On the limits of flame propagation in a dusty gas

The limits of flame propagation in a gas with suspended inert particles in the presence of external heat removal have been studied. The mathematical model used is based on an unsteady heat-diffusion two-temperature model of gas combustion in the presence of inert particles. The problem is solved by a numerical method. A parametric analysis was performed, and critical values of the parameter that characterizes external heat removal are obtained. Dispersed-phase parameters are determined for which the two-temperature nature of the medium is insignificant. For this case, an analytic estimate for the critical parameters of flame quenching was obtained. At the moment of flame quenching, the normal flame-propagation velocity in a dusty, gas decreases by a factor of $\sqrt{e}$ compared with the flame velocity in the dusty gas under adiabatic conditions.