Experimental Research on Burning Rate of Methane Pool Fires by Insulation and Crosswinds

Abstract

In order to study the effect of wall insulation conditions and different airflows on burning rate of pool fires, a small-scale ethanol pool fire was conducted experimentally under three pool diameters and a certain lip height in a wind tunnel. The results showed that the non-monotonic mass loss rate decreases first and then increases with the increase of crosswinds at a certain lip height. The burning rate increases with the increased pool diameter of the non-insulated pool fires, while an opposite trend of burning rate was found in insulated pool fires at the same sizes. The dimensionless characteristics of Richard number presents the variation relationship between the buoyancy force and momentum during different airflows. The insulated liquid pool showed a higher burning rate than that in a non-insulated pool with the characteristic parameter of reciprocal of Richard number less than 2. With the value of Richard number continue increased, the burning rate in the insulated pool fires decreased due to the difference between the increased crosswind and heat transfer. The mass loss rate of pool fires without insulation increased with the increase of pool diameter, while an opposite trend was found in insulated pool fires at the same size. The experimental data supported to establish a ratio coefficient of burning rate with or without insulation under different crosswinds.