Home – Home – Jornals – Chemistry for Sustainable Development 2005 number 2

Mathematical models of connecting materials using a mixture of exothermal composition with inert filler in the regime of thermal explosion and in the regime of combustion are proposed. The first problem is formulated as thermal inflammation in a vessel with thick walls, the second one as the propagation of the front of exothermal reaction in a slit between two thick plates. In general, the addition of an inert filler to the connecting mixture causes an increase in inflammation time, a decrease in temperature and rate of reaction, which coincides with the known experimental data. Within a definite region of the model parameters, numerical investigation of the inflammation problem revealed different regimes of inflammation: thermal explosion and a slow transformation under weakly changing temperature. When investigating the problem of reaction propagation in a slit, also different regimes of transformation with variations of thermal properties of the substances were discovered. The region of parameters in which the self-sustaining regime of transformation occurs was found. For real technologies, low-temperature synthesis regimes are of interest, because in this case thermal strain decreases.