`IN THE UNITED STATES PATENT AND TRADEMARK OFFICE
`
`Applicant: Daniel R. Cohn et a1.
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`Examiner:
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`Not Yet Assigned
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`Serial No.: Not Yet Assigned
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`Filing Date: Filed Herewith
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`Art Unit:
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`Not Yet Assigned
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`Confirmation No.1 Not Yet Assigned
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`Title: FUEL MANAGEMENT SYSTEM FOR VARIABLE ETHANOL OCTANE
`ENHANCEMENT OF GASOLINE ENGINES
`
`PRELIMINARY AMENDMENT
`
`Via EFS— Web
`Commissioner for Patents
`PO. Box 1450
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`Alexandria, VA 22313-1450
`
`Dear Sir:
`
`Please preliminarily amend the application as follows.
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`FORD Ex. 1118, page 1
`IPR2020-00013
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`FORD Ex. 1118, page 1
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`Application No. Filed Hercwith
`Date: June 15, 2010
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`Docket No.: 11381.109439
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`In The Specification
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`Please amcnd paragraph [0001] on page 1 as follows:
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`This application is a continuation of United States PatentflApplication No. 12/329‘729
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`filed onfDecember 8; 2008 which is a continuation of United States Patent Application No.
`
`ll/840,719 filed on August 17, 2007, which is a continuation of United States Patent Application
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`No. 10/991,774, which is now issued as United States Patent No. 7,314,033.
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`FORD Ex. 1118, page 2
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`Application No. Filed Herewith
`Date: June 15. 2010
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`Docket No: 11381.109439
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`Listing of Claims
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`Claims 1 — 32 (cancelled)
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`33.
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`(new) A spark ignition engine system for which the] is introduced into the engine from a
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`first source and a fiiel is separately introduced into the engine fiom a second source by direct
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`injection comprising:
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`a spark ignition engine;
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`a first means for introducing the fuel from the first source into the engine;
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`a second means for direct injection of the fuel fiom the second source into the engine,
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`wherein during part ot‘the engine operating time, the engine receives both the fuel from the first
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`source and the fuel that is directly injected from the second source; and
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`a fuel management system which varies the relative amount of the fuel from the second
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`source that is introduced into the engine so as to prevent knock, wherein the fuel management
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`system employs information from a knock detector and uses closed loop control to control the
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`amount of directly injected fuel from the second source; and
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`wherein the engine is operated with a substantially stoiehiometric fuel/air ratio.
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`34. (new) The engine system of claim 33, wherein the second source contains a liquid that
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`could be employed to operate the engine without the addition of fuel from the first source.
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`35. (new) The engine system ofclaim 33 or 34 , wherein the fuel from the second source is
`alcohol.
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`36.
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`(new) The engine system of claim 35, wherein the alcohol is methanol.
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`37.
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`(new) The engine system of claim 35, wherein the alcohol is ethanol.
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`38.
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`(new) The engine system of claim 33 where an alcohol—water mixture is directly injected
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`into the engine from the second source
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`(new) The engine system of claim 33 or 34, wherein the engine is turbocharged or
`39.
`supercharged
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`FORD Ex. 1118, page 3
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`Application No. Filed Herewith
`Date: June 15, 2010
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`Docket No.: 11381.109439
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`40. (new) The engine system of claim 33 or 34, wherein the fuel from the first source is
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`gasoline.
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`41. (new) The engine system of claim 33 or 34, wherein the fuel from the second source is
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`injected so as to result in a non-uniform distribution in the engine cylinder.
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`42.
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`(new) The engine system of claim 41, wherein the fuel from the second source is injected so
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`as to be more concentrated near the periphery of the engine cylinder, and
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`the ratio of the energy of the fuel from the second source to fuel from the first source
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`is sufficiently high to prevent knock but the alcohol energy fraction is reduced as
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`compared to the situation using a uniform distribution.
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`43. (new) The engine system of claim 33 or 34, wherein the fuel management system employs a
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`microprocessor for control of the relative amount of fuel from the second source that is directly
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`injected into the engine using information from a knock sensor, and
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`wherein the relative amount of the fuel from the second source increases with increasing
`torque, and
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`wherein the fuel management system minimizes the amount of directly injected fuel from
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`the second source that is used over a drive cycle.
