Open AccessRelevance of study is caused by the search for effective schemes and devices to intensify air exchange of open pits, which is, substantially, worsen with increasing depth of pits and intensity of mining operations. To implement air exchange of pits the scheme of ventilation with simultaneously used device for aeration of pits (DAP) is offered. DAP represents the inclined profiled blades on the support, which are set on the top platform of the pit leeside near the edge (patent-protected useful DAP model) and based on the turbo-propeller aviation engines pit fan (PF) before it. The associated works in the field concerned consider general development factors of free and semi-limited jets, being developed near a flat surface that is different from their development in the conditions of limiting quarry out space with various parameters (overall slope angles, depth, benches at the edges, etc.). The work objective was to study and define the structure and optimal arrangement of PF in respect to DAP and estimate efficiency of using DAP+PF scheme through modelling in a wind tunnel by criterion of average speed of aerial currents in the pit, using a DAP+PF scheme of ventilation.
Features of development of aerial currents in pits with various parameters are analysed. Consistent patterns of speed distribution of in semi-limited jet currents are determined. It is proved that the air amount involved in air exchange increases by 8-10 times in comparison with the case with one PF used. The offered air exchange scheme of the quarry out space can be used both for an intensification of airing pit, and for its ventilation. The received study results of aerial current aerodynamics can be used in designing air exchange of pits according to the offered scheme.