Experimental and Numerical Simulation Analyses of Flame Spread Behaviour over Wood Treated with Flame Retardant in Ancient Buildings of Fuling Mausoleum, China

Abstract

AbstractTo protect ancient buildings from fire, prevent the occurrences of fire, and minimise the losses caused by fire to the maximum extent possible, this study combined experimental measurements and numerical simulations to analyse the flame spread behaviour over wood treated with flame retardants. First, some wood blocks were treated with a nitrogen and phosphorus (water-based) flame retardant, and then a smoke combustion experiment was performed to test the smoke density. Scanning electron microscopy was also employed to observe the flame retardant effect. Next, a fire dynamic simulation software was used to simulate and analyse the results of the flame spread behaviour over the yellow pine collected from the Long’en Hall of Fuling Mausoleum, that was treated with flame retardants. The results showed the variation trend of the fire site’s heat release rate (HRR) over time to be consistent with the movement of fire spread after its occurrence. Compared with pristine wood, the flame retardant-treated wood exhibited a HRR reduction of 53.1%. The addition of flame retardants also reduced the concentration of the released smoke and CO2 gas, decreased the temperature of the fire site, and enhanced visibility.