A Numeric Simulation of Gas Migration in a Fully Mechanized Coal Caving Stope Based on Lattice Boltzmann Method

A numeric simulation of gas migration in a fully mechanized coal caving stope based on Lattice Boltzmann Method is put forward. A mining stope includes an inlet air tunnel, a return air tunnel, a working face and a goaf. There are two different states of air movement in a stope: turbulent flow in the inlet air tunnel, the return air tunnel, the working face (the three parts are simplified as working face) and seepage flow in the goaf, which fills with heterogeneous porous media, so gas movement in a mining stope is very complicated. To explore gas migration laws, two velocity-concentration double distribution models are constructed to simulate the flow field in the working face and the goaf respectively. They are computed in parallel. The flow field data in the working face and the goaf are exchanged through the block coupling algorithms, and the simulation of gas migration in the whole stope are realized. The simulation can get mass data about gas migration velocity, concentration and pressure and direct information about gas migration in a mining stope, which can provide basis for control gas migration.