. Introduction
Flashover is a thermal instability phenomenon to characterize
the rapid transition from the growth period to the fully developed
fire [1]. Flashover promotes the rapid flame spreading from a relatively
small local area over all the combustible surfaces. After flashover,
the whole space is engulfed in flames with high temperature
and rapid spreading of toxic smoke, which seriously endangers the
lives and property in constructions [2].
There have been many experimental studies of flashover in
compartments. Waterman [3] conducted series of full scale flashover
experiments in a 3.64 m 3.64 m 2.43 m compartment
with the ignition of paper on the floor as the sign of flashover.
Quintiere and McCaffrey [4] assessed the critical pyrolysis rate of
cellular plastic materials in furniture on the occurrence of flashover
in a room with different door size. Chow et al. [5] conducted ignition
tests of PVC and PC plastics in a room calorimeter similar to
ISO9705 test chamber, and found the critical radiant heat flux
15 kW/m2 at the floor level and the critical upper hot smoke layer
temperature 650 C. Luo [6] suggested that the CFD modeling
should incorporate the ventilation conditions by the comparison
of a full-scale multi-room apartment flashover experiment and
numerical simulation results. Klopovic and Turan [7] found that
radiation is not so significant on the flashover occurrence and
direct flame contact can ignite secondary fire based on a series of
full scale fire experiment.
Supported by experimental observations and statistical analysis,
the radiant heat flux to the floor of about 20 kW/m2 was concluded
as the critical criterion for the occurrence of flashover