CN113266494B - System for recycling moisture in engine exhaust gas and reinjecting air inlet - Google Patents

System for recycling moisture in engine exhaust gas and reinjecting air inlet Download PDF

Info

Publication number
CN113266494B
CN113266494B CN202110594295.XA CN202110594295A CN113266494B CN 113266494 B CN113266494 B CN 113266494B CN 202110594295 A CN202110594295 A CN 202110594295A CN 113266494 B CN113266494 B CN 113266494B
Authority
CN
China
Prior art keywords
water
condensation separator
exhaust
valve
outlet
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.)
Active
Application number
CN202110594295.XA
Other languages
Chinese (zh)
Other versions
CN113266494A (en
Inventor
卢耀
冯立岩
夏雨
方源
张东
宋湄葭
曲文静
王自鑫
龚震
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.)
Dalian University of Technology
Original Assignee
Dalian University of 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 Dalian University of Technology filed Critical Dalian University of Technology
Priority to CN202110594295.XA priority Critical patent/CN113266494B/en
Publication of CN113266494A publication Critical patent/CN113266494A/en
Application granted granted Critical
Publication of CN113266494B publication Critical patent/CN113266494B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M25/00—Engine-pertinent apparatus for adding non-fuel substances or small quantities of secondary fuel to combustion-air, main fuel or fuel-air mixture
    • F02M25/022—Adding fuel and water emulsion, water or steam
    • F02M25/025—Adding water
    • F02M25/028—Adding water into the charge intakes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N5/00—Exhaust or silencing apparatus combined or associated with devices profiting by exhaust energy
    • F01N5/02—Exhaust or silencing apparatus combined or associated with devices profiting by exhaust energy the devices using heat
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M25/00—Engine-pertinent apparatus for adding non-fuel substances or small quantities of secondary fuel to combustion-air, main fuel or fuel-air mixture
    • F02M25/022—Adding fuel and water emulsion, water or steam
    • F02M25/0221—Details of the water supply system, e.g. pumps or arrangement of valves
    • F02M25/0222—Water recovery or storage
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M25/00—Engine-pertinent apparatus for adding non-fuel substances or small quantities of secondary fuel to combustion-air, main fuel or fuel-air mixture
    • F02M25/022—Adding fuel and water emulsion, water or steam
    • F02M25/0221—Details of the water supply system, e.g. pumps or arrangement of valves
    • F02M25/0224—Water treatment or cleaning
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/17—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories in relation to the intake system
    • F02M26/19—Means for improving the mixing of air and recirculated exhaust gases, e.g. venturis or multiple openings to the intake system
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
    • F02M26/29—Constructional details of the coolers, e.g. pipes, plates, ribs, insulation or materials
    • F02M26/30—Connections of coolers to other devices, e.g. to valves, heaters, compressors or filters; Coolers characterised by their location on the engine
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/36—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with means for adding fluids other than exhaust gas to the recirculation passage; with reformers
    • 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)
  • Water Supply & Treatment (AREA)
  • Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Exhaust-Gas Circulating Devices (AREA)

Abstract

The invention relates to a system for recovering moisture in exhaust gas of an engine and injecting the moisture into air, which comprises a heat exchanger, a coolant outlet bypass valve, a coolant outlet bypass pipeline, a first water vapor condensation separator, a second water vapor condensation separator, a recovery water tank, a water spraying assembly (water injector), exhaust aftertreatment, an exhaust bypass valve, a terminal exhaust pipe, an EGR valve, an EGR pipeline and an Electronic Control Unit (ECU); according to the invention, by recovering and removing water in the waste gas, the recovered condensate water is sprayed into the air inlet channel through the water injector, and is mixed with the fresh charge and then enters the combustion chamber of the engine, so that the combustion temperature in the cylinder is reduced, and the NOx emission and the risk of abnormal combustion are effectively reduced; meanwhile, the sustainability and the operation mileage of the air inlet water injection function of the engine are greatly increased, the water circulation utilization rate is improved, the condensed water accumulation in the EGR system is reduced, and the control precision, the stability and the service life of the EGR system are improved.

