Development of a model of atmospheric aerothermodynamics for the study of dusting processes at tailings dumps using COMSOL software

An overview of studies of aerothermodynamics and atmospheric pollution at mining facilities using computational fluid dynamics software systems (CFD modeling) has been presented. Both specialized and non-specialized software are marked. The review focuses on the studies performed using the FLOWVISION, ANSYS FLUENT and COMSOL software codes. An aerothermodynamic model of the atmosphere is described in which the equations of dynamics in the incompressible fluid approximation are supplemented by the heat transfer equation and the parameters of Coriolis, convection (buoyancy), background stratification and radiation flux. The necessary modifications in the COMSOL software are described, which make it possible to carry out studies of atmospheric aerothermodynamics under various atmospheric conditions. A two-dimensional CFD model of the atmosphere has been built and tested on a simplified representation of the tailings dump. At a fixed wind flow velocity of 5 m/s and variations in the background stratification parameter (from –0.05 to +0.05 °C/m), numerical experiments have been performed and the calculation results have been analyzed. Differences in the aerodynamic parameters of the flows and the spatial distribution of temperature under different atmospheric conditions are noted. Estimates of the dynamic velocity at the dusting height and the vertical mass flux using the empirical dependence of the dusting intensity are performed. The analytical dependence of the vertical mass flux as a function of the stratification parameter is discussed. The asymmetry (relative to the neutral state of the atmosphere) of the magnitude of the vertical mass flux in comparison with the unstable and inversion states is shown. In stable atmospheric conditions, the magnitude of the vertical flux of the dust mass, and hence the pollution of the atmosphere downstream, will be noticeably higher than in unstable states.