GB2184485A - Air cell structure of a diesel engine piston combustion chamber - Google Patents

Air cell structure of a diesel engine piston combustion chamber Download PDF

Info

Publication number
GB2184485A
GB2184485A GB08625172A GB8625172A GB2184485A GB 2184485 A GB2184485 A GB 2184485A GB 08625172 A GB08625172 A GB 08625172A GB 8625172 A GB8625172 A GB 8625172A GB 2184485 A GB2184485 A GB 2184485A
Authority
GB
United Kingdom
Prior art keywords
air
piston
combustion chamber
chamber
ofthe
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.)
Granted
Application number
GB08625172A
Other versions
GB8625172D0 (en
GB2184485B (en
Inventor
Wallace Robert Wade
Charles Howard Humber
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.)
Ford Motor Co
Original Assignee
Ford Motor Co
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 Ford Motor Co filed Critical Ford Motor Co
Publication of GB8625172D0 publication Critical patent/GB8625172D0/en
Publication of GB2184485A publication Critical patent/GB2184485A/en
Application granted granted Critical
Publication of GB2184485B publication Critical patent/GB2184485B/en
Expired 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
    • F02F3/00—Pistons 
    • F02F3/28—Other pistons with specially-shaped head
    • F02F3/285—Other pistons with specially-shaped head the head being provided with an insert located in or on the combustion-gas-swept surface
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B21/00—Engines characterised by air-storage chambers
    • F02B21/02—Chamber shapes or constructions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B23/00—Other engines characterised by special shape or construction of combustion chambers to improve operation
    • F02B23/02—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition
    • F02B23/06—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston
    • F02B23/0603—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston at least part of the interior volume or the wall of the combustion space being made of material different from the surrounding piston part, e.g. combustion space formed within a ceramic part fixed to a metal piston head
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B23/00—Other engines characterised by special shape or construction of combustion chambers to improve operation
    • F02B23/02—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition
    • F02B23/06—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston
    • F02B23/0618—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston having in-cylinder means to influence the charge motion
    • F02B23/0627—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston having in-cylinder means to influence the charge motion having additional bores or grooves machined into the piston for guiding air or charge flow to the piston bowl
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B23/00—Other engines characterised by special shape or construction of combustion chambers to improve operation
    • F02B23/02—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition
    • F02B23/06—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston
    • F02B23/0636—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston the combustion space having a substantially flat and horizontal bottom
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B2275/00—Other engines, components or details, not provided for in other groups of this subclass
    • F02B2275/14—Direct injection into combustion chamber
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B23/00—Other engines characterised by special shape or construction of combustion chambers to improve operation
    • F02B23/02—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition
    • F02B23/06—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston
    • F02B23/0618—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston having in-cylinder means to influence the charge motion
    • F02B23/0624—Swirl flow
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B23/00—Other engines characterised by special shape or construction of combustion chambers to improve operation
    • F02B23/02—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition
    • F02B23/06—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston
    • F02B23/0645—Details related to the fuel injector or the fuel spray
    • F02B23/0669—Details related to the fuel injector or the fuel spray having multiple fuel spray jets per injector nozzle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B3/00—Engines characterised by air compression and subsequent fuel addition
    • F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
    • 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

Abstract

An air cell 26 in the piston stores air during the compression stroke of the piston and discharges the stored air into the combustion products during the expansion stroke of the piston. In one embodiment, the air chamber is an annular plenum in the piston 10 having a number of equally circumferentially spaced orifices 28 communicating with the combustion chamber 14 and directing jets of air into the combustion products in a direction opposite to the swirl motion of the combustion products in the chamber. A second embodiment provides a plurality of separate air cells (30, Figures 3 and 4) in the piston spaced around the circumference of the combustion chamber and each provided with a nozzle insert (36) defining an air jet during the expansion stroke of the piston to oxidize the particulates. <IMAGE>