Description

System for recycling moisture in engine exhaust gas and reinjecting air inlet
Technical Field
The invention relates to the technical field of engines, in particular to a system for recycling moisture in engine exhaust gas and injecting the moisture into air.
Background
The concern of energy crisis forces the development of engine technology in the world towards high performance and low fuel consumption and even energy transformation, technologies such as supercharging, improving compression ratio and direct injection in cylinders are successfully applied, and fuels such as clean alternative energy hydrogen are also greatly developed in engines in recent years. However, the high performance and high power of the engine and the use of alternative fuels, especially hydrogen, also increase the risk of abnormal combustion of the engine, such as knocking and pre-ignition, due to the increased in-cylinder temperature, which is more severe at medium and high loads and extreme conditions. Moreover, nitrogen oxides (NOx) increase. It is well known that the serious emission problem of engines is one of the main contradictions of social production worldwide, and although China has started to implement the national six-emission regulations, the emission of NOx and the like from engines, particularly compression ignition engines, is still increasing year by year.
Exhaust Gas Recirculation (EGR) is one of the most effective technologies for reducing NOx emissions from the inside of an engine, and has been proven to reduce the risk of abnormal combustion and improve the efficiency of the engine, and is the main technical route for meeting the six emissions regulations of the state. However, water vapor is generated by burning of hydrocarbon fuel, and accounts for about 10-15% of the total mass of exhaust gas, the water vapor in the exhaust gas is gradually condensed into liquid water along with the reduction of temperature in the process of passing through an EGR cooler and mixing with fresh air, the liquid condensed water is continuously accumulated in a pipeline and the EGR cooler, if the water vapor is not discharged in time, the pressure drop is increased, the EGR flow and the steady-state control and the accuracy of an engine are influenced, and even parts of an EGR system are corroded and abraded to a certain extent. Furthermore, if hydrogen is used as the engine fuel, the mass fraction of water in the exhaust is as high as 25% when the excess air ratio is 1, much higher than conventional fuels, and therefore the problem of condensed water when EGR is used is more serious.
Intake water injection is also one of the most effective techniques for reducing engine NOx emissions and abnormal combustion. Because water has higher specific heat capacity, the water can be used as a diluent in the combustion process in the cylinder, so that the local highest combustion temperature is reduced, hot spots are reduced, the risk of abnormal combustion is reduced, and the generation of NOx is reduced. In fact, the intake air injection is optimized more effectively than EGR, and especially shows excellent effect under extreme conditions, and has little influence on the engine power performance. However, the use of intake water injection techniques creates an additional water demand on the engine, requiring a certain amount of water to be reserved for the engine and periodically filled due to consumption, which undoubtedly increases the burden on the engine system, while reducing the operating time of the intake water injection function to some extent. In addition, the use of intake water injection also results in a further increase in the water content of the engine exhaust. Patent CN201710527603.0 proposes an engine water injection system for recycling EGR condensed water, but only the water in the EGR exhaust gas is recycled, because the EGR exhaust gas usually only occupies a part of the exhaust gas and changes with the change of the engine operating condition and the demand for EGR, so the recycling water amount is not only limited but also continuously changes with the change of the EGR rate, sometimes even without EGR such as idling operating condition. In addition, without a condenser, condensate may accumulate in the EGR cooler and piping before the EGR mixer, affecting EGR control and corroding parts.
Disclosure of Invention
In view of the above problems, an object of the present invention is to provide a system for recovering moisture in exhaust gas of an engine and injecting the recovered condensed water into an intake duct through a water injector by recovering and removing moisture in the exhaust gas, and then injecting the recovered condensed water into an intake duct to be mixed with a fresh charge and then enter a combustion chamber of the engine, so as to reduce combustion temperature in a cylinder and effectively reduce NOx emission and risks of abnormal combustion; meanwhile, the sustainability and the operation mileage of the air inlet and water injection function of the engine are greatly increased, the water circulation utilization rate is improved, the condensed water accumulation in the EGR system is reduced, and the control precision, the stability and the service life of the EGR system are improved.
The technical scheme adopted by the invention is as follows:
the invention provides a system for recovering moisture in engine exhaust gas and injecting the moisture into intake air, which comprises a heat exchanger, a coolant outlet bypass valve, a coolant outlet bypass pipeline, a first water vapor condensation separator, a second water vapor condensation separator, a recovery water tank, a water spray assembly (water injector), exhaust aftertreatment, an exhaust bypass valve, a terminal exhaust pipe, an EGR valve, an EGR pipeline and an Electronic Control Unit (ECU);
