The problem of estimating the level of air pollution in the working areas near the coal pile is considered. The task is to develop a CFD model that allows to predict the level of air dust pollution, taking into account the process of wetting the surface of the coal pile. To model the process of coal dust transfer in the air, a twodimensional mass transfer equation is used, which takes into account coal dust transfer due to convection and diffusion. The Navier-Stokes equations are used to calculate the air flow field near the coal pile. Finite-difference schemes of splitting are used for numerical integration of modeling equations. Computer code is developed on the basis of created CFD model. The developed code can be used to analyze the effectiveness of the coal surface wetting to reduce dust pollution of work areas near coal piles. The results of a computational experiment are presented.

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Intensive environment pollution takes place during coal transportation in open wagons. Emission of coal dust from the coal wagons cause contamination of atmosphere and territory adjacent to the railway track. Different ways to reduce coal dust emission from the wagon are used in the world. Unfortunately, in Ukraine, this problem is far from solution and there is no serious research work in this field. The aim of this work was laboratory study of coal dust emission from the wagon model which had different barriers installed on the wagon. Laboratory experiments were carried for coal wagon without barrier and for coal wagon which had barriers of two types. Barrier of the first type had downwind wing. Barrier of the second type had upwind wing. The contamination zones, concentration near the model were studied. The obtained results illustrate that installation of barriers influence intensity of transport corridor contamination. Also a numerical model was developed to estimate wind flow and coal dust dispersion from the coal wagon. Equation of potential flow and equation of coal dust dispersion were used. Implicit difference schemes of splitting were used for numerical simulation of governing equations. Results of numerical experiment, which were performed, are presented.

A computational model to simulate ventilation of a dead-end mine working with line brattice has been developed. To solve fluid dynamics problem, i.e. to compute flow pattern, model of inviscid flow has been used. That allows to compute quickly air flow pattern. To simulate dust dispersion in the dead-end mine working with brattice twodimensional equation of mass transfer has been used. Numerical integration of Laplas equation for the velocity potential has been carried out using Samarski two steps difference scheme of splitting. Proposed CFD model allows quick computing of dust dispersion in the dead-end mine working with brattice. Markers (porosity technique) have been used to create the complex geometrical form of computational domain. Results of numerical experiments which had been performed on the basis of the developed CFD model have been presented.

Purpose. This work involves the development of a numerical model for the calculation of areas of thermal damage to people in the event of solid propellant burning at the industrial site. Methodology. An equation expressing the law of energy conservation was used to solve the problem of determining the areas of thermal shock of people at the industrial site. A potential flow model was used to calculate the airflow velocity field in the presence of buildings at the industrial site where an emergency occurs. The numerical solution of the two-dimensional equation for the velocity potential is derived using the Liebmann method. This numerical model takes into account the uneven velocity field of the wind flow that is formed near industrial buildings. An implicit difference splitting scheme was used to numerically solve the energy equation. The physical splitting of a two-dimensional energy equation into a system of one-dimensional equations describing the temperature transfer in one coordinate direction has been carried out previously. At each splitting step, the unknown temperature value is determined by an explicit point-topoint computation scheme. Based on the numerical model built, the code using the FORTRAN algorithm language is created. Findings. Based on the developed numerical model, a computational experiment was conducted to evaluate the risk of thermal damage to people at the industrial site where solid propellants are produced. The dangerous areas for personnel are identified. Originality. An efficient numerical model has been developed to calculate the zones of thermal pollution in case of solid propellant burning. Practical value. Based on the developed mathematical model, a computer program was created, which allows performing serial calculations for determining the zones of thermal damage during emergencies at the chemically hazardous objects. The mathematical model developed can be used to design an emergency response plan for chemically hazardous objects.