重点排烟大断面隧道火灾烟气控制的CFD分析

CFD Study of Fire Smoke Control Effect in Large Section Shield Tunnel with Point Smoke Extraction Strategy

本文以在建的上海市虹梅南路越江隧道为对象,借助CFD(Computational fluiddynamics)技术,利用SMARTFIRE软件模拟了一系列工况。首先分析了大断面盾构隧道在20MW火灾规模工况下利用顶部排烟道进行重点排烟时,开启不同位置的三个排烟口对隧道内温度、能见度和一氧化碳浓度分布的影响及其随时间的变化规律;然后根据分析结果和世界道路协会提出的安全疏散指标,评价了虹梅南路隧道火灾时的疏散救援环境,给出了建议的排烟口开启方式。

This paper takes the South Hongmei Road Tunnel crossing the river under construction as an example. The selection of three-point extraction （3PE） opening strategy was analyzed for a 20 MW fire scenario. To investigate the fire characteristics in this large cross - section tunnel and develop appropriate smoke control strategies in fire accidents with 3PE system, a series of numerical 3D simulations were conducted by using SMARTFIRE. Based on the simulation results, smoke movement and temperature distributions within the tunnel under different smoke control strategies were presented. Further, according to the criterion of safe evacuation established by PIARC, evacuation environment within the tunnel were carefully evaluated at the position of evacuation path. Finally, an appropriate smoke control strategy for the South Hongmei Road Tunnel was also presented.