Semenov's Model

Semenov developed a model for thermal explosions, which demonstrated the principles of the thermal ignition phenomenon in a quantitative way. The temperature T, of the reacting system is assumed to be constant and uniform across the whole volume of the system. The walls of the system and the external temperature are both assumed to be the same temperature T_a or T_ambient. This is shown in figure 1. This means that there is no gradual temperature gradient but a sudden change between inside and outside of the system.

Figure 1 - Temperature profile in the reacting system, as assumed by the Semenov theory