Author(s)

Mingzhe Sun,Guoqing Zhu,Yunji Gao

Corresponding Author

Guoqing Zhu

ABSTRACT

FDS (Fire Dynamics Simulator) is used to simulate different HRRs fires in a horseshoe-shaped tunnel model with a real cross-sectional size of 1:1. Thermocouples are arranged in different cross sections of the tunnel to obtain entire temperature field. The ceiling maximum temperature prediction formula and the ceiling longitudinal temperature attenuation prediction formula are obtained which are consistent with the model of Albert and Gong. It is found that the dimensionless transverse temperature rise distribution under the semicircular ceiling conforms to Boltzmann curve, but the coefficients of the fitting formula are different in the turbulent flow zone near the fire source and the laminar flow zone away from the fire source. Transverse temperature distribution at the sidewall can be regarded as constant which equal to the temperature at the button of semicircular ceiling in most engineering applications. A prediction model is established to estimate the temperature of each position of tunnel wall. It provides a more accurate and detailed temperature field prediction method for tunnel fire prevention and structural damage research.

KEYWORDS

Tunnel fire; temperature field; transverse distribution; longitudinal attenuation