Analysis of the impact of local resistance of mine workings on the total mine air-flow resistance

This paper aims to provide a quantitative assessment of the effect of local aerodynamic resistance on total mine airflow resistance with account for the friction resistance. The research includes laboratory tests, computer simulations in the Ansys CFD software as well as analytical inferences. The performed studies specified the magnitudes of local resistances at the turnings of mine workings. It has been established that the value of local resistance in all the sections can exceed 10% of the total mine aerodynamic friction resistance. This depends on the geometric parameters of the mine workings, which may result in a significant increase in the ratio of the local resistance value to the aerodynamic friction resistance value. The correlation of the two coefficients, i.e. the friction coefficient and the coefficient of local resistances, are proved to have a significant impact. The sharper the turns of the mine workings are, the greater the ratio of the local resistance to the aerodynamic friction resistance value is. Therefore, it is necessary to take this type of resistance into account when designing mine ventilation systems.