![]() Internal combustion engine
专利摘要:
The invention relates to an internal combustion engine (1) having an exhaust gas recirculation system (2) having an exhaust gas recirculation line (19) between an exhaust system (3) and an intake system (4), designed in particular as a high - pressure exhaust gas recirculation system, with an air / EGR flow path (30 ), which, controlled by at least one valve (21), optionally with fresh air and / or recirculated exhaust gas can flow, wherein the inlet system (4) at least one with a Frischluftströmungsweg (9a, 9b, 9c) having flow-connected inlet header (16) from which at least one inlet duct (18) leading to at least one cylinder (Z) emanates. In order to reduce fuel consumption and / or emissions in all operating ranges in the simplest possible way and to enable a high and high charge dilution for all cylinders, it is provided that the air / EGR flow path (30) downstream of the electric compressor (22) into cylinder-selective feed channels (27) is divided, wherein per cylinder (Z) at least one feed channel (27) opens into an inlet channel (18). 公开号:AT512890A4 申请号:T50172/2013 申请日:2013-03-13 公开日:2013-12-15 发明作者:Paul Dr Kapus;Matthias Dipl Ing Fh Neubauer;Kurt Ing Prevedel 申请人:Avl List Gmbh; IPC主号:
专利说明:
Piinted: 14-03-2013 | E014: 1E 2013/50172 1 56560 The invention relates to an internal combustion engine with an exhaust gas recirculation line between an exhaust system and an intake system having - formed as a high-pressure exhaust gas recirculation system -Abgasrückführsystem with an arranged in an air / EGR flow path, electrically operated compressor, which, controlled by at least one valve, optionally with fresh air and / or recirculated exhaust gas can be flowed through, wherein the inlet system has at least one intake manifold, which is flow-connected to a fresh air flow path and from which at least one inlet duct leading to at least one cylinder emerges. From US 6,062,026 an internal combustion engine with an exhaust gas recirculation system is known, wherein in an air / EGR flow path (EGR = Exhaust Gas Recirculation), an electric compressor is arranged. The electric compressor can be bypassed via a by-pass valve having a bypass valve. In this case, a mixing valve is arranged in the region of a merger of the exhaust gas recirculation line and a fresh air flow path. The air / EGR flow path opens into the inlet header as the only inlet line. A cylinder-selective exhaust gas recirculation is therefore not possible. The mixing valve has the disadvantage that it must be designed for both high temperatures, as well as high exhaust gas / air flow rates, which adversely affects the manufacturing cost and cost. Since the mixing valve is traversed by the exhaust gas, it is exposed to heavy pollution, which has a very adverse effect on the life. From EP 0 911 502 Bl is an internal combustion engine with an exhaust gas recirculation system, wherein the exhaust gas recirculation line opens into a manifold, from which per cylinder in each case an inlet channel einmündender distribution channel emanates Thus, as equal and high charge dilution can be achieved for all cylinders. The object of the invention is the simplest possible way in an internal combustion engine of the type mentioned with the least possible effort to reduce fuel consumption and emissions in all operating areas and to allow a long service life. According to the invention this is achieved in that the air / EGR flow path downstream of the electric compressor in cylinder-selective feed channels Printed; 14-03-2013 EQU 10 2013/50172 2 with at least one feed channel leading into an inlet channel per cylinder. High-pressure exhaust gas recirculation systems are exhaust gas recirculation systems in which the exhaust gas recirculation line branches off from the exhaust system upstream of the turbine of the exhaust gas turbocharger and opens into the intake system downstream of the compressor of the exhaust gas turbocharger. Characterized in that the air / EGR flow path downstream of the electric compressor is divided into cylinder-selective feed channels, wherein at least one feed channel opens into an inlet channel per cylinder, in particular in high-pressure exhaust gas recirculation systems, a uniform distribution of the recirculated exhaust gas can be made possible. The cylinder-selective exhaust gas recirculation has the added benefit of avoiding contamination of parts of the intake system, such as intercoolers, intake manifolds or the like, and moreover, the transient behavior can be substantially improved. A particular advantage is obtained if at least one feed channel in the direction of the inlet main channel flow eccentrically opens into the inlet channel so that a tumble flow is generated in the combustion chamber or at least supported. The channel axis of the feed channel may include an angle of 0 ° +/- 30 ° with the central axis of the inlet channel in the region of the outlet opening. Effective support