Experimental investigations of flame shape, temperature and component distribution in pool fire model of vaporizing liquid fuels

: Eisenreich, N.; Krause, H.H.; Weiser, V.

Abstract
Pool fires are qualified for studying the combustion processes of chemicals in laboratory scale and incinerators. Regarded ground areas have been 12.5, 25, 50 and 100 square centimetre. Fuels were 2- propanol, isooctane and toluene. The flames show constant burning rates (about 10 g/(square meter s)). At first burning rate dependson kind of fuel and increases with ground area. Ground areas greater than 50 square centimetre show turbulence phenomena like real big hazardous fires. The flickering results out of periodical up rising organized structures, which can be explained by a cyclic combustion modell. The organized structures rise up to an altitude of four times the equivalence diameter of the burning area.The flames radiate grey emission. Emission-coefficents depend on the radiating volumes and the affinity of soot formation. Average ranges are Epsilon equal 0.05- 0.5. Measured temperatures of radiation reach 1200- 1500degreeC. Average temperatures in the upper flame are much less c ause of fluctuations. At the same reason the diffusion flame shows an immense surplus of air with an amount of 20% of necessary air. The buoyancy controlled flame suck combustion gases to the inner part of the lower flame region by entrainment.