Fire effects on the physical environment in the WUI using FIRETEC

Abstract

A navegação consulta e descarregamento dos títulos inseridos nas Bibliotecas Digitais UC Digitalis, UC Pombalina e UC Impactum, pressupõem a aceitação plena e sem reservas dos Termos e Condições de Uso destas Bibliotecas Digitais, disponíveis em https://digitalis.uc.pt/pt-pt/termos.Conforme exposto nos referidos Termos e Condições de Uso, o descarregamento de títulos de acesso restrito requer uma licença válida de autorização devendo o utilizador aceder ao(s) documento(s) a partir de um endereço de IP da instituição detentora da supramencionada licença.Ao utilizador é apenas permitido o descarregamento para uso pessoal, pelo que o emprego do(s) título(s) descarregado(s) para outro fim, designadamente comercial, carece de autorização do respetivo autor ou editor da obra. Na medida em que todas as obras da UC Digitalis se encontram protegidas pelo Código do Direito de Autor e Direitos Conexos e demais legislação aplicável, toda a cópia, parcial ou total, deste documento, nos casos em que é legalmente admitida, deverá conter ou fazer-se acompanhar por este aviso.Fire effects on the physical environment in the WUI using FIRETEC Autor(es):Pimont, F.; Dupuy, J-L.; Linn, R. R. AbstractIn France, the clearing distance between buildings and forest edge is 50 m, to allow fire fighters to protect those buildings. Current building recommendations in the wildland-urban interface derive from fire-safety tests on building materials using heat exposures (duration and magnitude) that are expected to be different from those produced by wildfires. Beyond a few experimental data released after the International Crown Fire Modelling Experiment, there is a lack of characterisation of the physical environment of a building or human target within a cleared area, that receives hot gases and radiant fluxes from a crown fire. In the present study, we evaluate FIRETEC's ability to simulate heat fluxes based on some available experimental data and subsequently use it to characterize the radiant fluxes, gas temperatures and velocities around a human or building target.Simulations have been performed in a mature Aleppo pine forest within a 600 by 400 m domain. The conditions of the fire spread were severe (30°C, wind up to 50 km/h, slope until 30%). Radiant fluxes and gas temperatures were computed for several distances between the forest tailing edge and a target that represents either a building or a fire fighter. Peak radiant heat flux magnitudes decreased by about 80% when the target was at 50 m compared to a target at 10 m. This is between 90 and 95% reduction o0f radiant flux reduction observed at 50 m compared to the forest edge. For the purpose of comparison with reference acceptable thresholds for both materials and fire fighters, the peak values of the average over one minute of the instantaneous radiant fluxes and gas temperatures were computed. These values support the notion that a clearing distance of 50 m is appropriate in the tested conditions for both thermal radiation and gas temperature, even if radiant fluxes remain high ...

Modeling fuels and fire effects in 3D: Model description and applications

“…The use of physics-based fire models is a rapidly growing field, and has promise for providing insights useful to many contemporary fire and fuel questions due to the greater detail with which fuel information can be used and the advantages of mechanistic process modeling in physics-based models. Previous simulation efforts have illustrated that these models produce outcomes that compare favorably with observed data (Linn and Cunninham, 2005;Mell et al, 2007;Pimont et al, 2009;Linn et al, 2012;Pimont et al, 2014;Dupuy et al, 2014;Mueller et al, 2014;Hoffman et al, 2015b).…”

Effets de la récurrence des incendies sur le comportement du feu dans des suberaies (Quercus suber L.) et maquis méditerranéens sur les cinquante dernières années

“…The velocity of the wind was constant in all simulations (10 m/s at a height of 40 m, as prescribed by the Fire Paradox project), and the slope was kept constant. We note that many validations were conducted with Firetec in Mediterranean shrublands [16] with abiotic and biotic parameters: slope [17], water content and vegetation density [18], in canopies [19][20][21], interactions between plumes of fireback [16], radiative fluxes [20], and gas speed/temperature in the fire plume [22].…”

“…Un grand nombre de validations ont é té conduites avec le modè le. Celles-ci concernent les calculs d'é coulements [48], le comportement du feu en pré sence de topographie [17], la propagation du feu dans des garrigues mé diterrané ennes [16], la sensibilité de la vitesse de propagation à la densité et la teneur en eau du combustible dans des maquis espagnols [18], la propagation du feu dans des canopé es [19][20][21], l'interaction entre panaches dans le contexte du contrefeu [16], les pré dictions de flux radiatifs à l'interface habitat/forêt [20], ainsi que la vitesse et la tempé rature des gaz dans le panache [22].…”

A Specific Large-Scale Pressure Gradient Forcing for Computation of Realistic 3D Wind Fields Over a Canopy at Stand Scale

“…conditions on a more refined domain with substantial heterogeneous vegetation or topography 766 (Pimont et al 2014).…”

“…to alleviate the burden of cyclic conditions for investigation of heterogeneous canopies 811 (Pimont et al 2014).…”