Determination of the optimal axial-to-radial flow ratio of the wall-mounted swirling ventilation in fully mechanized excavation face

The dust and gas control effect of the wall-mounted swirling ventilation method is closely related to the axial-to-radial flow ratio of the forced air. In order to determine the optimal axial-to-radial flow ratio, a scaled physical model of the wall-mounted swirling ventilation was developed based on the prototype of the fully mechanized excavation face, C103, in Nahe Coal Mine, Baise City Mining Bureau, Guangxi. The airflow field, dust diffusion pattern, and gas concentration distribution under different axial-to-radial flow ratios were investigated using numerical simulation based on k-E turbulence model, discrete phase model (DPM), and component transport model. The results showed that the axial-to-radial flow ratio of 2:8 was reasonable for the fully mechanized excavation face in this study. Under this axial-to-radial flow ratio, the gas concentration of the working face can be controlled within the safety limit, while a desirable dust-control effect can be achieved. (C) 2019 Elsevier B.V. All rights reserved.