Distribution characteristics of an airflow–dust mixture and quantitative analysis of the dust absorption effect during tunnel sub-regional coal cutting

Optimizing the tunnel ventilation scheme is one of the main ways to achieve safe production in coal mines. Based on the actual production situation, computational fluid dynamics technology was used to study the distribution characteristics of an airflow–dust mixture for different air-absorption volumes (Qe) of the ventilation system during sub-regional coal cutting. According to the dust concentration values registered at different locations, the entropy weight method was applied to quantitatively analyze the dust absorption effect of the fan. The research results showed that: the dust distribution was jointly affected by the cutting unit and the completed cutting zone; moreover, the dust control effect was better in the middle cutting zones than in the others. Under the ventilation system, the overall distribution of dust in the tunnel could be roughly divided into three sections: the dust removal section (I), the dust blocking section (II), and the gentle section (III). The optimal Qe (575 m3/min) was determined based on the weight of the different zones. Finally, the entropy weight method was applied for determining the ideal mine ventilation system scheme and, hence, improve safety production in coal mines during sub-regional cutting dust production.