Investigation on cross-scale coupled airflow-dust evolution and highly efficient integrated “source-suction and airflow-barrier” control technology for low-height rapid tunneling faces

Aiming at the respirable dust hazards caused by restricted space, dense equipment layout, and high dust generation intensity during rapid excavation in low-seam coal mines with a seam height below 2.85 m, this study investigated the cross-scale coupled evolution mechanism of airflow and dust in low-height excavation roadways. An onboard integrated dust control and removal technology combining “source suction purification” and “airflow diffusion control” was proposed. A full-scale three-dimensional model of the 11,207 excavation face at Yuandatan Coal Mine was established using the CFD-DPM method and validated against underground measured airflow velocities, with errors controlled within 6%. The results show that, under the original forced ventilation condition, obvious recirculation zones and low-velocity stagnant zones formed within 0–40 m from the heading face due to jet reflection at the face and equipment obstruction, while the dust concentration in the breathing zone remained above 800 mg/m 3 . After introducing the onboard integrated system, the local airflow field was reconstructed. The optimization results indicate that, at an extraction airflow rate of 450 m 3 /min, the system achieves a balance between dust capture efficiency and ventilation stability, confining dust within 2 m of the heading face. Field tests show that the dust concentration near the heading face decreased from 976.78 to 58.05 mg/m 3 , with an average dust reduction efficiency of 94.1%. This study provides technical support for efficient dust control during rapid excavation in low-height roadways.