The paper presents the results of the mathematical modeling of the conditions for ventilating extended blind dead end stope chamber-like mine workings of large cross-section, which are formed by expanding the preparatory rifled mine working when loading and hauling machines with an internal combustion engine are operating in them. The experience of using CFD-modeling in solving problems of ventilation of such mine workings is analyzed. Numerical dependences of the change in the average concentration of exhaust gases at the workplace of the load-haul-dump machine operator on the operating time of equipment with an internal combustion engine in the stope area of the chamber were obtained. These dependencies allowed to determine the coefficient of efficiency of ventilation of dead-end stope chamber-like mine workings of large cross-section when operating equipment with an internal combustion engine in them.
It was found that the ventilation efficiency coefficient can be taken equal to one both in the case of an increase in the concentration, and in the case of its decrease. The conclusion is made about the same regularities in the processes of accumulation and removal of harmful impurities in the dead-end mine working.
Using a parameterized model, expressions were obtained for determining maximum operating time of the machine with an internal combustion engine for unloading ore from the stope area without exceeding maximum permissible concentration of the exhaust gases. An expression is also presented for calculating the minimum ventilation time of the chamber after the vehicle leaves and before its re-entry into the chamber. Made conclusions and obtained dependencies will allow to ensure safe working conditions for the miners in the extended dead-end stope chamber-like mine workings of large cross-section.
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