Effect of mechanochemical activation and microgrinding on the intensity of combustion of solid fuel

Abstract

The effect of mechanochemical activation and microgrinding on the intensity of combustion of solid fuel particles was studied. As applied to the rapid process of the combustion of solid fuel particles, mechanochemical activation was simulated within the framework of nonequilibrium thermodynamics with the expansion of the classical dependence of the local entropy of state of the reacting system on relaxation phenomena. The dependences of the intensity of burning (mass loss time) of deformed organic solid fuel particles on the relaxation processes of the momentum transfer of their excited states and on the mutual orientation of shear stresses and the first difference in normal stresses (a steric factor), which compensate for temperature power consumption, were established. The rate of combustion is determined by the size of burning particles, their density, and a ratio between the elastic and dissipative scattering of mechanical energy in the particles, which increases the diffusion mobility of burning components with a decrease in the time of their burning. The ranges of variation in the parameters of the burning system in which the particle size or mechanoactivation exerts a considerable effect on the combustion time of fuel particles were recognized. Experiments on the torch combustion of coal-dust fuel as the cumulative combustion of its particles confirmed the effect of mechanoactivation.