Description

SPECIFICATION Air cell for diesel engine combustion chamber This invention relates in general to the combustion chamberof an automotivetype diesel engine, and more particularlyto onethat has an aircelifor oxidizing particulates and reducing emissions.
The use of air cells in indirect and direct injection diesel engines is known. SAE Paper 840515, Wade et al, dated February 27- March 2,1984, on page 18 refers to the use of an air cell in an indirect injection diesel engine to store high pressure air during the compression stroke and initial combustion phase and to subsequently inject the stored air into the perchamberthroat during the later stages of combustion to promote the continuation of particulate oxidation. No details of construction are shown. However, SAE Paper 831297.Kamimoto petal, dated September 12-15, 1983, page 107, shows in Figure 9 a test engine configuration with a combustion chamber having an air cell mounted over it. n this case, the cell has a single diagonally positioned orifice for directing the air into the bowl of the piston during the expansion stroke. Figure 16 on page 111 shows a further embodiment of the air cell for use eitherwith air or oil. In both ofthese cases, the air cell is mounted above the piston and the airjet intersects the fuel jet essentiallytangentially or at a slight angle, rather than in a directly opposite direction.
Other prior art relating in general to this invention is that to Goto et al, U.S. 4,175,533, Tanahashi, U.S.
4,175,535 okota et al, U.S. 4,128,092, Kovacs et al, U.S. 4,444,166, all showing auxiliary chambers communicating with the main combustion chamber; however, in each case, the auxiliary chamber is for combustion and not an airchamberforthepurpose of oxidizing particulates.
U.S. 3,919,982, Goto et al, does show a spark ignition engine with holes 3 in the top of the piston that are filled with airduring the intake stroke ofthe engine and expelled into the combustion chamber for oxidizing unburned hydrocarbons and carbon monooxide during the operation of the engine.
None of the cases above in the prior art, however, show a diesel engine type combustion chamber with a piston having integml therewith a pluralityofair nozzles communicating airstored in chambers to the combustion chamber during the expansion stroke of the piston to oxidize particulates.
It is, therefore, a primary object of the invention to provide a diesel engine combustion chamber construction in which an air cell with a nozzle orifice.
is provided integral with the piston for movement therewith to oxidize particulates commonly formed in diesel type engines.
According to the invention there is provided an air cell construction for a diesel engine having a swirl air motion, bowl-in-piston reentra nt combustion chamber (14), the piston (10) having at leastoneair chamber (26) formed therein opening into the combustion chamber (14), and a plurality of nozzle forming orifices (28) in the opening, the longitudinal axis of each nozzle (28) directing air from the nozzle in a direction into the airswirl in the chamber (14)to mix with and oxidize local particulate emissions therein.
A preferred construction embodying the invention provides an annular plenum formed in the outer peripheryofthe piston and having a number of equally circumferentially spaced orifices communicating with the swirl gas/ai r in the combustion chamber of the piston for mixing with the particulates therein to oxidize the same. An alternative construction provides a plurality of equally circumferentially spaced air chambers formed in the piston and provided with orificed cylindersattheopeningsoftheairchamberstothe piston bowl type combustion chamber constituting nozzles providing jet streams in this case directing air directly into the oncoming particulates to oxidize the same.
The invention will now be described further by way of example with reference to the accompanying drawings, in which: Figure lisa top plan view of a diesel enginetype piston embodying the invention; Figure2 is a cross-sectional view taken on a plane indicated by and viewed in the direction ofthe arrows ll-ll of Figure 1,and Figure 3 a nd 4 are views corresponding to those of Figures 1 and 2, respectively, showing an alternate construction.
Figures 1 and 2 show a piston 10 of the type commonly used in a direct injection diesel type engine utilizing compression ignition. The piston hasthe usual annular ring grooves 12, and in this case has a reentrant bowl-in-piston type combustion chamber 14formed in an insert 16 secured within a recess 18 inthe upperface 20 ofthe piston 10. The outer peripheral portion 24 of the insert 16 is shown formed with an annular plenum 26 that constitutes in this case an air cell or air chamber. The air cell/chamber is connected to the bowl type combustionchamberl4bya pluralityofequally circumferentially spaced orifices 28 that are spaced equally circumferentially around the bowl of the piston.The orifices are sized so as to constitute jet nozzles for injecting air into the swirl airfuel stream ofthe bowl 14 in a manner to be described.
Particulate emissions in a direct injection diesel engine originate from the local fuel-rich regions in the diffusion combustion process. Injection of air into the combustion chamber after the start of combustion is a technique with the potential for reducing particulate emissions. The air cell plenum 26 in this case is adapted to store high pressure air during the compression stroke ofthe piston and initial combustion phase for reinjection into the combustion products during the later stages ofthe expansion stroke of the piston. The injected air promotes the continuation of the particulate oxidation process at a time when the temperature in the combustion chamber is above 1600"k.
The plenum 26 in this case is sized to provide an air storage volume equal to a small percentage, in this case, from 1%to 10%, of the ciearance volume ofthe combustion chamber at top dead center position of the piston. It will be clear, however, that othersmall percentage volumes can be used within the scope of the invention. As stated previously, the airwould enter the chamber through the orifices 28 during the compression stroke, when the pressure differential causesaretofiowisfrom the bowl 14to the plenum 26. When the pressure differential reverses, when the piston is moving through its expansion downward stroke, the higher air pressure in the chamber 26 now forces the airthrough the orifice 28 to mix with the combustion products in the bowl 14.
Although notshown,the combustion products in the bowl 14 attain a swirl gas type motion during the compression stroke and initial combustion, the air from the plenum 26 injected through the orifices 28 therefore being directed, as clearly shown in Figure 1, directly into this swirl gas motion in a direction directly opposite to the direction of swirl gas motion to thoroughly mixwith and oxidize particulates.
The arifices 28 would be sized to provide an adequate penetration lane for the airjet, the direction ofthe orifice being selected to providetheairjetto the high temperature, fuel-rich region in the combustion chamber. In this case, the air nozzles are distributed in the combustion bowl equally circumferentiallywith respect to the plenum and bowl to improve the mixing of air and fuel-rich combustion products to enhance oxidation of the particulates.
Figure 1 and 2 show an annular plenum with four equally spaced orificed jets or nozzles 28 directing the air into the combustion chamber. Figures 3 and 4 show another embodiment in which four air cells 30 are provided distributed around the periphery ofthe combustion bowl. In this case, the conventional reentrant combustion bowl 14typically used in a high speed direct injection diesel engine again is shown. The four air cells 30 are arranged around the base of the combustion bowl with each air cell including an air storage volume 32 formed by drilling into the piston material to provide a volume equal again to a small percentage ofthe clearance volume attop dead center position ofthe piston.An aircell orifice 34 is formed by pressing or screwing a solid cylinder 36 containing the orifice into the portion of the air storage volume nearestthe combustion bowl.
Again, during the expansion stroke, the pressure in the combustion chamber decreases, causing the higher pressure air stored in the air cell to exit through the orifice. As stated previously, the orifice would be sized to provide an adequate penetration length forthe air jet. The air jet subsequently provides additional oxygen to the high temperature particulatesto enhance their oxidation. As in the case of the Figures 1 and 2 embodiment, the direction of the orifices, as shown in Figures 3 and 4, are selected to provide the airjetto a high temperature, fuel-rich region in the combustion chamber.
By locating the air cells in the piston, the air cells are always in close proximity with the rich combustion products located in the combustion bowl. As a result, the injected air is always provided atthe location where it can be most effective in oxidizing the particulates. Since the air cell orifices are directed againstthe direction of the air gas swirl in the combustion bowl, combustion chamber turbulence is increased to provide increased mixing ofthe particulates with the air for an increased oxidation rate of the particulates.
From theforegoing,therefore, it will be seen that the invention provides a diesel engine combustion chamber construction that enhances the oxidation of particulates and therefore reduces particulate emissions bythe use of simple air cells and orifices located in the piston for directing airintothe combustion products and particulates during the expansion stroke ofthe piston.

