E.1.4. 2-Component Model, with a Focus on Soot Using Pseudo-Gas Model

The Diesel_2comp_191sp__soot-pseudo-gas.cks chemistry set consists of a 191 species gas-phase mechanism. The mechanism represents diesel with the 2-component n-decane/ 1-methyl naphthalene (AMN) as the fuel surrogate. The focus of this chemistry set is on accurate soot modeling from combustion in diesel engines. This chemistry set represents "soot" as a gas-phase species.

The pseudo-gas soot model includes soot nucleation pathways through benzene and phenyl, and growth dominated by HACA pathways. It also includes soot oxidation through O2 and OH.

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

  1. Equivalence ratios of 0.5-3.

  2. Pressures of 1-150 bar.

  3. Temperatures of ~650 K and higher.

  4. EGR of 0%.

  5. This mechanism was assembled for a cetane number of 55, with a composition of 33 wt% AMN / 67 wt% n-decane.

This mechanism has been reduced from the Diesel_PAH_NOx mechanism from the Ansys MFL that contains more than 5000 species. As documented in the Ansys Model Fuel Library (MFL) Manual,the mechanism has been thoroughly validated against fundamental experimental data for the operating conditions of interest in engines. The mechanism was reduced from this comprehensive "full" mechanism using Ansys Chemkin Reaction Workbench software [32], for the conditions listed above.

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

  1. Soot-precursor species:

    1. acetylene (c2h2).

    2. benzene (c6h6).

    3. phenyl (c6h5).

  2. CO.

  3. NOx species NO and NO2.

The species names in the chemistry file for the fuel species are:

  1. n-Decane is nc10h22.

  2. AMN is a2ch3.