Fire Safety Science Digital Archive

Both numerical simulations and experimental measurements of small scale spontaneous ignition with different biomass fuels have been performed. In the experiments, temperature history was monitored at five different locations inside the fuel bed. The measured temperature history was used for validation of comprehensive three-dimensional computer simulations which were carried out using a parallel finite volume CFD code SMAFS (Smoke Movement and Flame Spread) developed by the first author. The computation was based on numerical solution of a set of governing equations including the continuity equation, extended Darcy momentum equations, energy conservation equations for both gas and solid phases, and mass conservation equations for different chemical species. Consideration was given to a series of essential physical and chemical processes, including convection and diffusion in porous media, evaporation, condensation and heat generation which is mainly due to chemical oxidation. With reliable material properties input data provided by separate measurements, it simulated the temporal state evolution inside the biomass fuel storage. Numerical results were compared with experimental measurements, showing excellent agreement.