A Mixture Fraction Combustion Model for Large Scale Fire Modeling

A numerical fire model, Fire Dynamics Simulator (FDS), is being developed at NIST to study fire behavior and to evaluate the performance of fire protection systems in buildings. To date, about half of the applications of the model have been for design of smoke handling systems and sprinkler/detector activation studies. The other half consists of residential and industrial fire reconstructions. Improvements are being made to address the second set of applications, most importantly a mixture fraction combustion model and a finite volume radiation transport algorithm using either a gray gas or a wide band assumption. The methods will be discussed and a sample calculation presented.