Multi-factor numerical simulation study on spray dust suppression device in coal mining process

In order to treat serious dust pollution problems in a fully mechanized mining face, computational fluid dynamics (CFD) was here used for numerical simulation. The atomization effects of the pressure swirling nozzles with three pore diameters of 1.6, 2.0, and 2.4 mm under the roadway airflow disturbance of 1.4 m/s and spray pressure of 1-8 MPa were simulated respectively. The results showed that the size of droplet had a power exponential relationship with the spray pressure. When the pressure exceeded 3 MPa, the change tended to be gentle; in presence of the spray pressure of 8 MPa, optimum atomization was achieved, over 90% of spray field droplets have particle sizes ranging from 20 to 100 mu m, and the distribution of the size of droplet was more uniform. When the spray pressure reached 8 MPa and the diameter of nozzle pore was 2.4 mm, more than 70% of the target area's spray field concentration was above 0.04 kg/m(2). After the field application by using a spray dust suppression device on the hydraulic support, the total dust and the respirable dust concentrations at the sampling points of the mining face significantly decreased, thus, the effect of dust control is obvious. (C) 2019 Elsevier Ltd. All rights reserved.