Numerical Study on Heat Radiation Attenuation and Flow Characteristics by Water Mist Curtains

Abstract

A numerical study was conducted to investigate the attenuation effect of fire radiative heat and flow characteristics by water mist curtains. To shield a fire room with a diesel fire source with a maximum heat release rate of 1.8 MW, two mist curtain nozzles that operated at 1.0∼3.0 MPa were installed. The injection flow rate and mean diameter of droplets ranged from 9.1 to 15.8 lpm and from 87 to 58 μm, respectively. The radiative heat flux through the mist curtain was μ attenuated by 50%∼76% based on the given injection pressure range and appropriately followed the trends of previous experimental results. Comparing the flow characteristics with and without mist curtain activation, the effect of smoke shielding using the mist curtain was partially evident at the early stage of the fire; however, the shielding effect decreased, as the speed of the smoke flow increased during the peak period.