Flame Heat Transfer Between Parallel Panels

Abstract

Flame heights and flame heat-flux distributions are measured for a wide range of fuels burning between two parallel panels. The flame heat flux levels are very sensitive to fuel sootiness. The heat flux distributions are obtained from the transient temperature rise of thermocouples peened into the steel parallel panel sidewalls. The measured flame heights imply an actual heat release rate per unit flame volume, 1110 = ? A q?? kW/m3, consistent with literature values. This heat release rate per unit volume is independent of fuel type and fire scale. The heat flux distributions are integrated to obtain the net total heat transfer ( ) 0 p Q q?? ?? ?? to the panels above an arbitrarily specified panel heat loss rate, 0 q?? ? . The integration is performed only over areas for which 0 0 ? ? ? ? q qf ?? ?? to obtain the net heat transfer, needed by fire growth models. The results are described by a simple theoretical model that assumes heat transfer occurs only by radiation. The model gives the net heat transfer p Q ?? as a function the fire heat release rate, A Q ?? , fuel smoke yield, s Y , gas equivalent smoke yield, g Y , parallel panel width, w and separation, d , as well as the flame volumetric heat release rate, A q ? ?? , and panel surface heat loss, 0 q?? ?