Influence of Air Volume and Temperature in the Air Inlet Tunnel on the Characteristics of Dust Movement

In order to clarify the movement characteristics of dust particles in the intake tunnel and improve the underground intake tunnel environment, the main intake tunnel of Wulihou Coal Mine was taken as the engineering background, the COMSOL simulation software was adopted to establish a model, the influence of air volume and temperature on dust movement characteristics was studied, and the critical air volume and particle size of dust at room temperature were determined. The results show that with the ventilation air volume being the same, when the dust reaches the exit of the tunnel, its falling height is positively correlated with the particle size. When the dust particle size is the same, the height of the dust falling is negatively correlated with the ventilation air volume. As the particle size of dust increases, the impact of changes in air volume on its movement decreases and the trajectory of dust movement gradually becomes consistent. The height of dust falling is negatively correlated with the air flow temperature. Therefore, when other factors remain unchanged, dust pollution in the tunnel is relatively severe during the day and the dust concentration in the tunnel is higher in summer. The critical air volume for dust emission in the intake tunnel of Wulihou Coal Mine is 75.84 m3/s, corresponding to a central wind speed of 5.29 m/s in the tunnel. The critical particle size for dust emission is 1.4 μm.