On the simulation of forced-ventilation fires

Fires occurring in a forced-ventilation compartment would be very different from those in a natural-ventilation compartment. The positions of the fresh air intake and the exhaust and the values of the ventilation rates are the important factors affecting the stability of the smoke layer and the burning process of the materials. If the air intake positions are located at upper levels and the extract positions at the lower levels, the hot gases cannot rise due to the strong air flow induced by the ventilation fans. The field modeling technique is applied to study the physical picture of the forced-ventilation fire. A self-developed computational package for studying building fires and the UNSAFE-N developed at the University of Notre Dame are the two simulation tools. A total of six simulations with the same ventilation flow rates but different air intake and exhaust positions are performed using the two field models. Results predicted are compared, and the calculated air temperatures are evaluated using the well-stirred model.