/005—Controlling exhaust gas recirculation [EGR] according to engine operating conditions
    • F02D41/0057—Specific combustion modes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/0047—Controlling exhaust gas recirculation [EGR]
    • F02D41/006—Controlling exhaust gas recirculation [EGR] using internal EGR
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/0047—Controlling exhaust gas recirculation [EGR]
    • F02D41/0065—Specific aspects of external EGR control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D21/00—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas
    • F02D21/06—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air
    • F02D21/08—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air the other gas being the exhaust gas of engine
    • F02D2021/083—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air the other gas being the exhaust gas of engine controlling exhaust gas recirculation electronically
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0002—Controlling intake air
    • F02D2041/001—Controlling intake air for engines with variable valve actuation
    • 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
    • Y02T10/12—Improving ICE efficiencies
    • 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

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)
  • Exhaust-Gas Circulating Devices (AREA)

Abstract

The invention relates to a diesel ignition natural gas engine combustion system and a control method thereof, wherein the diesel ignition natural gas engine combustion system comprises an engine main body, a diesel air inlet system, a natural gas inlet system, a variable cross-section turbocharger VGT, an exhaust gas recirculation system EGR, a variable valve regulator VVT, a dual-fuel ECU, a comprehensive ECU, a computer and a power supply; the EGR system comprises an EGR intercooler and an EGR valve. According to different operating conditions of the engine, the invention realizes accurate control of gas quantity by adjusting the gas channel and the in-cylinder jet valve jet strategy, forms mixed gas with different charging and layered states in the cylinder, couples thermodynamic state control on the basis, realizes stable ignition and controllable layered combustion under each operating condition by jointly controlling the variable valve regulator VVT and the exhaust gas recirculation system EGR and matching different equivalence ratios, further improves the natural gas substitution proportion of the dual-fuel engine, and realizes efficient and clean combustion in a wider operating condition operating range.