for the tumble flow in the cylinder is achieved when the outlet opening is located in the upper channel section farther from the cylinder. The mouth of at least one feed channel can be arranged, for example, in the initial region of the inlet channel, preferably in the region of the inlet collector, or in the end region of the inlet channel, preferably directly in front of the inlet channel into the combustion chamber. Due to the eccentric inflow, an asymmetric velocity distribution is generated in the inlet channel, whereby a tumble pulse is initiated upon the inflow into the cylinder. As a result, the charge movement in the combustion chamber can be generated or supported. Furthermore, directed EGR supply can also produce EGR stratification in the combustion chamber. 'Printed: 14-03-2013 £ 014 10 2013/50172 3 A particularly good charge movement can be generated if the inlet channel at least in sections has a parallel to the inlet channel main flow formed channel partition, preferably the channel partition is at least partially disposed in the region of the central axis and the upper third of the inlet channel, and wherein the channel partition the inlet Kana! The top third of the inlet channel is to be understood as the third which is furthest away from the cylinder or the cylinder head sealing plane. The inlet channel is thus divided by the channel partition into at least two channel sections, wherein the exhaust gas recirculation line opens into the upper channel section. The channel partition helps maintain the velocity distribution of inlet flow in the inlet channel until it enters the cylinder. In a further embodiment of the invention it is provided that a preferably designed as a simple control valve first valve in the exhaust gas recirculation line of the exhaust gas recirculation system, preferably upstream of the electrically operated compressor, and a second valve in a fresh air flow path of the intake system, preferably upstream of the electric compressor, is arranged. Thus, an error-prone and costly high-temperature resistant fresh air / EGR mixing valve can be dispensed with. A particularly simple variant of the invention provides that the second valve is formed as a check valve - preferably upstream of the bypass line -ausgebildet. This allows a particularly simple and accurate control of the EGR rates in all operating ranges of the internal combustion engine. A preferred embodiment of the invention provides that the second valve is formed by a simple control valve. This allows a particularly wide control range for exhaust gas and fresh air, as well as a mixture of exhaust gas and fresh air. The first valve can be designed for high exhaust gas temperatures, the second valve for the maximum intake air volume. Compared to the mixing valve known from the prior art, there are not only advantages in terms of costs, production, installation space and service life, but also in the control range. It is thus possible to regulate the first and the second valve completely independently of one another between a closed and a completely open position. Thus, between 100% fresh air and 100% EGR amount all intermediate mixing ratios are possible. The known from the prior art function of the mixing valve is thus divided into at least two valves. By dividing it into two valves, they can be better designed compared with a two-way mixing valve. The first valve arranged in the exhaust gas recirculation line can be designed for high temperature and relatively low throughput, while the second valve can be designed for lower temperature but higher throughput , When sizing the two valves thus no compromise needs to be made. On the other hand, oversizing to high temperatures and high throughputs is not required. Thus, the production cost can be significantly reduced. In addition to the advantage of a lower production effort, there is also less control effort than with a mixing valve. The electric supercharger can optionally be used to convey recirculated exhaust gas, fresh air, or a mixture of exhaust gas and fresh air. As a result, the transient behavior can be significantly improved. The electric compressor makes it possible to recycle high amounts of exhaust gas into the intake system even under unfavorable pressure conditions. Furthermore, the electric compressor can be used in addition to the compressor of the exhaust gas turbocharger as an additional charge stage for fresh air or a mixture of fresh air and recirculated exhaust gas. In a further embodiment of the invention can be provided that the electric compressor can be bypassed by a bypass line, wherein preferably in the bypass line, in particular designed as a check valve third valve is arranged. It can further be provided that the air / EGR flow path upstream of the division into the feed channels, preferably downstream of the electric compressor, is flow-connected to the fresh air flow path of the inlet system, preferably in the flow connection between