At discharge of water from aircraft in a forest fire zone, the most complicated (for predicting the scales of influence on flame burning and thermal decomposition of materials) factor is the influence of wind. It consists not only in the change of velocities and directions of combustion front propagation, but also changes trajectories of fire extinguishing compositions in the gas medium. The transformations of the surface of freely falling volumes of water in the form of drops, jets, and arrays have a decisive influence on combustion suppression. As a result, it is often difficult for firefighters to cover completely the pyrolyzing and burning forest surface area with water or other fire extinguishing compositions. This paper presents the results of experimental research of the conditions and characteristics of the shift of trajectories of moving fluid fragments due to the influence of wind. The experiments were performed in the laboratory with varying air flow rate (to reproduce the wind factor) in the range from 0 to 7 m/s. As a result, the characteristic dependences of aerosol cloud droplet displacement and aerosol trace area on the air flow velocity have been determined. The correlations of limiting distances, to which water fragments were carried away, and airflow velocities have been established for different water array volumes. The obtained results of experimental studies are the basis for the creation of physical and mathematical models that enable predictive calculations of the influence of a number of factors on the characteristics of the entrainment of liquid fragments from the combustion localization zone.
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