Study on airflow-gas migration characteristics in blanking chamber based on CFD

ZHANG Hongjie; HAN Bo

doi:10.11799/ce202602019

Abstract：To meet underground production demands,blanking shafts and blanking chambers have become essential facilities for mine materials supply.However,the construction of blanking shafts and the material blanking process significantly affects the airflow-gas transport within the chamber,an issue particularly prominent in high-gas mines.To clarify the impact of blanking shaft construction and the blanking process on the airflow-gas distribution characteristics inside the chamber,a physical model of coupled airflow-gas diffusion was established by introducing the gas component through a component transport model.We systematically investigated the influence of material blanking on the airflow-gas distribution patterns within the blanking chamber and shaft.The results show that without a blanking shaft,there is no significant airflow movement inside the chamber,leading to local gas accumulation.After the blanking shaft is operational,airflow enters the chamber along the shaft under pressure difference,forming vortices that effectively reduce the overall gas concentration in the chamber.However,gas accumulation occurs at the upper corner of the chamber,with a volume fraction over 0.09%.As the gas concentration in the system airflow increases,the gas dispersal efficiency driven by pressure difference gradually diminishes.Compared to pressure difference,increasing the system airflow velocity can more effectively reduce the gas concentration at the chamber's upper corner,with higher velocities yielding more significant dispersal effects.Additionally,forced ventilation using auxiliary fans leverages the Coanda effect to deliberately increase airflow in the upper corner,optimizing internal air distribution and dispersing accumulated methane.