Abstract
The radiation plays an important role in the fire protection safety of equipments, especially for cable trays in switchgear rooms of a nuclear power plant. Therefore, many research works had been focused on the radiant heat emitted from a fire over the last decades. The radiant heat is essentially emitted from both the persistent and intermittent flames. However, no previous studies had investigated this heat contributed from the intermittent flame. Therefore, experimental and analytical works are proposed in this paper to investigate the effect of intermittent flame on the radiant heat. Based on the experimental measurements for a 30 cm pool fire, at least 36% of total radiant heat is emitted from the intermittent flame, demonstrating the significance of its contribution of the radiant heat. In addition, a new analytical radiant model is also proposed herein, which considers the intermittent flame effect, the flame oscillation characteristics and the smoke contribution. Compared with the experimental data for the pool fires with the diameters of 14-38 cm, the distributions of radiant heat fluxes predicted by the present analytical model show good agreement qualitatively and quantitatively. The relative errors between experiments and predictions are less than about 10%. © 2009 Elsevier B.V. All rights reserved.