Enhanced temperature control performance in underground refuge chambers through optimization of air inlets layout

When the underground refuge chamber (URC) operates in the deep sections of mine, it frequently fails to effectively address the issue of indoor environment regulation. The ventilation system can effectively regulate the indoor air quality, serving as a cooling measure as well. An appropriately designed ventilation layout can enhance the uniformity of indoor temperature distribution, thereby improving temperature control performance. In this study, the accuracy of numerical simulation model was validated through experimental method. Numerical simulation was employed to analyze the impact of four factors on the temperature control performance of ventilation system: the distance between inlet and wall (DIW), the type of distance in adjacent inlets (TDIs), the angle of inlet in x-direction and y-direction. The results indicate that: (1) The ventilation layout in case 3 is the most effective. With an initial ambient temperature of
27℃, the effective temperature control duration is extended by 28 h compared to the typical ventilation scheme, reaching 79 h. Additionally, the temperature at 96 h was reduced by 0.4℃, and the waste heat emission efficiency improved by 9.67 %. (2) Given that the alteration of the ventilation layout has a minimal impact on the waste heat absorption efficiency, the variation in the heating rate is predominantly influenced by the waste heat emission efficiency. Consequently, waste heat emission efficiency is utilized to analyze the ranking of the four influencing factors of air inlets layout, which are ordered as follows: x-direction > DIW > TDIs > y-direction.