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`44. (new) The engine system ofclaim 43 fiirther including open loop control with a look up
`table.
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`45. (new) The engine system of claim 33, wherein spark retard is used and is varied according
`
`to the consumption of the fuel from the second tank.
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`46.
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`(new) A spark ignition engine system into which fiiel is introduced into the engine from a
`
`first source and a fuel from a second source is introduced into the engine comprising:
`
`a spark ignition engine;
`
`a means for introducing fuel into the engine from the first source; ,
`
`a second means for introducing the fuel from the second source into the engine wherein
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`during part of the engine operating time, the engine receives both the fuel from the first source
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`and the fuel from the second source; and
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`FORD Ex. 1118, page 4
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`Application No. Filed Herewith
`Date: June 15, 2010
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`Docket No.: 1138 1.109439
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`a fuel management system which varies the relative amount of the fuel from the second
`
`source that is introduced into the engine so as to prevent knock, wherein the fuel management
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`system uses closed loop control to control the amount of fuel fiom the second source and
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`employs information fiom a knock detector, and
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`wherein the engine is operated with a substantially stoiehiometric fuel/air ratio.
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`47.
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`(new) The engine system of claim 46, wherein the second source contains a liquid which
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`could be used to operate the engine without fuel from the first source
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`48.
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`(new) The engine system of claim 46 or 47, wherein the fuel from the second source is
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`alcohol.
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`49. (new) The engine system of claim 48, wherein the alcohol is methanol.
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`50. (new) The engine system of claim 48, wherein the alcohol is ethanol.
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`51. (new) The engine system of claims 46 or 47, wherein the second source contains a fuel
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`which is an alcohol-water mixture.
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`52.
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`(new) The engine system of claims 46 or 47, wherein the engine is turbo charged to
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`supercharged.
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`53.
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`(new) The engine system of claims 46 or 47 , wherein the fuel from the first source is
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`gasoline.
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`54. (new) The engine system of claims 46 or 47, wherein the fuel management system employs
`
`a microprocessor for control of the relative amount of fuel from the second source that is
`
`introduced into the engine using information from a knock sensor, and wherein
`
`the relative amount of fuel from the second source increases with increasing torque, and
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`wherein the fuel management system minimizes the amount of directly injected fuel from
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`the second source that is used over a drive cycle.
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`(new) The engine system of claim 54 further including open loop control with a look up
`55.
`table.
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`FORD Ex. 1118, page 5
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`Application No. Filed Herewith
`Date: June 15,2010
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`Docket No: 11381.109439
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`56. (new) The engine system of claims 46 or 47, wherein spark retard is used and is varied
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`according to the consumption of the fuel from the second tank.
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`FORD Ex. 1118, page 6
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`Application No. Filed Herewith
`Date: June 15, 2010
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`Docket Nu: 11381109439
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`Remarks
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`New claims 33 ,1 56 more particularly point out and distinctly claim the invention. No
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`new matter is being introduced.
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`Regpectfill/yifubmitted,
`i
`g
`« ~,. fl
`w
`j
`
`
`y W Jv»»ff(»’
`Sam Pasternack
`
`Registration N0.: 29576
`Massachusetts Institute of Technology
`Five Cambridge Center
`Room NE25-230
`
`Cambridge, MA 02412—1493
`617.258.7171
`
`FORD Ex. 1118, page 7
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`FORD Ex. 1118, page 7
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`Fuel Management System for Variable Ethanol Octane Enhancement
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`of Gasoline Engines
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`[0001]
`
`This application is a continuation of United States Patent Application No. l l/840,7l9
`
`filed on August 17, 2007, which is a continuation of United States Patent Application No.
`
`10/991,774, which is now issued as United States Patent No. 7,314,033.
`
`BACKGROUND
`
`[0002]
`
`This invention relates to spark ignition gasoline engines utilizing an antiknock agent
`
`which is a liquid fuel with a higher octane number than gasoline such as ethanol to improve
`
`engine efficiency.
`
`[0003]
`
`It is known that the efficiency of spark ignition (SI) gasoline engines can be increased
`
`by high compression ratio operation and particularly by engine downsizing. The engine
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`downsizing is made possible by the use of substantial pressure boosting From either
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`turbocharging or supercharging. Such pressure boosting makes it possible to obtain the same
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`performance in a significantly smaller engine.
