Flame Tip Propagation with Assisted Flow along Fuel-soaked Ground

Abstract

The propagation of a flame tip in an assisted flow along the high-temperature ground soaked with high-volatile liquid fuel was studied experimentally from the point of view of a fundamental study on the fire hazard prevention in many fuel spill accidents. The effects of flow velocity on the flame tip propagation and on the motion of flammable gas layer were investigated experimentally. The study revealed the interesting and characteristic dependence of the propagation velocity of the flame tip on the flow velocity, which is classified into three regions by the ratio of the flow velocity about 1 mm above the ground surface to the flame propagation velocity with no surrounding airflow. The flame tip blows off and no flame propagation occurs when the ratio is over about 1.5, which agrees with the blow-off of spreading flame in an opposed flow, described in detail in our previous study. The flame tip propagation in an assisted flow strongly depends on the formation of a flammable gas mixture downstream of the flow.