An assessment of the dust suppression performance of a hybrid ventilation system during the tunnel excavation process: Numerical simulation

Abstract

The high concentration of dust particles produced during excavation processes in mine tunnels are a serious threat to workers’ health. Accordingly, in order to ensure safe production in mines, it is of vital importance to gaining an in-depth understanding of the dust pollution control rules in a tunnel. The appropriate use of far-pressure-near-absorption (FPNA) ventilation systems can contribute to achieving the suppression of dust in a working face and safeguarding workers’ health. In this study, through the use of computational fluid dynamics’ (CFD) techniques, numerical simulations were performed in a tunnel to assess the dust suppression performance of a hybrid ventilation system. In these simulations, the air exhaust quantity (Qc) and the height of the air pressure duct above the tunnel floor (Dy) were set at different values. The simulation results were validated using data from field measurements. If the pressure air quantity (Qy) remained unchanged the diffusion distance of highly concentrated dust decreased with an increasing Qc. From an economic perspective, 550 m3/min was determined to be the optimal value for Qc. When Qc was fixed at 550 m3/min but Dy was increased, the diffusion distance of highly concentrated dust first decreased and then increased. Therefore, an optimal dust suppression performance was achieved when Qc = 550m3/min and Dy = 2 m. The present study therefore provides a new scheme for improving the underground operating environment and achieving safer production.