A study of the effect of a line of sprinklers on the fire induced air flow using the two-dimensional field modelling technique

The air drag and cooling effect of a line of sprinkler water spray on fire-induced hot air is studied using a two-dimensional field modelling technique. The sprinkler water spray is described by an imposed envelope with the shape obtained from the water droplet trajectories. The interaction between the fire-induced hot air and the sprinkler water droplet is described in the source terms of the enthalpy and momentum conservation equations, i.e., the Particle-Source-in-Cell method. The PISO scheme is used to solve the set of equations. In this way, a 'microscopic' description on the interaction between the sprinkler water sprays with the fire-induced hot air as well as the macroscopic parameters such as drag to buoyancy ratio, air entrainment rate and convective cooling amount is achieved.