Occurrence and development criteria of coal and gas outbursts based on energy conversion

Abstract

Coal and gas outbursts are sudden disasters in coal mines, they are major dynamic hazard during coal mining and have to be controlled for mining safety. To further understand the outburst process of coal and gas outbursts, an energy conversion model of coal and gas outbursts are established from the perspective of outburst energy conversion, and the criteria of outburst occurrence and development are determined. The energy conversion relationship and criteria of outburst occurrence and development are analyzed by physical simulation experiments. The results show that the critical threshold of the two groups of experiments is 2600 J. When the outburst potential energy exceeds the critical threshold, the outburst phenomenon occurs. Some of the outburst potential energy is converted into effective outburst potential energy to participate in the outburst work with the outburst process. The effective potential energy conversion rate of the two groups is 52 %-55 %. In the outburst of each experiment with outburst phenomenon, the development criterion values are 1.16–1.20 for experimental group 1, and the values are 3.06–3.75 for experimental group 2. The result indicates that the necessary condition for outburst development is that the outburst effective potential energy is sufficient to overcome the outburst energy consumption. This study will be of great scientific significance for exploring the outburst mechanism.