E.2.1. 1-Component Fuel Model for Spark-Ignition Simulations Without Knocking

The Gasoline_1comp_49sp.cks chemistry set consists of 49 species. It represents gasoline with the single-component iso-octane as the fuel surrogate. The mechanism captures the pathways necessary for only the high-temperature reactions, and focuses only on capturing emissions from combustion in spark-ignited engines. Since this mechanism does not include low-temperature reaction pathways, it cannot be used for predicting knocking.

The mechanism has been validated against fundamental data for the following conditions:

  1. Equivalence ratios of 0.4-3. This range is to capture both GDI and port-fuel injection engine local environments.

  2. Pressures of 1-100 bar.

  3. High-temperatures of ~1200 K and higher.

  4. EGR of 0-40%.

This mechanism has been reduced from a larger gasoline kinetics mechanism consisting of ~2600 species, which has been thoroughly validated against fundamental experimental data for the operating conditions of interest in engines, under the Model Fuels Consortium [20]. The Ansys Model Fuel Library (MFL) Manual includes the mechanism validation plots. The mechanism was reduced from this comprehensive "full" mechanism using the Reaction Workbench software [32], for the conditions listed above.

For the emissions, the following species predictions are expected to be accurately predicted:

  1. CO.

  2. NOx species NO and NO2.

  3. Soot-precursor species acetylene (C2H2).

The species name in the chemistry file for the fuel species iso-octane is ic8h18.