SLOPE AND FUEL LOAD EFFECTS ON FIRE BEHAVIOR - LABORATORY EXPERIMENTSIN PINE NEEDLES FUEL BEDS

Laboratory fire experiments were conducted in both Pinus pinaster and Pinus halepensis litters in order to investigate the effect of slope o n fire behaviour for different levels of fuel load. Simulated slopes r anged between -30 degrees and +30 degrees. The results are reported in terms of rate of spread and rate of mass loss when observed fire was quasi-steady. Upslope fires were observed, on the present devices, to be unsteady, and their flame to be three-dimensionnal, when slope and fuel load exceeded certain limits. The heat transfers involved in the explanation of the observed behaviours are discussed, especially on th e base of the quite different results obtained in the two tested fuel. beds.