Investigation on temperature control based on cooled mine compressed air for mine refuge chamber with high-temperature surrounding rock

Abstract

Acceptable temperature is very important for mine refuge chamber (MRC) to ensure the safety of occupants. A novel temperature control scheme combining cold source storage with mine compressed air (MCA) was proposed for MRCs. An experiment was conducted to explore the characteristics of temperature controlling in a MRC via the MCA. Effects of several main factors such as initial surrounding rock temperature (ISRT), ventilation temperature (VT), ventilation rate (VR) and heat rate (HR) on the performance of temperature controlling in the MRC were numerically studied. Results show that: (1) In the MRC, the heat transfer process between the air and walls will reach a dynamic equilibrium within 0.5 h; (2) The ambient temperature in the MRC increases linearly with the square root of time from 1 h to 96 h, the gradient increases with VT and HR but decreases with ISRT and VR; (3) Ventilation with rate of 0.3 m3/min per capita and temperature of 20 °C can meet the temperature control requirements of a MRC located in the sandstone layer with the ISRT of 32.2 °C. An empirical formula for predicting ambient temperature and a ventilation parameter calculation method for meeting the temperature control goal of the MRC are obtained.