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We present a model that simulates the conventional tube-furnace experiment used for ign tion studies. The Distributed Activation Energy Model of Ignition accounts for particle-to-particle variations in reactivity by having a single preexponential factor and a Gaussian distribution of ac ivation energies among the particles. The results show that the model captures the key experimental observations, namely, the linear increase in ignition frequency with increasing gas temperature and the variation of the slope of the ignition frequency with oxygen concentration. The article also shows that adjustments to he model parameters permit a good fit with experimental data. NOMENCLATURE A 0 preexponential factor in Arrhenius rate constant of ignition (kg m-2 s- l) d diameter (m) E activation energy of ignition (kJ mol t) E0 mean of Gaussian distribution (kJ mol-1) h convective heat transfer coefficient (Wm-2 K) H e heat of reaction (J kg- t) k thermal conductivity (W m-t K) n reaction order of ignition with respect to oxygen Q heat generated or heat loss (W) R universal gas constant (8.314 × 10-3 kJ mo1-1 K-1) S external surface area of particle (m e) T temperature (K) y molar ratio of CO to CO