Claims (7)

1. An air cell construction for a diesel engine having a swirl air motion. bowl-in-piston reetrant type combustion chamber (14), the piston (10) having at least one air chamber (26) formed therein opening into the combustion chamber (14), and a plurality of nozzle forming orifices (28) in the opening, the longitudinal axis of each nozzle (28) directing airfrom the nozzle in a direction into the air swirl in the chamber (14) to mix with and oxidize local particulate emmisions therein.
2. A construction as in Claim 1, wherein the air chamber includes a plurality of aircells equally spaced circumferentially around the body of the piston and each having an air directing nozzle directing air in the cell directly into the oncoming swirl air stream.
3. A construction as in Claim 1, wherein the air chamber is an annular plenum in the body ofthe piston having a plurality of equally circumferentially spaced air nozzles connecting the plenum to the combustion chamber, the nozzles directing airfrom the plenum directly into theswirl airstream ina direction opposite to that of the swirl airstream.
4. A construction as in Claim 1, wherein the nozzles each consistof a solid cylinder containing an orifice, the cylinder being secured into each opening into the combustion chamber.
5. A construction as in Claim 2, wherein the volume ofthe air cells is a small percentage ofthe clearance volume of the combustion chamber at top dead center position of the piston.
6. Aconstruction as in Claim 3, wherein the volume ofthe plenum is a small percentage one percent ofthe clearance volume of the combustion chamber at top dead center position of the piston.
7. A construction as in Claim 1, wherein the air is forced intothechamberduringthecompression stroke ofthe piston and is expelled from the chamber during the expansion stroke of the piston.
GB8625172A 1985-12-23 1986-10-21 Air cell for diesel engine combustion chamber Expired GB2184485B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US81270285A 1985-12-23 1985-12-23

Publications (3)

Publication Number Publication Date
GB8625172D0 GB8625172D0 (en) 1986-11-26
GB2184485A true GB2184485A (en) 1987-06-24
GB2184485B GB2184485B (en) 1989-10-11

