Study on characteristics of multi-direction coupling flame spread and combustion after central ignition of inclined XPS sheets

doi:10.16265/j.cnki.issn1003-3033.2019.11.011

Abstract

Abstract: For the sake of studying development characteristics of thermoplastic sheets' flame spread after central ignition, a series of experiments were conducted on square XPS foam sheets at different inclination angles, and correlation between flame spread condition, velocity and the internal temperature was analyzed. The results show that the shrinkage after central ignition causes change of energy received in preheated zone, thus making upward flame spread more difficult along sheets with bigger inclination angle. In addition, when inclination angle is getting greater, velocities of upward flame spread increase, which is also greater than those of downward and horizontal flame spread. Besides, velocities of downward flame spread decrease firstly and then increase while horizontal flame spread velocities are less affected by inclination angle. It is also found that flame spread is sustainable if there is a violent temperature rise after heating. On the contrary, it is easy to extinguish if XPS foam shrinks significantly with a slow temperature rise.

Key words: extruded polystyrene (XPS) foam sheet, inclination angle, central ignition, internal temperature field, multi-direction coupling flame spread

CLC Number:

X932

DA Liangjun, XIE Qiyuan, LUO Shengfeng. Study on characteristics of multi-direction coupling flame spread and combustion after central ignition of inclined XPS sheets[J]. China Safety Science Journal, 2019, 29(11): 64-70.

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