Combustion and fire safety of energy conservation materials in building vertical channel: Effects of structure factor and coverage rate

摘要

Experimental study on combustion and firesafety of energy conservation materials (extruded polystyrene, i.e., XPS) in vertical channel with front openings of building fa?ade is conducted, and effects of channel structure factor (α) and curtain wall coverage rate (β) are revealed. The XPS ?ame in the vertical channel is turbulent. There is a correlation between the ?ame height and pyrolysis length: xf = mxn p, where m and n vary with the change in structure factor and coverage rate. Upward ?ame spread rate decreases first and then increases as β rises. When 0 ≤ β 0.2, the restraining effect of vertical channel on air entrainment dominates, while for 0.2 ≤ β ≤ 0.8, the heat feedback from curtain wall dominates. When β = 0, the in?uence of α on ?ame spread rate is not signifcant. The ?ame spread rate increases with increasing α when 0.2 ≤ β ≤ 0.8. A model is established to predict the ?ame spread rate under different coverage rates and structure factors. Compared with experimental results, the prediction error is smaller than 10%. Larger values of ?ame height and ?ame spread rate correspond to higher firehazard. This work is benefcial for firesafety assessment of building thermal insulation materials and optimal design of energysaving curtain wall.