Abstract:
To effectively address the severe dust pollution issue in the fully-mechanized excavation face of coal mines, this study takes a fully-mechanized excavation face in Hulusu Coal Mine as the research background. A steady-state solver is adopted to conduct coupled simulations of the airflow field and dust field under different dust source locations and dust removal measures. Eventually, the steady-state distribution characteristics of key parameters such as dust trajectory, particle size, and dust concentration under different dust source locations are determined, and the influence laws of different dust removal measures on the ventilation and dust removal efficiency under various dust source positions are clarified. The results show that under forced ventilation, dust particles are entrained by the counterclockwise vortex near the heading face and diffuse toward the rear of the roadway. During the diffusion process, affected by both wind-driven dust removal and gravitational sedimentation, the dust mass flow rate gradually decreases, and the mass median diameter of dust continuously reduces. The average dust removal efficiency for different dust sources reaches 91.49%, with an average median diameter reduction rate of 17.42%. The dust source at the upper-left position achieves the optimal comprehensive dust removal effect, while the lower-left dust source performs the worst. Along the roadway direction, the dust concentration first rises rapidly to a maximum value, then drops sharply to a relatively low level, followed by a gradual slow decrease. The order of dust concentration for different dust sources is as follows: upper-left > middle > lower-left > upper-right > lower-right. Compared with the forced ventilation duct, the dust mass flow rates at the roadway outlet under measures including the wall-attached ventilation duct, forced ventilation duct combined with dust removal, and wall-attached ventilation duct combined with dust removal are all significantly reduced, with average reduction rates of 44.18%, 41.56%, and 75.32% respectively, and their comprehensive dust removal efficiencies reach 95.22%, 95.00%, and 97.89% respectively. It is recommended that the wall-attached ventilation duct combined with dust removal measure be prioritized for scheme design.