Comparative analysis of detailed and reduced chemical models of N-dodecane

For the purposes of combustion analysis, n-dodecane is used as the surrogate or a surrogate component for biodiesel and jet fuel. In order to capture kinetic effects in computational combustion, detailed and reduced models of n-dodecane are therefore used. This paper presents a comparative analysis of selected detailed chemical kinetic models of n-dodecane as well as reduction of these detailed models to more compact skeletal versions. The selected models are compared based on their ability to predict ignition phenomena. Measured ignition delay times from the literature are used as references. Both low- and high-temperature ignition simulations are considered. To further facilitate future computational combustion analysis, the detailed models are reduced using the Alternative Species Elimination (ASE) approach reported by Akih-Kumgeh and Bergthorson (Energy & Fuels, 2316-2326, 2013). The resulting skeletal models are compared in terms of their retained species, ranked species sensitivities, and kinetic parameters of the key reactions. Furthermore, within the framework of this paper, another model reduction technique is explored. The aim of this method is to further decrease model reduction time since this is often considered as a weakness of the otherwise effective ASE method. The resulting models from this exploratory reduction approach are compared with those obtained from the ASE method in terms of species retained and the accuracy with which combustion properties from the detailed models are predicted. Further chemical kinetic analysis of the reduced models is carried out with the aim of explaining observed similarities and differences.