Heat dissipation in high-temperature mine roadways: Critical controlling factors under seasonal airflow

• The heat transfer model under seasonal airflow temperature was established. • Roadway surrounding rock shows periodic heat storage/release under seasonal airflow. • The sensitivity order of influencing factors in the first 5 years changes over time. • Rock thermal conductivity is the most critical factor in the long-term stage. The exploitation of deep coal resources is inevitably accompanied by high-temperature thermal hazards, with surrounding rock heat dissipation as the primary heat source. To reveal the influence weights of various factors on roadway surrounding rock heat dissipation, a transient heat transfer model considering the seasonal airflow temperature boundary was established, and critical factors were identified via an orthogonal test. The results show that: (i) Roadway surrounding rock exhibits periodic heat storage and release characteristics under seasonal variations in airflow temperature. (ii) The sensitivity ranking of influencing factors changes within the first 5 years of heat exchange; overall, rock thermal conductivity, roadway radius, average airflow temperature, and original rock temperature are the primary factors, while rock specific heat capacity, rock density, airflow velocity, and airflow temperature fluctuation amplitude are secondary factors. (iii) Reducing rock thermal conductivity is the most effective measure, when it decreases from 4.8 W/(m·℃) to 0.8 W/(m·℃), the heat exchange intensity reduces by 77.4% (from 6.2 GJ/(m·a) to 1.4 GJ/(m·a)). (iv) Comprehensive measures such as optimizing roadway cross-sectional design, improving ventilation system planning, and prioritizing construction in low original rock temperature regions are also effective. This research provides theoretical guidance for the scientific prevention and control of mine thermal hazards.