Transient Characteristics of Unconfined Fire Plume-Driven Ceiling Jets. Annual Report 1986-1987

摘要

Measurements have been made of transient ceiling jet temperature and velocity profiles under an unconfined fiberboard ceiling for fire strength of 0.5 to 2.0 KW and for floor to ceiling heights of 0.5 and 1.0 m. The data indicate that the velocity profiles are independent of time. The temperature profiles show an increase of the maximum ceiling jet temperatures and a decrease of the distance of the maximum temperature from the ceiling with increasing time. The location of the point of maximum velocity and the point of maximum temperature become independent of the ratio of the radial position to ceiling height (r/H) at large values of r/H. The maximum velocities are less than those expected from isothermal wall jet theory.