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Title | A Review of Empirical Studies of Fireband Behaviour: Part A |
Publication Type | Report |
Year of Publication | 2011 |
Authors | Ellis, P |
Abstract | The vast majority of empirical research of firebrand behaviour during ‘flight’ has employed wood samples of regular shape and combusted while tethered in an airflow at a range of fixed velocities or at a relative airflow equivalent to their terminal velocity. Ideally, firebrand samples should be combusted at an air velocity equal to their terminal velocity, and untethered. Australia arguably experiences the worst cases of spotting in the world, and this has largely been attributed to the firebrand characteristics of eucalypt bark, which varies enormously in morphology. Models for firebrand behaviour developed using wood samples may at best be suitable for a limited number of bark morphologies, and then only if validated. One study has quantified the firebrand characteristics of messmate stringybark, which is notorious for intense short distance spotting, using small samples of up to 6 g burnt untethered and hence burning at their terminal velocity. A very limited study of shed bark cylinders of a ‘gum bark’ type has failed to demonstrate that this type could cause the cases of extreme distance spotting for which the type is notorious. Thus, there is a need to validate the existing work on messmate stringybark and extend it to include large samples, possibly by investigating another notorious stringybark, for example. In addition, there is a need to investigate possible agents for the long-distance spotting which is a feature of major fires, perhaps initially focussing on the types notorious for this type of spotting, but also investigating other firebrand material reported in the field. |