A Study of Low Temperature Oxidation of N-heptane and Iso-octane in a Pressurised Flow Reactor

摘要

A turbulent pressurised flow reactor (PFR) has recently been established at the University of Melbourne for investigating hydrocarbon oxidation chemistry. This paper reports a study in this reactor on n-heptane and iso-octane at temperatures of 550-900 K, fixed equivalence ratio of 0.058 and a reactor pressure of 10 bar. Carbon monoxide is measured along the reactor as an indicator of the low temperature oxidation reactivity. The CO concentrations measured at a fixed resident time (0.21 s) show negative temperature coefficient (NTC) behaviour for both n-heptane and isooctane. Gas temperatures are also measured along the reactor and corrected for thermocouple radiative losses, which is then input into the Chemkin PFR model for kinetic simulation. Detailed combustion mechanisms from the literature are used in the modelling, reproducing the NTC behaviour and the CO formation at most temperatures tested. These results further validate the latest mechanisms of n-heptane and iso-octane.