A NEW ROUTE OF CHAOS IN GASLESS COMBUSTION

It has been observed that the gasless combustion of thermites can proceed in a variety of nonsteady propagation modes that range form periodic to chaotic in character. While the nature of the transition from steady to nonsteady, but periodic, combustion is now well understood, the various mechanisms that lead to more complex (e.g., chaotic) modes of burning are is not. However, it has been shown that mode interactions which arise after the neutral stability boundary is crossed do lead to combustion waves that exhibit more complicated spatial and temporal behavior. In the present work, we foucus on the case of temporally resonant mode interactions and show how such interactions can provide a new route to chaos in gasless systems. The resulting character of the propagating combustion wave is that of chaotic, multiple-point combustion, in which one may observe the random movement of hot spots that appear, disappear and reappear on the sample surface, as reported in recent experiments. Various quantitative measures of this attractor are then presented.