Experimental and Modeling Study of n-Propylcyclohexane Oxidation under Engine-relevant Conditions

The oxidation of n-propylcyclohexane (C9H18) was experimentally studied using the shock tube and the spherical bomb techniques. Both devices were heated in order to prevent wall adsorption. Ignition delay times, tau(i), of n-propylcyclohexane/O-2/Ar mixtures based on OH* and CH* radicals chemiluminescence have been measured behind reflected shock waves over a large range of temperatures (1250-1800 K), pressures (10-20 bar), and equivalence ratios (0.2-1.5). Laminar flame speeds at an initial temperature of 403 K and an initial pressure of 1 bar were also determined using a stainless steel spherical bomb for equivalence ratios between 0.6 and 1.75. The visualization of the flame was achieved using a Schlieren system coupled to a high-speed camera. Ail the results obtained were successfully modeled based on a detailed kinetic mechanism (110 species and 690 reactions) built using two models from the literature.