Fire Safety Science Digital Archive

It has been demonstrated by previous experiments within a cavity space having no bottom opening that the temperature rise of a plume at the height of the cavity opening is well scaled by a nondimensional temperature defined as ? = (?T/T?) Q*2/3 where Q* = Q/r?CPT? ?gDD2, and the temperature is successfully correlated as ? = a(H/D)?, where ?= -5/3, -1 and -1/3 for shallow, intermediate and deep cavities1),2),respectively. In this study, the smoke behavior in cavity spaces is further investigated by small scale experiments for a cavity space which has an opening at the bottom. It is shown that as the area of the bottom opening becomes larger, the fire plume becomes more stable, but the temperature is still well correlated in the same manner as for a cavity having no bottom opening. The effects of a bottom opening on the temperature and the pressure difference produced in the cavity are also analyzed.