SELF-IGNITION OF SOLIDS WITH DIMINISHING REACTION-RATES - EXACT COMPARISON BETWEEN THE RESULTS PREDICTED USING TIME-DEPENDENT AND SURFACE-OXYGEN ABSORPTION-DEPENDENT REACTION-RATE

In this paper, two comparisons between the two types of rate expressio ns (i.e. time and surface-oxygen absorption dependence) are provided t o answer an important remaining fundamental question from an earlier n umerical study by us in 1986. The time-dependent model appears to give a longer time-to-ignition than that predicted by another model type. It is concluded that the two types of chemical rate expressions give i nherent differences between their predictions of self-ignition. It is very important to use the conceptually correct model, i.e. the surface -oxygen absorption-dependent rate model, in practical prediction of ti me-to-ignition.