Critical and Transition Conditions for Ignition of a Carbon Particles Dust Cloud in an Adiabatic Confined Vessel

Abstract

Ignition and explosion characteristics of a carbon particles dust cloud in an adiabatic confined vessel have been investigated analytically and numerically in this study. The critical conditions as well as the transition conditions (at which criticality disappears) have been presented in mathematical expressions. Uniform particle temperature has been assumed in this work. The steady-state and unsteady-state solutions for the problem using the well-known definition of criticality has been offered for ignition of carbon particles cloud in diffusion, kinetic, and diffusion-kinetic regimes. It was found that the ignitability characteristics of carbon particles such as critical ignition temperatures and ignition delays are affected by the initial gas (oxidizer) temperature as well as the concentration of carbon particles in a gas. The temperature- time histories of both carbon particles and gas as well as the variation of particle diameter with time from the numerical study are presented and discussed.

Keywords:

• Critical and transition conditions
• Thermal explosion
• Two-phase media