the heat exchanger is provided with four passages of an inlet, an outlet, a cooling liquid inlet and a cooling liquid outlet; the engine exhaust pipeline is communicated with an inlet of a heat exchanger through exhaust aftertreatment, and an outlet of the heat exchanger is communicated with an exhaust gas inlet of the first water vapor condensation separator; a cooling liquid outlet of the heat exchanger is communicated with a cooling liquid outlet bypass pipeline through a cooling liquid outlet bypass valve; a part of the cooling liquid outlet bypass pipeline is arranged in the recovery water tank and used for heating the condensed water in the recovery water tank at the subzero temperature; the exhaust pipeline after exhaust aftertreatment is also communicated with a terminal exhaust pipe through an exhaust bypass valve;
the water outlet of the first water vapor condensation separator is communicated with the recovery water tank and is used for conveying and storing condensed water; the waste gas outlet of the first water vapor condensation separator is communicated with a terminal exhaust pipe;
the waste gas inlet of the second water vapor condensation separator is communicated with the waste gas outlet of the first water vapor condensation separator; the water outlet of the second water vapor condensation separator is communicated with the recovery water tank and is used for conveying and storing condensed water; an exhaust gas outlet of the second water vapor condensation separator is connected with one end of the EGR valve; the other end of the EGR valve is communicated with an engine air inlet pipeline through an EGR pipeline;
the water spraying assembly is connected between the recovery water tank and an air inlet channel of the engine;
and the cooling liquid outlet bypass valve, the exhaust bypass valve, the EGR valve and the water spray assembly are all connected with the electronic control unit ECU.
Further, the first water vapor condensation separator, the second water vapor condensation separator and the heat exchanger use the same cooling liquid.
Furthermore, the first water vapor condensation separator and the second water vapor condensation separator have the same structure and comprise condensation separator shells, cooling liquid covers, a water storage tank, tube plates, water vapor separation tubes, water baffles, condensation U-shaped tubes, cooling liquid inlets, cooling liquid outlets, waste gas inlets, waste gas outlets, water outlets and pressure valves; the water-vapor separation pipe is arranged in the middle of the inside of the shell of the condensation separator, the condensation U-shaped pipe is arranged on the outer side of the water-vapor separation pipe, and the water baffle is arranged at the bottom of the water-vapor separation pipe and used for condensing and separating water in waste gas; the water storage tank is arranged at the bottom of the shell of the condensation separator, and the water outlet is communicated with the bottom of the water storage tank through a pressure valve; the tube plate is arranged at the top in the condensation separator shell and used for fixing the condensation U-shaped tube and the water-vapor separation tube; the cooling liquid cover is arranged at the upper end of the condensation separator shell, and the cooling liquid inlet and the cooling liquid outlet are respectively arranged at the left side and the right side of the cooling liquid cover; the waste gas inlet is arranged on one side of the upper part of the condensation separator shell, and the waste gas outlet is arranged at the top of the water-vapor separation pipe.
Further, the water baffle is made of PCV materials.
Furthermore, the water spray assembly comprises a water supply valve, a filter, a water pump, a pressure regulating valve, a water rail, a backflow water pipe and a water injector; the water feeding valve is connected with a water feeding port at the bottom of the recovery water tank; the filter is connected with the water feeding valve; the water pump is connected with the filter; the inlet of the water rail is connected with a water pump to pump water to the water rail; the outlet of the water rail is connected with the lower end of the backflow water pipe through a pressure regulating valve, and the upper end of the backflow water pipe is communicated with the recovery water tank; the pressure regulating valve has the function of regulating the water pressure in the water rail and realizes constant-pressure injection; the water rail is communicated with the tail end of the water injector and provides water with certain pressure for the water injector; the water injector is arranged in an air inlet channel of the engine, supplies water through the recovery water tank, and injects water mist into the air inlet channel of the engine in a quantitative period at certain pressure and pulse width; the water supply valve, the water pump, the pressure regulating valve and the water injector are respectively connected with the electronic control unit ECU.
Furthermore, a liquid level meter and a temperature sensor are arranged in the recovery water tank and used for monitoring the liquid level height and the temperature of condensed water in the water tank; and the liquid level meter and the temperature sensor are respectively connected with the electronic control unit ECU.
Further, the height of the recovery water tank is lower than that of the first water vapor condensation separator and the second water vapor condensation separator.
