Abstract
Experiments were conducted with the aim of elucidating the effect of differences in the ratio Af/Ah=φ of the combustible surface area Af to the horizontal projection area Ah of a combustible on the reduction in heat release rate from supplying with water. Wood cribs (wood species: Japanese cedar) where the surface area ratio Af/Ah=φ can be easily created by changing the number of layers of stacking used for the combustibles. The main experimental parameters were "number of layers of wood cribs," "water delivered density," and "water supplying start time. In the experimental results, regardless of the number of layers of wood cribs, the heat release rate per unit area ΔQ'' that was reduced by supplying with water was proportional to the product of the water delivered density w and 1/φ (=Ah/Af). The constant of proportionality was virtually the same value (approximately 12.5 kJ/g in this experiment) for all water delivered densities and all numbers of layers of wood cribs.