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`_S__e_e, J. Stokes, et al., “A Gasoline Engine
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`Concept For Improved Fuel Economy The Lean—Boost System,” SAE Paper 2001-01—2902.
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`The use of these techniques to increase engine efficiency, however. is limited by the onset of
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`engine knock. Knock is the undesired detonation of fuel and can severely damage an engine. if
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`knock can be prevented, then high compression ratio operation and high pressure boosting can be
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`used to increase engine efficiency by up to twenty—five percent
`
`[0004] Octane number represents the resistance of a fuel to knocking but the use of higher
`
`octane gasoline only modestly alleviates the tendency to knock. For example, the difference
`
`between regular and premium gasoline is typically six octane numbers. That is significantly less
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`than is needed to realize fully the efficiency benefits of high compression ratio or turbocharged,
`
`operation. There is thus a need for a practical means for achieving a much higher level of octane
`
`enhancement so that engines can be operated much more efficiently.
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`loflS
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`[0005]
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`It is known to replace a portion of gasoline with small amounts of ethanol added at the
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`refinery. Ethanol has a blending octane number (ON) of 110 (versus 95 for premium gasoline)
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`(see J.B. Heywood, “Internal Combustion Engine Fundamentals,” McGraw Hill, 1988, p. 477)
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`and is also attractive because it is a renewable energy, biomass-derived fiiel, but the small
`
`amounts of ethanol that have heretofore been added to gasoline have had a relatively small
`
`impact on engine performance. Ethanol is much more expensive than gasoline and the amount
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`of ethanol that is readily available is much smaller than that of gasoline because of the relatively
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`limited amount of biomass that is available for its production An object of the present invention
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`is to minimize the amount of ethanol or other antiknock agent that is used to achieve a given
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`level of engine efficiency increase. By restricting the use of ethanol to the relatively small
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`fraction of time in an operating cycle when it is needed to prevent knock in a higher load regime
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`and by minimizing its use at these times, the amount of ethanol that is required can be limited to
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`a. relatively small fraction of the fuel used by the spark ignition gasoline engine.
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`SUMMARY
`
`[0006]
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`In one aspect, the invention is a fuel management system for efficient operation of a
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`spark ignition gasoline engine including a source of an antiknock agent such as ethanol. An
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`injector directly injects the ethanol into a cylinder of the engine and a fuel management system
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`controls injection of the antiknock agent into the cylinder to control knock with minimum use of
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`the antiknock agent. A preferred antiknock agent is ethanol. Ethanol has a high heat of
`
`vaporization so that there is substantial cooling of the air-fuel charge to the cylinder when it is
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`injected directly into the engine. This cooling effect reduces the octane requirement of the
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`engine by a considerable amount in addition to the improvement in knock resistance from the
`
`relatively high octane number of ethanol. Methanol, tertiary butyl alcohol. MTBE. ETBE, and
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`TAME may also be used. Wherever ethanol is used herein it is to be understood that other
`
`antiknoek agents are contemplated.
`
`[0007]
`
`The fuel management system uses a fuel management control system that may use a
`
`microprocessor that operates in an open loop fashion on a predetermined correlation between
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`octane number enhancement and fraction of fuel provided by the antiknoek agent. To conserve
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`the ethanol, it is preferred that it be added only during portions of a drive cycle requiring knock
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`resistance and that its use be minimized during these times. Alternatively, the gasoline engine
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`20:"15
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`may include a knock sensor that provides a feedback signal to a fuel management
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`microprocessor system to minimize the amount of the ethanol added to prevent knock in a closed
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`loop fashion.
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`[0008]
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`In one embodiment the injectors stratify the ethanol to provide non—uniform deposition
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`within a cylinder. For example, the ethanol may be injected proximate to the cylinder walls and
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`swirl can create a ring of ethanol near the walls,
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`[0009]
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`In another embodiment of this aspect of the invention, the system includes a measure
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`of the amount of the antiknock agent such as ethanol in the source containing the antiknock agent
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`to control turbocharging, supercharging or spark retard when the amount of ethanol is low.
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`[0010]
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`The direct injection of ethanol provides substantially a 13”C drop in temperature for
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`every ten percent of fuel energy provided by ethanol. An instantaneous octane enhancement of
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`at least 4 octane numbers may be obtained for every 20 percent of the engine’s energy coming
`from the ethanol.
