A comprehensive skeletal mechanism for the oxidation of n-heptane generated by chemistry-guided reduction

Journal Article · Mon Dec 15 00:00:00 EST 2008 · Combustion and Flame

DOI:https://doi.org/10.1016/J.COMBUSTFLAME.2008.05.007· OSTI ID:21125487

Zeuch, Thomas ^[1]; Moreac, Gladys ^[2]; Ahmed, Syed Sayeed; Mauss, Fabian ^[3]

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1. Institut fuer Physikalische Chemie, Tammannstrasse 6, 37077 Goettingen (Germany)
2. Renault, 1, avenue du Golf, 78288 Guyancourt cedex (France)
3. Lehrstuhl fuer Thermodynamik und Thermische Verfahrenstechnik, Sielower Strasse 12, 03044 Cottbus (Germany)

Applied to the primary reference fuel n-heptane, we present the chemistry-guided reduction (CGR) formalism for generating kinetic hydrocarbon oxidation models. The approach is based on chemical lumping and species removal with the necessity analysis method, a combined reaction flow and sensitivity analysis. Independent of the fuel size, the CGR formalism generates very compact submodels for the alkane low-temperature oxidation and provides a general concept for the development of compact oxidation models for large model fuel components such as n-decane and n-tetradecane. A defined sequence of simplification steps, consisting of the compilation of a compact detailed chemical model, the application of linear chemical lumping, and finally species removal based on species necessity values, allows a significantly increased degree of reduction compared to the simple application of the necessity analysis, previously published species, or reaction removal methods. The skeletal model derived by this procedure consists of 110 species and 1170 forward and backward reactions and is validated against the full range of combustion conditions including low and high temperatures, fuel-lean and fuel-rich mixtures, pressures between 1 and 40 bar, and local (species concentration profiles in flames, plug flow and jet-stirred reactors, and reaction sensitivity coefficients) and global parameters (ignition delay times in shock tube experiments, ignition timing in a HCCI engine, and flame speeds). The species removal is based on calculations using a minimum number of parameter configurations, but complemented by a very broad parameter variation in the process of compiling the kinetic input data. We further demonstrate that the inclusion of sensitivity coefficients in the validation process allows efficient control of the reduction process. Additionally, a compact high-temperature n-heptane oxidation model of 47 species and 468 reactions was generated by the application of necessity analysis to the skeletal mechanism. (author)

• OSTI ID: 21125487
• Journal Information: Combustion and Flame, Vol. 155, Issue 4; Other Information: Elsevier Ltd. All rights reserved; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
HEPTANE
COMBUSTION
DECANE
TEMPERATURE RANGE 0400-1000 K
FLAMES
IGNITION
MIXTURES
SENSITIVITY
VALIDATION
SENSITIVITY ANALYSIS
DIESEL ENGINES
PRESSURE RANGE KILO PA
PRESSURE RANGE MEGA PA 01-10
VARIATIONS
VELOCITY
Chemical lumping
Skeletal mechanism
Reduced mechanism