Family

ID=25210380

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8625172A Expired GB2184485B (en) 1985-12-23 1986-10-21 Air cell for diesel engine combustion chamber

Country Status (3)

Country Link
JP (1) JPS62157227A (en)
DE (1) DE3642376A1 (en)
GB (1) GB2184485B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998017900A1 (en) * 1996-10-17 1998-04-30 T & N Technology Limited Piston with cavity
US5809962A (en) * 1996-03-20 1998-09-22 Perkins Limited Method for producing a piston for an internal combustion engine and a piston produced by the method

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB311834A (en) * 1927-12-23 1929-05-23 Oil Engine Dev Company Improvements relating to liquid-fuel injection apparatus for oil-engines
GB355459A (en) * 1929-08-05 1931-08-27 Maschinenfabrik Augsburg-Nuernberg A.G.
GB380692A (en) * 1931-02-14 1932-09-22 Lang Franz Improvements in internal combustion oil engines

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE676997C (en) * 1931-11-20 1939-06-16 Fahrzeug Und Motorenwerke G M Self-igniting, air-compressing internal combustion engine
DE669224C (en) * 1935-05-04 1938-12-20 Else Gockerell Air-compressing injection internal combustion engine with self-ignition
FR1457214A (en) * 1965-12-06 1966-10-28 Transports Automobiles Des Hau Thermal engine with air reserve chambers in the pistons and causing, because of their arrangement, a very strong turbulence of the gases during combustion
DE2823483A1 (en) * 1978-05-30 1979-12-06 Kloeckner Humboldt Deutz Ag Diesel engine combustion chamber system - has fuel jet striking throttle opening of auxiliary combustion chamber under weak air movement
DE3405715A1 (en) * 1983-02-17 1984-09-06 Hans 4600 Dortmund Dressendörfer Internal combustion engine for low-volatility fuels

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB311834A (en) * 1927-12-23 1929-05-23 Oil Engine Dev Company Improvements relating to liquid-fuel injection apparatus for oil-engines
GB355459A (en) * 1929-08-05 1931-08-27 Maschinenfabrik Augsburg-Nuernberg A.G.
GB380692A (en) * 1931-02-14 1932-09-22 Lang Franz Improvements in internal combustion oil engines

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5809962A (en) * 1996-03-20 1998-09-22 Perkins Limited Method for producing a piston for an internal combustion engine and a piston produced by the method
WO1998017900A1 (en) * 1996-10-17 1998-04-30 T & N Technology Limited Piston with cavity

Also Published As

Publication number Publication date
GB8625172D0 (en) 1986-11-26
DE3642376A1 (en) 1987-07-02
GB2184485B (en) 1989-10-11
JPS62157227A (en) 1987-07-13

Similar Documents

Publication Publication Date Title
US5605125A (en) Direct fuel injection stratified charge engine
US4612898A (en) Cylinder head for a piston internal combustion engine
US4852525A (en) Combustion chamber in internal combustion engine
US4538566A (en) Combustion chamber in a diesel engine
EP0544920A1 (en) Direct injection type compression ignition internal combustion engine
EP0205000B1 (en) Combustion chamber for an internal-combustion engine
JP2574239B2 (en) Apparatus and method for generating agitated flow in an internal combustion engine
US4733643A (en) Combustion chamber arrangement for an internal combustion engine
JPS61218772A (en) Fuel injection device for diesel engine
US4913111A (en) Turbulence generator for two-stroker spark-assisted diesel engines
GB2184485A (en) Air cell structure of a diesel engine piston combustion chamber
JPS5851215A (en) Combustion chamber for vortex chamber type diesel engine
US5613471A (en) Diesel engine using fuel jet impingement and diffusion
JPH0623540B2 (en) Pentorf type direct injection internal combustion engine
EP0828066B1 (en) Combustion chamber of diesel engine
JPH0147606B2 (en)
JP3039155B2 (en) Fuel combustion promotion method for diesel engine
EP0909893A2 (en) Direct injection diesel engine
JP2582364B2 (en) Combustion chamber of internal combustion engine
JP3341606B2 (en) Fuel injection nozzle for internal combustion engine
JPS6329016A (en) Subchamber type diesel combustion chamber
JPS6145294Y2 (en)
JP2934784B2 (en) Fuel injection two-stroke engine
JPS5968518A (en) Combustion chamber for engine with pre-chamber
JP2927521B2 (en) Fuel injection two-stroke engine

Legal Events

Date Code Title Description
746 Register noted 'licences of right' (sect. 46/1977)
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19921021