Effect of Radiation Heat Loss and Ventilation on Dust Explosions in Spherical Vessels

The flame propagation through a coal dust-air mixture in a spherical vessel was studied by means of a one-dimensional, Arrhenius-type kinetics and quasi-steady model. The model includes the evaporation of the volatile matter of dust particles into a known gaseous fuel (methane) and the single-stage reaction of the gas-phase combustion. Effect of venting devices as safety idea and the radiation heat loss, as very affecting phenomenon on flame propagation speed, flame temperature and pressure were studied. The radiation heat losses occur between the reaction zone and the surrounding wall. Influence of dust concentration and dust volatility on dust explosion parameters has been analyzed. The pressure-time curves that are generated with this model show a good similarity with those measured in practice. The model can represent a useful framework to be employed in organic dust combustion. This research can be valuable in the development of alternative fuels; and it can be used by the fire safety and control industry.