Effect of a Cocurrent Gas Flow on the Velocity and Concentration Limits of Combustion Wave Propagation in Granulated Ti + C + xAl2O3 Mixtures

Resumo

In this paper, we studied the effects of a cocurrent gas flow on the velocity and combustion limits of a granulated Ti + C mixture diluted with inert corundum granules. In the whole range of dilutions, an increase in the combustion rate was observed for the flow of active and inert gases. This effect is several times greater than that calculated based on the filtration combustion theory. Concentration combustion limits (75 wt %), the incomplete combustion of Ti + C granules, and the ratio of the combustion rates of the undiluted mixture and the mixture at the propagation limit (from 2 to 3) are well predicted by the percolation theory. The same combustion limit of concentration in the flow of inert and active gases and without flow indicates a percolation-phase transition as the reason for the cessation of combustion.