Description

Diesel ignition natural gas engine combustion system and control method thereof
Technical Field
The invention relates to a combustion system of a diesel ignition natural gas engine and a control method thereof, belonging to the technical field of combustion of internal combustion engines.
Technical Field
In the face of environmental pollution, increasingly stringent emission regulations are continuously driving internal combustion engines to move towards zero emission. Among many alternative fuels, natural gas is widely used in the fields of heavy trucks, urban buses, ships and the like because of abundant storage and low price. The main component of natural gas is methane (CH)4) The composite material has the characteristics of high octane number, low chemical activity, good anti-knock performance and the like, and is beneficial to improving the average effective pressure (BMEP) and the thermal efficiency (improving the compression ratio) of an engine; meanwhile, the natural gas has high H/C ratio, low sulfur content and no aromatic hydrocarbon, and is beneficial to reducing particulate matters and CO2Discharging; in addition, the natural gas laminar flame propagation speed is low, the combustible limit is wide, and the reduction of NOx and the expansion of the lean burn limit are facilitated. Therefore, natural gas as a low-carbon fuel is considered to have the functions of realizing efficient clean combustion of an engine and reducing CO2The high-quality alternative fuel. At present, the natural gas in the natural gas engine mainly adopts a Port Fuel Injection-PFI (Port Fuel Injection-PFI) mode. In the mode, under the working condition of small load, along with the increase of the substitution rate, the more uniform the mixed gas in the cylinder is, the lower the chemical activity and the activity layering of the mixed gas are, so that the combustion stability becomes worse and the fire is easy to break; under a large-load working condition, a large amount of homogeneous mixed gas is rapidly combusted, and measures such as reducing a compression ratio, delaying a combustion phase or diluting high-proportion EGR are generally adopted to avoid knocking so as to improve the substitution rate, but the heat efficiency is reduced. The formation of a large amount of homogeneous mixture in a cylinder is the root cause of poor stability of combustion at a small load and easy knocking at a large load (limited compression ratio) of a natural gas ignition and a high-substitution rate natural gas/diesel engine. Compared with air passage injection, the natural gas direct injection mode can improve the small-load combustion stability of the engine and expand the lean limitAnd suppresses the large load combustion rate. However, in the mode, the mixing time of the natural gas and the air is short, the mixed gas in the cylinder is not uniform, the concentration or the components of the mixed gas at the ignition moment are easy to generate cyclic variation due to a flow field and turbulence pulsation in the cylinder, and the penetration distance and the turbulent kinetic energy of the direct-injection gas-phase jet flow of the natural gas are obviously lower than those of liquid fuel, so that the combustion process in the cylinder is influenced.
Disclosure of Invention
The invention aims to provide a diesel ignition natural gas engine combustion system and a control method thereof, which are used for realizing the combustion of a diesel ignition natural gas engine under the coupling control of layering and thermodynamic states in a natural cylinder by means of a natural gas direct injection and air channel compound injection strategy, a variable valve technology and an exhaust gas recirculation strategy, solving the problems of poor low-load combustion stability under high substitution rate, high-load easy detonation under high compression ratio and the like of the existing natural gas air channel injection engine, further improving the natural gas substitution rate of a dual-fuel engine, and realizing efficient and clean combustion in a wider working condition operation range.
The technical scheme adopted by the invention is as follows: a combustion system of a diesel ignition natural gas engine comprises an engine body, a diesel air inlet system, a natural gas inlet system, a variable-section turbocharger VGT29, an exhaust gas recirculation system EGR, a variable valve regulator VVT12, a dual-fuel ECU13, a comprehensive ECU15, a computer 14 and a power supply 19; the EGR system includes an EGR intercooler 22, an EGR valve 25;
the engine main body comprises a cylinder head 32, a cylinder 33, a piston 34, a valve 11, the cylinder head 32, the cylinder 33 and the piston 34 form a combustion chamber, a natural gas intake system comprises a natural gas tank 1, a natural gas rail 5, a natural gas air passage injector 7 and a natural gas in-cylinder injector 8, an intake regulator 4 is arranged on an air passage between the natural gas tank 1 and the natural gas rail 5, two air outlets of the natural gas rail 5 are respectively connected with the natural gas air passage injector 7 and the natural gas in-cylinder injector 8, a natural gas pressure and temperature sensor 6 is arranged above the natural gas rail 5, the natural gas air passage injector 7 is arranged on an air passage 35 in front of the cylinder 33, the natural gas in-cylinder injector 8 is arranged on the top of the combustion chamber, an air filter 30 is connected with a variable-section turbocharger VGT29, one end of the variable-section turbocharger VGT, the other end of the exhaust passage is connected to an exhaust passage 36 behind the cylinder 33, a branch exhaust gas passage is arranged on the exhaust passage 36 behind the cylinder 33, a branch exhaust gas exhaust pipeline is connected with an EGR valve 25 through an EGR intercooler 22, the gas outlet end of the EGR valve 25 is connected with an air inlet passage 35 in front of the cylinder 33, the valve 11 is connected with a variable valve regulator VVT12, the air inlet regulator 4, the natural gas rail 5, the natural gas pressure and temperature sensor 6, the natural gas air passage injector 7 and the natural gas in-cylinder injector 8 are all connected with a dual-fuel ECU13, the variable valve regulator VVT12, the variable cross-section turbocharger VGT29 and the EGR valve 25 are all connected with a comprehensive ECU15, the dual-fuel ECU13 and the comprehensive ECU15 are all connected with the computer 14, and the dual-fuel ECU13 and the comprehensive.
Preferably, the natural gas intake system further comprises a shut-off valve 2 and a flow meter 3 connected with the dual-fuel ECU13, wherein the shut-off valve 2 and the flow meter 3 are installed on an air passage between the natural gas tank 1 and the intake regulator 4.