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`BRIEF DESCRIPTION OF THE DRAWINGS
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`[0011]
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`FIG. 1 is a block diagram of one embodiment of the invention disclosed herein.
`
`[0012]
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`FIG. 2 is a graph of the drop in temperature within a cylinder as a function of the
`
`fraction of energy provided by ethanol.
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`[0013]
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`FIG. 3 is a schematic illustration of the stratification of cooler ethanol charge using
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`direct injection and swirl motion for achieving thermal stratification.
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`[0014]
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`FIG. 4 is a schematic illustration showing ethanol stratified in an inlet manifold.
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`[0015]
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`FIG. 5 is a block diagram of an embodiment of the invention in which the fuel
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`management microprocessor is used to control a turbocharger and spark retard based upon the
`amount of ethanol in a fuel tank.
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`DETAILED DESCRIPTION
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`[0016] With reference first to FIG. 1, a spark ignition gasoline engine 10 includes a knock
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`sensor 12 and a fuel management microprocessor system 14. The fuel management
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`microprocessor system 14 controls the direct injection of an antiknock agent such as ethanol
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`from an ethanol tank 16. The fuel management microprocessor system 14 also controls the
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`delivery of gasoline from a gasoline tank 18 into engine manifold 20. A turbocharger 22 is
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`30f15
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`provided to improve the torque and power density of the engine 10. The amount of ethanol
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`injection is dictated either by a predetermined correlation between octane number enhancement
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`and fraction of fuel that is provided by ethanol in an open loop system or by a closed loop
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`control system that uses a signal from the knock sensor 12 as an input to the fuel management
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`microprocessor 14. In both situations. the fuel management processor 14 will minimize the
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`amount of ethanol added to a. cylinder while still preventing knock.
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`It is also contemplated that
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`the fuel management microprocessor system 14 could provide a combination of open and closed
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`loop control.
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`[0017] As show in FIG. 1 it is preferred that ethanol be directly injected into the engine 10.
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`Direct injection substantially increases the benefits of ethanol addition and decreases the required
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`amount of ethanol. Recent advances in fuel injector and electronic control technology allows
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`fuel injection directly into a spark ignition engine rather than into the manifold 20. Because
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`ethanol has a high heat of vaporization there will be substantial cooling when it is directly
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`injected into the engine 10. This cooling effect further increases knock resistance by a
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`considerable amount.
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`in the embodiment of FIG. 1 port fuel injection of the gasoline in which
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`the gasoline is injected into the manifold rather than directly injected into the cylinder is
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`preferred because it is advantageous in obtaining good air/fuel mixing and combustion stability
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`that are difficult to obtain with direct injection.
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`[0018]
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`Ethanol has a heat of vaporization of 840klx’kg, while the heat of vaporization of
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`gasoline is about 350kJ/k g. The attractiveness of ethanol increases when compared with
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`gasoline on an energy basis, since the lower heating value of ethanol is 26.9MJ/kg while for
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`gasoline it is about 44MJ/kg. Thus, the heat of vaporization per Joule of combustion energy is
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`0.031 for ethanol and 0.008 for gasoline. That is, for equal amounts of energy the required heat
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`of vaporization of ethanol is about four times higher than that ofgasoline. The ratio of the heat
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`of vaporization per unit air required for stoiehiometric combustion is about 94 kJ/kg of air for
`
`ethanol and 24 kJ/kg of air for gasoline, or a factor of four smaller. Thus, the net effect of
`
`cooling the air charge is about four times lower for gasoline than for ethanol (for stoiehiometric
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`mixtures wherein the amount of air contains oxygen that is just sufficient to combust all of the
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`fuel).
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`4oflS
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`[0019]
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`In the case of ethanol direct injection according to one aspect of the invention, the
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`charge is directly cooled. The amount of cooling due to direct injection of ethanol is shown in
`
`FIG. 2.
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`lt is assumed that the air/fuel mixture is stoiehiornetric without exhaust gas recirculation
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`(EGR), and that gasoline makes up the rest of the fuel.
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`It is further assumed that only the ethanol
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`contributes to charge cooling. Gasoline is vaporized in the inlet manifold and does not
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`contribute to cylinder charge cooling. The direct ethanol injection provides about 13°C of
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`cooling for each l0% of the fuel energy provided by ethanol.
