On the possible coexistence of two different regimes of metal particle combustion

The coexistence of two regimes of aluminum (Al) particle combustion is discussed. A slower regime occurs at a low energy accommodation coefficient (EAC) and is usually observed in Al combustion experiments. A faster regime at high EAC is also possible. The combustion enhancement observed for pre-treated Al particles can be interpreted as a switch from the slower combustion regime to the faster regime. The value of EAC is controlled by the thermionic emission of electrons. A relationship between Al particle pre-treatment and the work function, which governs the thermionic emission, and, therefore, the EAC, is a subject of further studies.