CFD comparative analysis on the pollution characteristics of coal dust under turbulent airflow from coal cutting in the fully mechanized mining face

In order to investigate the effects of turbulent airflow from coal cutting (TACC) on the pollution characteristics of coal dust, the pollution behaviors of coal dust under the action of system ventilation airflow (SVA) only (Condition 1) and the addition of TACC disturbance (Condition 2) were respectively simulated and verified through a comparison with the field measurement data. The results show that the effects of TACC on the pollution characteristics of coal dust cannot be ignored on the operation site. TACC could not only enhance the turbulent intensity in the flow field, but also induce the positive deviation of airflow. The airflow with a velocity of about 1.0 similar to 1.75 m/s in the footway space moved from the region X=0.3 similar to 36.8 m, Y=4.1 similar to 4.5 m under Condition 1 to the region X=-5.1 similar to 26.5 m, Y=3.8 similar to 4.5 m under Condition 2. After the addition of TACC disturbance, the absolute value of positively-deviated airflow velocity component in the operational range of rear drum driver rose from 0 similar to 0.8 m/s to 0.2 similar to 1.8 m/s. Meanwhile, the flow field under Condition 2 could effectively cause lateral dispersion of coal dust to the footway space, which led to an increase in the lateral dispersion scale of coal dust. Under Condition 2, the region polluted by cutting-induced coal dust moved forward by 11.3 m along the negative direction of X-axis, and the peak coal dust concentration along the footway space was approximately doubled. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Automated summary

The study reveals that turbulent airflow from coal cutting (TACC) significantly influences the pollution characteristics of coal dust by enhancing turbulent intensity and inducing positive airflow deviation.