An empirical study of heat flow and temperature rise in bord-and-pillar workings in India

Results of investigations into climatic conditions in 19 bord-and-pillar semi-mechanised panels in the Raniganj coalfield in India are presented. Variables affecting transfer of heat and moisture and resulting rises in wet bulb and dry bulb temperatures in the panel have been critically investigated and statistical methods employed to identify the five most significant variables. These are: the temperature difference between virgin rock and air; air flow rate; average rate of advance of the panel; length of air flow path in the panel; and the wetness of roadways.

Regression equations have been worked out to give: the rise in dry bulb air temperature; rise in wet bulb temperature; gain in specific enthalpy; and gain in moisture content in the panel; in terms of the five variables mentioned earlier.