Study on the Temporal and Spatial Migration Patterns of Blast Smoke in the Mining Area and Optimization of Effective Range

To prevent toxic and harmful gas suffocation accidents in underground metal mine stopes, the Fluent numerical simulation method was employed to investigate the wind field distribution patterns and the diffusion laws of blasting fumes in stopes with and without middle–end roadways under varying effective ranges. The simulation accuracy was validated through laboratory experiments. The results demonstrate that over time, the CO concentration in the blasting area decreases, while in other regions of the stope, it initially increases before declining. The presence or absence of a middle roadway does not significantly alter the migration and diffusion behavior of blasting fumes in the stope. When the effective range is ER–1, the simulation error is only 8 s. As the effective range increases, the time required to reduce the CO concentration to 24 ppm on the respiratory plane, across the entire space, and at the monitoring point follows a linearly increasing trend. Meanwhile, the maximum wind speed at the working face exhibits a linearly decreasing trend, whereas the peak CO concentration shows a linearly increasing trend. Under the ER–1 effective range, the CO concentration can be reduced to a safe threshold more rapidly. The experimental and simulation results exhibit an error margin within 16.97%, confirming the accuracy of the numerical simulation.