Experimental study of the effects of air volume ratios on the air curtain dust cleaning in fully mechanized working face

In order to fundamentally improve the dust cleaning efficiency of the fully mechanized woking face, the effects of air volume ratios (the ratio of forced airflow volume to exhaust airflow volume of the venti-lation system "gamma" and the ratio of radial airflow volume to axial airflow volume of the air curtain generator "phi") on the air curtain dust cleaning were studied by a combination of simulation experiment and field application. The experimental results showed that the migration process of the radial swirling air curtain was mainly affected by gamma; the smaller the gamma was, the more favorable it was for the trans-formation of radial airflow to axial airflow in a short distance. The states of airflow field in the operating region was affected by both gamma and phi; the smaller the gamma was and the larger the phi was, the more conducive it was for the formation of an integrated axial airflow field with uniform velocity distribution, the dust cleaning ability of the airflow could be improved continuously. The optimal air volume ratio was finally determined as gamma = 0.5 and phi = 9:1. By applying the optimal air volume ratio in 3(down)610 fully mecha-nized working face, the dust cleaning efficiency of main operating region could reach more than 94%, the air in the tunnel was clean, which could guarantee the occupational health and security operation of workers and meet the requirements of environmental sustainable development and cleaner production. (C) 2021 Elsevier Ltd. All rights reserved.