Dynamic modeling of air temperature field and optimal cooling strategy design for advancing deep coal mining faces

To address the unclear spatiotemporal evolution mechanisms of airflow temperature fields and inefficient cooling design in heat hazard control for high-temperature coal mining faces, this study establishes a dynamic numerical model using a moving mesh method, validated with field data (relative error <2 %). Results reveal significant spatiotemporal heterogeneity: spatially, air temperature exhibits a "slow-sharp-slow" rise along airflow paths, with the working face section showing a steep gradient of 1.18 ℃/100 m; temporally, temperature decays exponentially initially, transitioning to a linear decline (0.19 ℃/100 m). Quantitative relationships between air temperature T_b, cooling load Q_c, and key parameters (cooling air temperature T_in, cooling air velocity v_in, and original rock temperature T₀) were established, demonstrating: (1) linear positive correlations between T_b and T_in or T₀, with an exponential negative correlation to v_in. (2) A critical regime transition was identified: cooling load negatively correlates with cooling air velocity below a critical cooling air temperature (linearly dependent on original rock temperature), reversing above this threshold. Field cooling implementation based on this quantitative model achieved an average temperature reduction of 9.5°C in mining faces, lowering thermal risks to 'heat-safe' level. Monthly production increased by 93000 tons per face, demonstrating significant occupational health and economic benefits.