A MODEL OF COOLING A FLAT SURFACE WITH AN IMPACT JET OF EXTINGUISHING AGENT IN CASE OF A FIRE

Analysis of problems of cooling a roof of vertical steel tanks. The problem of the complex effect of the coolant flow mode, the distance from the cutoff of the fire barrel to the cooled plane, and the duration of the process at the braking point of an unsteady axisymmetric impact jet is posed. An analytical solution of the energy equation is obtained, formulated as a criterion equation. It is established that at significant distances between the nozzle section of the fire barrel, when Fr < 1, the intensity of heat exchange between a freely falling impact jet of extinguishing agent becomes more significant. It is established that at Fr > 1, the intensity of heat exchange does not depend on the magnitude of this distance, and in other cases it increases. It is stated that for a dispersed jet structure, the average heat transfer characteristics increase significantly for a short pulse duration.