Skeletal mechanism generation for surrogate fuels

Abstract

The Mechanism Automatic Reduction Software (MARS) implementation for chemical reaction mechanism reduction, with special emphasis on skeletal reduction using the directed relation graph with error propagation and sensitivity analysis (DRGEPSA), is developed and demonstrated with examples for three hydrocarbon components, n-heptane, iso-octane, and n-decane, relevant to surrogate fuel development. DRGEPSA integrates two previously developed methods, directed relation graph-aided sensitivity analysis (DRGASA) and directed relation graph with error propagation (DRGEP), by first applying DRGEP to efficiently remove many unimportant species prior to sensitivity analysis to further remove unimportant species, producing an optimally small skeletal mechanism for a given error limit. It is illustrated that the combination of the DRGEP and DRGASA methods allows the DRGEPSA approach to overcome the weaknesses of each, specifically that DRGEP cannot identify all unimportant species and that DRGASA shields unimportant species from removal. Skeletal mechanisms for n-heptane and iso-octane generated using the DRGEP, DRGASA, and DRGEPSA methods are presented and compared to illustrate the improvement of DRGEPSA. Two skeletal mechanisms for n-decane generated using DRGEPSA, one covering a comprehensive range of temperature, pressure, and equivalence ratio conditions for autoignition and the other limited to high temperatures, are presented and validated. Both mechanisms are further demonstrated to well reproduce the results of the detailed mechanism in perfectly-stirred reactor and laminar flame simulations over a wide range of conditions.

BibTeX

@mastersthesis{Niemeyer:2010,
    Author = {Kyle Evan Niemeyer},
    Month = jan,
    School = {Case Western Reserve University},
    Location = {Cleveland, OH},
    Title = {Skeletal mechanism generation for surrogate fuels},
    Year = {2010}
}