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Title: Skeletal reaction models for methane combustion
A local-sensitivity-analysis technique is employed to generate new skeletal reaction models for methane combustion from the foundational fuel chemistry model (FFCM-1). The sensitivities of the thermo-chemical variables with respect to the reaction rates are computed via the forced-optimally time dependent (f-OTD) methodology. In this methodology, the large sensitivity matrix containing all local sensitivities is modeled as a product of two low-rank time-dependent matrices. The evolution equations of these matrices are derived from the governing equations of the system. The modeled sensitivities are computed for the auto-ignition of methane at atmospheric and high pressures with different sets of initial temperatures, and equivalence ratios. These sensitivities are then analyzed to rank the most important (sensitive) species. A series of skeletal models with different number of species and levels of accuracy in reproducing the FFCM-1 results are suggested. The performances of the generated models are compared against FFCM-1 in predicting the ignition delay, the laminar flame speed, and the flame extinction. The results of this comparative assessment suggest the skeletal models with 24 and more species generate the FFCM-1 results with an excellent accuracy.  more » « less
Award ID(s):
2042918 2152803
PAR ID:
10545913
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Fuel
Volume:
357
Issue:
PA
ISSN:
0016-2361
Page Range / eLocation ID:
129581
Subject(s) / Keyword(s):
Methane-air combustion Skeletal model Local sensitivity analysis Forced optimally time dependent modes High-pressure
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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