Mixing ventilation strategy for an underground refuge during mine emergency

  • Shu Wang, Longzhe Jin, Shengnan Ou, Zhiling Huang


Mechanical mixing ventilation (MV) systems have been commonly used in permanent refuge chambers (PRCs) to maintain sustainable environment for trapped miners during emergencies underground. For guiding the design of MV systems, in this study, 24 layouts with different combinations of the ventilation rate and number of diffusers were analyzed through simulations. The heat/carbon dioxide removal efficiencies, velocity non-uniform coefficient, local draft sensation, and thermal discomfort were calculated and discussed. Considering uncertain adverse circumstance during rescue, an optimal scheme with nine diffusers was proposed for a prototype. It is suggested the fresh air should be supplied at a minimum rate of 0.1 m3/min per person, which can fulfill the basic living demands at the cost of thermal neutrality. A full-scale on-site experiment, in which critical environmental parameters and sick building syndrome (SBS) symptoms were recorded, was also performed to verify the rationality of the proposed ventilation scheme.