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We have made experimental studies of the processes of deformation of drops (of size up to 6 mm) of three liquids with different physical properties (water, ethanol, kerosene) in motion in a gaseous medium (air) with velocities of up to 5 m/s. The most typical forms of drops have been distinguished, and the cyclic character of their change in traveling in a gaseous medium to distances of up to 1 m has been established. The characteristic "deformation cycles" in the process of motion have been determined, and the time intervals of the form change within each "deformation cycle" have been established. The maximum deviations of drop sizes from the initial ones have been calculated, and the infl uence of their sizes and velocities on the basic characteristics of the deformation have been determined.Introduction. By now a fairly large aggregate of knowledge [1-10] of the mechanisms of deformation, fragmentation, and coagulation of drops of various liquids in their motion in gaseous media has been accumulated. Complex confi gurations of liquid drops under these conditions have been established [3][4][5][6][7]. However, published results of investigations with numerical values of the parameters characterizing these processes are not many. Moreover, it is not infrequent that results of experiments performed by different authors differ markedly in both numerical values and conclusions drawn [1][2][3][4][5]. With the advent of high-speed measuring complexes (in particular, cross-correlation cameras and pulsed lasers), it became possible to analyze the process of motion of liquid drops in a gaseous medium with a high time discretization of the processes (up to units of nanoseconds). For example, we can point to the results of experimental investigations [11][12][13] of the mechanisms of highspeed fragmentation and coagulation of liquid drops as they enter a gas fl ow with parameters varied over fairly wide ranges. Of interest are experimental investigations with the use of cross-correlation cameras and pulsed lasers of the deformation mechanism of liquids used in various branches of industry (for example, water, ethanol, kerosene) aimed at determining the numerical values of the main parameters of these processes. At Weber numbers above 7 in the "gas fl ow-liquid drop" system the investigated processes are characterized, as a rule, by intense fragmentation of drops [7][8][9]. This complicates considerably the analysis of the deformation mechanisms and, therefore, it is expedient to perform experiments at subsonic (less than 5 m/s) velocities of drops.The aim of the present work was to determine experimentally the characteristics and establish the deformation mechanisms of water, ethanol, and kerosene drops in their motion in a gaseous medium with subsonic velocities.Experimental. The experimental facility is schematically represented in Fig. 1. As for the basic instrumentation, the facility is analogous to that used in investigating the evaporation of water drops in a high-temperature (above 1000 K) gaseous medium [14][15][...

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Fire protection is a basic safety issue for all categories of buildings. The criteria for effective fire suppression and the characteristics of extinguishing systems in insulated areas depend on a combination of factors. The main influences include the type of combustible material, ambient temperature, type of spray extinguisher, air inflow and outflow conditions, and space geometry. This article analyzes the most widely used fire-extinguishing technologies in different locations. The main aspects of using the pulsed delivery technology of extinguishing liquid are considered. Based on the analysis of publications from the last decade, it is possible to develop intelligent systems for recording fires and extinguishing fires in the premises.