Preferably, the diesel oil supply system comprises an oil tank 18, a high-pressure oil pump 16, a diesel oil filter 17, a diesel oil high-pressure common rail 9 and a diesel oil injector 10, wherein the oil tank 18 is communicated with the diesel oil common rail 9 through the high-pressure oil pump 16 and the diesel oil filter 17, the oil outlet end of the diesel oil common rail 9 is connected with the diesel oil injector 10, the diesel oil injector 10 is installed at the top of a combustion chamber, and the high-pressure oil pump 16, the diesel oil filter 17, the diesel oil common rail 9 and the diesel oil injector 10 are all connected.
Preferably, a diesel rail pressure sensor connected with the integrated ECU15 is arranged on the diesel common rail 9.
Preferably, a valve position sensor is arranged on the variable valve regulator VVT12, an oxygen sensor is arranged in the air inlet channel 35, an exhaust gas temperature and pressure sensor is arranged in the exhaust channel 36, and the valve position sensor, the oxygen sensor, the exhaust gas temperature and pressure sensor are all connected with the integrated ECU 15.
Preferably, the engine body is externally connected with an eddy current dynamometer 24 for measuring power, an engine controller 20 for controlling the operation condition of the engine, an engine oil path and water path controller 21, a crankshaft position sensor 23 is installed at the crankshaft position of the engine, the eddy current dynamometer 24 is connected with the engine controller 20, and the crankshaft position sensor 23, the engine controller 20, the engine oil path and water path controller 21 are all connected with the comprehensive ECU 15.
Preferably, the tail end of the exhaust passage 36 is provided with a tail gas analyzer 27 and a smoke gas analyzer 28, and both the tail gas analyzer 27 and the smoke gas analyzer 28 are connected with the comprehensive ECU 15.
A control method of the combustion system of the diesel ignition natural gas engine,
in the middle and early stages of the compression stroke of the engine, natural gas and air layered mixed gas with different equivalence ratio gradient distribution is formed by adopting a natural gas in-cylinder direct injection mode or a direct injection and air passage composite injection mode, the ignition is triggered by virtue of an activated thermal atmosphere formed by low-temperature and high-temperature combustion reaction induction of a small amount of diesel injected near the compression top dead center, the multi-point controllable combustion of the layered mixed gas in the cylinder is realized, and on the basis, the coupled cooperative control is realized by combining with in-cylinder thermodynamic state regulation and control means of a variable-section turbocharger VGT29 and an EGR (exhaust gas recirculation) system;
when the engine is in a low load state, based on layered regulation and control of the concentration of mixed gas in the compression stroke and the early stage of the engine, the variable valve regulator VVT12 is combined, the variable valve regulator VVT12 is used for controlling the valve 11 to enable an intake valve to be opened secondarily in the exhaust stroke and an exhaust valve to be opened secondarily in the intake stroke, so that high-temperature waste gas is reversely sucked into the air inlet channel 35 and then enters the air cylinder 33, high-temperature waste gas in the exhaust channel 36 is reversely sucked into two internal EGR modes in the air cylinder 33 and is controlled by combining with an external EGR circulating system controlled by the EGR valve 25, and the variable-section turbocharger VGT29 is used for changing the supercharging conditions so as to regulate different equivalence ratios and realize control on the thermodynamic state in the air;
when the engine is under a large load, based on the layered regulation and control of the concentration of the mixed gas in the compression stroke and the early stage of the engine, the natural gas direct injection strategy is changed by controlling the air inlet regulator 4, the natural gas rail 5 and the natural gas in-cylinder injector 8, the valve 11 is controlled by the aid of the variable valve regulator VVT12 to realize an intake valve late closing strategy, and the intake valve late closing strategy and the variable valve regulator VVT12 realize coupling control. On the basis, the combustion is comprehensively optimized by matching with combustion control means such as intake air supercharging realized by a variable-section turbocharger VGT 29.
The invention has the beneficial effects that: according to the invention, the concentration of natural gas in the cylinder is flexibly regulated and controlled by optimizing a natural gas composite injection strategy, and the concentration of mixed gas in the cylinder is regulated and controlled in a layered manner by controlling the thermal stratification of an in-cylinder induced ignition activation space in cooperation with a diesel direct injection strategy; the control of the thermodynamic state in the cylinder is realized by applying a VVT technology and an EGR technology; the optimal matching of the equivalence ratio is realized through the application of a VGT technology; by combining the applications, the requirements of the engine under different load working conditions can be met, the combustion stability of the engine under low load under high substitution is improved, the knocking of the engine under high load under high compression ratio is inhibited, the natural gas substitution proportion of the dual-fuel engine is further improved, and efficient and clean combustion within a wider working condition operation range is realized.
Drawings
FIG. 1 is a schematic view of a combustion system of the present invention;
fig. 2 is an enlarged view of the piston, cylinder, and cylinder head portions of fig. 1.
The reference numbers in the figures are: 1-natural gas tank, 2-closing valve, 3-gas mass flowmeter, 4-air inlet regulator, 5-natural gas rail, 6-natural gas pressure and temperature sensor, 7-natural gas air flue injector, 8-natural gas in-cylinder injector, 9-diesel common rail, 10-diesel injector, 11-valve, 12-variable valve regulator VVT, 13-dual fuel ECU, 14-computer, 15-comprehensive ECU, 16-high pressure oil pump, 17-diesel filter, 18-oil tank, 19-battery, 20-engine controller, 21-engine oil circuit and water circuit controller, 22-EGR intercooler, 23-crankshaft position sensor, 24-vortex dynamometer, 25-EGR valve, 26-exhaust gas temperature and pressure sensor, 27-tail gas analyzer, 28-flue gas analyzer, 29-variable section turbocharger VGT, 30-air filter, 31-air intercooler, 32-cylinder cover, 33-cylinder, 34-piston, 35-air inlet channel and 36-exhaust channel.
Detailed Description
The invention is described in more detail below with reference to the figures and specific embodiments.
Example 1: as shown in fig. 1-2, a diesel ignition natural gas engine combustion system comprises an engine body, a diesel intake system, a natural gas intake system, a variable-section turbocharger VGT29, an exhaust gas recirculation system EGR, a variable valve regulator VVT12, a dual-fuel ECU13, a comprehensive ECU15, a computer 14, and a power supply 19; the EGR system includes an EGR intercooler 22, an EGR valve 25;
