TF1M3D Simulation and Analysis of Gas Cloud Propagation in the Tunlan Mine “2.22” Gas Explosion Accident

To investigate the dispersion and complex propagation of toxic and hazardous hot gas clouds in mine ventilation networks following gas explosions, this study examines the Tunlan Mine “2.22” gas explosion accident. A simulation model of the Tunlan Mine was established, and gas explosion experiments were conducted to determine the initial concentration and temperature distribution of the gas cloud post-explosion. The TF1M3D simulation platform was utilized to model the post-explosion migration and spread of CO-deficient hot airflow under various ventilation conditions. The simulation revealed that when the Liangzhuang return air shaft fan failed for 30 min, CO-deficient hot airflow dispersed throughout the mine under the influence of other ventilation fans and residual explosion heat. After ventilation was restored, the hazardous airflow was completely expelled from the mine within 30 min. The simulation demonstrated that the hazardous airflow changed direction twice before and after the restoration of the Liangzhuang return air shaft fan, affecting working faces 12 403 and 12 405 twice and exacerbating the disaster’s impact and spread. The influence of self-rescuer time limits on personnel evacuation was analyzed in relation to the disaster airflow propagation process. The simulated disaster propagation patterns aligned with actual events. Drawing lessons from the accident, ventilation control strategies to facilitate personnel escape and mitigate disaster spread are proposed, providing reference for emergency ventilation control in mine gas explosions.