Numerical investigation of dust dispersion in a coal roadway with hybrid ventilation system

Coal dust explosion is one of the most serious hazards in underground coal mines. To prevent or alleviate this hazard effectively, it is necessary to investigate dust dispersion in underground coal mines. In this study, dust movements in a simplified coal roadway with hybrid ventilation system were investigated based on the Euler-Euler and the Euler-Lagrange methods. First, coupling velocity fields under different conditions were obtained via the Euler-Euler method. Second, dynamic behaviours of certain dust particles in the coupling flow were evaluated via the Euler-Lagrange method. Meanwhile, particle collisions were considered with sample particles, and the hard-sphere model were applied accompanying by the direct simulation Monte Carlo method. Third, the bulk movements of dust particles with different sizes were explored under multiple conditions. Dynamic characteristics of dust dispersion were identified, including dust sedimentation, dust circumfluence and dust distribution, In particular, dust dispersion was examined for suspended particulate matter. It was found that dust particles of varying size exhibit different tendencies during dust dispersion. Furthermore, selected simulation results showed reasonable agreements with relatively few results from the previous experiments and the relevant survey. The present results on dust dispersion can be used to further understand dust movements in coal roadways. (C) 2017 Elsevier B.V. All rights reserved.