Dynamic assessment of occupational heat stress in deep mine roadways: A coupled heat-moisture model for predictive microenvironmental analysis.

Deep mining operations generate extreme thermal environments that impose serious occupational health risks on miners. To dynamically capture the spatiotemporal evolution of heat-moisture exposure, we developed a three-dimensional transient model incorporating a moving-mesh technique to simulate progressive excavation. The model, rigorously validated against field measurements (relative errors <2.0 %), demonstrates that excavation induces distinct airflow zones, with vortices near the working face forming critical hotspots of health risk. Within these zones, recirculation drives localized surges in temperature and absolute humidity, thereby intensifying heat stress in the primary work area. Moisture phase change was identified as the dominant contributor, accounting for approximately 80 % of the total heat load. This study establishes a robust predictive framework for occupational heat exposure and emphasizes that effective risk mitigation in deep mines must prioritize latent heat control and targeted cooling strategies in high-risk zones.