The purpose of the work is to determine the effect of slag on the processes of mixing the steel melt in the ladle during its bottom purge. The study by physical modeling was carried out on a transparent bucket model with its bottom purge without slag layer and, if any, it was present. Water was used as the liquid of the metal, and slag was sunflower oil. The bath was washed with air at various costs. Controled the thickness of the slag layer and the surface area of the metal surface from it. The level of conductivity of a water bath was determined depending on the variables. A slight decrease in the electrical conductivity of the melt mist (water) in the presence of slag is observed, as well as an increase in the thickness of the slag layer and the surface area of the melt surface with increasing air flow. The factors which can be applied for the calculation of hydrodynamic processes during the processing of steel on the "ladle-furnace" installation, taking into account the slag component, are revealed. It is shown that when the air flow increases, the diameter of the water released from the slag (oil) increases, and when the volume of the latter is stored, the thickness of its layer increases. The expediency of continuation of researches by cold physical modeling of hydrodynamics, heat and mass transfer with and without slag is shown, which will allow them to be taken into account in hot modeling and in industrial conditions.