Dynamic model construction and particle size effects analysis of dust movement during coal-cutting operations at mining face

To thoroughly investigate the dynamic behavior of dust during coal-cutting operations at the mining face, this study develops a three-dimensional dust motion model based on the generation characteristics of shearer-induced dust. Using representative particle diameters, the model quantitatively analyzes dust movement across three spatial directions: perpendicular to the coal wall, along the airflow, and vertical. Results indicate that, under unconfined conditions, dust migration distances in the perpendicular and vertical directions are positively correlated with particle size, whereas an inverse relationship is observed in the airflow direction. By integrating these directional dynamics , six distinct dust motion patterns are identified, each exhibiting unique migration characteristics. In confined roadway environments, dust particles display synchronized motion durations in all three directions. Further analysis reveals that, during the settling process, migration distance along the airflow remains inversely proportional to particle size, whereas the relationship with migration distance in the perpendicular direction to the coal wall remains uncertain. Moreover, the motion of fine particles can be approximated as a superposition of uniform motions across the three directions. These findings offer a theoretical foundation for dust migration analysis in coal mines and provide critical insights for developing efficient dust control strategies in complex underground environments . • The dust generated by the shearer exhibits six distinct initial movement modes. • Particle size markedly affects the movement distance of dust in all directions. • The spatial dimensions of the roadway affect the dust settlement locations.