Molecular dynamic simulations of the thermal degradation of polyethylene were used to identify factors which might be effective in reducing polymer flammability by promoting the formation of a residual char. Computer movies of the calculated trajectories indicate that cross-linked polymers, such as those obtained from exposure of polyethylene to ionizing radiation, will undergo further cross-li...

Extinction limits and flame bifurcation of lean premixed dimethyl ether-air flames are investigated numerically using the counterflow flame with a reduced chemistry. Emphasis is paid to the combined effect of radiation and flame stretch on the extinction and flammability limits. A method based on the reaction front is presented to predict the Markstein length. The predicted positive Markstein l...

A large pilot plant was constructed to study the upper flammability limit of ethene-air-nitrogen mixtures under conditions of flow. The gas mixtures flowed through an explosion tube with a length of 3.0 m and a diameter of 21 ram. An electrically heated wire was used as ignition source. Experiments were performed at pressures of 5 and 10 bar, with gas temperatures between 25 and 300 °C and with...

During periods with epidemic mountain pine beetle (Dendroctonus ponderosae Hopkins) populations in lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) forests, large amounts of tree foliage are thought to undergo changes in moisture content and chemistry brought about by tree decline and death. However, many of the presumed changes have yet to be quantified. In this study, we...

Fire is nearly ubiquitous in the terrestrial biosphere, with profound effects on earth surface carbon storage, climate, and forest functions. Fuel quality is an important parameter determining forest fire behavior, which differs among both tree species and organs. Fuel quality is not static: when dead plant material decomposes, its structural, chemical, and water dynamic properties change, with...

Diversity effects on many aspects of ecosystem function have been well documented. However, fire is an exception: fire experiments have mainly included single species, bulk litter, or vegetation, and, as such, the role of diversity as a determinant of flammability, a crucial aspect of ecosystem function, is poorly understood. This study is the first to experimentally test whether flammability c...

1CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia 2School of Resources, Environment and Society, The Australian National University, Acton, ACT 0200, Australia 3Email: [email protected] 4Department of Mathematics and Statistics, University College, University of NSW, Campbell, ACT 2602, Australia 5Bushfire Cooperative Research Centre, Australia 6Snowy Mountains Region Fire ...

As a fundamental study relevant to micro-combustor application, the effects of mixture dilution on the lean extinction characteristics is studied for a stagnation-point flow system with a methane/air mixture over a platinum surface. For steady conditions, the level of flammability extension by surface reaction depends strongly on the mixture dilution, such that the benefit of catalyst-assisted ...

Background Mitigation of wildfires at the wildland–urban interface (WUI) will be enhanced by understanding flammability plants growing in this zone.Aims We aimed to: (1) compare shoot among wildland native, and both urban native exotic ornamental plants; (2) quantify relationships between traits flammability; (3) establish scores to distinguish low- from high-flammability species.Methods Flamma...

Studies examining plant flammability descriptors as fire-adaptive traits (e.g. Schwilk, 2003; Scarff & Westoby, 2006; Cowan & Ackerly, 2010; Saura-Mas et al., 2010; Pausas et al., 2012) are normally formulated within the framework of inclusive fitness theory. In such a framework, flammability-enhancing traits are considered to favour individuals if the elevated flammability confers fitness bene...