ASTM-E659 standardized test analysis and results for Synthetic Paraffinic Kerosene

Improvements on ASTM-E659 apparatus are used to investigate autoignition (AIT) of a Synthetic Paraffinic Kerosene (SPK). The apparatus injection system has been automated, and the temperature acquisition system has been improved to reduce variability due to human factors. The SPK was compared with a Jet A standard, POSF4658. The two fuels have a similar range of combustion behaviors but the SPK shows a lower AIT and lower effective activation energy than Jet A. A statistical analysis is proposed to quantify the likelihood of ignition for a range of injected fuel volumes and types of ignition events. We observe that luminous ignition (Mode I) and non-luminous cool flame (Mode III) both result in a vigorous reaction and comparable peak temperatures. This highlights the importance of using the temperature signal to detect ignition instead of relying only on flame visualization. Surveys of the temperature distribution inside the hot vessel demonstrate that a single point measurement is not sufficient to characterize the temperature and that subtle changes in the assembly of the apparatus can significantly alter the temperature distribution and the measured AIT.