Numerical simulation of migration and diffusion of exogenous gas in mine roadways

A mathematical model was established based on numerical simulation of one-dimensional finite element method. The computer simulation program was designed. Analysis of the propagation progress of exogenous gas in ventilating roadways was done by computer simulation system. The calculation shows that if the concentration gradient of exogenous gas is too huge, the convection item becomes too strong, and the discretization time and the scale of space subdivision are too large, which leads to cloud distortion in the gas dispersion of front airflow. The distortion phenomenon tends to disappear after improving the algorithm, namely adopting a format of upwind finite element, adjusting upwind factor by the computer program automatically, and decreasing the subdivision scale of time-space discretization. After these treatments, a good convergence effect is obtained when the airflow velocity is 2.252 m/s and division scale less than 2.5 m. We bring the algorithm of single branch into network solver of mine ventilation, and the simulation expression of the spreading and diffusion of exogenous gas in a network is achieved.