Study on Smoke Exhaust Performance in Tunnel Fires Based on Heat and Smoke Exhaust Efficiency Under the Lateral Centralized Mode

Autor: Linjie Li, Daiqiang Zhu, Shuping Jiang, Rongjun Xing, Pai Xu, Chuanyong Wen
Rok vydání: 2021
Předmět:
Zdroj: SSRN Electronic Journal.
ISSN: 1556-5068
Popis: When a tunnel fire occurs, using quantitative indicators to evaluate the performance of smoke extraction system and determining a reasonable exhaust volume to discharge high temperature and toxic smoke generated by the combustion is the key to ensuring the high efficiency of the tunnel smoke extraction system. Based on the transfer mechanism in heat and mass flow rate of smoke, theoretical models are established to calculate the heat and smoke exhaust efficiency of smoke inlets in each group and the smoke extraction system under the lateral centralized smoke exhaust mode by temperature and CO concentration. Fire Dynamics Simulator (FDS) is used to investigate the temperature and CO concentration changes in the tunnel and smoke duct under different exhaust volumes, and the heat and smoke exhaust efficiency are obtained. The larger the exhaust volume, the higher the total heat and smoke exhaust efficiency of the smoke extraction system. However, the phenomenon of plug-holing occurs in the lower left area of the smoke inlets. With the heat release rate of 20MW and no longitudinal ventilation, the smoke exhaust performance can be greatly improved when the single-sided exhaust volume is set to 180m3/s, that is, 1.85 times the minimum smoke exhaust volume.
Databáze: OpenAIRE