Analytical modeling of solid material ignition under a radiant heat flux coming from a spreading fire front

This study aims at characterizing ignition of solid targets exposed to spreading fire fronts. In order to model radiant heat fluxes on targets in a realistic way, polynomial heat fluxes are chosen. Analytical solutions for the solid surface temperature evolution regarding different time-varying heat fluxes are discussed for high thermal inertia solids using a mathematical formalism, which allows for the methodology to be extended to the case of low thermal inertia. This formulation also allows calculation of ignition times for more realistic time-dependent fluxes than previous studies on the topic, providing a more general solution to the problem of solid material ignition. Polynomial coefficients are then obtained fitting heat flux coming from absorbing-emitting flames. A characterization of solid material ignition times regarding fire front rate of spread (ROS) is finally performed, showing the need to accurately model heat flux variations in ignition time calculations.

Aymeric Lamorlette. Analytical modeling of solid material ignition under a radiant heat flux coming from a spreading fire front. Journal of Thermal Science and Engineering Applications, 2014, 6 (4), pp.044501. ⟨10.1115/1.4028204⟩. ⟨hal-01059491⟩

Journal: Journal of Thermal Science and Engineering Applications

Date de publication: 01-01-2014

Auteurs:
  • Aymeric Lamorlette

Digital object identifier (doi): http://dx.doi.org/10.1115/1.4028204

x >