Compared with the prior art, the invention has the following beneficial effects:
according to the invention, by recycling the condensed water in the engine exhaust gas, the sustainability of the air inlet water injection function of the engine and the water recycling rate are greatly increased, and enough water consumption can be ensured even if EGR is not carried out; through secondary condensation of the exhaust gas, the moisture in the EGR system is greatly reduced, and the control precision, stability and service life of the EGR system are improved; the EGR and intake water injection functions can be selectively and independently utilized in combination with different fuels, the working condition requirements of an engine and the like, the EGR rate, the water injection quantity, the water injection pressure and the like are controlled, and the two functions can also be simultaneously utilized to reduce the combustion temperature in the cylinder, improve the combustion in the cylinder, reduce the NOx emission and the risk of abnormal combustion and simultaneously avoid the performance reduction; the water temperature is heated at a lower environmental temperature by using the waste heat in the exhaust gas, so that the icing is avoided.
Drawings
FIG. 1 is a schematic overall sectional structure of the present invention;
fig. 2 is a schematic sectional structure view of the water vapor condensation separator in fig. 1.
Wherein, the reference numbers: 1-exhaust aftertreatment; 2-an exhaust pipeline; 3-coolant outlet bypass line; 4-an exhaust bypass valve; 5-a recovery water tank; 6-condensed water; 7-a heat exchanger; 8-coolant outlet bypass valve; 9-coolant outlet; 10-a first condensate recovery line; 11-a first water vapour condensation separator; 12-terminal exhaust pipe; 13-a second condensate recovery line; 14-a second moisture condensation separator; 15-an EGR valve; 16-an EGR line; 17-an electronic control unit ECU; 18-a return water pipe; 19-a pressure regulating valve; 20-an air intake line; 21-water rail; 22-a water injector; 23-air valve; 24-a piston; 25-a liquid level meter; 26-a temperature sensor; 27-water delivery valve; 28-a filter; 29-a water pump; 30-an exhaust gas inlet; 31-a tube sheet; 32-coolant hood; 33-coolant inlet; 34-an exhaust gas outlet; 35-a water-vapor separation tube; 36-coolant outlet; 37-condensation of U-tubes; 38-condensate separator shell; 39-exhaust flow direction; 40-a water baffle; 41-a water storage tank; 42-a pressure valve; 43-Water outlet.
Detailed Description
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
It should be noted that in the description of the present invention, the terms "upper", "lower", "top", "bottom", "one side", "the other side", "left", "right", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not mean that a device or an element must have a specific orientation, be configured and operated in a specific orientation.
Referring to fig. 1 and 2, a specific structure of an embodiment of a system for recovering moisture in engine exhaust gas and re-injecting the recovered moisture into intake air according to the present invention is shown.
The system comprises a heat exchanger 7, a coolant outlet bypass valve 8, a coolant outlet bypass pipeline 3, a first water vapor condensation separator 11, a second water vapor condensation separator 14, a recovery water tank 5, a water spray assembly, exhaust gas aftertreatment 1, an exhaust bypass valve 4, a terminal exhaust pipe 12, an EGR valve 15, an EGR pipeline 16 and an electronic control unit ECU 17.
The heat exchanger 7 is provided with four passages of an inlet, an outlet, a cooling liquid inlet and a cooling liquid outlet; the coolant inlet is not shown in the figure, and is not described because it is not connected to the system. The inlet of the heat exchanger 7 is connected with the engine exhaust pipeline 2 after the exhaust gas after-treatment 1 and receives the exhaust gas discharged from the engine; the outlet of the heat exchanger 7 is communicated with the waste gas inlet 30 of the first water vapor condensation separator 11, and the waste gas after being cooled to a certain degree is discharged; a cooling liquid outlet of the heat exchanger 7 is communicated with the cooling liquid outlet bypass pipeline 3 through a cooling liquid outlet bypass valve 8; one end of the cooling liquid outlet bypass pipeline 3 is directly communicated with a cooling liquid outlet 9 of the heat exchanger 7, and the other end of the cooling liquid outlet bypass pipeline is communicated with the cooling liquid outlet 9 through a cooling liquid outlet bypass valve 8; and a part of the coolant outlet bypass line 3 is arranged inside the recovery water tank 5, and is used for heating the recovery water tank by using waste heat of exhaust gas at a lower temperature so as to prevent the condensate water 6 in the tank from freezing.
The exhaust pipe 2 after the exhaust post-treatment 1 is also communicated with a terminal exhaust pipe 12 through an exhaust bypass valve 4, and is used for starting when more condensed water 6 exists in the recovery water tank 5, and stopping the condensation recovery process.