the engine main body comprises a cylinder head 32, a cylinder 33, a piston 34, a valve 11, the cylinder head 32, the cylinder 33 and the piston 34 form a combustion chamber, a natural gas intake system comprises a natural gas tank 1, a natural gas rail 5, a natural gas air passage injector 7 and a natural gas in-cylinder injector 8, an intake regulator 4 is arranged on an air passage between the natural gas tank 1 and the natural gas rail 5, two air outlets of the natural gas rail 5 are respectively connected with the natural gas air passage injector 7 and the natural gas in-cylinder injector 8, a natural gas pressure and temperature sensor 6 is arranged above the natural gas rail 5, the natural gas air passage injector 7 is arranged on an air passage 35 in front of the cylinder 33, the natural gas in-cylinder injector 8 is arranged on the top of the combustion chamber, an air filter 30 is connected with a variable-section turbocharger VGT29, one end of the variable-section turbocharger VGT, the other end of the exhaust passage is connected to an exhaust passage 36 behind the cylinder 33, a branch exhaust gas passage is arranged on the exhaust passage 36 behind the cylinder 33 and is connected with the EGR valve 25 through an EGR intercooler 22, the air outlet end of the EGR valve 25 is connected with an air inlet passage 35 in front of the cylinder 33, the valve 11 is connected with a variable valve regulator VVT12, the air inlet regulator 4, the natural gas rail 5, the natural gas pressure and temperature sensor 6, the natural gas air passage injector 7 and the natural gas in-cylinder injector 8 are all connected with a dual-fuel ECU13, the variable valve regulator VVT12, the variable cross-section turbocharger VGT29 and the EGR valve 25 are all connected with a comprehensive ECU15, the dual-fuel ECU13 and the comprehensive ECU15 are all connected with the computer 14, and the dual-fuel ECU13 and the comprehensive ECU15 are all connected.
Further, the natural gas intake system also comprises a closing valve 2 and a flow meter 3 which are connected with the dual-fuel ECU13, wherein the closing valve 2 and the flow meter 3 are arranged on an air passage between the natural gas tank 1 and the intake regulator 4. The dual-fuel ECU13 can control the natural gas intake amount well by closing the valve 2 and the flow meter 3.
Further, the diesel oil supply system comprises an oil tank 18, a high-pressure oil pump 16, a diesel oil filter 17, a diesel oil common rail 9 and a diesel oil injector 10, wherein the oil tank 18 is communicated with the diesel oil common rail 9 through the high-pressure oil pump 16 and the diesel oil filter 17, the oil outlet end of the diesel oil common rail 9 is connected with the diesel oil injector 10, the diesel oil injector 10 is installed at the top of the combustion chamber, and the high-pressure oil pump 16, the diesel oil filter 17, the diesel oil common rail 9 and the diesel oil injector 10 are all connected with a comprehensive.
Furthermore, a diesel rail pressure sensor connected with the integrated ECU15 is arranged on the diesel common rail 9.
Further, the variable valve regulator 12 is provided with a valve position sensor, the air inlet channel 35 is internally provided with an oxygen sensor, the exhaust channel 36 is internally provided with an exhaust gas temperature and pressure sensor, and the valve position sensor, the oxygen sensor, the exhaust gas temperature and pressure sensor are all connected with the comprehensive ECU 15.
Furthermore, the external part of the engine main body is connected with an eddy current dynamometer 24 for measuring power, an engine controller 20 for controlling the operation condition of the engine, an engine oil path and water path controller 21, a crankshaft position sensor 23 is installed at the crankshaft position of the engine, the eddy current dynamometer 24 is connected with the engine controller 20, and the crankshaft position sensor 23, the engine controller 20, the engine oil path and water path controller 21 are all connected with the comprehensive ECU 15. A crankshaft position sensor 23 is positioned at a crankshaft position for further monitoring engine operating conditions.
Further, the tail end of the exhaust passage 36 is provided with a tail gas analyzer 27 and a flue gas analyzer 28, and both the tail gas analyzer 27 and the flue gas analyzer 28 are connected with the comprehensive ECU 15. The ECU15 can clearly know whether the engine is fully combusted according to the exhaust gas analyzer 27 and the flue gas analyzer 28.
The engine body comprises a plurality of structures, the relevant content of the invention is described only by taking a single cylinder as a reference, the electric control unit integrated ECU15 and the dual-fuel ECU13 are powered by the battery 19, and each detection sensor is powered by the two ECUs 13 and 15. The engine has two sets of fuel supply systems. The first set of diesel injection supply system comprises a diesel injector 10 installed in a cylinder, the diesel injector 10 is connected to a diesel common rail 9 through an oil supply pipeline and then connected to an oil tank 18, a high-pressure oil pump 16 and a diesel filter 17 are installed on the oil supply pipeline, the injector 10, the high-pressure oil pump 16 and the diesel common rail 9 are all electrically connected with an engine control unit comprehensive ECU15, and a diesel injection strategy can be controlled through a computer 14. The second set of natural gas injection supply system comprises a natural gas in-cylinder injector 8 positioned in a cylinder and a natural gas air passage injector 7 positioned in an air inlet passage 35, wherein the two injectors are connected to a natural gas rail 5 through a gas pipeline and then connected to a natural gas tank 1, a closing valve 2 for controlling gas flow, an air inlet regulator 4 and a gas mass flow meter 3 for measuring flow are arranged on the gas pipeline, a natural gas pressure and temperature sensor 6 is also arranged on the natural gas rail 5, the natural gas pressure and temperature sensor 6, the natural gas air passage injector 7 and the natural gas in-cylinder injector 8 are electrically connected with a dual-fuel control unit ECU13, and a natural gas injection strategy can be changed through a computer 14. Air enters the air inlet system through the air filter 30, is pressurized under the action of the variable-section turbocharger 29, the temperature of the pressurized air is increased, and the pressurized air enters the intercooler 31 for cooling so as to improve the charge coefficient, wherein the opening degree of the variable-section turbocharger 29 can be controlled by the computer 14 through the comprehensive ECU 15. In response to the emission problem, an EGR system is added, and high-temperature exhaust gas may be cooled by the EGR intercooler 22 through a branch of the exhaust passage 36 and then returned to the intake system through the EGR valve 25 controlled by the control unit ECU 15. The variable valve regulator VVT12 is adopted to realize the in-cylinder composition layering, and the integrated ECU15 controls the variable valve regulator VVT12 to regulate the movement of the valve 11. In addition, in order to detect the emission characteristics of the system, a waste gas duct temperature and pressure sensor 26 is provided in the exhaust duct 36, and a tail gas analyzer 27 and a flue gas analyzer 28 are provided at the tail end.
