Movement of water droplets in a layer of thermally decomposable forest fuel

This article contains results of an experimental study of the process of droplets gravitating in a layer of a typical forest fuel during its thermal decomposition. Also similar experiments were carried out in conditions of moderate temperature conditions (about 300 K). Pine needles were considered as a material for study. The initial droplets' volume was varied from 90 to 900 μL. After analysis of experimental results we established the depths, on which water droplets can penetrate into the layer of forest combustible material (FCM). The characteristic velocities of water droplets' motion at different distances from the FCM surface were calculated. Also we determined the fraction of the mass of water consumed in the FCM layer for vaporization and cooling of the material to temperatures below the values corresponding to thermal decomposition.