Propagation and Extinction of Various Mixtures of H2 / CO / CH4

Chemical Kinetic Uncertainty Minimization
through Laminar Flame Speed Measurements
Okjoo Park1, Peter S. Veloo2, Hai Wang1, Fokion N. Egolfopoulos1
Department of Aerospace and Mechanical Engineering
University of Southern California, Los Angeles, California 90089-1453, USA
Department of Mechanical and Aerospace Engineering,
Princeton University, Princeton, NJ 08544, USA
One of the critical elements towards accurate predictions of combusting flows is to characterize
and minimize the uncertainties associated with predictions of fundamental flame properties.
Although the chemical kinetics and flame chemistry of C1-C4 hydrocarbons have been
extensively studied, key uncertainties still exist. In this work, a large set of laminar flame speed
data systematically collected for C1-C4 hydrocarbons with well defined uncertainties were used
to illustrate how the well characterized flame speed data can be utilized to explore and reduce the
remaining uncertainties in a reaction model for small hydrocarbons. USC Mech II was used as a
sample model for that purpose. The method of uncertainty minimization using polynomial chaos
expansions (MUM-PCE) was employed to constrain the model uncertainty not only in flame
speed prediction but also in other flame properties. The work also explores the questions
concerning the type of hydrocarbon fuels that have the greatest impact on model uncertainty
reduction and the accuracy needed in the flame measurement to better facilitate model