Abstract:
In order to further enhance the effectiveness of coal mine dust control and improve the air quality in fully mechanized caving faces, the 122109 fully mechanized caving face and its adjacent intake and return airways in a specific mine were selected as the research subjects. By integrating the actual data of the working face and airways in the mine, a physical model was constructed. Numerical simulation was then carried out using Fluent software to comprehensively explore the characteristics of dust migration and distribution, as well as the dust suppression effect by the double air curtain system. Additionally, Ansys Design Modeler was utilized for model building and local refinement. The simulation results revealed that in the airflow field of the fully mechanized caving face, low-velocity zones were present at the corners of the airway, while high-velocity regions and eddy currents emerged around obstacles; the characteristics of dust diffusion demonstrated that its distribution followed diverse patterns, influenced by factors such as the location of dust sources, air flow direction, and airway structure, in the transfer and coal-crushing areas, dust was concentrated near the inner side and close to the roof, while in the roof-caving area, dust settled towards the floor; eddy currents caused dust to accumulate on both the inner and outer sides of the airway, and the dust mass concentration in the upper corner increased with height, and the distribution at the air outlet was relatively uniform; the simulated wind speed in the return airway was approximately consistent with the measured value, validating the accuracy of the simulation results. Regarding dust control, it was discovered that the double air curtain configuration could significantly reduce dust mass concentration, the average dust mass concentration decreased from 441.35 mg/m
3 to 52.27 mg/m
3, and the average dust suppression efficiency increased by 64.31%; moreover, when variables such as wind speed and horizontal height were held constant, the “middle-closed double air curtain” layout exhibited a more pronounced dust suppression effect, the average dust mass concentration decreased from 589.26 mg/m
3 to 102.25 mg/m
3, with an average increase in dust suppression efficiency of 82.65%. In conclusion, the double air curtain dust suppression technology not only effectively reduced dust concentration but also provided a novel approach to reducing dust control costs and enhancing work efficiency.