Characterization of the Autoignition of Single Droplets of Fischer-Tropsch Fuels and Development of Surrogates

Abstract

The autoignition behavior of single droplets of synthetic fuels produced by the Fischer-Tropsch process, such as GTL-Diesel and GTL-Kerosene, is the main focus of this study. For this, experiments are carried out under microgravity and normal gravity conditions with single droplets with an initial diameter of 0,7 mm in a high-temperature high-pressure chamber. Ignition delay times are determined for ambient pressures between 0,1 MPa < p < 1 MPa and ambient temperatures between 550 K < T < 950 K with the aid of a Michelson interferometer setup. The experimental data is fitted with two-term Arrhenius-type functions that represent the two main reaction mechanisms, the cool and hot flame. Furthermore the development of suitable surrogate fuels for these fuels is performed and the selection and formulation procedure for the components is shown. Surrogate fuels enable numerical calculations with detailed chemical reaction kinetics. The obtained data on the characterization of the aforementioned fuels is compared with data of related fuels, such as their mineral variants and other surrogates.