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`It is also possible to use direct
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`injection of gasoline as well as direct injection of ethanol. However, under certain conditions
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`there can be combustion stability issues.
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`[0020}
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`The temperature decrement because of the vaporization energy of the ethanol decreases
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`with lean operation and with EGR, as the thermal capacity of the cylinder charge increases. If
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`the engine operates at twice the stoichiometric air/fuel ratio, the numbers indicated in FIG. 2
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`decrease by about a factor of 2 (the contribution of the ethanol itself and the gasoline is relatively
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`modest). Similarly, for a 20% EGR rate, the cooling effect of the ethanol decreases by about
`25%.
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`[0021]
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`The octane enhancement effect can be estimated from the data in FIG. 2. Direct
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`injection of gasoline results in approximately a five octane number decrease in the octane
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`number required by the engine, as discussed by Stokes, er al. Thus the contribution is about five
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`octane numbers per 30K drop in charge temperature. As ethanol can decrease the charge
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`temperature by about 120K, then the decrease in octane number required by the engine due to the
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`drop in temperature, for 100% ethanol, is twenty octane numbers. Thus, when 100% of the fuel
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`is provided by ethanol, the octane number enhancement is approximately thirty—five octane
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`numbers with a twenty octane number enhancement coming from direct injection cooling and a
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`fifteen octane number enhancement coming from the octane number of ethanol. From the above
`
`considerations, it can be projected that even if the octane enhancement from direct cooling is
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`significantly lower, a total octane number enhancement of at least 4 octane numbers should be
`
`achievable for every 20% of the total fuel energy that is provided by ethanol.
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`[0022] Alternatively the ethanol and gasoline can be mixed together and then port injected
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`through a single injector per cylinder, thereby decreasing the number of injectors that would be
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`used. However, the air charge cooling benefit from ethanol would be lost.
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`SONS
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`[0023] Alternatively the ethanol and gasoline can be mixed together and then port fuel injected
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`using a single injector per cylinder, thereby decreasing the number of injectors that would be
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`used. However, the substantial air charge cooling benefit from ethanol would be lost. The
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`volume of fuel between the mixing point and the port fuel injector should be minimized in order
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`to meet the demanding dynamic oclane—enhancement requirements of the engine.
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`[0024]
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`Relatively precise determinations of the actual amount of octane enhancement from
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`given amounts of direct ethanol injection can be obtained from laboratory and vehicle tests in
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`addition to detailed calculations. These correlations can be used by the fuel management
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`microprocessor system 14.
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`[0025] An additional benefit ot‘using ethanol for octane enhancement is the ability to use it in
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`a mixture with water. Such a mixture can eliminate the need for the costly and energy
`
`consuming water removal step in producing pure ethanol that must be employed when ethanol is
`
`added to gasoline at a refinery. Moreover, the water provides an additional cooling (due to
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`vaporization) that further increases engine knock resistance. In contrast the present use of
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`ethanol as an additive to gasoline at the refinery requires that the water be removed from the
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`ethanol.
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`[0026]
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`Since unlike gasoline, ethanol is not a good lubricant and the ethanol fuel injector can
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`stick and not open, it is desirable to add a lubricant to the ethanol. The lubricant will also
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`denature the ethanol and make it unattractive for human consumption.
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`[0027]
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`Further decreases in the required ethanol for a given amount of octane enhancement
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`can be achieved with stratification (non—uniform deposition) of the ethanol addition. Direct
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`injection can be used to place the ethanol near the walls of the cylinder where the need for knock
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`reduction is greatest. The direct injection may be used in combination with swirl. This
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`stratification of the ethanol in the engine further reduces the amount of ethanol needed to obtain
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`a given amount of octane enhancement. Because only the ethanol is directly injected and
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`because it is stratified both by the injection process and by thermal centrifugation, the ignition
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`stability issues associated with gasoline direct injection (GDI) can be avoided.
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`[0028]
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`it is preferred that ethanol be added to those regions that make up the end—gas and are
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`prone to auto-ignition. These regions are near the walls of the cylinder. Since the end-gas
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`6ot‘i5
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`contains on the order of 25% of the fuel, substantial decrements in the required amounts of
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`ethanol can be achieved by stratifying the ethanol.
