BURNING BEHAVIOR OF LIVE AND DEAD PINUS HALEPENSIS NEEDLES USING SMALL SCALE CALORIMETRY EXPERIMENTS

摘要

Small scale laboratory experiments conducted in the Fire Propagation Apparatus calorimeter are presented tostudy the burning of Mediterranean pine needles (Pinus halepensis) under a wide range of conditions. Fresh live(45-55% Moisture Content (MC)), oven-dry live (1-3% MC), fresh dead (7-8% MC) and oven-dry dead (1-3%MC) samples are studied in a large set of more than 80 experiments with good repeatability. The use of a poroussample holder allows studying the ignition and burning of fuels for a range of heat and flow conditions thatmimic those encountered in real fires. The results show that the most flammable fuels are fresh dead, followed byoven-dry dead and oven-dry live, and the least flammable fuel is fresh live needle sample. The differencesobserved cannot be explained in terms of the MC solely as the fuel internal structure matters. Moreover, the lossof volatiles and other changes to the needles produced during the oven drying process lead to significantdifferences in the burning behaviour. The presence of an imposed flow of air inside the fuel bed has no effect onthe burning behaviour of fresh live samples but greatly affects dead and oven-dry needles. Overall, the resultsshow that fire physics and chemistry vary for each of the samples.