A Study of the Effects Sprinkler Water Droplet Sizes on Smoke Flow in a Tunnel Fire

• Main Authors: LIU, JIA-HONG, 劉家宏
• Other Authors: CHUAH, YEW-KHOY
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/j95d96

碩士 === 國立臺北科技大學 === 能源與冷凍空調工程系 === 107 === In this research, the different droplet size (≤1000μm) and different flow rates (80LPM and 160LPM) of the automatic sprinkler system were used to investigate the change of the smoke flow in the 20MW tunnel fire without wind field. Establish a whole tunnel 3D model; including fire source, tunnel structure, automatic fire sprinkler system, etc. The three dimensional computer models were built using Fire Dynamic Simulation. The fire is simulated in the center of the tunnel, while the situation is simulated without the influence of the wind and smoke exhaust system. According to the simulation results, the effects of water droplets with different sizes on the smoke flow are reviewed and considered as fire field strategies. This research applies FDS and adopts log-normal and Rosin-Rammler distribution in combination with the droplet size distribution to suppress the fire of the tunnel fire and the diffusion of smoke. And considers the parameters as following: (1). Volume flow rate (2). medium volumetric droplet diameter. As a result ,when the water flow rate is large, the fire suppression and cooling faster, which is more conducive to personnel escape. When the flow rate is fixed, the smaller particle size is harmful for fire suppression,and make low visibility. Because the tunnel is a high-risk space, it is not easy to rescue and escape. If the automatic sprinkler system can be quickly extinguished in the early stage, avoiding long-term combustion and causing structural collapse, it can ensure the safety of personnel and reduce economic losses.