Evaluate the fire suppression parameters using FDS
Abstract
It takes money, time, and energy to construct a fire and spray experimental rig. Due to advancement in technological development, it is easy to illustrate the experiment in computer simulation, especially by coding. The mist spray nozzle and sprinkler spray deluge nozzle are being coded and simulated using Fire Dynamic Simulator, (FDS) developed by National Institute of standards in technology (NIST). FDS is a Large Eddy Simulation (LES) model to represent turbulence. The liquid droplets are being injected into the spray nozzle using Lagrangian particles. The scenario is simulated under, presence and absence of fire and compare monodisperse with polydisperse spray under uniform spray condition. The simulations are simulated under 2 bar, 5 bar and 8 bar of pressure for deluge. 100 bar pressure for mist nozzle is simulated under presence and absence of fire. This study provides the study of suppression parameters such as number concentration, droplet diameter and velocity distribution. A grid sensitivity analysis is performed for improving the results. So, 10 cm and 5 cm has been chosen for this analysis and few scenarios were investigated to show the result comparison and accuracy. The modified geometry is modelled, and simulation was run to see improvements. The main difference was spotted that SMD gave 63 % in the simulation having default particles droplets per second & coarse grid. 100% diameter size distribution is achieved in the modified geometry. Upon analyzing the behavior, the user can get a sound idea on suppression parameters and use the fire suppression system according to the applications.