Influence of ventilation velocity on coal dust diffusion based on CFD-DPM method
The ventilation of pressure cylinders directly affects the diffusion of the dust particles,which reduce the visibility of road-header drivers,and also tend to slowdown operating efficiency.Taking the 2601 mechanized working face of a coal mine in Shanxi as an example,CFD-DPM method was adopted to examine the airflow flow and dust diffusion behaviors in roadway under various ventilation velocities.The simulation results show that airflow field could be divided into airflow fast and chaotic disordered area,recirculation area with dust backflow,and stable area from the heading face to the exit of the roadway.The airflow was observed to carry the dust particles along the roadway wall away from the pressure cylinders from the disordered areas into the recirculation areas due to the blocks caused by the road-headers.The dust migration slowed down in the areas behind the road-headers due to the sudden decreases in the airflow velocities.Then,large amount of dust particles were carried by airflow into the stable areas.The remaining dust was carried to the exits of the pressure cylinders as a result of the dust backflow.As a result,areas of approximately 5 m behind of the road-headers,as well as the areas near the pressure cylinders,had high dust concentrations.The dust particles were attracted to the exits of the pressure cylinders due to the strong entrainment effect,and its concentration increased with increasing of the ventilation velocities.However,this only occurred when ventilation velocities exceeded 17 m/s.
国家科技期刊平台
NSTL
万方数据
维普
