Experimental Investigation of Downward Flame Spread over RPU Samples

Abstract:

The combustion process of polymer is a complex coupling of energy feedback from flame to fuel surface with degradation of polymer. In this paper, a series of comparative laboratory-scale experiments were carried out to study the effect of sample width on downward flame spread over the rigid polyurethane (RPU) foam, a typical thermal insulation material. The variations of some important parameters such as flame height, pulsation frequency and flame spread rate were measured and analyzed. Results show that if the width fixed, the parameters mentioned above independent with time. If the width less than 25cm, the sample can not burn completely. With the expand of width, average flame height and flame spread rate present the same chang trend that increase first and then decrease and finally reach a steady state, flame pulsation frequency increases first and then decreases since sample width more than 20cm. The heat transfer from flame and pyrolysis zone to virgin region is proportional to the height of flame, and mainly dominated by radioactive regime.

• Periodical: Applied Mechanics and Materials (Volume 328)
• Pages: 921-925
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.328.921
• Online since: June 2013
• Authors: Yuan Ming Wang, Yong Ming Zhang, Heng Ze Zhao, Lan Ming Zhao
• Keywords: Downward Flame Spread, Flame Height, Flame Spread Rate, Pulsation Frequency, Rigid Polyurethane (RPU), Width Effects

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