Experimental investigation on the temperature control performance of compressed air coupled phase change plate system for underground refuge chamber

Controlling the temperature is a prerequisite for ensuring the safety of evacuees in underground refuge chamber. Previous studies have only studied the use of pressurized air or phase change for temperature control in underground refuge chambers. Moreover, there are limitations to the application of the two cooling methods. Therefore, in this paper, the temperature control method of compressed-air coupling phase change is studied, and its application in underground refuge chambers is expanded. This article experimentally studied the temperature control characteristics of the three temperature control methods, namely compressed air, phase transition, and compressed air coupling phase transition, and the effects of heating rate, compressed air volume and arrangement on the application of compressed air coupled phase change in underground refuge chambers were studied by control variable method. The results show that: (1) The temperature difference between the compressed air coupled phase transition and the compressed air is nearly 2.5 degrees C lower than that of the phase change plate, and the compressed air and temperature rise rate is similar to that of the compressed air coupled phase change, with a difference of only 0.02 degrees C/h, but the compressed air coupled phase change has a lower head and foot temperature difference. (2) When the compressed air volume is 360 m3/h, 3 /h, the cooling effect of the compressed air coupling phase change is better, but the indoor temperature distribution is uneven due to the large wind speed. (3) The smaller the number of people, the easier it is to control the internal temperature of the chamber, and the more difficult it is to control the larger the number of people. (4) Among the arrangement of two rows, three rows and four rows, the three-row arrangement is more suitable for the underground refuge chamber.