In addition, the maximum temperature in the three tunnel sections of interest is first recorded in the tunnel cross-section in the initial fire stage. As the wind speed increases, the normalized flame lengths R( f) in the two directions decrease, and the maximum temperature underneath the ceiling decreases. Moreover, the flame lengths underneath the timber-lining ceiling in the x-direction are longer than those in the y-direction. Moreover, the average flame-spread rate increases along the vertical flame-spreading direction and decreases when the flame reaches the timber-lining corners. It was found that cross-section flame spreading follows the three-stage sidewall-ceiling-sidewall pattern. In this study, experiments and numerical simulations were carried out using a fire dynamics simulator to investigate the flame-spread rate, flame characteristics, smoke movement, and spread process of timber-lining fires under different wind speeds of 0, 0.25, 0.5, and 0.75 m/s. These linings are essential to prevent broken rock from falling during the occurrence of exogenous fires.

Timber linings are applied as primary supports in the tunnel fault and fracture zones of mines.

Pyrosim multiple grid sizes