As shown in fig. 2, both the first moisture condensation separator 11 and the second moisture condensation separator 14 have the same structure, and use the same coolant as the heat exchanger 7; the first water vapor condensation separator 11 and the second water vapor condensation separator 14 both comprise a condensation separator shell 38, a cooling liquid cover 32, a water storage tank 41, a tube plate 31, a water vapor separation tube 35, a water baffle 40, a condensation U-shaped tube 37, a cooling liquid inlet 33, a cooling liquid outlet 36, an exhaust gas inlet 30, an exhaust gas outlet 34, a water outlet 43 and a pressure valve 42; the waste gas outlet 34 of the first water vapor condensation separator 11 is communicated with the terminal exhaust pipe 12, and the waste gas after the moisture is separated by the first condensation is discharged; the water outlet 43 of the first water vapor condensation separator 11 is communicated with the recovery water tank 5 through a first condensed water recovery pipeline 10 and is used for conveying and storing condensed water 6.
The waste gas inlet 30 of the second water vapor condensation separator 14 is communicated with the waste gas outlet 34 of the first water vapor condensation separator 11 and receives the waste gas with water separated by primary condensation; a water outlet 42 of the second water vapor condensation separator 14 is communicated with the recovery water tank 5 through a second condensed water recovery pipeline 13, so that moisture in the waste gas for recycling is further removed; the exhaust gas outlet 34 of the second water vapor condensation separator 14 is connected with an EGR pipeline 16 through an EGR valve 15, the EGR pipeline 16 is communicated with an air inlet pipeline 20 of the engine, and the dry air which is subjected to twice condensation and water separation is conveyed to the air inlet of the engine through the air inlet pipeline 20 to be mixed with fresh air.
The height of the recovery water tank 5 is lower than that of the first water vapor condensation separator 11 and the second water vapor condensation separator 14;
the water spraying component comprises a water supply valve 27, a filter 28, a water pump 29, a pressure regulating valve 19, a water rail 21, a water return pipe 18 and a water injector 22; the water feeding valve 27 is connected with a water feeding port at the bottom of the recovery water tank 5; one end of the filter 28 is connected with the water feeding valve 27, and the other end of the filter is connected with the water pump 29 and used for filtering impurities in water in the water tank; the inlet of the water rail 21 is connected with a water pump 29 and used for pumping water to the water rail 29; the outlet of the water rail 21 is connected with the lower end of a return water pipe 18 through a pressure regulating valve 19, and the upper end of the return water pipe 18 is communicated with a recovery water tank 5; the pressure regulating valve 19 has the function of regulating the water pressure in the water rail 21, so that the constant-pressure injection of the water injector 22 is realized; the water rail 21 is communicated with the tail end of the water injector 22 and is used for providing water with stable pressure for the water injector 22 of each cylinder; the water injector 22 is installed in the air inlet passage of the engine, supplies water through the recovery water tank 5, and injects water mist with a certain pressure and pulse width to a fixed amount and a fixed period in the air inlet passage of the engine.
A liquid level meter 25 and a temperature sensor 26 are also arranged in the recovery water tank 5 and are used for monitoring the water level height and the temperature of condensed water in the water tank; the recovery water tank 5 is communicated with the first condensate recovery pipeline 10, the second condensate recovery pipeline 13 and the return water pipe 18, and stores the recovered condensate in the waste gas and the return water of the water spray assembly.
The exhaust bypass valve 4, the coolant outlet bypass valve 8, the EGR valve 15, the pressure regulating valve 19, the water injector 22, the liquid level meter 25, the temperature sensor 26, the water feeding valve 27 and the water pump 29 are all connected with the electronic control unit ECU17, and signals from the sensors are received by the electronic control unit ECU17, so that the on-off of the valves, the size of valve ports, the pressure of the pressure regulating valve 19, the injection pulse width of the water injector 22 and the on-off control of the power supply of the water pump 29 are realized.
The control principle of the invention is as follows:
principle of water recovery
The exhaust gas of the engine contains a large amount of water vapor, the temperature of the exhaust gas after exhaust aftertreatment 1 is still high, and the exhaust gas enters a heat exchanger 7 after passing through an exhaust pipeline 2; the heat exchanger 7 is used for reducing the high-temperature waste gas to an acceptable certain range through the cooling effect of the cooling liquid, and the cooled waste gas enters the first water vapor condensation separator 11. As shown in fig. 2, the exhaust gas enters the first moisture separator condenser 11 through the exhaust gas inlet 30, rotates at a high speed between the moisture separator tube 35 and the condenser shell 38 in the exhaust gas flow direction 29, continuously shuttles between the condenser U-tubes 37, and finally exits the first moisture separator condenser 11 through the water deflector 40 into the moisture separator tube 35 toward the exhaust gas outlet 34. The moisture condensed in the exhaust gas adheres to the inner surface of the condensation separator case 38 by centrifugal force, and the water vapor not condensed is condensed on the outer surface of the condensation hairpin tube 37 by cooling action, further separating the moisture in the exhaust gas while passing through the water guard 40. The water baffle 40 is made of PCV materials, and the water-gas separation effect is good; the separated water attached to the inner surface of the condenser case 38, the outer surface of the condensation U-shaped pipe 37 and the water guard 40 flows into the reservoir 41, and when the water in the reservoir 41 is sufficient, the water pressure reaches a set value, the pressure valve 42 is automatically opened, and the water in the reservoir 41 is discharged to the recovery water tank 5 through the first condensate recovery pipe 10.
