Mechanism Of Smoke Generation In A Flickering Pool Fire

Abstract

Smoke generation process in a flickering pool fire was examined to understand the effect of hydrodynamic properties of the flame on smoke generation. A detailed observation was performed in a toluene pool fire with diameter of 90 mm. Smoke generation occurred when flame flickers with a mushroom-like flame appearance. As the mushroom-like flame appears, gas flow moves almost horizontally and parallel to the flame front just under the mushroomlike flame, and at the same time a large amount of smoke is released from the flame. The residence time of soot particle in the soot production region is increased by the flickering motion of the flame. Soot growth is enhanced by the increase in the residence time. The increased radiative heat loss by the grown soot particles might result in flame extinction and a large amount of smoke is released from the flame. The calculation of the velocity induced by thermophoretic force was also performed. It is found that the thermophoretic force affects on the smoke generation process in a flickering flame.