A statistical approach to determine the autoignition temperature of dust clouds

The aim of this work has been to propose a new definition of the autoignition temperature that is based on the ignition probability concept. AIT is defined as the temperature at which the ignition probability is lower than a given threshold. In order to arrive at this definition, the dependence of the cloud Autoignition probability on the temperature in the temperature interval close to AIT needs to be investigated. In the present experiment, Lycopodium and Wood Char were used to carry out the tests. The Ignition probability vs temperature relationship in the range in which the probability varies from zero to one (we have called such a range probability escalation interval, PEI) has been determined and the resulting experimental data have been interpreted by means of an appropriate statistical model. Experimental data can, in fact, be used to identify the threshold below which the ignition probability is lower than a suitably predefined level with prescribed confidence, thus providing a more solid ground on which the definition of the AIT could be based.