Most of the moisture in the exhaust gas after passing through the first moisture separator 11 is removed and recovered, and then discharged to the atmosphere through the exhaust gas outlet 34 and the final exhaust pipe 12. When the use of EGR is required, the ECU17 opens the EGR valve 15, and a part of the exhaust gas separated by the first condensation enters the intake air. In order to further separate the moisture in the exhaust gas to avoid water accumulation and corrosion and loss of the EGR system components, the exhaust gas enters the second moisture condensation separator 14 for a second moisture condensation separation. The condensed and separated water flows into the recovery water tank 5 through the second condensed water recovery pipeline 13. The exhaust gas from which moisture is separated by the second condensation is joined to the intake air through the EGR valve 15 and the EGR line 16.
Air inlet water injection control principle
And determining whether air inlet water injection is needed under different working conditions according to an advanced engine calibration result, and determining the optimal water injection pressure and water injection amount under different working conditions when air inlet water injection is carried out. In general, the water supply valve 27 is in a closed state, the power supply of the water pump 29 is in a power-off state, when the engine needs air intake and water injection, the electronic control unit ECU17 controls to open the water supply valve 27, the power supply of the water pump 29 is switched on, the condensed water 6 in the recovery water tank 5 flows through the filter 28 and the water pump 29 to enter the water rail 21, then is sprayed into the air inlet channel through the water injector 22 to be mixed with the intake air and then enters the engine cylinder, and the overflowing condensed water returns to the recovery water tank 5 through the backflow water pipe 18. The electronic control unit ECU17 adjusts the pressure value of the pressure regulating valve 19 under different working conditions according to the calibration result, so that the water pressure in the water rail 21 reaches a certain stable value, thereby controlling the pressure of air inlet water injection, and meanwhile, the electronic control unit ECU17 controls the opening pulse width of the water injector 22 according to the calibration result, thereby keeping the air inlet water injection amount under different working conditions constant.
The ECU17 will set three limits a, b and c for the water level in the recovery water tank 5. When the liquid level meter 25 detects that the water level is higher than the set limit value a, the water amount in the recovery water tank 5 is larger, the water level is higher, the electronic control unit ECU17 controls to open the exhaust bypass valve 4, so that the exhaust gas of the engine is directly discharged through the terminal exhaust pipe 12, and the recovery of the moisture in the exhaust gas by the first water vapor condensation separator 11 is stopped; when the liquid level meter 25 detects that the water level is lower than the set limit value b, the water amount in the recovery water tank 5 is less, the water level is lower, and the electronic control unit ECU17 controls to close the exhaust bypass valve 4, so that the exhaust gas of the engine passes through the heat exchanger 7 and the first water vapor condensation separator 11 to recover the moisture in the exhaust gas; when the liquid level meter 25 detects that the water level is lower than the set limit value c, the water quantity in the recovery water tank 5 is minimum, the water level is minimum, and the air inlet water injection requirement cannot be met, at the moment, the electronic control unit ECU17 carries out water level alarm through an external alarm device to prompt manual water injection.
Winter heating control principle of recovery water tank
The coolant after heat exchange in the heat exchanger 7 flows out through the coolant outlet 9, when the ambient temperature is below 0 ℃ and the engine is started for the first time, the temperature sensor 26 detects that the temperature of the condensed water 6 in the recovery water tank 5 is lower than or equal to the freezing point of water, the electronic control unit ECU17 opens the coolant outlet bypass valve 8 and cuts off the power supply of the water pump 29, so that the coolant after heat exchange heats the condensed water 6 solidified in the recovery water tank 5 through the coolant outlet bypass pipeline 3 to gradually melt the condensed water, and when the temperature of the condensed water 6 rises to a set temperature value which is enough to completely melt the ice in the recovery water tank 5 and the pipeline, the electronic control unit ECU17 closes the coolant outlet bypass valve 8 and stops heating the condensed water 6.
The above-mentioned embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solution of the present invention by those skilled in the art should fall within the protection scope defined by the claims of the present invention without departing from the spirit of the present invention.

