Heat Fluxes and Flame Lengths from Fires Under Ceilings

This study compiles the research that has been conducted on thermal conditions produced by fires under ceilings as well as additional new data for fires beneath ceilings in a corridor configuration. This includes fires in corridor/tunnel, unbounded ceiling, and corner configurations. For each configuration, the thermal conditions produced for both initiating fires impinging on the ceiling and burning ceiling fires are discussed. Thermal characterization includes flame length and heat flux at the ceiling, and correlations are proposed to predict these quantities for each configuration. Comparison of available data in the different configurations indicates that the highest heat flux conditions are produced with initiating fires impinging on a corridor ceiling.