The dual-fuel ECU13 is used for controlling two fuel supply and injection systems of diesel oil and natural gas and can complete automatic and smooth adjustment of the fuel supply and injection systems, the comprehensive ECU15 can realize control of the internal valve 11 of the variable valve regulator VVT12, control of the guide vane of the vortex section in the variable section turbocharger VGT29 and control of the opening degree of the EGR valve 25 and can effectively control the engine body, and the computer 14 is used for processing data, providing calculation, recording and analyzing.
A control method of a combustion system of a diesel ignition natural gas engine specifically comprises the following steps:
in the compression stroke and earlier stage of the engine, the natural gas adopts in-cylinder direct injection or direct injection and gas channel composite double injection by means of the natural gas channel injector 7 and the natural gas in-cylinder injector 8, the dual-fuel ECU13 of the electric control unit adjusts the composite injection proportion, injection timing, injection pressure and injection quantity according to the actual working condition of the engine to form natural gas and air layered mixed gas with different equivalence ratio gradient distribution, and the dual-fuel ECU13 is used for regulating and controlling the activation heat atmosphere (active base, flammable intermediate product and temperature) formed by injecting a small amount of diesel oil near a compression top dead center by the oil injector 10 to trigger ignition, so that the multi-point controllable combustion of the layered mixed gas in the cylinder is realized. The mode can not only form the advantage of stable multi-point ignition source induced ignition in the cylinder by means of a small amount of direct injection ignition diesel oil, but also flexibly play the dual advantages of improving the stability of low-load combustion under high substitution rate and inhibiting the combustion rate of high load under high compression ratio by direct injection layering synergistic air passage injection, is favorable for further improving the natural gas substitution rate of the dual-fuel engine, and realizes efficient and clean combustion in a wider working condition operation range.
When the engine is in a small load, based on the layered regulation and control of the concentration of the mixed gas in the middle and early stages of the compression stroke of the engine, the integrated ECU15 controls the variable valve regulator VVT12 of the engine to control the valve 11 to open the intake valve for the second time in the exhaust stroke and open the exhaust valve for the second time in the intake stroke, so that two internal EGR modes that high-temperature waste gas is sucked back into the air inlet passage 35 and then enters the cylinder 33 and high-temperature waste gas in the exhaust passage 36 is sucked back into the cylinder 33 are realized. The combined control of the EGR circulation system and the external EGR circulation system realized by controlling the opening degree of the EGR valve 25 by the integrated ECU15 can improve the combustion, performance and emission (reduce NOx) of the internal combustion engine under low-temperature combustion and low-load working conditions, and simultaneously, the temperature of working media in a cylinder is increased by heating high-temperature waste gas, so that the exhaust temperature can be increased, and the post-treatment of tail gas is facilitated. And the comprehensive ECU15 is matched to control the supercharging condition realized by the opening degree of the turbine blade in the variable-section turbocharger 29, so that the regulation and control of different air inflow, namely equivalent ratio, can be realized, and the higher in-cylinder temperature and oxygen concentration can be simultaneously maintained, thereby expanding the lower load limit of stable operation. The combination of the 3 technologies completes the control of the in-cylinder thermodynamic state (pressure, temperature and active heat stratification), and provides a way for further improving the small-load combustion stability of the engine and reducing the ignition quantity of diesel (improving the substitution rate).
When the engine is under heavy load, if a stratified mixture with a high concentration gradient is formed by only using a natural gas/diesel hybrid direct injection strategy to suppress knocking, particulate matter and an over-lean region are increased. Meanwhile, EGR is the most main internal purification means for reducing NOx at present, and the adoption of EGR can cause the reduction of the oxygen concentration in a cylinder and enhance the contribution degree of high-concentration layering of mixed gas to the generation of particulate matters; and the effect of inhibiting detonation is weakened by adopting proper layering of the mixed gas. Miller (Miller cycle) separates the actual compression ratio from the expansion ratio of the engine by closing the intake valve before and after bottom dead center (early and late closing), and the effective compression stroke is smaller than the expansion stroke. A large number of researches show that the Miller cycle based on late closing of the inlet valve can effectively control the thermal state (the highest pressure and the highest temperature in the cylinder) in the cylinder to inhibit the engine knocking and expand the application range of the compression ratio of the engine, and the Miller cycle is a high-efficiency thermal cycle for improving the thermal efficiency of a novel homogeneous or quasi-homogeneous internal combustion engine. Therefore, the natural gas direct injection technology is combined with the valve control technology, an intake valve late closing strategy (Miller thermodynamic cycle) is realized by means of a variable valve regulator VVT12 controlled by the integrated ECU15, the external intercooling EGR rate (NOx emission is reduced, combustion reaction rate is reduced and the engine knocks all the time) regulated and controlled by controlling the opening degree of the EGR valve 25 is comprehensively optimized by using combustion control means such as intake air pressurization (the unreasonable influence of intake valve late closing on intake air is weakened and the intercooling EGR rate application range is enlarged) and the like regulated by the variable-section turbocharger 29, so that the engine knocks can be restrained while high efficiency and low emission are realized, and a way is provided for improving the thermal efficiency by improving the compression.
While the present invention has been described in detail with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, and various changes can be made without departing from the spirit and scope of the present invention.

