Experimental study on dynamic evolutions of airflow in the ventilation network under the effect of mine gas outburst disasters

Coal and gas outbursts represent a complex and dynamic phenomenon. To further clarify dynamic evolutions of airflow under the effect of gas outburst disasters, an experimental device for simulating gas-induced airflow disturbance under the circumstances of outburst disasters was constructed. With the aid of this device, relevant parameters such as outburst intensity, airflow composition, and wind speed were analyzed based on experimental results. Here are the research findings: (1) Gas acts on the entire process of coal and gas outburst disasters. It plays a dominant role in the outburst development and propagation stages, manifested as the action of gas natural wind pressure. (2) The outburst roadway pressure within the mine ventilation network undergoes a cyclic attenuation process. The first moment when the pressure drops to the atmospheric pressure can be regarded as a criterion for judging when the outburst gas source power no longer works and the gas natural wind pressure starts to act. (3) Outburst gas and ventilation power jointly act on the mine ventilation network, resulting in airflow disturbance and backflow. This reveals that gas natural wind pressure and ventilation power coexist and interact with each other during the disaster.