Numerical investigation of coal dust migration in sealed tunneling environments: A CFD-based study

Effective dust control is crucial for improving air quality and worker safety in underground mining operations, particularly in sealed excavation faces where traditional ventilation methods are insufficient. Understanding the behavior of coal dust in such environments is essential for developing targeted control strategies. Transitioning from ventilated to sealed tunneling dramatically changes dust dispersion dynamics. High-concentration dust (5,000 mg/m³) primarily diffuses along the roof toward the sidewalls and distal regions of the tunnel, rather than being dominated by airflow velocity and volume. Initial gas composition and dust particle size significantly impact dust concentration, with changes ranging from - 99% to + 1,216% and - 72% to + 169%, respectively. In contrast, methane emissions and temperature variations have limited effects on dust concentration. Based on these insights, we propose specific dust suppression strategies for sealed tunneling environments, offering practical solutions for dust control in similar mining scenarios.