The effect of water mist nozzle settings on fire suppression of electric vehicles in garages

In recent years, along with the widespread use of electric vehicles (EV), EV fires have occurred frequently. However, few studies have investigated EV fires in confined spaces. To address this gap, this paper aims to explore the different aspects of fire evolution of EVs as well as examining the suppression effect of different water mist (WM) settings on these fires. Multiple simulations are carried out, using the Fire Dynamics Simulator (FDS) simulation tool, considering different numbers and working pressures of WM devices. The results highlighted that the number of WM devices had a more significant effect on the fire. Peak heat release was reduced by 17 % and peak arrival time was delayed by 26 % using 6 MPa with 3 nozzles compared to 0 nozzles. Additionally, it leads to accelerated mixing of the smoke layer with the air layer. Moreover, it was shown that the closer to the fire source in the vertical direction, the greater the degree of peak temperature decrease. In this regard, the maximum reduction in the measured temperature was around 70 %.