Numerical Simulation of Multiphase Dust Transport Law and Scaled Model Testing of Spray Suppression Mechanism in Tunnel Blasting

Tunnel construction in western China is developing towards deeper burial, larger cross-sections, and longer distances. Dust and other pollutants generated during drill-and-blast construction endanger construction safety and workers’ health, making research on their migration and dust removal measures of great significance. This paper, based on the Zimuyan Tunnel, studies the dust migration characteristics and water mist dust removal schemes through three-dimensional numerical simulation (ICEM CFD modeling, Fluent analysis), 1:20 model tests, and on-site monitoring. The results show that eddies form at the working face in the later stage of ventilation, and dust exhibits vertical stratification due to differences in particle size; the nozzle angle and flow rate significantly affect the dust removal efficiency, and reasonable adjustment can improve the efficiency while reducing the impact on airflow; notably, both nozzle angle and flow rate affect in-tunnel airflow. The conclusion is that the distance of the air duct outlet should be adjusted to reduce the pressure difference to avoid eddies, and the nozzle angle and flow rate should be moderately adjusted to optimize the dust removal effect.