Ignition of Combustible Forest Materials by a Radiant Energy Flux
A. M. Grishin, V. P. Zima, V. T. Kuznetsov, A. I. Skorik
Tomsk State University, Tomsk 634050, fire@fire.tsu.tomsk.su
Abstract
The paper reports results of experimental ignition of litter layers consisting of needles of cedar, pine, and firtree, birch leaves, lichen Cladonia, and moss Pleurozium shreberi. It is established that the moss is ignited faster than the other combustible forest materials. It is shown that with equal moisture contents, the ignition times of needle litter from different trees are identical within the experimental error, and for litter of birch leaves, the ignition time is shorter than that for litter of coniferous trees. This difference is found to be due to differences in the interaction of the radiant flux with litter layers of needles and leaves. Minimum values of the ignition heat pulses for needle and leaf litter layers are estimated for various heatflux densities. These values tend to a minimum for a heatflux density of 0.50.8 MWm2. P. 24-29
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