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Studies have been conducted with respect to the generation of fine‐disperse aerosols with the use of an explosive disperser model based on hydrodynamic shock tube. The physicomathematical model for the process of explosive dispersion with the aforesaid design is described [1]. The use of elements in the model design to produce cavitation bubbles under the action of shock wave and ensurance of slower outflow process of a water‐steam mixture makes it possible to obtain liquid disperse aerosols.The experimental results for aerosol disperse parameters and the processes of initiation and propagation of an aerosol cloud produced upon explosive dispersion of a variety of liquids and condensed powders are presented. Pressure values in the combustion chamber of the disperser, velocity of aerosol particles, and aerosol disperse parameters were obtained.The design of the explosive disperser with a nozzle, which provides favorable conditions for cavitation processes inside the dispersed liquid, is shown to allow the generation of a high dispersity aerosol (about 1–100 nm), which is essential for many practical problems. The function of distribution of such particles by size cannot be measured reliably and directly by methods available; however, indirect experiments (measurement of humidity when dispersing water) permit estimating the existence of particles in the aerosol with sizes below 1 μm in quantity of approx. 90 %.

The harmful effect on the health of superfine dust in industry is a serious problem. An especially important and complex task is the development of new methods for sedimentation of dust particles with a characteristic size of less than 10 μm. The solution offered by the authors involves a combined method of impact on industrial dust using highfrequency acoustic fields and spraying of a superfine water aerosol. Acoustic radiation sources are successfully applied to cleaning rooms from dust having fairly large particle sizes (10 μm and larger). The sedimentation of fine aerosols (particle diameter of 1-10 μm) is a more complicated challenge. The paper is devoted to substantiation of the acoustic sedimentation method for such aerosols. Good results were achieved when additional disperse phase was applied together with the ultrasonic source. Calculation results according to the mathematical model for coagulation and sedimentation, based on Smoluchowski's equation, taking into account evaporation of liquid droplets, are given. Results of the experimental and theoretical study of the processes of acoustic sedimentation of superfine aerosols are presented. Recommendations are offered for the use of sources of ultrasonic radiation and sprayers of water aerosol for optimum removal of dust from workplace air.

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