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`[0029]
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`In the case of the engine 10 having substantial organized motion (such as swirl), the
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`cooling will result in forces that thermally stratify the discharge (centrifugal separation of the
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`regions at different density due to different temperatures). The effect of ethanol addition is to
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`increase gas density since the temperature is decreased. With swirl the ethanol mixture will
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`automatically move to the zone where the end~gas is, and thus increase the anti~knock
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`effectiveness of the injected ethanol. The swirl motion is not affected much by the compression
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`stroke and thus survives better than tumble—like motion that drives turbulence towards top-dead-
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`center (TDC) and then dissipates.
`
`It should be pointed out that relatively modest swirls result in
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`large separating (centrifugal) forces. A 3m/s swirl motion in a 5cm radius cylinder generates
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`accelerations of about 200m/s2, or about 20g’s.
`
`[0030]
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`FIG. 3 illustrates ethanol direct injection and swirl motion for achieving thermal
`
`stratification. Ethanol is predominantly on an outside region which is the end- gas region.
`
`FIG. 4 illustrates a possible stratification of the ethanol in an inlet manifold with swirl motion
`
`and thermal centrifugation maintaining stratification in the cylinder. In this case of port injection
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`of ethanol, however, the advantage of substantial charge cooling may be lost.
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`[0031] With reference again to FIG. 2, the effect of ethanol addition all the way up to 100%
`
`ethanol injection is shown. At the point that the engine is l00% direct ethanol injected, there
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`may be issues of engine stability when operating with only stratified ethanol injection that need
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`to be addressed. In the case of stratified operation it may also be advantageous to stratify the
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`injection of gasoline in order to provide a relatively uniform equivalence ratio across the cylinder
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`(and therefore lower concentrations of gasoline in the regions Where the ethanol is injected).
`
`This situation can be achieved, as indicated in FIG. 4, by placing fuel in the region of the inlet
`manifold that is void of ethanol,
`
`[0032]
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`The ethanol used in the invention can either be contained in a separate tank from the
`
`gasoline or may be separated from a gasoline/ethanol mixture stored in one tank.
`
`[0033]
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`The instantaneous ethanol injection requirement and total ethanol consumption over a
`
`drive cycle can be estimated from information about the drive cycle and the increase in torque
`
`(and thus increase in compression ratio, engine power density, and capability for downsizing)
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`70f15
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`that is desired. A plot of the amount of operating time spent at various values of torque and
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`engine speed in FTP and U806 drive cycles can be used.
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`It is necessary to enhance the octane
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`number at each point in the drive cycle where the torque is greater than permitted for knock free
`
`operation with gasoline alone. The amount of octane enhancement that is required is determined
`
`by the torque level.
`
`[0034] A rough illustrative calculation shows that only a small amount of ethanol might be
`
`needed over the drive cycle. Assume that it is desired to increase the maximum torque level by a
`
`factor of two relative to what is possible without direct injection ethanol octane enhancement.
`
`Information about the operating time for the combined FTP and U806 cycles shows that
`
`approximately only 10 percent of the time is spent at torque levels above 0.5 maximum torque
`
`and less than 1 percent of the time is spent above 0.9 maximum torque. Conservatively
`
`assuming that lot) 0/0 ethanol addition is needed at maximum torque and that the energy fraction
`
`of ethanol addition that is required to prevent knock decreases linearly to zero at 50 percent of
`
`maximum torque, the energy fraction provided by ethanol is about 30 percent. During a drive
`
`cycle about 20 percent of the total fuel energy is consumed at greater than 50 percent of
`
`maximum torque since during the 10 percent of the time that the engine is operated in this
`
`regime, the amount of fuel consumed is about twice that which is consumed below 50 percent of
`
`maximum torque. The amount of ethanol energy consumed during the drive cycle is thus roughly
`
`around 6 percent (30 percent x 0.2) of the total fuel energy.
`
`[0035]
`
`In this case then, although 100% ethanol addition was needed at the highest value of
`
`torque, only 6% addition was needed averaged over the drive cycle. The ethanol is much more
`
`effectively used by varying the level of addition according to the needs of the drive cycle.
