A review of fire processes modeling of combustible materials under external heat flux

One-dimensional model is fundamental to two- or three-dimensional modeling of combustible materials, which can be classified into wood, non-charring polymer, charring polymer and intumescent polymer according to their characteristics. Four fire processes are involved in fire development, such as thermal process, physical process, chemical process and failure process. Consideration of all four fire processes for these combustible materials is significant to modeling accuracy and application fields. Therefore, the state of the art of one-dimensional modeling describing all four fire processes of woods, non-charring polymers, charring polymers and intumescent polymers under external heat flux was reviewed. A summary of typical considerations in previous one-dimensional models was provided, including heat conduction, pyrolysis, production of gas volatiles, volume change, water evaporation, internal gas pressure, properties of permeability and porosity, and mechanical behaviors. Empirical models and critical data of fire processes were also collected for modeling input. This paper can provide a guide to one-dimensional modeling and build basis for two- and three-dimensional modeling.