Computational fluid dynamics simulations of the impact of a water spray on a fire-induced smoke layer inside a hood

This article presents computational fluid dynamics results of the impact of a water spray on the fire smoke layer inside a hood. The models and the settings of parameters are discussed. Three experiments are performed by means of computational fluid dynamics simulations, and the comparisons show good agreement between measured data and predicted results. The simulation results provide insight into the temperature and flow fields for the configuration at hand, revealing an entrainment effect. The influence of the water spray characteristics on the downward smoke displacement due to drag and cooling is explained. Furthermore, an extensive sensitivity study of the simulation results to input parameters and mesh size is performed. The inner spray angle (related to vertical water flux) and droplet size are shown to be key parameters when simulating downward smoke displacement caused by a spray.