Claims (6)

1. A system for recovering moisture in engine exhaust gas and reinjecting the moisture into intake air is characterized in that: the system comprises a heat exchanger, a coolant outlet bypass valve, a coolant outlet bypass pipeline, a first water vapor condensation separator, a second water vapor condensation separator, a recovery water tank, a water spray assembly, exhaust aftertreatment, an exhaust bypass valve, a terminal exhaust pipe, an EGR valve, an EGR pipeline and an Electronic Control Unit (ECU);
the heat exchanger is provided with four passages of an inlet, an outlet, a cooling liquid inlet and a cooling liquid outlet; the engine exhaust pipeline is communicated with an inlet of a heat exchanger through exhaust aftertreatment, and an outlet of the heat exchanger is communicated with an exhaust gas inlet of the first water vapor condensation separator; a cooling liquid outlet of the heat exchanger is communicated with a cooling liquid outlet bypass pipeline through a cooling liquid outlet bypass valve; a part of the cooling liquid outlet bypass pipeline is arranged in the recovery water tank and used for heating the condensed water in the recovery water tank at the subzero temperature; the exhaust pipeline after exhaust aftertreatment is also communicated with a terminal exhaust pipe through an exhaust bypass valve;
the water outlet of the first water vapor condensation separator is communicated with the recovery water tank and is used for conveying and storing condensed water; the waste gas outlet of the first water vapor condensation separator is communicated with a terminal exhaust pipe;
the waste gas inlet of the second water vapor condensation separator is communicated with the waste gas outlet of the first water vapor condensation separator; the water outlet of the second water vapor condensation separator is communicated with the recovery water tank and is used for conveying and storing condensed water; an exhaust gas outlet of the second water vapor condensation separator is connected with one end of the EGR valve; the other end of the EGR valve is communicated with an engine air inlet pipeline through an EGR pipeline;
the water spray assembly is connected between the recovery water tank and an air inlet channel of the engine;
the cooling liquid outlet bypass valve, the exhaust bypass valve, the EGR valve and the water spray assembly are all connected with an Electronic Control Unit (ECU);
the first water vapor condensation separator and the second water vapor condensation separator have the same structure and comprise condensation separator shells, cooling liquid cover caps, water storage pools, tube plates, water vapor separation tubes, water baffles, condensation U-shaped tubes, cooling liquid inlets, cooling liquid outlets, waste gas inlets, waste gas outlets, water outlets and pressure valves; the water-vapor separation pipe is arranged in the middle of the inside of the shell of the condensation separator, the condensation U-shaped pipe is arranged on the outer side of the water-vapor separation pipe, and the water baffle is arranged at the bottom of the water-vapor separation pipe and used for condensing and separating water in waste gas; the water storage tank is arranged at the bottom of the shell of the condensation separator, and the water outlet is communicated with the bottom of the water storage tank through a pressure valve; the tube plate is arranged at the top in the shell of the condensation separator and is used for fixing the condensation U-shaped tube and the water-vapor separation tube; the cooling liquid cover is arranged at the upper end of the condensation separator shell, and the cooling liquid inlet and the cooling liquid outlet are respectively arranged at the left side and the right side of the cooling liquid cover; the waste gas inlet is arranged on one side of the upper part of the condensation separator shell, and the waste gas outlet is arranged at the top of the water-vapor separation pipe.
2. The system for recovering moisture from engine exhaust for reinjection into intake air as claimed in claim 1, wherein: the first water vapor condensation separator, the second water vapor condensation separator and the heat exchanger use the same cooling fluid.
3. The system for recovering moisture from engine exhaust for reinjection into intake air as claimed in claim 1, wherein: the water baffle is made of PCV materials.
4. The system for recovering moisture from engine exhaust for reinjection into intake air as claimed in claim 1, wherein: the water spraying assembly comprises a water supply valve, a filter, a water pump, a pressure regulating valve, a water rail, a backflow water pipe and a water injector; the water feeding valve is connected with a water feeding port at the bottom of the recovery water tank; the filter is connected with the water feeding valve; the water pump is connected with the filter; the inlet of the water rail is connected with a water pump to pump water to the water rail; the outlet of the water rail is connected with the lower end of a backflow water pipe through a pressure regulating valve, and the upper end of the backflow water pipe is communicated with a recovery water tank; the pressure regulating valve has the function of regulating the water pressure in the water rail and realizes constant-pressure injection; the water rail is communicated with the tail end of the water injector and provides water with certain pressure to the water injector; the water injector is arranged in an air inlet channel of the engine, supplies water through the recovery water tank, and injects water mist into the air inlet channel of the engine in a quantitative period at certain pressure and pulse width; the water supply valve, the water pump, the pressure regulating valve and the water injector are respectively connected with the electronic control unit ECU.
5. The system for recovering moisture from engine exhaust for reinjection into intake air as claimed in claim 1, wherein: a liquid level meter and a temperature sensor are arranged in the recovery water tank and used for monitoring the liquid level height and the temperature of condensed water in the water tank; and the liquid level meter and the temperature sensor are respectively connected with the electronic control unit ECU.
6. The system for recovering moisture from engine exhaust for reinjection into intake air as claimed in claim 1, wherein: the height of the recovery water tank is lower than that of the first water vapor condensation separator and the second water vapor condensation separator.
CN202110594295.XA 2021-05-28 2021-05-28 System for recycling moisture in engine exhaust gas and reinjecting air inlet Active CN113266494B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110594295.XA CN113266494B (en) 2021-05-28 2021-05-28 System for recycling moisture in engine exhaust gas and reinjecting air inlet

