Numerical analysis of shearer motion impact on longwall ventilation performance

The ventilation airflow in the longwall section of underground coal mines is significantly affected by the motion of mine equipment, particularly shearer operation. To develop an effective and efficient longwall ventilation design, it is essential to examine the effects of equipment operations on the airflow, dust, and gas distribution patterns. This study aims to numerically investigate the distribution of airflow, methane, and moisture content in the longwall section of an underground coal mine. The longwall shearer is considered to have a translational speed of 0.5 m/s and a cutting drum rotational speed of 55 rpm, traveling from the maingate to the tailgate. The ventilation air is considered to enter the longwall section with a velocity of 2 m/s, a dry bulb temperature of 15°C, and 70% humidity. The numerical modelling is based on advanced hybrid dynamic and overset meshing techniques. The performance of the hybrid meshing approach is validated against available experimental data. The shearer operation proved to impact the gas flow distribution, especially near the cutting drum picks. The shearer motion, however, showed minimal impact on the moisture distribution along the longwall face. It is evident that as the air moisture content increases, the methane gas flow distribution varies along the longwall.