Yang LZ, Zhou YP, Wang YF, Dai JK, Deng ZH, Zhou XD (2011) Autoignition of solid combustibles subjected to a uniform incident heat flux: The effect of distance from the radiation source. Combustion and Flame 158(5), 1015-1017. [In English]

Web link: http://dx.doi.org/10.1016/j.combustflame.2011.01.008

Keywords:

Radiant distance, Incident heat flux, Mass flux, Combustible pyrolysis, volatiles, flammability properties, charring materials, piloted ignition, wood, model, pyrolysis

Abstract: The ignitability of solid combustibles by a radiation source has been investigated experimentally as a function of distance between the solid and the source, for heating with a uniform incident heat flux. Unlike piloted ignition, the critical incident heat flux for autoignition increases with the increase of radiant distance, which is a result that has not been reported before. It is found that the generation rate of combustible pyrolysis volatiles is a necessary but not sufficient condition for autoignition. By two dimensionless parameters, it is clearly indicated that the occurrence of autoignition needs both sufficient gas-phase temperature and sufficient concentration of combustible pyrolysis volatiles simultaneously, especially for the larger radiant heating distance condition which is also closer to realistic fire conditions. (C) 2011 The Combustion Institute. Published by Elsevier Inc. All rights reserved.

 ,