Development of a reduced mechanism for ethanol using directed relation graph and sensitivity analysis

摘要

Numerical simulations involving detailed kinetic reaction mechanisms of combustion for conventional fuels are associated with computational costs prohibitive and, therefore, a lot of effort for obtaining reduced kinetic mechanisms has been observed. Among the known strategies, the Directed relation graph (DRG) method and the sensitivity analysis have proven to be very powerful tools, in addition to the traditional and efficient assumptions of steady-state and of partial equilibrium. The present work proposes a reduction strategy with these techniques for reduction of a mechanism for ethanol. Based on a mechanism of 377 reactions among 56 reactive species a skeletal mechanism, consisting of 24 species and 26 reactions, was obtained through the application of the DRG method and performing a sensitivity analysis. Using the assumptions of partial equilibrium and steady-state, which are justified by an asymptotic analysis, an additional reduction leads to a reduced mechanism of ten steps. Results of the new mechanism for a jet diffusion flame compare favorably with data found in the literature. The computational cost for simulation of jet diffusion flames with the reduced model is one order of magnitude less than necessary in the complete model, which is the principal contribution of this work.