Claims (8)

1. A diesel ignition natural gas engine combustion system characterized in that: the system comprises an engine body, a diesel oil air inlet system, a natural gas air inlet system, a variable cross-section turbocharger VGT (29), an exhaust gas recirculation system EGR, a variable valve regulator VVT (12), a dual-fuel ECU (13), a comprehensive ECU (15), a computer (14) and a power supply (19); the EGR system comprises an EGR intercooler (22) and an EGR valve (25);
the engine main body comprises a cylinder cover (32), a cylinder (33), a piston (34), a valve (11), the cylinder cover (32), the cylinder (33) and the piston (34) form a combustion chamber, a natural gas inlet system comprises a natural gas tank (1), a natural gas rail (5), a natural gas air passage injector (7) and a natural gas in-cylinder injector (8), an air inlet regulator (4) is arranged on an air passage between the natural gas tank (1) and the natural gas rail (5), two air outlets of the natural gas rail (5) are respectively connected with the natural gas air passage injector (7) and the natural gas in-cylinder injector (8), a natural gas pressure and temperature sensor (6) is arranged above the natural gas rail (5), the natural gas air passage injector (7) is arranged on an air inlet passage (35) in front of the cylinder (33), the natural gas in-cylinder injector (8) is arranged at the top of the combustion chamber, an air filter (, one end of a variable cross-section turbocharger VGT (29) is connected with an air inlet channel (35) in front of an air cylinder (33) through an air intercooler (31), the other end of the variable cross-section turbocharger VGT is connected with an air outlet channel (36) behind the air cylinder (33), a branch waste gas exhaust channel is arranged on the air outlet channel (36) behind the air cylinder (33), the branch waste gas exhaust channel is connected with an EGR valve (25) through an EGR intercooler (22), the air outlet end of the EGR valve (25) is connected with the air inlet channel (35) in front of the air cylinder (33), a valve (11) is connected with a variable valve regulator VVT (12), an air inlet regulator (4), a natural gas rail (5), a natural gas pressure and temperature sensor (6), a natural gas air channel injector (7) and a natural gas in-cylinder injector (8) are all connected with a dual-fuel ECU (13), the variable valve regulator VVT (12), the variable cross-section turbocharger VGT (29), the dual-fuel ECU (13) and the comprehensive ECU (15) are both connected with the computer (14), and the dual-fuel ECU (13) and the comprehensive ECU (15) are both connected with the power supply (19).
2. A diesel-ignited natural gas engine combustion system as in claim 1, wherein: the natural gas intake system also comprises a closing valve (2) and a flow meter (3) which are connected with the dual-fuel ECU (13), wherein the closing valve (2) and the flow meter (3) are arranged on an air passage between the natural gas tank (1) and the intake regulator (4).
3. A diesel-ignited natural gas engine combustion system as in claim 1, wherein: the diesel oil supply system comprises an oil tank (18), a high-pressure oil pump (16), a diesel oil filter (17), a diesel oil common rail (9) and a diesel oil injector (10), wherein the oil tank (18) is communicated with the diesel oil common rail (9) through the high-pressure oil pump (16) and the diesel oil filter (17), the oil outlet end of the diesel oil common rail (9) is connected with the diesel oil injector (10), the diesel oil injector (10) is installed at the top of a combustion chamber, and the high-pressure oil pump (16), the diesel oil filter (17), the diesel oil common rail (9) and the diesel oil injector (10) are all connected.
4. A diesel-ignited natural gas engine combustion system as in claim 3, wherein: and a diesel rail pressure sensor connected with the comprehensive ECU (15) is arranged on the diesel common rail (9).
5. A diesel-ignited natural gas engine combustion system as in claim 1, wherein: the variable valve regulator VVT (12) is provided with a valve position sensor, an oxygen sensor is arranged in an air inlet channel (35), an exhaust gas temperature and pressure sensor (26) is arranged in an exhaust channel (36), and the valve position sensor, the oxygen sensor, the exhaust gas temperature and pressure sensor (26) are all connected with a comprehensive ECU (15).
6. A diesel-ignited natural gas engine combustion system as in claim 1, wherein: the engine comprises an engine body and is characterized in that an eddy current dynamometer (24) used for measuring power, an engine controller (20) controlling the operation condition of the engine, an engine oil path and a water path controller (21) are connected to the outside of the engine body, a crankshaft position sensor (23) is installed at the position of an engine crankshaft, the eddy current dynamometer (24) is connected with the engine controller (20), and the crankshaft position sensor (23), the engine controller (20), the engine oil path and the water path controller (21) are all connected with a comprehensive ECU (15).
7. A diesel-ignited natural gas engine combustion system as in claim 1, wherein: the tail end of the exhaust passage (36) is provided with a tail gas analyzer (27) and a smoke gas analyzer (28), and the tail gas analyzer (27) and the smoke gas analyzer (28) are both connected with the comprehensive ECU (15).
8. A control method of a diesel pilot natural gas engine combustion system as defined in any one of claims 1 to 7, characterized by:
in the middle and early stages of the compression stroke of the engine, natural gas and air layered mixed gas with different equivalence ratio gradient distributions is formed by adopting a natural gas in-cylinder direct injection or direct injection and air passage composite injection mode, and is ignited by triggering of an activated thermal atmosphere formed by low-temperature and high-temperature combustion reaction of a small amount of diesel injected near the compression top dead center, so that multipoint controllable combustion of the layered mixed gas in the cylinder is realized, and on the basis, the coupled cooperative control is realized by combining with a variable cross-section turbocharger VGT (29) and an in-cylinder thermodynamic state regulation and control means of an EGR (exhaust gas recirculation) system;
when the engine is in a low load state, based on layered regulation and control of the concentration of mixed gas in the middle and early stages of the compression stroke of the engine, the variable valve regulator VVT (12) is combined, the variable valve regulator VVT (12) is used for controlling the valve (11) to open an intake valve for the second time in the exhaust stroke and open an exhaust valve for the second time in the intake stroke, so that high-temperature waste gas is reversely sucked into an air inlet channel (35) and then enters an air cylinder (33), high-temperature waste gas in an exhaust channel (36) is reversely sucked into two internal EGR modes in the air cylinder (33) and then is jointly controlled with an external EGR circulating system controlled by an EGR valve (25), a variable-section turbocharger VGT (29) is used for changing the supercharging condition to adjust different equivalence ratios, and the control of the thermodynamic state in the cylinder is;
when the engine is under a large load, based on the layered regulation and control of the concentration of the mixed gas in the compression stroke and the early stage of the engine, a natural gas direct injection strategy is changed by controlling the air intake regulator (4), the natural gas rail (5) and the natural gas in-cylinder injector (8), an air intake valve late closing strategy is realized by controlling the air valve (11) through the variable valve regulator VVT (12), the air intake valve late closing strategy and the natural gas in-cylinder injector are coupled and controlled, and on the basis, the combustion is comprehensively optimized by matching with combustion control means such as air intake pressurization and the like realized by the variable-section turbocharger VGT (29).
CN202010336977.6A 2020-04-26 2020-04-26 Diesel ignition natural gas engine combustion system and control method thereof Pending CN111472891A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010336977.6A CN111472891A (en) 2020-04-26 2020-04-26 Diesel ignition natural gas engine combustion system and control method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010336977.6A CN111472891A (en) 2020-04-26 2020-04-26 Diesel ignition natural gas engine combustion system and control method thereof

