Smoke filling in closed compartments with elevated fire sources

An experimental study on smoke filling in closed compartments with elevated fire sources is presented. Experiments were conducted with elevated fires in a closed compartment with interior dimensions of 3.000 m (L) x 3.000 m (W) x 1.950 m (H). Various parameters, such as the light extinction coefficient, the oxygen concentration and the gas temperature, showed distinct stratification phenomena, and the interface of the stratification was the fuel surface level. The results indicated that the smoke layer descended to the fuel surface level but did not descend directly to the floor at the center of the compartment; rather, it continued the filling process by wall jets. A similar stratification was observed in a closed burning compartment with interior dimensions of 1.000 m (L) x 1.000 m (W) x 0.750 m (H) through tracking the smoke by a laser sheet. A visualization showed that the wall jets penetrated the interface, traveled along the wall, concentrated at the floor and then rose from the center of the floor. With continuous burning, the smoke filled the lower layer. (C) 2012 Elsevier Ltd. All rights reserved.