Experimental and numerical study on smoke evolution in polyethylene (PE) slabs enclosed compartment fire

Full-scale compartment fire experiment initiated by a corner gasoline pool fire was conducted to investigate the enhancement effect of polyethylene (PE) slabs attached on the internal walls on fire development and smoke evolution. An open door and an initially closed window served as the openings to provide natural ventilation condition. Corresponding numerical simulations, employing a CFD tool Fire Dynamics Simulation (FDS), were carried out as well to study the fire growth, smoke temperature, smoke layer height, and indoor visibility. Both PE and non-PE compartment fire circumstances were simulated to examine the intensifying mechanism of burning PE slabs. The results show that the attached PE slabs on the walls would greatly intensify the compartment fire and result in a much higher smoke temperature by about 325 °C, which could significantly facilitate the potential occurrence of flashover. The molten PE generated a considerable pool fire on the floor and resulted in a secondary peak in smoke temperature curve after the burnout of gasoline. However, this secondary peak is not found in the simulation results due to the neglect of melting and flowing process in numerical model. Some random ignition incidents in test, such as the splash of pool fire and collapse of furniture, contributed to the deviation between experimental and numerical results. Smoke layer height was empirically estimated to be 1.8 m and compared with numerical predictions. The empirical model predicted the smoke layer height well after the break of window at the steady state.