Abstract
Japanese mining industry has experienced several major disasters caused by mine fires. One of the reasons for many fatalities in those fires is an unexpected change in airflow direction in the ventilation network which is produced by the fires. Therefore, the knowledge of the effect of mine fire on mine ventilation network is indispensable for the management of personnel escape, rescue and fire fighting activities. The simulation of mine fire is also necessary to perform effectively these activities and mine ventilation control under mine fire.
A mine fire influences airflow in a mine ventilation network mainly in two ways, that is ,"ventilation pressure created by a fire (natural draft effect)" and "throttling effect". Air temperature distributions in the network is required in order to estimate the strength of the two effects. The air temperature is changed by the mixing with the fire gas downwind of a fire. Therefore, the fire gas temperature in the network is indispensable to make reasonable mine fire simulation by a computer. However, there is not a simple and reasonable method to estimate the fire gas temperature suitable for mine fire simulation yet. This paper discusses the method to estimate the fire gas temperature based on the results obtained in the actual size mine fire experiments.
It is concluded that Eq(22) is suitable for the prediction of the fire gas temperature in a roadway. Here, the fire gas is defined as the ventilation air which passed the fire zone, a mixture of the air and produced gases.