Publications (1)

Publication Number Publication Date
CN111472891A true CN111472891A (en) 2020-07-31

Family

ID=71755676

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010336977.6A Pending CN111472891A (en) 2020-04-26 2020-04-26 Diesel ignition natural gas engine combustion system and control method thereof

Country Status (1)

Country Link
CN (1) CN111472891A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112128003A (en) * 2020-08-28 2020-12-25 江苏大学 Variable intake EGR device and method for dual-fuel engine for realizing in-cylinder oxygen concentration layering
CN112502877A (en) * 2020-11-23 2021-03-16 沪东重机有限公司 Integrated pilot oil supply system for dual-fuel diesel engine and working method thereof
WO2022047842A1 (en) * 2020-09-04 2022-03-10 常熟理工学院 Method for reducing content of polycyclic aromatic hydrocarbon substances in nano-scale particulate matter of diesel engine
CN114962094A (en) * 2022-05-09 2022-08-30 潍柴动力股份有限公司 Combustion system and control method thereof
CN115306599A (en) * 2022-08-15 2022-11-08 哈尔滨工程大学 VGT (variable geometry Fuel) controlled diesel ignition ammonia-hydrogen mixed fuel engine based on PLC (programmable logic controller) and control method
CN115370493A (en) * 2022-08-18 2022-11-22 山东大学 Gas supply pressure adjusting system and control method for natural gas engine

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104454194A (en) * 2013-09-25 2015-03-25 马自达汽车株式会社 Control device of compression-ignition engine
JP2015108297A (en) * 2013-12-03 2015-06-11 大阪瓦斯株式会社 Homogeneous charge compression ignition type engine and operation control method of the same
CN109386396A (en) * 2018-09-29 2019-02-26 哈尔滨工程大学 It is a kind of with high-low pressure gas injection and it is micro- spray diesel oil natural gas engine method for controlling combustion
CN110691898A (en) * 2017-05-31 2020-01-14 马自达汽车株式会社 Compression ignition engine

