Mathematical Model of Calculation of the Surface Intensity of Feed of a Coolant in Aviation Extinguishing of Ground Forest Fires

Results of mathematical modeling of the water concentration of the underlying surface during the aviation extinguishing of ground forest fires of varying intensity have been given. In extinguishing a high-intensity ground fire, droplets entering the zone of combustion evaporate in the flame. Therefore, no wetting of the underlying surface occurs in the combustion zone. With increase in the initial velocity of the droplets, the left boundary of the zone of wetting shifts to the seat of fire, thus raising the efficiency of the use of water in the process of fire extinguishing. In extinguishing a moderate-intensity ground fire, two coverage zones are formed on the windward and leeward sides of the seat of fire, and also the region of intense evaporation between them. Boundaries between these regions are only determined by the intensity of the fire and by the geometric characteristics of the combustion zone. Investigation of the influence of conditions for the formation of a gas–droplet cloud on the process of extinguishing a low-intensity ground fire shows that at a small dropping height, a single continuous coverage zone is formed. In this case its length is determined mainly by the length of the primary cloud and to a lesser extent by the initial droplet velocity and the distribution of the wind velocity in the atmosphere.