Prediction of heatflow from surrounding rock into mine airways — a finite element study

CIM Bulletin, Vol. 87, No. 980, 1994

Kollu S. Rao, Department of Mining Engineering, Karnataka Regional Engineering College, Surathkal (O.K.), India B.S. Sastry and B. Misra, Department of Mining Engineering, Indian Institute of Technology, Kharagpur, India

This paper reports the results of a finite element study of the geothermal heatflow into dry mine airways. For isotropic and unsteady state conditions the heatflow into mine airways is studied for a range of surface heat transfer coefficients between rock and air, and age of the airway. Dimensionless temperature gradient values are presented in tables for different values ofBoit and Fourier numbers and the results are compared with Starfleld tables and Gibson algorithm. It is found that Starfleld tables have consistently over-predicted the G values with errors ranging from 2% to 10%. The differences between results obtained from the finite element study and the G values calculated from Gibson's approximation method are mapped. The small error values over a large range of Fourier and Biot numbers confirm the suitability of Gibson's algorithm to rapidly calculate G values for estimating the heat transfer from surrounding rock to mine air.

Mots Clés: Geothermal heatflow, Underground mining.