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110594295.XA CN113266494B (en) 2021-05-28 2021-05-28 System for recycling moisture in engine exhaust gas and reinjecting air inlet

Publications (2)

Publication Number Publication Date
CN113266494A CN113266494A (en) 2021-08-17
CN113266494B true CN113266494B (en) 2022-08-26

Family

ID=77233494

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110594295.XA Active CN113266494B (en) 2021-05-28 2021-05-28 System for recycling moisture in engine exhaust gas and reinjecting air inlet

Country Status (1)

Country Link
CN (1) CN113266494B (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114135394A (en) * 2021-11-26 2022-03-04 中国北方发动机研究所(天津) High-power diesel engine waste water recycling injection system
CN114233442A (en) * 2021-12-24 2022-03-25 中国北方发动机研究所(天津) Engine with waste utilization function
CN114483334B (en) * 2022-01-25 2022-10-11 北京工业大学 Byproduct hydrogen internal combustion engine combining exhaust gas recirculation with water direct injection and method
CN114704351B (en) * 2022-02-28 2023-07-25 南方海洋科学与工程广东省实验室(广州) Device for recovering waste heat and water vapor of diesel engine to reduce emission of nitrogen oxides
CN115217675B (en) * 2022-03-01 2024-03-08 广州汽车集团股份有限公司 Engine water spraying system, control method of engine water spraying system and automobile
AT526089B1 (en) * 2022-04-26 2023-11-15 Avl List Gmbh HYDROGEN POWERED COMBUSTION ENGINE
CN115450752A (en) * 2022-09-15 2022-12-09 山东大学 Circulating system and method for realizing emission reduction and waste heat recovery of internal combustion engine
AT526664B1 (en) 2023-01-23 2024-06-15 Avl List Gmbh Hydrogen-powered internal combustion engine

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2926325A3 (en) * 2008-01-15 2009-07-17 Renault Sas Water injecting system for e.g. oil engine, of terrestrial transport vehicle, has injection unit i.e. water injector, introducing water removed from water reservoir by pump into cylinder of internal combustion engine
CN105863896A (en) * 2015-02-09 2016-08-17 现代自动车株式会社 Integrated EGR cooler
CN112377300A (en) * 2020-12-01 2021-02-19 广西玉柴机器股份有限公司 Method and system for inhibiting natural gas engine detonation combustion

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2926325A3 (en) * 2008-01-15 2009-07-17 Renault Sas Water injecting system for e.g. oil engine, of terrestrial transport vehicle, has injection unit i.e. water injector, introducing water removed from water reservoir by pump into cylinder of internal combustion engine
CN105863896A (en) * 2015-02-09 2016-08-17 现代自动车株式会社 Integrated EGR cooler
CN112377300A (en) * 2020-12-01 2021-02-19 广西玉柴机器股份有限公司 Method and system for inhibiting natural gas engine detonation combustion

Also Published As

Publication number Publication date
CN113266494A (en) 2021-08-17

Similar Documents

Publication Publication Date Title
CN113266494B (en) System for recycling moisture in engine exhaust gas and reinjecting air inlet
US20100242929A1 (en) Arrangement and method for the return of exhaust gases in a combustion engine
CN207554226U (en) Low pressure exhaust gas recycling ICS intercooler system with condensed water discharge function
CN111997710A (en) Engine crankcase ventilation system and method
JP4349166B2 (en) Intake passage of engine with EGR device
US8205602B2 (en) System and method of controlling an amount of condensation in an engine air intake system
CN107939560B (en) EGR cooler integrated with water removal device
US4844028A (en) Method for reducing the consumption of fuel of a heat engine which employs combustion of hydrocarbons, and for reducing atmospheric pollutants, and device for carrying out this method
CN212716817U (en) Engine and vehicle
CN217002090U (en) Intercooler, EGR system, engine and vehicle
CN109595095B (en) Marine diesel engine waste heat utilization and tail gas purification device
CN117052527A (en) Ammonia engine combined system and operation method
CN201943784U (en) Dewatering device of motor vehicle discharged tail gas
CN112377339B (en) Method and system for separating water vapor in EGR (exhaust gas recirculation) exhaust gas
CN213598093U (en) System for separating out water vapor in EGR (exhaust gas Recirculation) waste gas
US12085046B2 (en) EGR system and vehicle
CN213598068U (en) System for restraining natural gas engine knocking combustion
CN114508402A (en) Internal combustion engine, exhaust system and method for operating an internal combustion engine
CN112196703B (en) Dynamic control system and method for scavenging air oxygen concentration of marine low-speed dual-fuel main engine
CN212985336U (en) Closed crankcase ventilation system and engine
CN114233442A (en) Engine with waste utilization function
CN218439559U (en) Exhaust gas recirculation system
CN219139222U (en) EGR system and methanol engine
CN217152138U (en) EGR cooler of natural gas engine
CN115419523B (en) Hydrogen internal combustion engine control device based on mixed gas activity control

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
GR01 Patent grant
GR01 Patent grant