Abstract: To describe accurately the change process of airflow and gas in mine ventilation system during mine reverse ventilation period, the software TF1M3D was used to research the asynchronous reverse ventilation in multi-airshaft mine. The possible appeared three ventilator working conditions that shutdown, single operation, dual machine operation were defined and the according three codes were given respectively which were used to be the judgment of ventilator working condition. A numerical simulation test was made with the eighth of Hebi Colliery, the simulation results is consistent with the actual testing records of gas density. At the beginning of reverse ventilation, the ventilator stopped working, during a short pause, the mine ventilation relies on natural ventilation pressure, the velocity is low and the volume is small, the gas accumulation appeared in a short time. The airflow changes with the starting of reverse ventilation, TF1M3D gives out the change of ventilator operation point; at the same time, the gas flow changes with it, the peak overrun of gas in working face appears; with the reverse ventilation goes on, the gas concentration declines in stages. The asynchronous reverse ventilation simulation accurately describes the change of gas species in multi-airshaft mine during ventilation stopping period, and improves the calculation accuracy of emergency ventilation simulation.

Key words: disaster ventilation, mine reverse ventilation, fan working condition, concentration peak flow, 3D ventilation net simulation