ILDMs of higher hydrocarbons and the hierarchy of chemical kinetics

It is well known that the combustion of higher hydrocarbons is governed by a hierarchical structure of the underlying detailed reaction mechanisms. This allows (at least for high-temperature kinetics) the construction of combustion mechanisms for higher hydrocarbons based on the H-2, CO, and C-1-C-4 oxidation mechanisms by adding reactions for the decomposition of the higher hydrocarbons. In this work, we show how this hierarchical structure is reflected in simplified kinetic schemes based on intrinsic low-dimensional manifolds (ILDMs). An analysis of the dynamical behavior of the chemical system reveals that (at least for low dimensions) the dynamics can be represented by generic ILDMs which do not depend on the specific fuel considered. This allows the construction of ILDMs of higher hydrocarbons based on existing ILDMs of much simpler reaction mechanisms for C-1-C-2 or C-1-C-4 chemistry. Examples are shown for combustion of syngas, methane, iso-octane, n-dodecane, and other fuels. They verify the approach. The method can, however, be applied to a variety of other combustion systems, too.