الفهرس | Only 14 pages are availabe for public view |
Abstract Nowadays, firefighting considerations are mandatory for all projects all over the world. Water based automatic firefighting systems are widely used because of their effectiveness, reliability and economic considerations. Recently, water mist firefighting systems have proved to be an effective fire fighting performance. The present study is based on Computational Fluid Dynamics (CFD) investigation using FDS code (Fire Dynamic Simulation) in order to specify the effect of water mist droplet size, flow rate, and working pressure on gaseous fire suppression performance. Methane has been used as a gaseous burning fuel. Fire extinguishment time has been used as an indication for fire suppression effectiveness. Results show that the most dominant parameter for water mist gaseous fire suppression performance is droplet size. Large droplets water mist (400 urn up to 1000 urn) did not extinguish the gaseous fire regardless of the used flow rate or working pressure. Small droplets water mist (up to 250 urn) showed good performance. Increasing flow rate with small water mist droplets has improved extinguishment performance. Working pressure did not show any effect on gaseous fire suppression. So, low pressure small droplet water mist can be used effectively in gaseous firefighting p” ” " ~ " ” ”rposes. Finally, optimum values of studied parameters to obtain the optimum gaseous fire suppression performance using water mist have been identified (D = }oOllm, Q = 20 l/min, and P = 2.5 bar). |