the fresh air flow path and the air / EGR flow path a, preferably formed by a control valve, fourth valve is arranged. iPrlhted: 14 ^ 03-2013 £ 014 102013/50172 5 The flow connection makes it possible to decouple the charge movement supporting effect of the exhaust gas recirculation and set exhaust gas recirculation rate and charge motion support largely independently. The invention will be explained in more detail below with reference to FIGS. Show it: Fig. 1 to 4 internal combustion engines according to the invention in various embodiments Fig. 5 to 7 intake systems of internal combustion engines according to the invention in various embodiments. Functionally identical parts are provided in the embodiment variants with the same reference numerals. The engine 1 designed for a plurality of cylinders Z has an exhaust gas recirculation system 2 between an exhaust system 3 and an intake system 4. Reference numeral 5 denotes an exhaust-gas turbocharger whose exhaust-gas turbine 6 is arranged in the outlet branch 7 of the outlet system 3 and whose compressor 8 is arranged in the inlet branch 9 of the inlet system 4. Downstream of the turbine 6 of the exhaust gas turbocharger 5 exhaust gas purification devices 10 and muffler 11 are arranged. In the intake line 4, an air filter 12 is arranged upstream of the compressor 8 of the exhaust gas turbocharger 5, and a charge air cooler 13 is arranged downstream of the compressor 8. Reference number 14 denotes a lambda probe arranged downstream of the exhaust gas turbine 6 in the exhaust gas line 7, reference number 15 designates a boost pressure sensor arranged in the intake line 9 downstream of the compressor 8. Before entering the inlet string 9 in the intake manifold 16, a throttle valve 17 is arranged. From the intake manifold 16, cylinder-specific intake ports 18 lead to the individual cylinders Z. The exhaust gas recirculation system 2 has an exhaust gas recirculation line 19, which starts from the exhaust line 7 and leads to the intake system 4. In the 6th Exhaust gas recirculation line 19 is an exhaust gas recirculation cooler 20 and arranged as a control valve first valve 21 is arranged. Denoted by reference numeral 22 is an electric compressor which is positioned in an air / EGR flow path 30 between the exhaust gas recirculation system 2 and the intake system 4 so as to selectively deliver recirculated exhaust gas, fresh air, or a mixture of recirculated exhaust gas and fresh air. Fresh air side, in the fresh air flow path 9a, 9b upstream of the electric compressor 22, a second valve 23 is arranged, which may be designed as a control valve or as a check valve. The electric charger 22 can be bypassed on the fresh air side via a bypass line 24 emerging from the fresh air flow path 9a - the fresh air flow path 9c - into which a third valve 25 designed as a check valve is disposed. The exhaust gas recirculation system 2 is designed as a high-pressure exhaust gas recirculation system, wherein the exhaust gas recirculation line 19 branches off from the exhaust gas line 7 upstream of the exhaust gas turbine 6 and opens into the intake system 4 downstream of the compressor 8. In the region of the confluence of the air / EGR flow path 30 into the intake system 4, a distributor strip 26 with cylinder-selective feed channels 27 is arranged. The feed channels 27 lead either directly into inlet channels 18 leading to each cylinder Z (FIG. 5) or into the inlet header 16 (FIGS. 6 and 7), wherein the outlet openings 27a of the feed channels 27 are directed into the inlet channel main flow E of the inlet channels 18 are. The channel axis 27 'of the feed channel 27 includes in the region of its outlet opening 27a with the central axis 28 of the inlet channel 18 an angle α of 0 ° +/- 30 °. The outlet opening 27a of each feed channel 27 is arranged eccentrically with respect to the inlet channel 18, preferably in the upper channel section further spaced from the cylinder Z, whereby a targeted charge movement of the inlet flow in the cylinder Z is initiated, as is indicated in FIGS. 5 to 6. In particular, a tumble motion T in the cylinder space Z is amplified or caused. The charge movement can be further enhanced if the inlet channel 18 is divided into at least two sections by a channel partition wall 29 oriented in the region of the central axis 28 of the inlet channel 18 and oriented in inlet channel main flow E - an upper section 18a facing away from the cylinder the inflow of the recirculated exhaust gas A in FIGS. 5 to 7 into the upper portion 18 a of the inlet channel 18 Printed: 14-03-2013 £ 014: 102013/50172 7 takes place. When entering the cylinder Z thus different flow rates form, as indicated by the arrows S. This results in the cylinder space Z a pronounced tumble movement T. As can be seen in FIGS. 1 and 2, a further intercooler 31 is arranged downstream of the electric compressor 22 in the charge air line 30. By driving the first valve 21 and the second valve 