Underground Evironment Confort

Acta Geodyn. Geomater., Vol. 5, No. 4 (152), 341–349, 2008

MATHEMATICAL MODELLING OF THERMAL STATE IN UNDERGROUND MINING

.Vidal F. NAVARRO TORRES 1), C. Dinis DA GAMA 1)
and Raghu N. SINGH 2)Professor, Geotechnical Centre of Department of Mining Engineering, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal 2) Professor, Nottingham Centre for Geomechanics, Schoolof Civil Engineering, Faculty of Engineering, University Park, University of Nottingham, Nottingham NG7 2RD, UK and Professorial Fellow, University of Wollongong, Faculty of Engineering, NSW 2522,Australia Corresponding author‘s e-mail: vntorres@ist.utl.pt, dgama@ist.utl.pt, raghu.singh@nottingham.ac.uk
(Received August 2008, accepted October 2008)
1)

ABSTRACT The effect of temperature inunderground mines is related to the geothermal gradients of rocks overlying the mining excavation. This may exceed the standards of comfort for human beings to work in an underground environment thuscausing thermal discomforts and associated risk. In order to evaluate the influence of high ventilation temperatures on mine workers a mathematical model has been developed based upon the concept ofheat transfer from the rock mass to the air flow in the underground environment. This model has been validated in the Noves Corvo underground copper mine, Portugal.
KEYWORDS:

geothermal gradient,rock mass thermal properties, human comfort, underground mining environment

1.

INTRODUCTION

Thermal comfort is defined as the state of mind in which satisfaction is expressed with the thermalenvironment. The thermal human comfort is not exclusively a function of air temperature, but also of other parameters including mean radiant temperature, air velocity, humidity, activity level andclothing’s thermal resistance. Practical thermal human comfort evaluation is carried out by evaluating PMV (Predicted Mean Vote) and PPD (Predicted Percentage of Dissatisfaction) indices. Another...