Calculating Entrainment and Flame Height in Fire Plumes of Axisymmetric and Infinite Line Geometries

Abstract

New correlations for flame height and far and near field entrainment are developed from existing data and simple point source theory based on conservation of mass, momentum and energy in the fire plume. These correlations provide prediction of entrainment and flame height for linear sources and for axisymmetric sources. Source geometry and combustion zone radiation heat transfer are incorporated into near field entrainment and flame height correlations. Near field entrainment correlations are compared with other existing correlations and show some differences. Far and near field entrainment correlations for the axisymmetric source are graphed together to show how to calculate entrainment throughout the entire plume. A comparison of entrainment from axisymmetric and infinite line sources of equivalent strength and fuel bed area has also been included.