Numerical Simulation and Thermophysical Feature Analysis of Fire Propagation Law in Large Urban Rail Transit Buildings

As the development of urban rail transit (URT) picks up speed, more and more attention has been paid to the safety hazards that threaten URT operations. In URT buildings with different fire resistance ratings, the combustion performance and fire resistance limit of their components must meet relevant national standards. It is of certain practical significance to explore the fire propagation law in large modern URT buildings. Considering the peculiarity of URT building fire, this paper carries out numerical simulation and thermophysical feature analysis of fire propagation law. Firstly, the fire propagation features in underground station and section (USS) of URT system were described, and the corresponding control equations were established for mass, momentum, and energy. Then, the factors affecting the attenuation coefficient, including heat exchange coefficient, convection coefficient, and radiation coefficient, were analyzed, and a prediction model was established for temperature attenuation. Experiments were carried out to verify the scientific nature of our numerical simulation of fire propagation law in URT buildings, and obtain the thermophysical properties of fire propagation in URT buildings.