Upward Flame Spread Mechanism along a Napped Fabric

摘要

A napped fabric is known to catch a fire easily, and the flame spreads along the napped surface very fast, i.e. a flash flame spread occurs. It may cause a parson wearing the napped fabric to be burned alive. To avoid such a fire accident, flame spread phenomena along a napped fabric must be clarified and the flash flame spread along its surface should be suppressed. For this purpose, the flash flame spread along a napped fabric has been investigated. The absorbent cotton which is napped mechanically was used as a sample of a napped fabric. Dependence of the flash flame spread rate on depth or density of a napped layer was studied experimentally. It was ascertained that the flame spread rate depended on both the depth and the density of the napped layer. Considering the experimentally obtained dependency, a heat transfer model of the flame spread along a napped layer was developed. From the model taking the experimental results into account, it was revealed that the flame spread rate was governed strongly by a convective heat transfer in the case of upward flame spread along a napped fabric.