WO2004111403A1 - Moteur a combustion interne avec douche d'introduction d'air secondaire - Google Patents

Moteur a combustion interne avec douche d'introduction d'air secondaire Download PDF

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Publication number
WO2004111403A1
WO2004111403A1 PCT/EP2004/006412 EP2004006412W WO2004111403A1 WO 2004111403 A1 WO2004111403 A1 WO 2004111403A1 EP 2004006412 W EP2004006412 W EP 2004006412W WO 2004111403 A1 WO2004111403 A1 WO 2004111403A1
Authority
WO
WIPO (PCT)
Prior art keywords
secondary air
internal combustion
combustion engine
guide element
air guide
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.)
Ceased
Application number
PCT/EP2004/006412
Other languages
German (de)
English (en)
Inventor
Hans-Karl Weining
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.)
Mercedes Benz Group AG
Original Assignee
DaimlerChrysler AG
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 DaimlerChrysler AG filed Critical DaimlerChrysler AG
Publication of WO2004111403A1 publication Critical patent/WO2004111403A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F1/00—Cylinders; Cylinder heads 
    • F02F1/24—Cylinder heads
    • F02F1/42—Shape or arrangement of intake or exhaust channels in cylinder heads
    • F02F1/4264—Shape or arrangement of intake or exhaust channels in cylinder heads of exhaust channels
    • F02F1/4271—Shape or arrangement of intake or exhaust channels in cylinder heads of exhaust channels with an exhaust liner
    • 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
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
    • 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
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
    • F01N3/0828—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents characterised by the absorbed or adsorbed substances
    • F01N3/0835—Hydrocarbons
    • 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
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
    • F01N3/30—Arrangements for supply of additional air
    • F01N3/34—Arrangements for supply of additional air using air conduits or jet air pumps, e.g. near the engine exhaust port
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F1/00—Cylinders; Cylinder heads 
    • F02F1/24—Cylinder heads
    • F02F1/42—Shape or arrangement of intake or exhaust channels in cylinder heads
    • F02F1/4264—Shape or arrangement of intake or exhaust channels in cylinder heads of exhaust channels
    • 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
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
    • 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

