MODELING IGNITION AND BURNING RATE OF LARGE WOODY NATURAL FUELS

As part of the development of a model for predicting fuel loading redu ctions by and intensity histories of fires burning in large woody natu ral fuels, it was necessary to develop separate models for the process es of ignition and rate of burning of individual fuel elements. This p aper describes the derivation of predictive equations for ignition del ay time and burning rate (from diameter reduction rate) of large woody natural fuels in a fire environment. The method consists of deriving approximate functional forms using fuel component properties and a mea surable ''fire environment temperature'' and then fitting these forms to data taken in laboratory fires using a large propane burner. The eq uations describe the calibration data with precision adequate for the purpose for which they were designed.