Installation of a water spray curtain system is a popular active fire safety measure. Placed between the fire and the protected object, it has the ability to attenuate thermal radiation emitted by the flames. The interaction of water sprays with the surrounding air flow and thermal radiation is hard to measure experimentally and to model. Any such modelling attempt needs to take into account the turbulent nature of the air flow, jet break-up and droplet generation, radiation absorption and scattering as well as heating and evaporation of water droplets. Despite the arising complexity, such modelling is necessary to predict performance and to conduct design optimization prior to the system deployment.
The lecture is based on the consultancy project in which an accident scenario of a fuel tank fire was studied. With the nearest buildings located only 45 m from the fire, the objective was to design a water curtain arrangement that reduces the level of thermal radiation to 3 kW per sqm. For that purpose, an algebraic parametric analysis of radiation attenuation through water sprays was conducted to find an adequate design solution. Furthermore, its results were then confirmed by CFD simulations.

Files

• Presentation slides (2021/01/07)