Numerical analysis of dust pollution evolution law caused by ascensional/descensional ventilation in fully mechanized coal mining face based on DPM-DEM model

To understand the problem of differences in the dust migration law of ascensional and descensional ventilation, this study numerically simulates the dust migration law under the condition of ascensional and descensional ventilation, and proposes corresponding automatic spray control schemes. The results show that under the influence of wind flow, the migration distance of dust under ascensional ventilation was longer than that under descensional ventilation at the same time, and the distance difference of dust migration between ascensional and descensional ventilation also increased with the evolution of time. Among them, the distance differences at 10 s, 25 s, 50 s and 75 s were 2 m, 7 m, 9 m and 14 m respectively. The lift of the ascensional wind hindered dust deposition, which caused the dust at 0–15 m on the downwind side of the shearer to seriously affect the breathing belt, with an average dust concentration of 1683.3 mg/m³ . The thrust of the descensional wind caused the roof near the moving support to seriously affect the breathing belt, with an average dust concentration of 1435.1 mg/m³ .