23, the electric compressor 22 delivers either fresh air from the fresh air train 9a of the intake system 4, or recirculated exhaust gas from the exhaust gas recirculation line 19, or a mixture of recirculated exhaust gas and fresh air. The first valve 21 needs to be designed only for the maximum permissible recirculated exhaust gas quantity, but for high exhaust gas temperatures. The second valve 23, however, is thermally stressed little, but must be able to control large quantities of intake air. Thus, each of the two valves 21, 23 can be optimally designed for its respective intended use. Further, as shown in FIGS. 3 and 4, the air / EGR flow path 30 of the electric compressor 22 may be connected to the fresh air flow path 9c of the intake pipe 9 via a communication pipe 32, and a fourth control valve formed in the communication pipe 32 Valve 33 may be arranged. In the embodiment depicted in FIG. 3, the connecting line 32 between the throttle flap 17 and the inlet header 16 opens into the intake branch 9. 4 shows a variant in which the connecting line 32 is connected upstream of the throttle valve 17 to the fresh air flow path 9c of the intake branch 9. In this case, the fourth valve 33 can be dispensed with. The connecting line 32 makes it possible to decouple exhaust gas recirculation and charging movement from each other. In all embodiments, the electric compressor 22 serves both as a second charging stage, as well as a pump for recirculated exhaust gas. This makes it possible to carry out an exhaust gas recirculation with high exhaust gas recirculation rates even under unfavorable pressure conditions. In areas of poor response, the electric compressor 22 (which may be located either before or after the compressor 8 of the exhaust gas turbocharger) acts as a second charging stage that can close the so-called "turbo lag". In areas unfavorable iRrihted: 14-03-2013; E014; iO 2013/50172 8 Pressure ratio, the electric compressor 22 acts as a pump for recirculated exhaust gas. The required electrical energy is thereby preferably generated by an improved generator (e.g., a belt-starter-generator) in booms or phases in which power generation is positive from the energy point of view. Only in emergencies, the energy is generated at the time of consumption of the electric compressor 22. The illustrated variants with cylinder-selective exhaust gas recirculation have the advantage that excessive contamination of the intake system 4 can be avoided and the transient behavior can be improved. Furthermore, cylinder-selective supply in the cylinder head and the generation of charge movement is possible. In addition, a stratification of the recirculated exhaust gas in the combustion chamber can be generated via the directed supply. : T3iö3: 20T3
权利要求:
Claims (13) [1] 1. An internal combustion engine (1) having an exhaust gas recirculation system (2), which has an exhaust gas recirculation line (19) between an exhaust system (3) and an intake system (4) and is designed in particular as a high-pressure exhaust gas recirculation system an in an air / EGR flow path (30) arranged, electrically operated compressor (22), controlled by at least one valve (21), optionally with fresh air and / or recirculated exhaust gas flow bar, wherein the inlet system (4) at least an intake manifold (16) in fluid communication with a fresh air flow path (9a, 9b, 9c) from which at least one inlet duct (18) leading to at least one cylinder (Z) emanates, characterized in that the air / EGR flow path (30) is downstream of the electric compressor (22) is divided into cylinder-selective feed channels (27), wherein per cylinder (Z) at least one feed channel (27) into an inlet channel (18) opens. [2] 2. internal combustion engine (1) according to claim 1, characterized in that at least one feed channel (27) in the direction of the inlet channel main flow (E) eccentrically in the inlet channel (18) opens so that a tumble flow (T) in the cylinder ( Z) is generated or at least supported. [3] 3. internal combustion engine (1) according to claim 1 or 2, characterized in that the channel axis (27 ') of the feed channel (27) in the region of the outlet opening (27 a) with the central axis (28) of the inlet channel (18) an angle (a) of 0 ° +/- 30 °. [4] 4. Internal combustion engine (1) according to any one of claims 1 to 3, characterized in that the outlet opening (27 a) in a cylinder (Z) further spaced upper channel portion (18 a) of the inlet channel is arranged. [5] 5. internal combustion engine (1) according to one of claims 1 to 4, characterized in that the outlet opening (27a) at least one feed channel (27) in the initial region of the inlet channel (18), preferably in the region of the inlet collector (16) is arranged. iPrinted: 14-03-2013 IE015! 