`
`[0036]
`
`Because of the lower heat of combustion of ethanol, the required amount of ethanol
`
`would be about 9% of the weight of the gasoline fuel or about 9% of the volume (since the
`
`densities of ethanol and gasoline are comparable). A separate tank with a capacity of about 1.8
`
`gallons would then be required in automobiles with twenty gallon gasoline tanks. The stored
`
`ethanol content would be about 9% of that of gasoline by weight, a number not too different
`
`from present-day reformulated gasoline. Stratification of the ethanol addition could reduce this
`
`amount by more than a factor of two. An on-linc ethanol distillation system might alternatively
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`8 Qt 15
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`FORD Ex. 1118, page 15
`IPR2020-00013
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`FORD Ex. 1118, page 15
` IPR2020-00013
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`be employed but would entail elimination or reduction of the increase torque and power available
`
`from turbocharging.
`
`[0037]
`
`Because of the relatively small amount of ethanol and present lack of an ethanol
`
`fueling infrastructure. it is important that the ethanol vehicle be operable if there is no ethanol on
`
`the vehicle. The engine system can be designed such that although the torque and power benefits
`
`would be lower when ethanol is not available, the vehicle could still be operable by reducing or
`
`eliminating turbocharging capability and/or by increasing spark retard so as to avoid knock. As
`
`shown in FIG. 5, the fuel management microprocessor system 14 uses ethanol fuel level in the
`
`ethanol tank 16 as an input to control the turbocharger 22 (or supercharger or spark retard, not
`
`shown). As an example, with on-demand ethanol octane enhancement, a 4-cylinder engine can
`
`produce in the range of 280 horsepower with appropriate turbocharging or supercharging but
`
`could also be drivable with an engine power of 140 horsepower without the use of ethanol
`
`according to the invention.
`
`[0038]
`
`The impact of a small amount of ethanol upon fuel efficiency through use in a higher
`
`efficiency engine can greatly increase the energy value of the ethanol. For example, gasoline
`
`consumption could be reduced by 20% due to higher efficiency engine operation from use of a
`
`high compression ratio. strongly turbocharged operation and substantial engine downsizing. The
`
`energy value of the ethanol, including its value in direct replacement of gasoline (5% of the
`
`energy of the gasoline), is thus roughly equal to 25% of the gasoline that would have been used
`
`in a less efficient engine without any ethanol. The 5% gasoline equivalent energy value of
`
`ethanol has thus been leveraged up to a 25% gasoline equivalent value. Thus, ethanol can cost
`
`roughly up to five times that of gasoline on an cncrgy basis and still be economically attractive.
`
`The use of ethanol as disclosed herein can be a much greater value use than in other ethanol
`
`applications.
`
`[0039] Although the above discussion has Featured ethanol as an exemplary anti~knock agent,
`
`the same approach can be applied to other high octane fuel and fuel additives with high
`
`vaporization energies such as methanol (with higher vaporization energy per unit fuel), and other
`
`anti—knock agents such as tertiary butyl alcohol, or ethers such as methyl tertiary butyl ether
`
`(MTBE), ethyl tertiary butyl cthcr (ETBE), or tertiary amyl methyl ether (TAME).
`
`9oflS
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`FORD Ex. 1118, page 16
`IPR2020-00013
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`FORD Ex. 1118, page 16
` IPR2020-00013
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`
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`[0040]
`
`It is recognized that modifications and variations of the invention disclosed herein will
`
`be apparent to those of ordinary skill in the art and it is intended that all such modifications and
`
`variations be included within the scope of the appended claims.
`
`10 0115
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`FORD Ex. 1118, page 17
`IPR2020-00013
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`FORD Ex. 1118, page 17
` IPR2020-00013
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`What is claimed is:
`
`CLAIMS
`
`1.
`
`A spark ignition engine system for which fuel is introduced into the engine from a first
`
`source and a liquid is separately introduced into the engine from a second source by direct
`
`injection comprising:
`
`a spark ignition engine;
`
`a first means for introducing the fuel from the first source into the engine;
`
`a second means for direct injection of the liquid from the second source into the engine,
`
`wherein dining part of the engine operating time, the engine receives both the fuel from the first
`
`source and the liquid that is directly injected from the second source; and,
`
`a fuel management system which varies the relative amount of the liquid from the second
`
`source that is introduced into the engine so as to prevent knock, wherein the fuel management
`
`system e