Definitions

  • the invention relates to an internal combustion engine for a motor vehicle with a combustion chamber, to which an inlet channel for supplying fuel gas, an outlet channel for discharging combustion products and a fuel supply unit for supplying liquid fuel are assigned.
  • the object of the invention is to provide an internal combustion engine for a motor vehicle with as simple as possible means of reduced emissions of unburned or partially burned fuel components, especially during cold start operation.
  • the internal combustion engine according to the invention is characterized by a secondary air guiding element arranged in the outlet duct to form a secondary air duct running at least partially parallel to the outlet duct.
  • a secondary air guiding element arranged in the outlet duct to form a secondary air duct running at least partially parallel to the outlet duct.
  • additional fresh air or, if necessary, recirculated exhaust gas can also be introduced into the outlet duct and mixed with the exhaust gas, the hot exhaust gas being able to be cooled on the one hand and being chemically converted on the other hand by means of the secondary air.
  • components arranged in the cylinder head can also be effectively cooled with the secondary air.
  • the secondary air duct is provided in order to bring secondary air as close as possible to a corresponding outlet valve or its valve seat.
  • the secondary air guide element is designed as a separate, preferably perforated insert element and is introduced into the outlet duct in such a way that the secondary air duct is formed behind the insert element.
  • the insert element thus separates the exhaust gas flowing in the direction of the exhaust tract (outward) from the fresh air flowing in the direction of the valve seat (inward). Air can be supplied to the secondary air duct, for example, via a bore in the cylinder head.
  • the secondary air guiding element is a multiplicity of perforations, in particular has round and / or oval openings through which a wide range of secondary air can be mixed with the exhaust gas. This enables a kind of secondary air shower with good mixing properties.
  • the secondary air guide element is cylindrical and is introduced into the outlet channel in such a way that a secondary air channel with an annular cross section is formed between the secondary air guide element and the outlet channel wall.
  • the exhaust gas flow can be completely encased in the secondary air duct. Secondary air and / or recirculated exhaust gas can be supplied to the exhaust gas flow on all sides.
  • flow guide elements and / or turbulence promoters are arranged on the secondary air guide element. This results in a particularly good mixing of secondary air and exhaust gas.
  • a constriction for the exhaust gas flow of the internal combustion engine is produced in the outlet duct with the aid of the secondary air guide element.
  • a constriction there is an increased flow velocity of the exhaust gas flow and a reduced static pressure, so that fresh air can be sucked into the exhaust gas flow from the secondary air duct.
  • Fig. 1 is a schematic representation of a longitudinal section through an outlet duct with a first embodiment of a secondary air guide element according to the invention
  • Fig. 2 is a schematic representation corresponding to FIG. 1 with a second embodiment of the secondary air guide element according to the invention.
  • An internal combustion engine 1 for a motor vehicle has a cylinder head 1a, which together with a movable piston serves to limit a preferably cylindrical combustion chamber 2 in an engine block of the internal combustion engine.
  • the internal combustion engine can be operated using the diesel or the Otto method.
  • an inlet channel for supplying fuel gas in the form of combustion air into the combustion chamber and an outlet channel 3 for removing combustion products from the combustion chamber are provided in the cylinder head Ia.
  • the exhaust port 3 is delimited by a wall 1b on the part of the cylinder head.
  • a fuel supply unit for supplying liquid fuel to the combustion chamber 2 is also provided; this is preferably an inlet duct or a direct injection system with corresponding nozzles or injectors and at least one delivery unit (fuel pump). Liquid hydrocarbons, e.g. Petrol or diesel fuel used.
  • FIG. 1 shows a section through the cylinder head 1 a, which runs in a direction parallel to the longitudinal axis of the exhaust port 3.
  • a first embodiment of a secondary air guiding element 6 is shown schematically therein.
  • the secondary air guide element 6 is inserted in the outlet duct 3 in the form of an insert element.
  • the secondary air guide element 6 is designed as a dimensionally stable sleeve which is adapted to the contour of the outlet channel 3 and which preferably has perforations 6a, 6b distributed over part of its surface.
  • the secondary air guiding element 6 is not a separate component, but rather made in one piece with the cylinder head 1.
  • an intermediate space 7 is formed, which is connected via the perforations 6a to the interior 10 of the insert element and which can be supplied with secondary air via a bore 4 in the cylinder head Ia.
  • the intermediate space 7 thus serves as a secondary air duct running parallel to the exhaust gas outlet duct 3, 10.
  • gas for example in the form of fresh air, recirculated exhaust gas or a mixture thereof, is supplied to the secondary air duct 7 by means of a pump or a similar delivery device via the bore 4 at intervals or continuously. As indicated by the arrows 5, this secondary air emerges from the secondary air duct 7 through the perforations 6a, 6b at various, structurally definable points. It is then added to the exhaust gas stream leaving the combustion chamber 2.
  • the perforations 6a, 6b are to be dimensioned as required and can have any number and opening cross sections.
  • the perforations 6a, 6b are preferably designed as a plurality of round or oval openings 6a in the insert element 6.
  • an opening 6b can be provided on an end face of the secondary air guiding element 6 facing the combustion chamber 2. Such an opening is formed particularly simply by a gap between the secondary air guide element 6 and the wall 1b. Such a gap is preferably circular in design.
  • FIG. 2 A further modified embodiment is shown in FIG. 2.
  • the secondary air guide element 6 is provided with a nozzle-like shape.
  • a constriction 6c is provided, at which the flow velocity of the exhaust gas increases and the static pressure is reduced particularly effectively.
  • a plurality of perforations 6a are preferably made in a ring shape at the narrow point 6c in the secondary air guiding element 6, so that the secondary air with the aid of a particularly low overpressure potential in the direction of the arrows 5 from a feed 4 into the secondary air duct 7 and from there into the inner region 10 of the exhaust gas outlet duct can be brought.
  • the secondary air duct runs at least in sections parallel to the exhaust gas outlet duct, which is thereby also insulated from the outside of the secondary air duct.
  • the secondary air flow can be mixed in the described manner with particularly simple means and particularly effectively and specifically to the exhaust gas flow.
  • fuel components expelled partially or unburned from a combustion chamber of the internal combustion engine can be reacted with the aid of the secondary air, i.e. implement chemically.
  • the aid of the secondary air i.e. implement chemically.
  • fuel emissions are reacted to and effectively eliminated, particularly when the internal combustion engine is cold started.
  • An internal combustion engine with cold start behavior that is significantly improved with respect to fuel or hydrocarbon emissions is provided.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Exhaust Gas After Treatment (AREA)