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104454194A (en) * 2013-09-25 2015-03-25 马自达汽车株式会社 Control device of compression-ignition engine
JP2015108297A (en) * 2013-12-03 2015-06-11 大阪瓦斯株式会社 Homogeneous charge compression ignition type engine and operation control method of the same
CN110691898A (en) * 2017-05-31 2020-01-14 马自达汽车株式会社 Compression ignition engine
CN109386396A (en) * 2018-09-29 2019-02-26 哈尔滨工程大学 It is a kind of with high-low pressure gas injection and it is micro- spray diesel oil natural gas engine method for controlling combustion

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
穆林: "基于共轨系统的柴油引燃式天然气发动机控制与优化研究", 《中国优秀硕士学位论文全文数据库工程科技Ⅱ辑》 *

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112128003A (en) * 2020-08-28 2020-12-25 江苏大学 Variable intake EGR device and method for dual-fuel engine for realizing in-cylinder oxygen concentration layering
WO2022047842A1 (en) * 2020-09-04 2022-03-10 常熟理工学院 Method for reducing content of polycyclic aromatic hydrocarbon substances in nano-scale particulate matter of diesel engine
CN112502877A (en) * 2020-11-23 2021-03-16 沪东重机有限公司 Integrated pilot oil supply system for dual-fuel diesel engine and working method thereof
CN114962094A (en) * 2022-05-09 2022-08-30 潍柴动力股份有限公司 Combustion system and control method thereof
CN114962094B (en) * 2022-05-09 2024-05-17 潍柴动力股份有限公司 Combustion system and control method thereof
CN115306599A (en) * 2022-08-15 2022-11-08 哈尔滨工程大学 VGT (variable geometry Fuel) controlled diesel ignition ammonia-hydrogen mixed fuel engine based on PLC (programmable logic controller) and control method
CN115370493A (en) * 2022-08-18 2022-11-22 山东大学 Gas supply pressure adjusting system and control method for natural gas engine
CN115370493B (en) * 2022-08-18 2023-11-03 山东大学 Natural gas engine air supply pressure adjusting system and control method

Similar Documents

Publication Publication Date Title
CN111472891A (en) Diesel ignition natural gas engine combustion system and control method thereof
Wang et al. Research of NOx reduction on a low-speed two-stroke marine diesel engine by using EGR (exhaust gas recirculation)–CB (cylinder bypass) and EGB (exhaust gas bypass)
Gürbüz et al. Evaluating the effects of boosting intake-air pressure on the performance and environmental-economic indicators in a hydrogen-fueled SI engine
CN110318891B (en) Multi-mode combustion organization method for natural gas/diesel dual-fuel engine
CN109538347B (en) Control method capable of realizing efficient clean compression ignition of gasoline in full working condition range
WO2014151478A1 (en) Multi-fuel flow systems and methods with dedicated exhaust gas recirculation
Wheeler et al. Increasing EGR Tolerance using High Tumble in a Modern GTDI Engine for Improved Low-Speed Performance
You et al. Experimental analysis of inert gases in EGR on engine power and combustion characteristics in a stoichiometric dual fuel heavy-duty natural gas engine ignited with diesel
CN109268170B (en) Composite gas supply dual-fuel engine system with double needle valve oil injector and combustion method
CN104989539A (en) Internal combustion engine for direct injection of double-gas fuel in cylinder under EGR condition and control method
CN109296469B (en) Reaction activity control-based dual-fuel engine combustion control method
CN110552805A (en) combustion control system and method for hydrogen repeated direct injection internal combustion engine
Zhang et al. EGR thermal and chemical effects on combustion and emission of diesel/natural gas dual-fuel engine
CN111305977A (en) Hydrogen natural gas full-proportion variable dual-fuel engine
CN116146361A (en) Combustion system and combustion method for hydrogen, diesel oil and ammonia ternary fuel engine
CN102226426A (en) Dual-fuel composite homogenous charge compression ignition combustion system based on activation heat atmosphere
Yan et al. A comparative study on the fuel economy improvement of a natural gas SI engine at the lean burn and the stoichiometric operation both with EGR under the premise of meeting EU6 emission legislation
CN209398491U (en) A kind of control system that can effectively expand gasoline compression ignition high-efficiency cleaning range of operation
GB2539906A (en) Fuel injection system for internal combustion engines
CN107061064A (en) A kind of equivalent combustion system and its control method based on air-fuel mixture enleanment
Veza et al. Strategies to achieve controlled auto-ignition (CAI) combustion: A review
CN111042955B (en) Engine system and combustion method
CN112196676A (en) Micro-injection ignition dual-fuel engine main diesel and natural gas coupled multi-injection combustion system
CN204961094U (en) Two gaseous fuel's of direct injection internal -combustion engine under EGR condition
CN108194207B (en) Variable compression ratio system of internal combustion engine and internal combustion engine

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication

Application publication date: 20200731

RJ01 Rejection of invention patent application after publication