IGNITION AND FLAME QUENCHING OF QUIESCENT DUST CLOUDS OF SOLID FUELS.

Experiments have been carried out to study the influence of particle size, dust concentration, pressure, mass transfer number and oxygen/nitrogen ratio on quenching distance and minimum ignition energy of dust clouds of solid fuels. The solids chosen were aluminum, magnesium, titanium and carbon. Ignition was accomplished by using sparks whose energy and duration could be varied independently. The results of these tests show that particle size has a strong influence on the minimum ignition energy, the quenching distance and the optimum duration. It appears that both solid and liquid fuels may be treated as members of a single family.