10 2Ö13 / 50172 10 [6] 6. Internal combustion engine (1) according to one of claims 1 to 4, characterized in that the outlet opening (27a) at least one feed channel (27) in the end region of the inlet channel (18) - preferably immediately before the mouth of the inlet channel (18) into the cylinder (Z) -ordered. [7] 7. internal combustion engine (1) according to one of claims 1 to 6, characterized in that the inlet channel (18) at least partially a parallel to the inlet channel main flow (E) formed channel partition wall (29), wherein preferably the channel partition (29) at least partially in the region of the central axis (28) of the inlet channel (18) is arranged, and wherein the channel partition wall (29) divides the inlet channel (18) in a cylinder facing away from the upper and a cylinder facing the lower channel portion (18a, 18b). [8] 8. Internal combustion engine (1) according to claim 7, characterized in that the channel partition wall (29) is arranged at least in sections in an upper third of the inlet channel (18). [9] 9. Internal combustion engine (1) according to one of claims 1 to 8, characterized in that a preferably designed as a simple control valve first valve (21) in the exhaust gas recirculation line (19) of the exhaust gas recirculation system (2), preferably upstream of the electrically operated compressor (22) , and a second valve (23) in a fresh air flow path (9a, 9b) of the inlet system (4), preferably upstream of the electric compressor (22), is arranged, wherein preferably the second valve (23) is designed as a simple control valve. [10] 10. internal combustion engine (1) according to one of claims 1 to 9, characterized in that the electric compressor (22) by a bypass line (24) is bypassable, wherein preferably in the bypass line (24) designed in particular as a check valve third valve (25 ) is arranged. [11] 11. Internal combustion engine (1) according to one of claims 1 to 10, characterized in that the air / EGR flow path (30) upstream of the division into the feed channels (27), preferably downstream of the iRrinted: 14-03-2013 ΪΕ015 | 10 2013/50172 11 electric compressor (22), with the fresh air flow path (9c) of the inlet system (4) is fluidly connected. [12] 12. Internal combustion engine (1) according to claim 11, characterized in that arranged in the flow connection (32) between the fresh air flow path (9c) and the air / EGR flow path (30), preferably formed by a control valve, fourth valve (33) is. 2013 03 [13] 13 Fu / Bt
类似技术:
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同族专利:
公开号 | 公开日 AT512890B1|2013-12-15| WO2014140150A1|2014-09-18| DE112014000280A5|2015-08-20|
引用文献:
公开号 | 申请日 | 公开日 | 申请人 | 专利标题 US6062026A|1997-05-30|2000-05-16|Turbodyne Systems, Inc.|Turbocharging systems for internal combustion engines| EP0911502B1|1997-10-21|2001-07-11|AVL List GmbH|Spark-ignited combustion engine| JP2005220822A|2004-02-05|2005-08-18|Toyota Motor Corp|Supercharging system for internal combustion engine| WO2007083131A1|2006-01-23|2007-07-26|Ricardo Uk Limited|Supercharged diesel engines|DE102016113316A1|2015-07-21|2017-01-26|Avl List Gmbh|Internal combustion engine| DE102015016207A1|2015-12-14|2017-06-14|GM Global Technology Operations LLC |Combustion engine arrangement| AT518431B1|2016-02-10|2017-10-15|Avl List Gmbh|METHOD FOR OPERATING AN INTERNAL COMBUSTION ENGINE| AT518400A4|2016-02-10|2017-10-15|Avl List Gmbh|INTERNAL COMBUSTION ENGINE WITH SEVERAL CYLINDERS| AT520737B1|2018-02-06|2019-07-15|Avl List Gbmh|Air intake system for a combustion engine|DE3025106C2|1980-07-02|1986-08-28|Suzuki Jidosha Kogyo K.K., Kami, Shizuoka|Intake system for an internal combustion engine working with a carburetor mixture metering device and exhaust gas recirculation| JPH0681719A|1992-08-31|1994-03-22|Hitachi Ltd|Intake device of internal combustion engine| FR2728939B1|1994-12-29|1997-02-21| JP4207695B2|2003-07-02|2009-01-14|マツダ株式会社|EGR control device for engine| FR2934645B1|2008-07-29|2010-08-13|Renault Sas|SUPERCHARGED INTERNAL COMBUSTION ENGINE EQUIPPED WITH A FLEXIBLE EXHAUST GAS RECIRCULATION CIRCUIT AND METHOD FOR ENGINE ACTUATION| US20100146968A1|2008-12-12|2010-06-17|Alexander Simpson|Emission system, apparatus, and method| US8181633B2|2008-12-17|2012-05-22|Aisin Seiki Kabushiki Kaisha|Intake manifold|DE102016219319A1|2016-10-05|2018-04-05|Bayerische Motoren Werke Aktiengesellschaft|Exhaust system of an engine| DE102017221747B3|2017-12-04|2019-02-28|Bayerische Motoren Werke Aktiengesellschaft|Internal combustion engine, motor vehicle with such and method for operating an internal combustion engine| AT523180B1|2019-12-16|2021-06-15|Avl List Gmbh|COMBUSTION MACHINE WITH MULTIPLE CYLINDERS|
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申请号 | 申请日 | 专利标题 ATA50172/2013A|AT512890B1|2013-03-13|2013-03-13|Internal combustion engine|ATA50172/2013A| AT512890B1|2013-03-13|2013-03-13|Internal combustion engine| DE112014000280.1T| DE112014000280A5|2013-03-13|2014-03-13|Internal combustion engine with several cylinders| PCT/EP2014/054918| WO2014140150A1|2013-03-13|2014-03-13|Internal combustion engine having several cylinders| 相关专利
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