Abstract

L'invention concerne un moteur à combustion interne pour véhicule automobile, qui comprend une chambre de combustion (2) à laquelle sont associés un orifice d'admission, pour l'introduction de gaz combustible, un canal d'échappement (3) pour l'évacuation des produits de combustion, et une unité d'alimentation en carburant pour l'amenée de carburant liquide. Selon l'invention, un élément d'adsorption et/ou un élément d'absorption servant au stockage intermédiaire du carburant non brûlé ou brûlé partiellement est monté dans le canal d'échappement (3) du moteur à combustion interne. En particulier, un élément rapporté perforé et/ou une couche d'adsorption et/ou une couche d'absorption sont placés dans le canal d'échappement. Cette invention trouve des applications dans les véhicules automobiles, notamment dans les voitures particulières.
PCT/EP2004/006412 2003-06-18 2004-06-15 Moteur a combustion interne avec douche d'introduction d'air secondaire Ceased WO2004111403A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10327305.0 2003-06-18
DE10327305A DE10327305A1 (de) 2003-06-18 2003-06-18 Brennkraftmaschine mit Sekundärluftbrause

Publications (1)

Publication Number Publication Date
WO2004111403A1 true WO2004111403A1 (fr) 2004-12-23

Family

ID=33495095

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2004/006412 Ceased WO2004111403A1 (fr) 2003-06-18 2004-06-15 Moteur a combustion interne avec douche d'introduction d'air secondaire

Country Status (2)

Country Link
DE (1) DE10327305A1 (fr)
WO (1) WO2004111403A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8464519B2 (en) 2009-01-28 2013-06-18 Friedrich Boysen Gmbh & Co. Kg Secondary air system
WO2016106994A1 (fr) * 2014-12-31 2016-07-07 安徽江淮汽车股份有限公司 Tuyau d'injection d'air secondaire et système d'injection d'air secondaire

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT505765B1 (de) 2007-09-20 2009-04-15 Kirchberger Roland Dipl Ing Dr Verbrennungskraftmaschine
DE102008033750A1 (de) 2008-07-18 2010-01-21 Audi Ag Verfahren zum Betreiben eines Verbrennungsmotors sowie Kraftfahrzeug

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4096690A (en) * 1976-12-27 1978-06-27 Ford Motor Company Louvered exhaust port liner
EP0640752A1 (fr) * 1993-08-27 1995-03-01 Yamaha Hatsudoki Kabushiki Kaisha Dispositif d'échappement pour un moteur à combustion interne
WO1996023133A1 (fr) * 1995-01-25 1996-08-01 Pfefferle William C Procede catalytique
DE19938359A1 (de) * 1999-08-13 2001-02-22 Audi Ag Abgaskrümmer für eine mehrzylindrige Brennkraftmaschine mit Sekundärluftzufuhr
DE10005909A1 (de) * 2000-02-10 2001-08-16 Audi Ag Vorrichtung zum Regenerieren, Heizen und Entschwefeln des NOx-Speicherkatalysators einer Brennkraftmaschine

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3468124A (en) * 1967-04-25 1969-09-23 Mykola Hraboweckyj Method and apparatus for consuming combustible gases in engine exhaust gases
DE4118848C2 (de) * 1991-06-07 2000-02-24 Audi Ag Verfahren zum Betreiben einer Brennkraftmaschine
DE4209684A1 (de) * 1992-03-25 1993-09-30 Porsche Ag Einrichtung zur Beeinflussung der Strömung in Gaswechselkanälen einer Brennkraftmaschine
US5419125A (en) * 1992-09-21 1995-05-30 Calsonic Corporation Exhaust-gas recombustion system
DE10215914B4 (de) * 2002-04-11 2009-01-02 Daimler Ag Ventilgesteuerte Brennkraftmaschine

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4096690A (en) * 1976-12-27 1978-06-27 Ford Motor Company Louvered exhaust port liner
EP0640752A1 (fr) * 1993-08-27 1995-03-01 Yamaha Hatsudoki Kabushiki Kaisha Dispositif d'échappement pour un moteur à combustion interne
WO1996023133A1 (fr) * 1995-01-25 1996-08-01 Pfefferle William C Procede catalytique
DE19938359A1 (de) * 1999-08-13 2001-02-22 Audi Ag Abgaskrümmer für eine mehrzylindrige Brennkraftmaschine mit Sekundärluftzufuhr
DE10005909A1 (de) * 2000-02-10 2001-08-16 Audi Ag Vorrichtung zum Regenerieren, Heizen und Entschwefeln des NOx-Speicherkatalysators einer Brennkraftmaschine

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8464519B2 (en) 2009-01-28 2013-06-18 Friedrich Boysen Gmbh & Co. Kg Secondary air system
WO2016106994A1 (fr) * 2014-12-31 2016-07-07 安徽江淮汽车股份有限公司 Tuyau d'injection d'air secondaire et système d'injection d'air secondaire

Also Published As

Publication number Publication date
DE10327305A1 (de) 2005-01-05

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