Improved Radiation and Combustion Routines for a Large Eddy Simulation Fire Model

Improvements have been made to the combustion and radiation routines of a large eddy simulation fire model maintained by the National Institute of Standards and Technology. The combustion is based on a single transport equation for the mixture fraction with state relations that reflect the basic stoichiometry of the reaction. The radiation transport equa-tion is solved using the Finite Volume Method, usually with the gray gas assumption for large scale simulations for which soot is the dominant emitter and absorber. To make the model work for practical fire protection engineering problems, some approximations were made within the new algorithms. These approximations will be discussed and sample cal-culations presented. KEY WORDS: finite volume method, large eddy simulation, mixture fraction mode