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Stoichiometric Air-Fuel Ratios of Automotive Fuels
- Ground Vehicle Standard
Published March 17, 2015 by SAE International in United States
Downloadable datasets availableAnnotation ability available
The mass of air required to burn a unit mass of fuel with no excess of oxygen or fuel left over is known as the stoichiometric air-fuel ratio. This ratio varies appreciably over the wide range of fuels - gasolines, diesel fuels, and alternative fuels - that might be considered for use in automotive engines.
Although performance of engines operating on different fuels may be compared at the same air-fuel ratio or same fuel-air ratio, it is more appropriate to compare operation at the same equivalence ratio, for which a knowledge of stoichiometric air-fuel ratio is a prerequisite.
This SAE Recommended Practice summarizes the computation of stoichiometric air-fuel ratios from a knowledge of a composition of air and the elemental composition of the fuel without a need for any information on the molecular weight of the fuel.
A recent SAE paper has been added to the references and its use discussed. For clarity, the references have been numbered and footnotes modified. IUPAC atomic weights were updated and equations and tables were modified to reflect the latest atomic weights.
|Technical Paper||Exhaust Emission Based Air-Fuel Ratio Model (I): Literature Reviews and Modelling|
|Technical Paper||No Major Backsliding in Air Quality when Replacing MTBE with Isooctane in CARB Gasoline|
Data Sets - Support Documents
|TABLE 1||MOLECULAR WEIGHTS AND ASSUMED FRACTIONAL VOLUME - COMPOSITION OF SEA LEVEL DRY AIR|
|TABLE A1||WEIGHT OF ELEMENTS IN 96.0 G OF ETHANOL (C H OH)|
|TABLE A2||WEIGHT OF ELEMENTS IN 4.0 G OF WATER (H O)|
|TABLE A3||WEIGHT OF ELEMENTS IN 100 G OF AZEOTROPE|
Fuels and Lubricants TC 7 Fuels Committee
The Fuels Technical Committee 7 is responsible for the development of SAE Standards, Recommended Practices, Information Reports and related information pertinent to the technical aspects of fuels for internal combustion engines used in ground vehicles. The Truck and Bus J1616 Task Force has been formed under the committee's direction. Participants in the SAE Fuels Technical Committee include OEMs, suppliers, consulting firms, government and other interested parties.
|2010-01-2112||Elemental Composition Determination and Stoichiometric Air-Fuel Ratios of Gasoline Containing Ethanol|
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